A Chemical Sabbatical

One of the Keys to a Good Presentations is...

2009-10-26T12:47:00.003-04:00

One thing (amon many) that bothers me during a presentation is a lack of consistency between graphs. Perhaps I’m just being a bit anal here, but it seems to me that talks should be designed so as to allow the listener to grasp what you are trying to say as quickly as possible. If the audience has to work too hard to understand a series of graphs, then the audience will stop paying attention.

Now I’m not talking about colors and fonts, although maintaining a consistent color scheme for data sets throughout a talk is a very good thing. (If you use red for sample #1 and blue for sample #2 on the first slide, keep it that way throughout the rest of the talk. I know that seems fairly obvious, but you’d be surprised how many people don’t pay attention to this. Far too many people who should know better just use whatever colors Powerpoint gives them.) No, I’m talking about inconsistencies in the way the data is plotted. For example, plotting some of your data using weight% and others using mole% (unless there is some special reason for doing so.)

This almost always happens because the presenter is too lazy to convert one (or more) of the plots. I’ve seen this at group meetings at work as well as at talks given at our local catalysis society meetings. In these cases, it’s obvious the presenter just tossed in a bunch of plots drawn by their students (or group members) and figured that was good enough.

I bring this up now since my current project involves lots of meetings with lots of presentations with lots of data and we’re running into the same problem. In this case, the problem stems from a lack of an agreed upon format. We work on fuel cells and it’s common to evaluate a cell by measuring its current output as a function of voltage. It’s called a polarization curve and is commonly plotted as amps versus voltage. That’s fine, but we have people from many different backgrounds - materials people, electrochemists, product engineers, graduates students from a local university, PhDs from one of the national labs – and everyone has their own preferences. Some like to plot watts (amps x volts) versus volts. Others plot current density (amps/cm2) versus volts while still others plot power density (watts/cm2) versus volts. If that wasn’t bad enough, sometimes the axes are flipped, so that voltage is now on the y-axis. And when they start mixing up these plots in their project updates – and they always do -- I spend half my time doing conversions in my head, just to figure out what the data really means.

So please keep your plots consistent. I may be in your audience one day and I’ll greatly appreciate it!

I would also like to apologize for the long delays between posts. I promise to start posting more often, like I used to do.

Bacteria - The New Chemists

2009-10-06T15:33:00.002-04:00

A new wave of chemists is on the horizon – and they are called microbiologists. Every day, it seems, I read an article about the use of bacteria to perform chemical synthesis, a job that rightly belongs to chemistry graduate students. Hydrogen, biodiesel fuels, drugs, and a few other organic compounds whose names I don’t remember are being produced by trained bacteria. I don’t know how many of these processes are commercially viable.... yet.... but I’m afraid it’s only a matter of time before graduate students will have nothing left to do other than caring for the bacteria in their labs.

In a similar and yet totally unrelated vein, here is another report detailing the use of bacteria to remove uranium from waste water.

According to the report:
“Bacteria, in this case, E. coli, break down a source of inositol phosphate (also called phytic acid), a phosphate storage material in seeds, to free the phosphate molecules. The phosphate then binds to the uranium forming a uranium phosphate precipitate on the bacterial cells that can be harvested to recover the uranium.”

While I’m sure we can probably always use another new technique for the removal of toxic heavy metals, I cannot help but wonder if having radioactive bacteria running around out in the open is such a good idea. I realize the radiation levels are pretty low, but this still seems like the basis for a movie on the Science Fiction channel.
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On another note, the 2009 Ig Noble awards have been announced and they are as funny as ever. The Chemistry prize goes to Javier Morales, Miguel Apátiga, and Victor M. Castaño for creating diamonds from tequila. I sure hope they have an MSDS for the starting material. The link is here. Thanks to Anne Marie Helmenstine's blog for the original link.

Modern Chemistry (Sets)

2009-09-18T15:39:00.000-04:00

My neighbor is planning to buy a chemistry set for her son (second grade) and she asked me for some suggestions. It was a chemistry set that I received back in second or third grade many years ago that sent me down the path to a career in chemistry, so I thought I’d spend a little time trying to find a good one. I’ve talked about this before, but they just don’t make chemistry sets the way they used to. Perhaps for safety reasons, perhaps for environmental reasons, perhaps for liability concerns – there just are not that many chemicals in chemistry sets any more. And that’s a real shame.

My chemistry set (Chemcraft) had plenty of chemicals in it, and there were plenty more you could order. These days, you are lucky to find ten chemicals in a set, sometimes as few as two or three. I did find a Thames and Kosmos set which contained 20 different chemicals, but many of them were boring and the set cost about $250! I finally suggested a less expensive version of the Thames and Kosmos set to my neighbor. Of all the sets I checked out, it appeared to be the best one. The deciding factor was the inclusion of potassium permanganate. Even my old chem. set didn’t have that one. How did permanganate slip through the safety police?

New World Order?

2009-09-02T08:25:00.002-04:00

Not really chemistry related, but….

There was one of these so-called “town hall” meetings in my area yesterday to discuss President Obama’s proposed health care plan. Turns out it was less than a mile from my house, which meant that all the streets in our neighborhood were filled with parked cars and frantic drivers attempting to find parking spaces. It took a while for me to drive my daughter to soccer practice.

Debates like this always bring out the crazies. I noticed one sign that read something like “This is the USA, not the USSR.” Ignoring the fact that the USSR no longer exists, comparing attempts to ensure that some kind of health care exists for the millions of people who cannot get it now to communism or socialism is beyond stupid. Might as well hold up a sign that says “I’m a moron.” Try to put a little thought into this debate people. There are plenty of valid reasons to like or dislike the plan. Let’s try and stick to the real issues, okay?

My wife tried going to the meeting, but she was turned away, along with hundreds of others, since the auditorium filled up quickly. On the way back home, she ran into one guy who explained why he was against the health plan -- because it was basically a government plot for population control. This plot was apparently a part of the world takeover by the New World Order. Implemented by the Illuminati, I suppose. Shades of Sarah Palin. I certainly hope he did not contribute to the gene pool.

Post-Doc Stories

2009-08-28T10:04:00.002-04:00

When a post-doc joins your group, you’re never sure exactly what you’re going to get. I’ve known both good ones and some not-so-good ones. The following is a story about one of the latter, whom I met during my graduate school days in Illinois.

He was not in my group, but belonged to a research group whose lab space I was sharing. The post-doc, whom I shall call Dr. Orange (only members of the group would understand the significance of that nickname), was from Sweden. His area of expertise was multinuclear NMR of transition metals and that was exactly what the professor desired. Everything seemed to be working out okay with Dr. Orange, until he was asked to prepare some sodium decavanadate (Na₆V₁₀O₂₈) for some simple V⁵¹ NMR measurements. It is a rather simple prep. You basically dissolve some vanadium(V) in water and manipulate the pH until beautiful orange crystals fall out of solution. I had made this stuff years before as an undergraduate and hadn’t had a problem. Unfortunately this prep was beyond Dr. Orange’s capabilities. Either the crystals failed to appear, or they appeared and then disappeared, or if they stayed around long enough to be filtered, the crystals would quickly decompose. (I think he had neglected to rinse his fritted glass filter after a sulfuric acid washing). I volunteered to do the prep myself, but the professor said no, that it was Dr. Orange’s responsibility.

Things started to turn ugly and he began blaming other members of his group for sabotaging his synthesis. For example, he was sure the now-you-see-them-now-you-don’t crystals had been stolen. He believed someone had actually gone through the trouble of filtering out the crystals when he was away, throwing them out (he was convinced he found a trail of orange drops leading to a wastebasket), and then returning everything back the way it was. Of course, he also thought his labmates were stealing his mail too. Rather paranoid if you ask me. Eventually the professor instructed Dr. Orange not to make any more accusations and to just finish the damn prep. We later discovered that the guy had gotten his PhD mostly by grabbing compounds off the shelf, or synthesized by other people, and running them through an NMR. He didn’t know much about chemicals themselves.

Of course, an NMR jock doesn’t have to be good at synthesis, as long as the NMR jock is good with NMRs. Unfortunately, Dr. Orange was not. He was given permission to use the departmental multinuclear NMR, but that ended just as badly as the decavanadate prep. He could never get the instrument to shim properly, he had trouble understanding the software, his spectra were often ugly, and he managed to somehow wipe out the entire operating system. Along with everyone else’s spectra. Twice. That’s a lot of angry grad students. After the second data wiping, he was only allowed to use the instrument during the day, and only under the supervision of one of the NMR techs. You can imagine how embarrassing this was to the professor who had hired him. Besides, all the best NMR data is taken after midnight anyway.

He disappeared at the end of the year, much like his crystals.

Back on the Air Again

2009-08-11T10:27:00.002-04:00

Here’s hoping that my long hiatus from blogging is about over. I returned from my Grand Canyon trip several weeks ago, but I just spent the last two weeks in Missouri with my family. After a long battle with Parkinson’s disease, my father passed away last week. He taught me a lot about life and I’ll miss him. Who knows how my life would have turned out had not my parents bought that chemistry set for my birthday back in grade school? Thanks for everything, Dad.

In a lighter bit of news, my wife came across Mythbusters the other night, a television show dedicated to proving or disproving various myths, commonly accepted beliefs, and stunts enacted on TV. I haven’t seen many episodes, but in this one the hosts were attempting to reenact a scene from an old MacGiver show, where MacGiver used the sodium+water reaction to blow up a masonry wall. Chemical experiments on TV? Okay, I’ll watch for a while. Unfortunately, anyone who has ever handled sodium would know the small piece of sodium which they were using (duplicating the MacGiver episode) was doomed to failure. I threw larger pieces than that into buckets of water back in high school. (Not that that means it’s a particularly smart thing to do, I might add). The safety precautions used by the show’s hosts were a little over the top, but then again, I don’t know how much experience these guys have with chemicals. When the sodium failed to make more than a loud noise, they eventually turned to using potassium (which is much more reactive) while also increasing the amount of metal to 500 grams. The explosion was more impressive visually, but as expected, the wall wasn’t even touched.

Of course the reason why sodium or potassium explodes is due to its reaction with water to form hydrogen and heat, which then proceeds to ignite with the oxygen in air. Despite the rather impressive sound produced by hydrogen explosions, the actual explosive force is rather low, unless large quantities are present (or if one tries to constrain it within a vessel that might shatter). Two summers ago, my kids attended a demonstration where hydrogen and air were bubbled through dishwashing soap to create a pile of foam which was scooped up by the demonstrator and ignited while still clinging to his hand. Impressive noise, but no damage to the fingers. Now I’m not knocking the potential dangers of hydrogen here. After all, I work on fuel cells, and we pipe pure hydrogen all over the lab, so our detection and alarm systems are quite elaborate, let me assure you. But hydrogen is usually only a problem if large amounts of it collect somewhere, like near the ceiling, which is why hydrogen detectors are always placed up there.

Hydrogen explosions are interesting in that most explosives, such as TNT, work because their ignition produces a huge volume of gas (much of it carbon dioxide) which rapidly expands. The combustion of hydrogen

H₂ + 0.5O₂ ----> H₂O

actually results in the loss of ½ molecule of gas, which might be expected to create an implosion instead, except that the large amount of energy released during the reaction heats the gas, causing it to expand rapidly per the ideal gas law. The thing that makes hydrogen particularly dangerous is its extremely fast flame propagation speed, which allows all the hydrogen to react nearly simultaneously, greatly increasing its explosive power.

I didn’t watch the whole show. Can anyone tell me if they were successful in making a working hang glider using the motor from a portable cement mixer?

A Real Sabbatical

2009-07-11T10:07:00.002-04:00

You may have noticed I haven't posted in a while. Basically, I've been busy with a lot of other things, including a recent vacation. My other projects require a fair amount of writing, and I can only do so much writing in a day before I explode. As a result, I have not been as diligent with posting on this blog as I should have been. Since the family and I are leaving tomorrow for the Grand Canyon, I'm pretty sure there will be no more posts next week either. Anyway, thanks for having checked in.

Note: It's apparently much easier to post when the weather is less than ideal.

Are You Ready for the Digital Transition?

2009-06-11T16:16:00.001-04:00

As most of you should know by now, the U.S. government mandated switch to digital television transmissions will occur tomorrow (Friday) at midnight. I’ll be stopping by the Comcast office on my way home tonight, picking up an extra converter box or two for our secondary TVs. We already have one for the main television. All the polls indicate there is still a lot of confusion out there about what needs to be done to prepare for the transition, and while I was initially amused by all this confusion, I have since learned just how easily it can be to get it wrong. I know, because I also got it wrong at first thanks, in part, to some badly worded announcements put out by Comcast.

Several months ago, Comcast was telling everyone (in this area at least) that if you were a subscriber with them, you would still receive all the same analog channels without being required to do anything.. We wouldn’t even notice the transition, they said. About a month and a half ago, the announcements changed. Only the over-the-air based analog channels would remain untouched. All the other analog channels, History Channel, Nickelodeon, Disney, Animal Planet, etc. (yes, we have kids) would disappear, reappearing in a digital format which would require a converter box to access. Although these channels are also analog based, at least by the time they arrive at our house, Comcast no longer refers to them as analog channels. That distinction is now reserved for over-the-air channels. Analog channels which do not originate from local broadcasting stations are now referred to as cable channels, a point which was missed by the people writing the earlier announcements.

At least the extra DTV boxes are free for a year.

Do We Really Need Another Element?

2009-06-11T14:57:00.000-04:00

Just great. They’ve officially decided to add element 112 to the periodic table. Like I really needed another name to memorize.

A Babelfish for Chemists

2009-06-04T13:33:00.001-04:00

As an undergraduate, I fulfilled my foreign language requirements by taking German. I found it moderately useful for translating a few chemistry papers needed for my research, but the process was admittedly painful. Scientific German is a lot different (read: harder) than conversational German. By the time I entered the job market, my translating ability had atrophied to the point where it was nothing more than a bullet on my resume. And unless you are very good at it, it’s more economical for the company to pay someone else to perform translations for you.

A report has been released in the Journal of Chemical Information and Modeling describing Lexichem, computer software designed to translate over 250,000 English chemical names into seven other languages and back again. Hmmmm…… I suspect I might have found this useful back in the day, not only for me, but for some professional translators as well. I recall reading through a compilation of abstracts on ceramic materials translated from Japanese articles several years ago. I kept running into the term “basic soil elements” which had me totally bewildered until I finally realized the translator was trying to say “alkaline earth elements”.

Original source: New Scientist

Arsenic (Again) and Drugs

2009-06-02T11:24:00.002-04:00

Following up on last week's post concerning the relationship between elevated levels of arsenic in drinking water and a diminished immune response to certain types of influenza (swine flu?), I ran across the following article describing the use of nanorust (actually tiny particles of iron oxide coated on sand) to provide a possible low cost means of removing arsenic from water. You can’t get much more inorganic than this.

In a previous post, I discussed my general reluctance for taking drugs, somewhat skeptical that it might be possible to develop a drug which didn’t cause some problem somewhere else in the body. Now, Derek Lowe has written a column describing how much we don’t know about drugs and their mechanisms inside the body. He even says:” I try not to take any medication unless I feel it's absolutely needed, and I'm often not very happy about taking it even then.” A man after my own heart! I just might finally consider throwing out all that aspirin I’ve been suspicious of for a while now.

Mediterranean Cyclones

2009-05-29T13:14:00.005-04:00

According to this article, scientists have developed a new method of forecasting cyclones in the Mediterranean Sea. This has nothing to do with chemistry, and I don't really care about the subject, but it does give me a chance to post a (rather poor) picture I took in Malta years ago.

This waterspout appeared near the town of Mellieha (where we were staying) during the last day of our trip. As far as I know, it's the closest I've ever been to a tornado. We felt pretty safe from our vantage point, but I'm not sure the crew of the freighter (not shown) felt the same way. We flew out of Malta early the next morning -- fortunately -- since the resulting torrential rains shut down much of the island along with the airport.

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Two new elemental podcast are now available at Chemistry World. This week's elements are zinc and radon.

Poisons of the Day - Part Ib

2009-05-28T08:17:00.000-04:00

When I started the “Poisons of the Day” series last year, I was hoping to update it a bit more regularly, but one post a year (plus an addendum) is pretty pathetic. I’ve had several partially written entries since last year, but general laziness has prevented me from finishing them up. Perhaps they’ll see the light of day in June. In the meantime, here is an addendum to the addendum to the original post concerning arsenic. Besides its well-established toxicity, it appears arsenic also makes us more susceptible to the flu.

It is already known that arsenic disrupts a large number of hormone pathways in the body, which may link it with a variety of hormonal related diseases. The link with cancer has already been established. Now, Joshua Hamilton and Courtney Kozul have demonstrated that, after five weeks of drinking water containing 100 ppb of arsenic, mice exposed to the H1N1 influenza virus are only able to generate a rather poor immune response (compared with non-arsenated mice). Several days are required to reach appropriate response levels and that delay can be costly. According to Hamilton, “One thing that did strike us, when we heard about the recent H1N1 outbreak, is Mexico has large areas of very high arsenic in their well water, including the areas where the flu first cropped up. We don't know that the Mexicans who got the flu were drinking high levels of arsenic, but it's an intriguing notion that this may have contributed,”

Perhaps. So it may be worth noting that arsenic concentrations of 100 ppb and higher can also be found in well water in many areas of the United States.

Fortunately, unlike heavy metals such as lead and mercury, arsenic does not accumulate in the body. “Arsenic goes right through us like table salt,” Hamilton says. “We believe for arsenic to have health consequences, it requires exposure day after day, year after year, such as through drinking water.”

If it weren't for BPA, I'd be drinking bottled water all the time.

The End of the Hydrogen Economy?

2009-05-22T10:51:00.003-04:00

Most of you probably missed it, but about two weeks ago, the Obama administration announced the cutting off of funds for research into the use of hydrogen fuel cells to power the next generation of cars and trucks. The reasoning? The technology was not expected to be viable within the next 10-20 years and the administration wanted to spend its (our) money on projects with a quicker payoff. The difficulties with using PEM (proton exchange membrane) fuel cells in cars and trucks are many. Problems with on-board hydrogen storage, the need to use high purity hydrogen (ppm levels of CO poison PEM fuel cells), low power densities, and the lack of a hydrogen infrastructure (e.g. filling stations) all have to be solved first. Basically, this is an admission that we’re still a long way off from the much touted hydrogen economy.

And it doesn't help that hydrogen may not be as "green" a fuel as first thought.

Note: Fortunately, this has no effect on my work on SOFCs (solid oxide fuel cells). SOFCs can utilize both H₂ and CO as fuels, both of which are produced by on-board reforming of gasoline or diesel fuel. SOFCs have their own set of difficulties, but they’re much closer to being solved.

The Science News Cycle

2009-05-21T13:08:00.003-04:00

PhD Comics has some interesting comics relating to science and the news. Here's one example:

Go check out the site.

Francium -- Probably Only Good For About One and a Third PhDs

2009-05-18T21:28:00.009-04:00

Two new elemental podcasts are available for download at chemistryworld. This week's elements of interest include Francium and Aluminum. The Fr podcast is especially interesting. Considering that Fr has a halflife on the order of 20 minutes, it's probably not a good idea to base your thesis on its chemistry. All the quick experiments have already been done. And it cannot be classified as a disappearing element since it's continually being generated by radioactive decay. It's estimated that the steady state amount of Fr on the earth at any one time is about a kilogram, which is another reason not to base your thesis on it.

^* Post title was edited based on Mitch's comment.

A Fear of Drugs

2009-05-14T08:13:00.004-04:00

My wife recently recovered from a lower respiratory infection which she picked up during our trip to Missouri. The source of the infection cannot be confirmed, but the woman who sat in the adjacent row on the plane with the severe cough who couldn’t bother to cover her mouth should probably avoid any dark alleys where my wife might be waiting. Anyway, one antibiotic, two steroids, and two weeks later, the wife is back to normal. As usual, I escaped unscathed, much to my wife’s annoyance.

It’s probably best that I don't get sick very often. My wife will dutifully take any and all pills prescribed by the doctor without the slightest hesitation, while I tend to avoid medicines and drugs like the plague, especially those to which I’ve never been exposed before. Maybe I’ve seen too many doctor/hospital/ER shows where the entire episode revolved around the life and death struggle of a patient who had either experienced a rare, life threatening reaction to some commonly prescribed medicine or else experienced a common, life threatening reaction to a incorrectly prescribed medicine. (Perhaps I just watch too much TV -- but that’s another issue). But the main reason I don’t relish the idea of taking drugs is that, as a chemist (admittedly with a limited biochemical background), I have some idea of just how insanely complex the chemistry is inside our bodies. It seems utterly impossible to me that the introduction of a new chemical into our systems wouldn’t cause havoc somewhere. Just think about how easy it is for small impurities to crap up a reaction in the lab. While the general success of the pharmaceutical industry does allay my fears to a certain extent, I am still cautious since most doctors will admit that taking a drug is always a compromise. The idea/hope is that the benefits outweigh the negative effects. And if we are lucky, the negative consequences go unnoticed by the patient and are eventually repairable by the body. As a result, my doctor, the pharmacist, and myself have come to an uneasy truce over the years.

Unfortunately, that truce has become a bit more shaky thanks to a talk I attended at a local chemistry group, brewingchemistry. The lecturer was Felix Schneider, a retired FDA chemist, and his talk was entitled “What Happened to the FDA?” Without giving a lot of details, the politicalization of the FDA in the last decade, along with attempts to outsource some of its responsibilities, has led to a less effective organization (to put it mildly). It sounds as though the FDA is attempting to fix itself, beginning with a move back toward directors wiwth more of a science background, but it will be an uphill climb.

Scary fact¹: Most of the large pharmaceutical companies do not make the active ingredients in the drugs we buy – they license them out to other manufacturing facilities. If I recall correctly, something like 75% of these plants are outside the United States, mostly foreign corporations. At the present rate of inspection, it has been estimated that it will require nearly 50 years before all these plants can be visited by the FDA. Just what I needed to hear, especially after hearing stories about what the FDA has found in sites they have visited.
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¹Some alcohol was consumed during the talk, so take these numbers with a grain of salt -- the inorganic kind.

Bioelectricity

2009-05-13T08:56:00.001-04:00

The “corn into ethanol as automotive fuel” supporters received another bit of bad news the other day. They were already smarting from criticisms that corn based ethanol would not only dramatically drive up the price of food but would also generate more greenhouse gas emissions than fossil fuels (once you take into account the entire life-cycle of corn growing/ethanol manufacturing). Now, Elliot Campbell (UCM), David Lobell (Stanford), and Chris Field (Stanford) have calculated you can get more energy per acre by simply burning the biomass (corn, switchgrass, or whatever you’re growing) to make electricity. Converting the biomass into ethanol just wastes a significant portion of its energy content. The authors also point out that an additional benefit of “bioelectricity” might be in the area of carbon sequestration. You can sequester carbon at a stationary power plant, but not for mobile sources like automobiles.

Of course, this only helps lower our dependence on oil if we’re all using electric cars.

Bad Science -- Toxic Salt

2009-05-11T08:21:00.002-04:00

The great promise of the Internet is that it allows everyone to share their opinions with the public. The curse of the Internet is that it allows everyone to share their opinions with the public. I occasionally run into web-based articles discussing some aspect of science written by people who obviously don’t know the first thing about the subject. Recently, I found myself greatly amused by the following article on table salt. Excessive salt intake is apparently bad for your health – not because it increases your blood pressure, but because refined salt contains dangerous chemicals the industry doesn’t want you to know about. Here’s a typical quote:

“One or two servings of refined salt won`t send you to the grave. But continued almost daily use will avail you to the perils of aluminum toxicity.”

Aluminum toxicity?

The author’s suggestion: Use only “organic” salt. An amusing oxymoron, to say the least. There are many more such pearls of wisdom within this article. For example, he seems to have a fear of NaF, which he describes as “a synthetic, poisonous fluoride.” Unless I’m misreading it’s LD₅₀, the amount of NaF you’d have to ingest for it to be toxic would probably cause your heart to explode due to a super elevated blood pressure brought on by all that sodium.

I’m sure the author means well, but this article could be the poster child for why chemistry should be a required course in high school.

Ruthenium Compound Splits Water

2009-05-06T10:31:00.010-04:00

If you work in the energy sector and your focus is on hydrogen, then chances are you spend a lot of time thinking about this reaction:

2H₂ + O₂ --> 2H₂O

Researchers in this field tend to fall into one of two groups. The first group wants to use hydrogen to generate energy, usually in the form of electricity via a fuel cell, and devotes its energies into driving the above reaction as far to the right as possible. The second group wants to use energy to generate hydrogen, usually by electrolysis, possibly using solar photons, and strives to drive the reaction as far to the left as possible. (A third group is concerned with hydrogen storage, using high surface area materials such as MOFs, but that’s a topic for another discussion). Although these the two groups would appear to be diametrically opposed, they have at least one thing in common. In both cases, the efficiencies of the processes are often dependent on the oxygen side of the reaction. During electrolysis, forming the O₂ is the hard part, which explains why most of the advancements in this area are related to the anode. The cobalt phosphate electrode coating announced by MIT last year would be one example. And in fuel cells, it’s the cathode that causes most of the headaches, since it’s more difficult to reduce O₂ then it is to oxidize H₂ (at the anode).

In an attempt to negate the need for electrodes, much work has been devoted to identifying transition metal complexes which might catalyze the photochemical splitting of water in solution. The results have been generally disappointing. In many cases, sacrificial reagents are required, usually to facilitate the formation of O₂, obviously limiting the usefulness of the process. In addition, since the H₂ and O₂ are usually co-generated at the same location, an additional step is required to isolate the H₂. Not good at all.

In a recent article in Science , David Milstein describes some ruthenium chemistry which may have some implications in the solar energy field. When water was added to a ruthenium compound they’ve been working with, a new hydrido-hydroxo complex was formed.

Upon heating, this new complex continues to react with water to produce a dihydroxo ruthenium complex along with free H₂. Irradiating this dihydroxo complex with a halogen lamp causes it to revert back to the original hydrido-hydroxo complex, along with the formation of O₂. Catalytic photochemical splitting of water without the use of sacrificial reagents. Not bad. Even better, since the H₂ and O₂ are produced during different steps, there are no separation issues to be dealt with. This process is a loooong way from being commercially viable, but I enjoy any chemistry where an organometallic compound reacts constructively with water without simply igniting or decomposing into an ugly pile of goo.

Osmium, Osmium, Everywhere

2009-04-23T13:54:00.003-04:00

I don’t use osmium much. In fact, I don’t think I’ve ever used an osmium compound, although I’m fairly certain I once picked up a bottle of OsO4. The sum total of my osmium knowledge consists of knowing OsO4 (osmium tetroxide) is quite toxic. However, it now appears that if I ever do have need of osmium, I can just go outside and grab some. A group of researchers has studied the distribution of osmium across the globe and found that a surprising amount of the element is now present in rain, in snow, and in our rivers.

Osmium naturally occurs along with copper and nickel and is a by-product of their manufacture. But all this osmium in our water system comes from another source – during the production of platinum – much of which is used for the manufacture of automotive exhaust catalysts. During the process of refining platinum, the ore is subjected to high temperatures to burn out sulfur impurities. But volatile OsO4 is also produced and it has been spreading. According to the researchers, the levels of osmium are still small enough that this may not be a health concern, at least so far….

Russia and South Africa produce over 90% of the world’s supply of platinum and neither country regulates these osmium emissions. The demand for platinum may have dropped temporarily due to the worldwide plunge in car and truck sales, but it will return eventually. In addition, the current generation of hydrogen fuel cells also depend upon platinum for their electrodes, which means the rate of osmium release will probably only increase in the future.
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Since I did mention platinum, I’ll point out that this week’s Chemistry In Its Element podcast covers platinum and its chemistry. Podcasts for many other elements are also available, including osmium, so feel free to see if your favorite element has been discussed yet.

Error Analysis

2009-04-20T15:36:00.004-04:00

I just ran across a discussion of errors, R values, and Gaussian distributions over at “The Curious Wavefunction” blog. Being able to estimate, understand, and interpret sources of experimental error is perhaps one of the most important skills you can develop. It can save your career, for one thing. I once attended an in-house presentation by a coworker who felt the need to explain what he was currently doing for the company. The coworker presented the following chart to summarize his data.

No, I’m not giving away valuable corporate data here. This chart is just something I whipped up using a random number generator, which, as it turns out, makes it a damn good representation of what we were shown at this presentation. Seriously. Members of the audience began looking at one another, wondering where this talk might be heading. Basically, the black dots represented the data under standard conditions (obviously noisy data), while the red dots represented the data after changing the variable of interest. After spending ten minutes describing the experimental procedure, he summed up his results by comparing the average of the standard data (black) with the average of the four red data points and then had the audacity to conclude that the variable did indeed have a small effect. Audacity is probably not the correct term here since that implies a certain knowledge on the part of the speaker as to the outrageousness of his statement. He was totally surprised by the general outrage displayed by certain members of the audience and the discussion became rather heated, which is rare at this company. Eventually, he countered with “Well, this is the data I got. What else can I say?”

A simple “My data is inconclusive” would have sufficed.

By the way, the guy no longer works at this company. To be honest, he left of his own accord and jumped to a new company, one which is actually in better financial shape than this one. He’s actually a nice guy and I wish him luck, especially since I may be calling on him for a job some day.

Miscellaneous Friday

2009-04-17T11:01:00.003-04:00

I was temporarily unemployed for a couple of months at the end of last year, but I never considered expressing my disappointment in the same manner as this unemployed chemist. I cannot imagine this sort of thing looking good on a resume, but I’ve been wrong before.
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Now I need to rant a bit.

Yesterday, I needed to download a software driver for a National Instruments GPIB interface card from the company’s website. It should have been a quick 50K download at most, requiring only about a minute of my “valuable” time. Annoyingly, the entire process took 45 minutes -- time that could have been better spent searching the Web for more antics by unemployed chemists. First, the website required me to register before downloading the file. Swine! I already paid for the hardware! Forcing me to register just to download the accompanying software is sooooooo last millennium. Check out your competitors’ web sites. And what’s with all the “required” questions? I can understand asking for my email address so I can be spammed, but do you really need the name of my firstborn?

After being granted access to the download page, I discovered the “driver” file was over 108MB. WTF??? Are they sending an operating system along with the driver? Please: make non-essential utilities a separate download. If I had been downloading this from home, it would have not been that big a deal, but my company’s firewall insisted on scanning the entire 108MB file for porn and viruses, and the scanner is not very fast.

Anyway, I feel better now.
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Our governor here in Michigan has been desperately trying to make the state less reliant on the automotive industry. For the past few years, she’s been pushing to make Michigan the biodiesel capital of the world. Last year, she was promoting solar cell technology, partly since we have several companies (Dow Corning, for example) which are in the photovoltaic arena. And yesterday, she announced a program designed to (hopefully) make Michigan the nation’s leader in the manufacturing of lithium ion batteries for electric and hybrid cars. $300M in tax credits, among other things, with an eye on grabbing a piece of the $2 billion earmarked by the federal government for advanced battery projects. Basically, she want s Michigan to be the "alternative energy" state -- not to be confused with the "alternative lifestyle" state. According to Governor Granholm, “We are going from rust to green.” Will this work? I don’t know, but all three areas have need of inorganic chemists and that’s definitely okay by me. All the chemistry based jobs listed around here are pharmaceutical based.

PAHs -- Not Found at Your Local Health Food Store

2009-04-15T09:34:00.003-04:00

Yesterday, my family and I returned from a five day visit with my parents in southwestern Missouri. This, of course, means I’ll be spending most of today actually recovering from the “vacation”. You have to love how that works. The travel part of the trip went smoothly, thankfully. No one got sick, the plane was on time, and there were no traffic problems; so we arrived in Springfield at the appointed time – only two hours before the tornadoes passed through. Ah, the joys of traveling!
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Several of the houses in our neighborhood (not mine) have asphalt driveways. They’re a popular option since they cost less to build than concrete driveways, but they require a yearly application of sealant for protection from the elements. Apparently, that sealant contains polycyclic aromatic hydrocarbons (PAHs). PAHs (sometimes referred to as polynuclear aromatics or PNAs) consist of three or more fused aromatic rings (anthracene is one example), and as you might guess, are not always the most healthy of chemicals. And according to a recent study, the PAHs from these sealants are making their way into the water system. Since many PAHs are carcinogenic, you can kind of understand the concern.

As an inorganic chemist, I never really had much contact with PAHs, but I did run into them a few years ago while working on reforming catalysts. These catalysts convert air and hydrocarbons (like gasoline or diesel fuel) into CO and H2, along with smaller amounts of methane. I began to notice the buildup of an orange/yellow/brown solid all throughout my vent lines, sometimes as far as 10 feet away from the reactor. This necessitated not only the periodic replacement of these lines, but also, to my great joy, a massive clean out of my mass spectrometer. An NMR revealed this solid to be a mixture of PAHs. A little research revealed that under hot (700C), reducing conditions, methane forms PAHs quite happily. A little more research revealed that PAHs have been found responsible for the higher than usual rates of testicular cancer among workers in the metal cutting industry. Cutting fluids contain PAHs, and wearing clothes which are constantly soaked with them was found to be a bad idea.

I elected to start wearing gloves. Anybody else have any interesting stories about carcinogenic materials with which they’ve worked?

On the lighter side, David Bradley has managed to convince a few people to reveal some of the more stupid things they have done in the lab. .
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I’ve decided to add a verification check in the comments section. I apologize for the inconvenience, but this blog seems to have been targeted by a bot which feels the need to leave garbage in the comments section and I’m getting tired of deleting it. Hopefully I’ll be able to drop it again in a couple of weeks.

New Chemistry Game!

2009-04-07T08:07:00.001-04:00

If you enjoyed playing the Spectral Game , here’s another one for you. The people over at Useful Chemistry have created the Chem Tiles Game. If you enjoy Newman projections, Lewis structures, and nomenclature, this is the game/quiz for you. Reminds me how much organic chemistry I’ve forgotten since my sophomore year.

Also, I congratulation the Michigan State basketball team on their amazing season. The Spartans went a lot farther in the tournament than most prognosticators had predicted. Unfortunately, they appeared to run out of gas last night when they were pretty much pounded by North Carolina. I’m not a particularly big fan of college basketball, but I can still appreciate the tenacity of underdogs.

Potassium Ferrate - The "Green" Oxidant

2009-04-03T14:25:00.004-04:00

K₂FeO₄ is pretty cool stuff. It’s relatively easy to make, has a nice purple color, and it’s a stronger oxidant than permanganate. Oh… and it reacts with water. You can dissolve it in water, but unless the solution is fairly alkaline, it will decompose rapidly, generating O₂ as a product. It is being investigated for use as a cathode material for so-called “super-iron” batteries (using zinc anodes) and for its use as an oxidant for organic reactions. But its biggest claim to fame is its role in the area of water treatment.

A description of the methods used in water treatment facilities is too large to describe here, but one common method is flocculation, a technique used by both the Egyptians and Romans. The addition of alum and/or iron salts to the water to be treated, along with some lime, results in the precipitation of Al(OH)₃, Fe(OH)₂, and Fe(OH)₃. As these precipitates sink, they drag undesirable particulate material along with them, resulting in cleaner water. Chlorine (or chloramines) is then added for disinfection purposes. Chlorine treatments are very successful at removing harmful bacteria, but there has always been a concern that its reaction with organic material still present in the water might form harmful compounds.

This concern has been confirmed by a recently completed 10-year study. Michael Plewa, a geneticist at the University of Illinois, has quantified the toxicity, genotoxicity, and carcinogenicity of these disinfectant by-products (DBPs) using a mammalian cell line specifically developed for this study. He found not only that these DBPs are harmful, but that the degree of toxicity can depend on other factors. For example, it was found that water which contained bromine and iodine (seawater or aquifers associated with ancient sea beds) generated even more toxic DBPs. And DBPs which contained nitrogen were more toxic, genotoxic, and carcinogenic than DBPs which contained no nitrogen.

Plewa is especially concerned with swimming pools and hot tubs, which he refers to as DBP reactors. Organic material from swimmers -- sweat, urine, sunscreen, cosmetics, as well as some disgusting stuff – sits in contact with the chlorinated water for long periods of time, generating DBP levels up to ten times higher than drinking water. This may explain the higher levels of bladder cancer found in people who spend a lot of time swimming in pools.

This is where potassium ferrate comes into play, at least for water treatment applications. If all the organic material could be removed prior to the application of chlorine, then DBPs couldn’t form. So instead of adding iron salts and lime to the water, one could just throw in some K₂FeO₄. Ferrate would chew up the organic material in the water and then decompose to form the Fe(OH)₃ precipitant which removes the particulate matter as usual. And unlike chlorine, you cannot really add too much ferrate – you’ll just end up with more harmless Fe(OH)3. For this reason, ferrate is often referred to as a "green" oxidant. And once the ferrrate has done its work, you can add chlorine without the fear of forming DBPs.

The use of ferrate for this purpose has been investigated for over thirty years. One of the big drawbacks has always been the cost of manufacturing K₂FeO₄, but last year Battelle announced a lower cost method for its production, so it may yet come to pass.

Chemists vs. Engineers

2009-04-01T08:44:00.004-04:00

One of the guys in our group at work is a co-op student from a local university. As part of his engineering degree, he spends every other semester working in our lab receiving a massive dose of industrial reality and forced indoctrination into the world of engineering. His current stint ends this week, so yesterday he presented a summation of this semester’s work to the group. It wasn’t supposed to be a big deal -- a quick, informal 15 minute talk -- but the head of our division (3 or 4 steps up the corporate ladder) decided she’d attend the presentation, and the intensity level ratcheted up a notch or two. Of course, the division head ended up asking all the questions while the rest of us just smiled and watched the student sweat.

The questions were all good, although many of them concerned engineering protocols and methodologies of which I am woefully (and thankfully ignorant). Unfortunately for the student, there wasn’t much data with which to defend himself, due to situations mostly beyond his control. There had been a two month delay in getting the equipment up and running, due to the time required to implement various safety features in our labs. For some unfathomable reason, the safety guys had been (and still are) very nervous about the prospect of piping pure hydrogen and carbon monoxide throughout the building. They take safety much more seriously in industry than they do in graduate school, where safety protocols often involve nothing more than wearing safety glasses and not eating food in the lab, both of which are largely ignored anyway.

Anyway, the presentation ended, 90 minutes later, with very little blood spilt, and with the conclusion that several of the test variables would need to be quantified (by me, unfortunately) before the student’s return in July. So less than two hours later I was attending a meeting to discuss the quantification of these variables – a meeting attended by myself and 3 engineers. I recall the various good-natured rivalries between chemists and chemical engineers back in school, but we all generally thought alike. But these guys are process engineers. Acronyms like DFSS, MCE, Green Y, Red X, and MFEA were flying fast and furious. Process engineers have a very different way of approaching these types of problems. As a chemist, I just want to understand which variables are of interest and how they affect the final results. Process engineers are more interested in maximizing the reproducibility and repeatability of those variables.

For example, let’s suppose I were tasked with improving a known chemical synthesis. I would try to understand the chemical steps involved, I would isolate the important variables, and I would systematically make changes to the procedure to increase the product yield. Process engineers would be more interested in making the prep more reproducible and operator independent (meaning that everyone who followed the written procedure would get exactly the same yield). As a chemist, I might try different methods of cleaning/drying/purifying the starting materials/solvents. Process engineers would rather write solvent specifications and protocols to ensure that the level of impurities were reproducible, although not necessarily lower. They would sacrifice yield for the holy grail of repeatability. In their world, attempts to maximize yields shouldn’t occur until later. Process engineers feel this mindset allows them to solve chemical related problems without having to actually understand the chemistry.

In yesterday’s meeting, these engineers actually wanted to devote almost half of our allotted time just verifying the repeatability of our test as a function of which of us was actually running the test. An analysis of the test variables in question would be squeezed in later. It’s going to be a long three months.
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Note: I'm not trying to rag on process engineers too much here. Their techniques are exactly what you need when you are trying to design and operate an industrial process. I would fail miserably were I to ever attempt such a thing. But these techniques don't work so well in the research arena. There is a reason why advanced development groups and product development groups are generally kept apart.

The CIMS -- No, Not the Sims

2009-03-26T22:53:00.003-04:00

So far, my new job appears to be working out pretty well. My official job title is "test engineer" although I'm neither an engineer nor well versed in the testing protocols so beloved by product engineers, but it's a job and it allows me to get my feet wet in the world of fuel cells. It's a good time to be getting in on this project, as the number of chemistry-related subprojects is beginning to grow quickly and most of the people in the group are engineers (non-chemical). Now don't misunderstand me, these engineers are very good process engineers and they've picked up a fair amount of chemical knowledge over the years, but some of these chemistry projects really need a chemist's touch to finish them in a timely fashion.

With these projects in mind, I've already been grabbing some of my old equipment from the company's storage facility. This equipment is still in storage after all these months partly because the shiny, new lab my old group was supposed to move into is still not completed and partly because there really aren't any chemists left in that group capable of using the equipment. Anyway, I never know exactly what I'm to find during these salvage excursions. Remember the warehouse scene at the end of the "Raiders of the Lost Ark"? That's what our storage site looks like. This week I struck paydirt and I brought back the CIMS unit.

CIMS stands for Chemical Ionization Mass Spectrometer and it's great for analyzing the products typically generated during gas phase heterogeneous catalysis. In general, mass spectrometers operate by ionizing molecules using a variety of methods, followed by their separation via magnetic fields. Most mass spectrometers are electron impact types, which means they ionize molecules by bombarding them with electrons. Unfortunately, a fair number of molecules, especially organic ones, do not take kindly to this technique and tend to fragment into smaller pieces before the spectrometer can detect them. The CIMS alleviates some of this problem by first ionizing an inert gas like Kr and then letting the Kr⁺ ions do all the ionization. This kindler, gentler approach allows many organic molecules to remain intact and thus detectable. As an additional bonus, the appropriate selection of source gas allows you to choose which molecules to ionize. For example, detecting CO in the presence of nitrogen is problematic as they both have the same mass. This usually leaves you with four choices: find another analytical method, ignore the CO, use helium for all your experiments, or choose a new project. But with the CIMS, Xe⁺ only ionizes the CO, allowing the N₂ to sail blissfully past the detectors.

It's not a high resolution instrument , so it only costs about $250K, but it is small (a cube about 2.5 feet per side), portable (it has wheels), and the software is sweet. The unit started right up without a hitch, but the xenon source gas cylinder is essentially empty. Xenon isn't cheap and the CIMS requires an isotopically pure sample ($$$) and so we're talking $3000 here. I haven't told the boss yet how much this free mass spectrometer is going to cost him.

I still miss working with lab glassware and synthetic chemistry, but I do have to admit this instrument does rock.
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It's old news, but I'd like to add my congratulations to M. Frederick Hawthorne for having been awarded the 2009 Priestley medal for his work on boron. I admit to not having paid much attention to boron chemistry since grad school, but Hawthorne is currently located at the University of Missouri (my alma mater) and anyone who can make a water soluble boron cluster is okay in my book.

Being Flexible as a Chemist

2009-03-24T08:31:00.009-04:00

My freshman year was almost over. Final exams would take place in about two weeks and I was already beginning to prepare myself mentally. Almost as an afterthought, the chemistry professor assigned us one last chapter to read on solid-state chemistry. It wasn’t a real assignment – the professor never mentioned the chapter again and as I correctly surmised, it wasn’t going to be covered on the final exam. It should have been a meaningless blip in my academic career, quickly forgotten, but I still remember that chapter after all these years, or at least the section which covered the concept of non-stoichiometric materials.

I remember absolutely hating it.

We had just spent the entire year having the “Law of Multiple Proportions” hammered into our brains. “Atoms combine in ratios of natural numbers,” they would say. “If you can’t grasp this basic concept, you’ll never get a job as a chemist. You’ll just have to settle for being a doctor or lawyer or telemarketer.” Frightening words indeed! But now, just weeks before the final, I was discovering that this law was more of a suggestion.

I think I even remember one of the provided examples. It was NiO_1.03. WTF? 1.03? What sort of sick joke was this? It looked like something a freshman engineer would write, one who hadn’t yet grasped the concept of rounding. This deviation from stoichiometry was within the experimental error associated with an elemental analysis. I cannot begin to imagine what my thesis advisor would have done had I submitted an article discussing the properties of the V₁₀O_27.97^6- ion. The beatings would have been severe. The whole idea seemed stupid to me.

Fast forward to the present and my mind is now quite a bit more receptive to this concept. The field of non-stoichiometric materials is huge, incredibly huge, due to their special properties (catalytic, electronic, and optical). As a transition metal chemist, I now understand that the many oxidation states available to most transition metals can lead to mixed oxides, many of which are non-stoichiometric. I’ve also come to the realization that over half of my projects over the years have involved non-stoichiometric oxides in some fashion. Examples would include ZrO₂/CeO₂ solid solutions, various doped metal oxide catalysts, zeolites, and, at the present time, fuel cell cathodes. (Strictly speaking, zeolites are not really considered non-stoichiometric materials since there are no mixed oxidation states available, but with formulae such as Na_xAl_xSiO_(2+2x), where x can be < 0.01, I’m still counting them.)

The defect sites in these non-stoichiometric oxides make them wonderful catalysts, especially for redox reactions. The vacancies left by the loss of oxygen atoms in the crystal structure can create materials with the ability for ion conduction (usually at higher temperatures). This leads to their use in gas sensors, batteries, and fuel cells. (La_1-xSr_x)_yMnO_3-z is a typical oxide used in fuel cell cathodes. Non-stoichiometric oxides are here to stay.

And I'm loving it.

The moral of the story: Don’t dismiss new concepts in chemistry until you’ve had a chance to work with them first.

Donut Powered Solar Cells

2009-03-22T22:39:00.005-04:00

I came across the following video this weekend. Apparently powdered donuts are an important constituent in the drive to harness the power of the sun. Yes, nano-chemists will do anything for attention. And yes, magnetic stirrers DO rule!

So the powdered sugar in donuts can contain up to 1% TiO₂? I guess organic chemistry always benefits from the addition of some inorganic chemicals.

This video is one of the entries in the ACS Nanotation Video contest. If you want to see more, click here.

EDIT: I now see that this video was already posted over at the Chemistry Blog earlier last week. Not sure how I missed it, but this demonstrates the importance of keeping up with the literature when writing about current events.

Disappearing Elements? - Part IV

2009-03-20T11:36:00.002-04:00

Yet another element has turned up on the “Where’s it going to come from in the future?” list. (See my earlier posts). Recently, Fetzthechemist discussed the use of Nd-Fe-B magnets slated to be used in upcoming wind-to-energy conversion devices. His point was that the world’s current capacity for producing neodymium was insufficient to meet these future needs. This doesn’t mean the project is necessarily doomed. As a general rule, the inevitable price spikes which occur whenever demand exceeds supply often leads to the discovery of new, albeit more expensive, sources and methods of extraction. But at what point does the difference between running out of an element and being unable to use it due to cost become moot? Developers of new technologies will need to start paying more attention to the future availability of their starting materials. Maybe those alchemists obsessed with the transmutation of metals were just preparing for the future.

I’ve also noticed that many of these disappearing elements seem to be associated with new energy technologies. My first post on this subject came after reading a stock analysis criticizing a company’s (First Solar) plan to significantly increase their solar cell production – a plan which would have required using 16% of the world’s current capacity of tellurium. Hopefully this is not a trend which will continue.
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On the brighter side, my son no longer needs training wheels for his bike. My enthusiasm, however, is somewhat dampened by the soreness which I’m now experiencing after having spent yesterday running along side his bike, trying to help him maintain balance, while accelerating down our street. (Our sub has no sidewalks) He was probably ready to learn this last summer, but we never got around to it. So it took him less than a day to learn, to my great relief.

The Alchemy of Zinc

2009-03-17T12:57:00.005-04:00

Back in the day, alchemists apparently spent all their time attempting to turn base metals into gold. I say apparently, since that is the common perception of alchemists. In reality, most alchemists were devoted to what was often referred to as the “Great Work.” According to alchemical theories, much of what is created by nature is imperfect, and by applying the art of alchemy, natural substances can be brought to a higher state of perfection. Since gold was the height of perfection for metals, it was thought that base metals could be transmuted into gold merely by removing these imperfections. The Philosophers Stone wasn’t just about making gold or the “Elixer of Life”, it was a process/device/concept for bringing about perfection.

Color was very important to the alchemists, perhaps since it was one of the few clues with which they had to go on during their experiments. Colors and color changes were rigorously recorded and eventually incorporated into many of the alchemical theories. Certain color sequences were expected during the path towards perfection. In the transmutation of base metals into gold, for example, a color sequence of black to white to yellow to purple was thought to be required. Later theories redefined the sequence as black to white to red. While this fascination with colors may have led them astray on occasion, it has also led to a vast array of wonderful, full color illustrations, intricately drawn and full of alchemical symbolism. Here is one such example.

An experiment often touted as reminiscent of alchemy and demonstrating the relative ease of generating color changes involves the apparent conversion of a copper penny into silver or gold. Simply dissolve some Zn powder in warm NaOH solution, toss in a penny, and watch the penny turn silver as a coating of Zn forms on its surface. Heating the penny turns it gold as the Zn and Cu alloy to form brass. (My kids were duly impressed when I performed this experiment for them, informing me that it was “awesome”, but considering they said the same thing when I turned phenolphthalein red, the “awesomeness” bar may be set pretty low.)

But why does this work? I’ve coated pennies with silver and mercury before, but zinc is more electropositive than copper. Based on electrochemical potentials, zinc shouldn’t plate out on copper -- copper should be plating out on zinc. Apparently I’m not the only person to wonder about this, as web pages devoted to this effect can be found throughout the Internet, for example, here and here.

First of all, Zn dissolves in NaOH to make zincate ion and hydrogen.

Zn + 2OH^- + 2H₂O ----> Zn(OH)₄^2- + H₂

Okay, that’s straightforward chemistry. But how does the copper reduce the Zn(OH)₄^2-? The answer is that it doesn’t. Surprisingly, copper is not the reductant . Copper is not oxidized and it does not go into solution. Copper’s role is to create a galvanic cell with the undissolved portion of the zinc powder. Zinc does not plate out on the penny until the copper is in direct contact with zinc metal. It turns out that zinc metal is the reductant, which sounds bizarre, at least to me. Once the zinc and copper metals are in contact and the galvanic cell is created, the zinc begins to oxidize…

Zn + 4OH^- ----> Zn(OH)₄^2- + 2e^-

And its electrons are now available to reduce the zincate ion near the surface of the penny...

Zn(OH)₄^2- + 2e^- ---> Zn + 4OH^-

So the overall reaction is:

Zn + Zn(OH)₄^2- ----> Zn(OH)₄^2- + Zn

Basically there is no net reaction! Which means the zinc is essentially just migrating from the surface of the zinc powder to the surface of the penny. At first glance, this would appear to violate the laws of thermodynamics, but obviously it doesn’t. I assume there is some sort of entropy effect here, perhaps related to the galvanic cell, but I don’t know the exact cause. In any case, this reaction appears just as mystical as alchemy itself!

If anyone happens to know any more about this process, I’d be happy to hear from you.

Should the American Automotive Industry Be Saved?

2009-03-11T11:49:00.003-04:00

Despite living in the Detroit area and working in the automotive sector, I’ve never mentioned the current plight of the American automakers, despite it being a major news story for the past several months. I have no idea if anyone outside of Michigan really cares one way or another about the subject, but what the heck – this is a blog and I have no chemistry items ready for today, so here’s my take….

As you might imagine, I’m generally for the idea of helping out the ailing auto industry. I admit to having a certain financial incentive in keeping the local economy from tanking even more than it already has. I also admit I probably wouldn’t care as much about the subject if I lived somewhere else. But I don’t, and since I’ve had a chance to see how the auto industry operates, up close and personal, I do perhaps have a little better idea about what’s happening than most people outside the state of Michigan, especially southern Republicans.

I’m certainly not an apologist for domestic automakers. I’ve laughed at, or cursed, many of their decisions over the years, and there have been plenty of instances in which I’ve thought the UAW should be blown up, but even I have to admit that things have indeed been changing (albeit slowly) over the last decade. Before I begin, I going to have to rant a little…

rant mode on
Forget all the crap you hear from politicians claiming that domestic automakers:
1. Haven’t changed for decades (hire a competent staff who has at least a clue about the auto industry)
2. haven’t worked on alternative energy vehicles (they could finance small countries with what they’ve spent in that area)
3. have been resisting tighter emissions and fuel economy requirements. (Okay, so that last one is definitely true, but name an industry that hasn’t. Energy related industries (a Republican favorite) like coal have resisted emissions and safety regulations for decades but haven’t been bashed for it the last 8 years. We’ll see if that changes now).
rant mode off

Look, had this crisis occurred ten years ago, I probably would have said, “Let them fail” too. They were behemoths, unable or unwilling to change, so perhaps a bankruptcy is what they needed. But after all the changes the automakers have gone through in the last 5-10 years to make themselves leaner, more responsive, and more cost effective, it would be a shame for them to fail now because of bad timing. Even the unions were beginning to understand that changes were coming, which I believe is one of the signs Armageddon is close at hand. It appeared that GM had turned things around. Their new cars were getting good reviews, they were selling well (before the credit crisis), the company’s cost structure was much better, the time required to design, develop, and build a new car was approaching that of their foreign competitors, and surveys indicated that they had pretty much matched the Japanese in terms of initial quality (it will be a few years before we know if how their 1-3 year quality grades out). Had the credit crisis not occurred when it did, we might well be reading glowing stories about how GM had turned it all around. But it did and so now certain decisions have to be made.

Do the automakers deserve to be saved? I don’t think they “deserve” it, but after all the changes they’ve made, they probably don’t “deserve” to fail either. Unfortunately, many of the U.S. Senators who bashed the automakers back in January were woefully ignorant (or pretending to be woefully ignorant -- surely their staffs can’t have been that misinformed) of these changes along with some basic facts about the automotive industry. Even if you ignore all the factual errors, the fact that the Senators which are pushing hardest for a domestic bankruptcy represent states which enjoy the presence of foreign auto plants and thus might benefit from such a bankruptcy lessens the validity of their arguments. Already, the argument that there is something inherently wrong with domestic automakers if they need to ask for government aid has been blown apart by the fact that even Toyota is doing the same thing. By the way, I should mention that those same foreign automakers have been quietly telling these Congressmen to tone down their rhetoric about the evils of government bailouts and the benefits of bankruptcy. A bankruptcy at GM would wipe out the already strained supplier base, which also supplies parts to the foreign automakers. Shutting down foreign owned auto plants in the south would not be particularly good for the people down there either.

Of course the real question is “What is in the best interests of the country?” Which will cost the country more? Bankruptcy or financial aid? And this is a question everyone must answer. If you don’t think a GM bankruptcy is going to affect you, you are kidding yourself. The domino effect of from a GM bankruptcy will take out a huge section of the economy, including areas that may not be apparent to people working in non-automotive areas. I’m not an economist, but it wouldn’t surprise me if such a collapse would prolong the current financial crisis by another 6 months, and that may be optomistic. Let’s make sure we get this right. Playing politics with this decision has the potential to damage the country even further.

OK, I’ll get down off the soapbox now.

Colorful Chemistry

2009-03-06T09:06:00.003-05:00

I suspect that one of the reasons I chose Inorganic chemistry as my major was due to the colorful chemistry of transition metal complexes. Organic compounds, at least the ones I saw during my first several years in college, were almost always white. And in those instances where some color was present, usually a rather boring pale yellow or brown, it was often due to the presence of impurities.

Unfortunately, the electronic transitions responsible for most of the transition metal colors are d-d transitions, which are generally forbidden under the rules of quantum mechanics, so it often requires fairly concentrated solutions to generate rich colors. There are the occasional exceptions – e.g. MnO₄^-, whose color is due to a quantum mechanically allowed electronic charge transition (the electron jumps from a metal orbital to an oxygen orbital) -- but generally, the extinction coefficients of most inorganic molecules are low.

So it’s rather ironic that a majority of the most deeply colored compounds are organic molecules. No forbidden electronic transitions here, just conjugated systems that can be tailored to absorb just about any wavelength of light in the visible and UV spectrum. This property has led to their use as dyes for over 4000 years. A list of the early dyes would include:

Alizarin – produced by the madder root
Carmine - obtained from the bodies of cochineal insects
Indigo – obtained from the indigo plant
Tyrian Purple – a brominated version of indigo, obtained from the Murex (a type of shellfish) in minute amounts, so quite expensive. Only affordable to the uber-wealthy, it eventually became seen as a symbol of royalty (thus the saying “born to the purple”). In Roman times, it was a capital offense to wear it if you were not a noble. Exposure of the dye to alkali turns it crimson, producing the color worn by Cardinals in the Catholic church.

Starting in the 1800s, many of these natural dyes were replaced with aniline based compounds produced from coal tar. Some of these are considered safe enough to eat, which is why Blue No. 2 (indigotine) is found both in your blue jeans and in your blue M&Ms. Not all of today’s dyes are synthetic. Carmine, which is still obtained from insects, is still used to impart a reddish color to some foods in the US, which is creating a bit of an uproar. Not surprisingly, the food industry is not enthused about telling consumers that some of their products are made from bugs.

The blue food coloring referred to as Brilliant Blue FCF (or Blue No. 1) has a noticeable side effect of which most parents are aware. Green poop. I remember the first time my six month old son presented me with such a gift. Unfortunately, he was suffering from some unknown intestinal disorder at the time which already had us a little worried. The only reason I didn’t immediately panic was that the bright Kelly green color was so artificial looking that it was hard to believe it was physiological in origin. Apparently purple goldfish crackers have Blue No. 1 in them.

Clustered Water Chemistry

2009-03-03T11:37:00.000-05:00

As an aqueous inorganic chemist by training (at least in grad school, although my horizons have expanded quite a bit due to my time in industry), I’ve spent a fair amount of time investigating and understanding the role of water in chemical reactions. When working with transition metals, this usually translates into accounting for aqueous coordination complexes, pH, and solvent effects. However, after perusing the Net these last few years, I now realize I have been woefully ignorant concerning the chemistry of water. I knew water tends to form loose clusters of molecules (due to hydrogen bonding), which accounts for some of its unusual properties, but I wasn’t aware of the immense importance of these clusters to its chemistry.

I am particularly upset that neither my professors nor my chemistry textbooks felt it necessary to cover this important aspect of aqueous chemistry. As a result, I’ve been forced to learn about clustered water on my own by visiting some rather arcane web sites – web sites that for some reason appear to contain a high percentage of viruses, bots, and other spyware. To make it even worse, most of the my information comes from sites which make a profit by selling devices or elixirs based on the unique properties of these water clusters, which means that the scientific basis for these properties are often poorly explained. (These people really need some spell checkers!)

Here is what I’ve been able to deduce from my research:

1. There is a form of clustered water which has very unusual properties. Scientists are generally unaware of this form of water since it disappeared from the earth in the distant past. However, it can still be found naturally in very old glaciers and newborn babies. Yes, we are born with our own supply of the stuff, but we lose it as we age (being replaced by ordinary water) and this leads to disease and the overall decay of our bodies. I can only assume the major pharmaceutical companies are working feverously on this in secret as I type.

2. Clustered water has a different surface tension than normal water. Unfortunately, there is disagreement as to whether it’s higher or lower. Regardless, this difference in surface tension allows it to permeate cell membranes more readily which keeps our cells more hydrated… and healthy… and happy.

3. Clustered water retains a memory of the impurities which were trapped inside these clusters in the past. Although this sounds suspiciously like the failed theory of "water memory" proposed by Jacques Benveniste, this time it’s for real! Unfortunately, this has led to some confusion amongst the makers of clustered water products. Some marketers want you to ingest water clusters which have been exposed to very dilute solutions of vitamins to help replenish the body. Others feel it is the ingestion of clustered water which has been previously exposed to toxins which causes all our problems. These people want to sell you devices for purging your body of bad clusters. The scientific world is still debating this one.

4. Clustered water can impart its properties to ordinary water. So it’s cheaper to buy a concentrated bottle of clustered water and dilute it with ordinary tap water.

5. Changing the bond angle within the water molecules results in a burst of light which affects your DNA. Apparently, this turns out to be a good thing. I’m not quite sure I understand everything that was explained on the web site, but I believe changing the bond angle can be done using sound vibrations. Gregorian chants are particularly good. In any case, we should all be aware of the possible effects of MP3 players on our lab experiments.

6. Clustered water is not to be confused with the fictional compound Ice-Nine, mentioned in Kurt Vonnegut’s book, Cat’s Cradle. Clustered water is real.

If you wish to read more about this fascinating area, visit the Water Cluster Quackery page.

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Woohoo! We now have vending machines at work! Our work site now is relevant!

Adatoms?

2009-02-24T08:21:00.003-05:00

A few weeks ago, I attended a talk given by Professor John Yates at the local Michigan Catalysis Society meeting. John Yates (University of Virginia) is a well respected figure in the area of surface chemistry and catalysis. I hadn’t heard him speak before, but I was looking forward to it since, according to a friend of mine, John could make a talk on life insurance interesting. I was not disappointed. On a side note, he looks pretty damn good for someone in his 70's. His talk centered on self-assembled thiol complexes on gold surfaces. Interested parties might read the following paper: P. Maksymovych, D. C. Sorescu and J. T. Yates, Jr., “Gold-Adatom-Mediated Bonding in Self-Assembled Short-Chain Alkanethiolate Species on the Au(111) Surface,” Phys. Rev. Lett. 97, 146103 (2006).

John spent a fair amount of time discussing gold “adatoms.” What are adatoms, you ask?

No. Not this guy.

An adatom is an “adsorbed atom” and is usually described as a single atom sitting on a crystal surface. Adatoms have been around for years, but I’d never heard of the term before, despite the fact that I’ve apparently been making them for years. Simply exposing Pt to a hydrogen molecule, for example, will lead to the formation of hydrogen adatoms on the Pt surface. Of course, many of us who work on catalyst development would not think of these as adatoms, since in our line of work, exposure to even tiny amounts of hydrogen would essentially cover the entire surface of the platinum with a layer of hydrogen atoms, which doesn’t really fit the adatom definition.

What I found interesting was that Au, Ag, and Cu have the ability to generate their own adatoms. Due to structural strains in the crystal packing of these metals, individual atoms tend to pop out of the bulk to form single atoms on the surface. Assuming I understand this correctly, these adatoms tend to appear in a regularly repeating two dimensional pattern across the surface. Molecules (such as thiols) can bind to these adatoms, creating a surface layer with unique chemical properties. (Note: It’s possible that exposure to these binding molecules actually helps cause the adatoms to appear on the surface in the first place, but I don’t know. Perhaps someone else can answer that question.) Interesting chemistry indeed.
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I see that I passed the one year anniversary of this blog back in January. It’s unfortunate that it occurred during a dry spell, but I’m happy the blog is still going. The percentage of blogs that last more than a year is fairly low, so I can’t complain.

First Week Back At Work

2009-02-16T13:30:00.002-05:00

Well, I'm a week into my new job and things are beginning to settle down.

A little.

Even though I'm working for the same company as before, I'm working at a totally different location on a totally different project under a whole new set of rules and regulations. Although I know I'm working on fuel cells, my specific duties have yet to be fully determined. One of my initial assignments is to get the various testing facilities up and running, but I can see that I'm going to be needed in many different areas. The manager of the project has apparently decided to let me decide where I should be focusing my efforts. Hopefully I don't disappoint. I'm certainly not going to be bored. Here are the pros and cons so far:

Pros
--I'm getting paid. Yeah!!!!!!!! (Come on, what did you expect?)
--The project looks like fun. There's a lot of interesting chemistry happening here.
--Sorry, that's all I've got.

Cons
--Long commute. It's a 55 minute commute each way now, but it could be worse, so I won't complain too much. Some of my coworkers have even longer commutes. Such is your fate when you work for a company in the midst of a significant downsizing.
--No phone number, computer logon ID, email address, or computer! I have to request these things and the response time is yet to be determined. I'm currently borrowing a computer for making notes and browsing the net, but someone else has to log me in on their account every day for this to work. The lack of ID means I can't be the first person to arrive in the morning or the last person out at night, else I'll be setting off alarms.
--There are no vending machines here! Not even for soda! Not enough people here to support them I suppose, but I was under the impression that OSHA regulations required their presence at all work facilities. ;)

I previously wrote that I needed more structure in my life in order to keep up with this blog. Beware of what you wish for! I definitely have structure in my life now, but at the expense of free time. We'll see how this translates into blog entries.

Photo Chemistry

2009-02-02T23:39:00.000-05:00

A few weeks ago, my wife began taking a photography class at a local college. Although her real interest is in the area of digital photography, course prerequisites require her to take an initial course using real film. One of the things the course is designed to teach is how to develop your own film, so she's getting some hands-on experience in some basic chemistry. She may never use any of this knowledge, but she does seem to be enjoying the class.

In any case, she's reached the section of the textbook which covers the chemical aspects of film development and she's already asked me for help on her homework questions. Unfortunately, the questions turned out to be a little bit more difficult than I expected. This was due in part to the fact that the chemistry questions were written by someone who obviously was not a chemist, which always adds to the degree of difficulty. This meant I spent a lot of time trying to determine exactly what the instructor "thought" he was asking and what type of answer he was hoping for. (Now I don't mean to suggest that the non-chemist is always to blame in situations like this. Sometimes it's the chemist who is the problem. I recall trying to answer a Trivial Pursuit question many years ago which read "Glass is made out of what?" The answer, of course, was "sand", but all I could think of were answers like "silica" or other more esoteric chemical terms, despite being given the hint not to think like a chemist.)

The other difficulty arose when I came to the realization that I knew less about the chemistry of film than I thought. I knew that silver halide salts (the main ingredient in film) are light sensitive, decomposing to black silver metal upon exposure to light. After all, that's why silver salts are always shipped in dark brown bottles. And I had known about the role of sodium thiosulfate in the fixer (dissolving and removing unreacted silver halide) since I was a freshman. But what did the developer do? And what is a stop bath?

Apparently, the initial exposure to light only reduces a small fraction of the silver halide in the film -- not nearly enough to make a negative. The developer operates by magnifying the amount of silver reduced to the metallic state. The developer contains organic compounds (such as hydroquinone or p-aminophenol) which are good at reducing silver halides in the film, but only when catalyzed by the presence of small metallic silver clusters (such as Ag₄^o) which were formed during the initial exposure to light. The grain size of the silver halide particles are an important determiner of the amount of silver reduced by the developer, and this fact is used to produce films with different speeds.

And the stop bath? It's basically a solution of acid which lowers the pH of the developer and essentially halts the further reduction of silver halide.

At least my wife is experiencing the joys of using graduated cylinders in her lab. Maybe I'll make a chemist out of her yet!

Why Free Time and Blogs Do Not Mix

2009-01-28T18:30:00.010-05:00

The biggest reason why I haven't been updating my blog lately (other than laziness) is apparently due to having too much free time. Strange as it may seem, I am finding I require a certain minimum level of structure in my life in order to post anything on this blog. Back when I lived in the land of employment, there was structure. Searching the net for interesting science articles at work (during lunch, of course) was a regular routine and this process generated most of the ideas about which I posted. When I'm home all day, I never get around to performing this ritual until late at night, and then I feel obliged to work on my resume, or rearranging my office, or any of the other tasks I managed to avoid during the day.

Well it looks like that practice is about to stop.

Unless something unforeseen occurs, I should be entering the land of the employed in about a week. Now before you all start cheering too loudly, I should point out this job is not a permanent position. It's a contract position, with a length of one year, and the salary is significantly less than my prior job. And it's not going to involve a lot of interesting research on my part either, at least not for a while. I'll be developing computer automated test reactors for the evaluation of fuel cells. Not what I'd call an ideal position, but it will help keep us financially secure until I do locate a more favorable, permanent position. To say the national job market for inorganic chemists has fallen off a cliff is an understatement. The trick will be to ride it out for a couple of years until the job market opens up.

The funny thing is -- I am going to be working for the same company I was laid off from two months ago. I was only able to pull this off because:
1. it's a contract position, which means they can cut me loose at any time, and considering the precarious state of the company, that time could be measured in months or weeks.
2. it's at a different facility, which unfortunately means a 50-60 minute commute each way.
3. it involves a product area in which they are very excited. And the fact that this project is partially funded by the government actually allowed them to hire someone.

Anyway, I hope to be spending lunch breaks posting in a more regular fashion soon.

More Bad News

2009-01-15T22:19:00.004-05:00

I just learned that there are going to be more layoffs at my former company. Unfortunately, one of the guys I worked closely with was tapped this time. All the competent researchers from that particular division are now basically gone. This does not bode well for the future of that division or the company overall.

Hydrate Chemistry

2009-01-14T21:18:00.013-05:00

As I've previously indicated on this blog, I am primarily an AQUEOUS inorganic chemist. As such, I've prepared a wide variety of aquated metal complexes over the years, but I've never paid much attention to solid hydrate chemistry. And that's a shame, since there is a lot of good chemistry in that area, some of which I'm dealing with right now.

A few months ago, we decorated our ceilings with crown molding. Unfortunately, the original builders of our house placed the water pipes too close to the ceiling, which meant that two months after the crown molding was added, the FOUR nails which had punctured the pipes rusted and caused the pipes to leak. The resulting repair left a hole in the ceiling which was my job to fix. The material of choice for this type of repair is drywall (sometimes called sheetrock). Drywall is prepared by mixing CaSO4 · 1/2H2O with water to form CaSO4 · 2H2O, a hydrate with enough strength to be used to construct walls. Considering the fact that the added water forms no bonds other than hydrogen bonds, it's a little surprising that the resulting hydrate is so stable.

Of course, the strength of CaSO4 · 2H2O is nothing compared to that of another well-known hydrate. Cement begins as a mixture of CaO and SiO2 in various proportions, which is then reacted with water to form a calcium silicate hydrate.

2 Ca3SiO5 + 7 H2O —> 3 CaO · 2 SiO2 · 4 H2O +3 Ca(OH)2

Actually there is an entire series of hydration reactions which occur during the hardening of cement, with reaction times ranging from hours to weeks. Again, the strength generated by the formation of a hydrate is simply amazing.

Another hydrate with interesting chemistry is methane hydrate. Containing 5-6 molecules of water for every molecule of methane, this material can be found in huge quantities along the ocean floor. Wiki link here. It has been described as both a huge, untapped energy reserve and a major source of greenhouse gas. The latter description has become more significant as the temperature of the oceans continues to rise, since methane hydrate is only stable at low temperatures. It's also been used to explain the disappearance of ships in the Bermuda Triangle. What more could you ask from a simple compound?

Anyway, the ceiling is fixed.

The Power of TV

2009-01-12T12:21:00.002-05:00

One of the advantages of a “career transition” is that it allows one to watch alarmingly high amounts of TV during the day (while doing Internet job searches, of course). And while I appreciate having been granted this boon, it’s probably not worth the I.Q. points I’ve had to give up for the privilege. Lately, my wife has developed the habit of watching HGTV (Home & Garden TV) whenever she finds nothing else worth watching. Unfortunately, this means we have HGTV on at least 6 hours a day.

(Yes, we are one of those families where the TV is on almost continously all day, even if no one is watching. Frankly, the silence generated by turning it off scares the hell out of me.)

Long time readers know that I’m into gardening (garden link here), so I used to enjoy HGTV, but lately they’ve been ignoring the garden aspect and concentrating solely on houses. Remodeling houses, appraising houses, selling houses, buying houses, swapping houses -- it doesn’t take a genius to realize that all these shows are going to look the same. I realize the housing crisis has led to a renewed interest in how to sell your house -- or how to remodel it if you can’t -- but you can only remodel a kitchen so many ways. You can only gasp at poorly decorated homes so many times. You can only laugh at a homeowner’s first experience with a hammer so many times. And that, basically, is a summation of about 80% of the shows. The other 20% involves laughing at the tacky artistic remodeling touches added by the show’s designers, which would never see the light of day if the owners were actually paying for them.

However, what really drive me crazy are the “What is my house worth?” shows. First of all, either these shows were taped 2 years ago or else the realtors who supposedly “appraise” the houses are incompetent fools, or liars, or incompetently foolish liars. In almost every case, the “supposed” appreciations of these houses are outrageously high. It’s not uncommon for an owner to have purchased a house 3 years ago for $300k, added $100k in upgrades, and then being told it’s now worth $800k. Even in the housing boom, that would have been remarkable. But these days? Who are they kidding? Obviously there are certain locations within in the United States where housing prices are climbing (at least, so far), but unless these shows are only filming in those specific areas, there is no way these prices are real.

What really appalls me though, is the reason for these appraisals. When the owners are asked the reason behind the appraisal, the most common answer is that they are considering a major renovation and want to know if the house has appreciated enough to pay for that upgrade. Morons! Either you have the money or you don’t! Using a “supposed” increase in the price of your house to pay for a renovation is like pulling money out of your savings account and thinking you just made a profit. Don’t these people realize that it was this kind of “logic” that got us into the housing crisis in the first place. Basing financial decisions on artificially inflated values of real estate is stupid.

Seriously, some of these people need to be kept out of the gene pool!

I feel better now.

Tomorrow -- Real Science: Nostradamus on the History Channel!

Home Grown Titanium

2009-01-06T23:01:00.009-05:00

Although my current lack of posting might not indicate it, I've actually come across quite a few interesting articles lately. Unfortunately, they all involve nanochemistry, and since I've already talked too much about nanochemistry recently, I'm imposing a moratorium on that subject for awhile. Fortunately, I do have something else to talk about.

The Goldschmidt reaction.

Not familiar with the Goldschmidt reaction? Perhaps you have heard of it referred to as "the thermite reaction."

Surely everyone who has ever taken a freshman chemistry course has read or heard about the thermite reaction. Most of you have probably seen it in action. The pyrotechnics are impressive and most freshman chemistry lecturers simply cannot resist demonstrating it in front of a class. In its most common incarnation, aluminum and Fe2O3 (or Fe3O4) powders are mixed and ignited. The aluminum is converted to Al2O3 while the iron oxide is reduced to the metallic state. Significant quantities of heat are released, and if the experiment is set up correctly, molten iron will drip out of the bottom of the reaction vessel. Although iron oxide is the material most associated with the thermite reaction, copper and manganese oxides can also be used.

In a continuation of "the type of experiments I'd like to try at home when my wife is away" category, I recently came across a method for generating titanium metal in your garage using TiO2 and the thermite reaction. A full description of the technique as well as a video of the pyrotechnics are included. Metallic titanium was actually recovered, which is amazing since titanium tends to oxidize in air at temperatures near its melting point. In order to generate the temperatures necessary to melt the titanium, CaSO4 was added to generate additional heat. CaSO4 reacts with aluminum in its own version of the thermite reaction to form CaS. A more detailed description of the process involved can be found here.

This would have been an awesome experiment for alchemists to have performed back in the day. Simple, yet impressive. Perhaps the substitution of iron oxide with some form of gold oxide (or other suitable gold compound) might have resulted in the appearance of molten gold, always a good way to impress the wealthy patrons upon whom the alchemists depended. Unfortunately, although aluminum salts were known to the alchemists as far back as ancient Greece, aluminum metal was not produced until the 1800's. And it's the chemical energy stored in the metal which drives the whole reaction.

More Nanoparticle Bondage

2008-12-31T00:40:00.006-05:00

In a previous entry, I mentioned a technique whereby gold nanoparticles could be attached to the exterior of fungal cells to form unusual hybrid materials. Once the gold scaffolding was complete, the fungi could be removed (digested), leaving behind 3 dimensional gold structures. This started me thinking that there might be a rich field of exploration here, finding simple ways of attaching metal nanoparticles like gold to new substrates in the hopes of creating new 3-dimensional structures with unusual properties. Even better, many of these techniques would be based on aqueous chemistry, which make them especially appealing (to me at least).

Of course, within a week or two of that article, two more articles appeared which demonstrated that other research groups are already way ahead of me in this area.

In the first paper, J. P. Hinestroza and coauthors at Cornell University (Ithaca, NY) and the University of California, Davis, described a method of applying silver nanoparticles to porous nylon fibers, resulting in fibers with strong antibacterial properties. By using AQUEOUS chemistry techniques (pH control, isoelectric points, citrate stabilization, etc.), they found they could control the resulting properties of the final material. When you consider the fact that the original gold and silver nanoparticles can be easily produced by reducing aqueous solutions of the metal salts, you begin to realize just how much fun this type of project could be for an aqueous inorganic chemist like myself.

In the second paper, Y. Yin and co-workers at the University of California, Riverside, described the synthesis of gold nanoparticle catalysts supported on silica-encapsulated Fe3O4 spheres and protected by a porous silica shell. The purpose of the silica shell was to fix the gold nanoparticles in place for catalysis. Apparently the resulting material were found to be a good catalyst for the liquid-phase reduction of 4-nitrophenol with NaBH4. Interestingly, the purpose of placing the catalyst onto Fe3O4 cores was to give the researchers a convenient way of separating the catalyst from the reaction mixture. Nice.

I'm predicting a whole slew of papers are going to start appearing which involve placing gold and silver nanoparticles on every material imaginable.

Of course, maybe that's already happened and I just haven't noticed yet.

Ah yes..., it feels good to be blogging again.

Merry Christmas

2008-12-25T20:06:00.002-05:00

I naively thought all the extra time I would have available to me during my career transition would translate into my having more time to devote to this blog. I actually do have extra time, despite all the inevitable timesinks (job search, buying presents, rearranging my office at home, etc.). However, I've also discovered that it's a lot harder for me to update this blog if I am not following a regular schedule throughout the day. So I ask you to bear with me as I begin to develop a regular routine.

I hope everyone has a very merry Christmas today.

Update

2008-12-09T16:24:00.001-05:00

Well that didn't take long. I am officially a patient now. Damn viruses.

Another Use for Copper

2008-12-09T01:21:00.000-05:00

I've just returned from a 5 day visit with my parents in Missouri (which partly explains my recent lack of postings). It was great to visit, but it's always good to come back home again. Unfortunately, "home" is 20 degrees colder, my wife's computer had stopped working, and everyone in the house has some sort of vicious stomach virus. I briefly considered going to a motel, but my wife would have killed me.

Really.

So I spent Monday passing out medicines, cleaning up various messes, mostly eating by myself, and fixing the computer. The computer's working now, which is more than I can say for the rest of the family. I've already resigned myself to the inevitability of becoming a patient myself within the next couple of days. Perhaps I should invest in some copper bedsheets.

Why copper, you ask?

I have previously discussed the anti-bacterial properties of silver and gold. The list of purchasable items containing silver grows daily, and includes bandages, socks, towels, bedsheets, ointments, plastic food containers, soaps, and washing machines. Gold is not at that level of marketability yet, with gold-laced soap being the main use of its anti-bacterial properties. So it only makes sense that copper, the third element in the 1B group, also exhibits some of these same properties. In fact, in Chili, the biggest suppler of copper, copper fibers are being added to socks, towels, pillow cases and underwear. Copper sponge filters are being tested for their ability to purify water. I suspect it won't be long before this becomes a new marketing opportunity.

Despite their anti-fungal properties, these elements may also be used in conjunction with fungi. In a novel approach, fungi are being used as templates for stabilizing gold nanoparticles. Under the right conditions, fungi can absorb microscopic metal particles onto their surfaces, creating unusual clusters of nanoparticles, and resulting in metal-fungus hybrids which are able to catalyze certain reactions. It's certainly a novel way of doing bioinorganic chemistry.

Gotta go. I hear some rather vile noises emanating from my son's bedroom.

Full Circle

2008-11-30T22:40:00.001-05:00

Hope everyone had a good Thanksgiving (assuming you live in the US). It was a good time to get together with friends and family.

My last day at work wasn’t as bad as I had expected. Pretty much everyone I knew had taken Wednesday off, so I had done all of my goodbyes the previous day. And since I’ve only been in the new building for about a month, it wasn’t like walking out was all that big a deal. Still, I’ll always remember my last day at work, just as I’ll always remember my first day of work, although for very different reasons. The story I’m about to tell is a lesson on what not to do when leaving school to start a new career….

It was Monday and my PhD still wasn’t finished, despite the fact that it was due in the graduate office on Friday. My thesis advisor had already left town on sabbatical, the movers were showing up in a couple of days, my timetable was inflexible (you’ll see why in a bit), and my fiancée had already made it abundantly clear that I would NOT be missing any of the agreed upon dates. (In the interest of truth, and the fact that my wife might actually read this post, I will point out that this fiancée is not my current wife). The thesis was pretty much done, but I was still fiddling around with the figures, since the thesis examiner was known to be a stickler for thesis formatting rules and if he declined to accept it on Friday, there would be hell to pay.

On Wednesday I discovered my thesis advisor was required to sign my cover page in two different locations. I had had him sign about 10 copies of the cover sheet before he left town (in case I needed backups), but hadn’t noticed the need for the second signature and now he was out of the country. I sweated bullets for a while before I remembered that, as the head of the chemical education program, he had a stamp with his signature on it stored away in his office. After talking with my advisor by phone, and after much practice, I managed to stamp his signature onto the appropriate spot without it obviously appearing to be a stamp. I was hoping the examiner wouldn’t notice.

On Thursday, the movers showed up and after explaining to them which items should be packed and which items should be left alone (I lived in a house with four other people), I went back to working on my thesis. At one point, I left to bring back some fast food, since everything seemed to be going smoothly with the movers. Of course, the instant I left, the movers started packing up my housemates stuff. I spent several hours on Thursday unpacking boxes and returning items which weren’t mine.

After pulling an all-nighter, the thesis was finished by Friday morning and I made all the necessary copies at Kinko’s. I showed up at the thesis examiner’s office with the copies at the designated time, 11:00 am, knowing that the office closed at noon, which meant there would be no time to fix any problems in the thesis should the examiner reject it. I had heard rumors about this guy, who was apparently fond of using rulers to ensure that all formatting rules were followed to the letter.

He accepted the thesis.

Relieved, I drove back to my house, packed up a few things, picked up one of my housemates (who was one of the bridesmaids), and immediately drove 4 hours to southern Illinois for my 5 o’clock wedding rehearsal. Yes, I was trying to squeeze a wedding into the middle of all this. I warned you this was not the way to do things.

Saturday was the wedding, and other than some discomfort in the morning due, I suspect, to a few drinks on Friday night, everything turned out well.

Sunday, picked up a U-Haul trailer and loaded my wife’s things into it.

Monday, left for Detroit, stopping at my house in Urbana to pick up more of my stuff. This made it a 3 day trip, which meant arriving in Detroit on Thursday. Unfortunately, I hadn’t had the time to make hotel reservations, assuming I could just find something on the fly. Not knowing Detroit very well, I ended up stopping at a motel whose reputation turned out to be rather suspect. This suspicion began when, during my check in at the office, some guy appeared, asking if the motel rented rooms by the hour. My suspicion was confirmed when the manager specifically had me park the car so that the doors of the U-Haul would be backed up against a tree, so that no one would be tempted to break open the lock. Needless to say, I must have checked the trailer 10 times over the course of the night.

Friday, I showed up for work on the absolute last day I could have arrived and still been granted vacation days the following year. Thus the rather strict timetable.

Saturday, left for the honeymoon.

That was one hell of a week!

My advice: Make sure to give yourself plenty of time for relaxation before reporting to your new job.

Scary Times, Indeed

2008-11-25T22:07:00.005-05:00

Tomorrow -- the 27th day of the 11th month of the 8th year of the 3rd millennium -- is my last day at work.

It's been one hell of a ride. Layoffs, buyouts, spinoffs, promotions, bankruptcy, blue sky research, product development projects. I've seen good times and bad times. And soon, hopefully, I'll be starting it all over again somewhere else.

One of the things you have to deal with in these situations is understanding why YOU had to be (one of) the sacrificial goats. I know WHY the company had to make deep cuts to survive (at least for a while longer), but as I look around at the people who made it past this round of cuts, I'm not sure why I was one of the chosen. For example, one of my coworkers, who was part of my group before a reorganization in January, is now coordinating projects with the national labs. Those were MY projects before the reorganization. Now I'm not trying to take anything away from her, but these projects simply are not in her area of expertise -- they're in mine. They were given to her simply because they needed to find something for her to do. Had I still been working those projects, I might have survived this rounds of cuts. In fact, I can think of several projects I was working on last year which turned out to be safe harbors. Unfortunately, it was my new project assignment which got axed, and me along with it. Apparently it was a matter of being involved on the wrong project at the wrong time. Ironically, the assignment which got me axed involved more chemistry than I had seen in years.

It's also easy to look around and see people just going through the motions, waiting for retirement to come, and wonder why they weren't approached. Part of that is due to having been in their respective business units for a long time. I was originally a part of the R&D labs, which was broken up about 2 years ago and distributed to various parts of the company. Of the 100 of us originally in the R&D labs, only about 5 of us are now left in the company. I had been warned this summer (by someone with connections inside the company) that we R&Ders had targets painted on our backs, and I guess they were right. Needless to say, the company is going to have a difficult time developing new products in the future.

Low level managers also appeared to be particularly immune to the layoffs, even if the product lines in which they were in charge were being dropped, leaving them with no real purpose in the company. Some of these managers are now spending all their time desperately trying to come up with project areas to justify their continued existence. It's not going to be easy.

All this may sound as though I'm somewhat bitter about the whole mess, and a week or two ago, I probably was. But I've come to realize that I was missing the point. As the company has continued to shrink due to a decline in the automotive sector (and unfortunately that target is still continuing to move downwards), it has been forced to shed many of the product areas in which an inorganic chemist (or any kind of chemist for that matter) would be useful. I look over what's left of the company and realize the company didn't really dump me. It's just that the company I joined many years ago no longer exists.

Miscellaneous Monday

2008-11-17T09:34:00.000-05:00

A few miscellaneous items today.

A week or so ago, our secretary set up a departmental luncheon for the 5 of us in our group who are being "asked" to leave at the end of the month. This morning she came by to tell me that the going away luncheon has been cancelled for now. There were a variety of reasons, including other commitments by at least 2 of the "honorees", but the first reason she mentioned was "a lack of response/participation" from the rest of the department. Nice way to start a day. We'll probably just all get together informally at a bar somewhere instead.
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Ever wonder what might happen if The Matrix was running on Windows XP? Check out this video.
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I guess it's a sign of the financial crisis this country (and the rest of the world) is going through, but I've received 2 of those "help us give you millions of dollars" scam emails in the last week. Is it too much to ask these guys to do spellchecking? It's pretty hard to get really worked up over the prospect of getting free money when you keep hitting misspelled words. Here's an example....

Mr. ABDUL SAAZ a well known Philanthropist, before he died, he made a Will in our law firm stating that Five Million, Two Hundred Thousand British Pond-Stealing should be donated to Ten Philanthropist each.

Of course, some of the misspellings might actually be Freudian Slips. Too funny.

Of course, I take this all back if these guys turn out to be legit.

Glass -- Not Just For Inorganic Chemists!

2008-11-12T15:49:00.006-05:00

Back in the day, we used glass in the lab. Our glassware was glass, our cuvettes were glass, and our eyedroppers were glass. Even our Bunsen burners were glass. And we liked it! Times were good. Having nice, shiny glass equipment on your lab bench made you feel superior to everyone else. And cleaning glass was easy. You just threw everything into a KOH bath for a couple of hours (or weeks) and they came out as good as new.¹ The only reason anyone ever threw glassware away was because of breakage, and even then, if it was only a crack, you kept using it anyway. Or you brought it back to the dorm room/apartment/home office as a showpiece. (Just ask my wife.)

But now you can get almost everything in plastic. Plastic beakers, plastic eyedroppers, plastic volumetric flasks …it’s insidious.² Not only does this practice decrease our valuable reserves of bisphenol A, but it also facilitates the practice of “throwing out” versus “cleaning up”.³ Even worse, it allows the organikers a foothold into the Hallowed Halls of Inorganic chemistry. Dammit! Inorganic reactions should be performed in Inorganic vessels! And silica is about as inorganic as you can get.⁴

But evil always loses out in the end. It’s now been reported that certain organic compounds which tend to leach out of plastic labware can influence (read: screw up) certain experiments. Ha! I always knew those plastic testtubes were releasing nasty organic chemicals! Plastic should only be used to store foods and medicines.

I'll write about this more after I finish repairing a cracked beaker of mine with some epoxy.
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I'd like to take this opportunity to apologize to those readers who have sent me emails asking for information. Although I've been neglecting this site lately due to employment concerns, I've been totally remiss in actually checking out my emails. I'll try to start answering your questions in the future. Thanks again.
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Footnotes – I blame the large number of footnotes on Carbon Based Curiosities and its influence on the blogosphere.

¹KOH/ethanol baths work by slowly dissolving the surface of the glass. It’s an excellent way of dealing with stubborn deposits, although it can trash a fritted glass filter if you leave it in there for too long. There are limitations however. In my attempt to decorate my home office with all sorts of exotic glassware, I’ve discovered that while KOH can make laboratory glassware (borosilicate) look like new, it can mar the finish of regular old antique glass bottles. You have been warned!

²Some of those plastic volumetric flasks have no menisci when holding aqueous solutions. I tell you, that’s damned unnatural.

³I’m actually fairly conflicted about this “throwing out” vs “cleaning up” dilemma. Anyone who knows me knows I’m a hoarder. I rarely throw anything away. Yet, I’m really bad about cleaning, so I tend to find myself surrounded by hoards of dirty, unusable stuff. (Just ask my wife.)

⁴Any evidence (video or otherwise) pertaining to my use of nonglass vessels or equipment is categorically denied.

Attack of the Heavy Metals

2008-11-11T16:04:00.002-05:00

As a (mostly) transition metal chemist, I enjoy heavy metals -- the elements, not the bands. Heavy metals should be a part of any self-respecting chemist’s lab. But they shouldn’t be part of our ecosystem, at least not in the levels associated with human use. The health effects can be serious. Industrial waste, residential garbage (you do recycle your Ni-Cd batteries, don’t you?), and certain pesticides all lead to elevated levels of these elements. I now read that heavy metals are a concern in organically grown foods. Not the first place I would have associated with toxic materials. The whole point of organic growing techniques is to be more biofriendly to the environment by using recycled organic matter instead of synthetic fertilizers. Unfortunately, these organic fertilizers, “composted animal manure, rock phosphates, fish emulsions, guano, wood ashes, etc.” can contain significant levels of these metals. Now this does not necessarily mean that heavy metal concentrations are always higher in organically managed soils, but it has been observed and is a concern. Regulations are tightening and research is continuing, but as we release more and more metals into the environment, the differences between organic and nonorganic farming may become smaller and smaller.

Of course, this is an example of unintentional exposure to heavy metals. Some health practitioners actually want you to ingest heavy metals for your own good. For example, Ayurvedic medicine, based on an ancient practice, uses herbal remedies for a wide variety of illnesses. In the practice of Ayurveda, “…a balance of the metals, including lead, copper, gold, iron, mercury, silver, tin, zinc are considered to be essential for normal functioning of the human body and an important component of good health.” So these metals are often added to Ayurvedic medicines. Unfortunately, there have apparently been reports of heavy metal poisoning related to the use of these medicines, especially in the case of lead. Again, regulations are tightening, but it’s hard to control substances you can buy over the Internet.^*

I think I’ll just stick with playing with my metals in the lab.
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^*Why is the Internet always capitalized? Are there religious connotations here?

Back in the Saddle Again

2008-11-06T23:18:00.002-05:00

Well, it's been harder to get back into the saddle than I originally expected. Once I stopped my regular routine of web surfing to find snippets of chemistry to post on this blog, it's been too easy to keep putting it off “until tomorrow.” It also doesn’t help that every time I sit down in front of the computer, I feel obliged to visit CareerBuild.com or tweak my resume or search for more companies to whom I can send resumes.

While searching the web for hints on job hunting, I ran into an old post from the “Lamentations on Chemistry” blog. The author describes a rather frightening trip to a recruiter’s office. I read it just a few days before my first interview with a head hunter and I was not sure what to expect. It’s an interesting read.

Obligatory chemistry snippet (It’s about damn time!)
I’m sure you’ve all heard the warnings about cell phones and their possible (but unlikely) harmful side effects due to the small amount of electromagnetic radiation they emit. You’ve probably even seen the amusingly bogus “cell phones pop popcorn” videos on Youtube. (My 8 year old daughter has, and she’s at that age where she’s just coming to grips with the idea that not everything you see on TV or the computer is true). But a new concern over cell phones is showing up as nickel in the phones can result in contact dermatitis for those people with nickel allergies.

I hadn’t heard of nickel allergies before this, although apparently it’s been well known that the presence of nickel in jewelry often causes skin problems for a certain percentage of the population. Since my company (used to) manufacture platinum catalysts, I was aware that Pt could have the same effect. (Hmmm, Ni and Pt are both d⁸ metals. Coincidence?) If a worker in the plant began to show signs of a Pt allergy, they were moved to another location. Besides the dermatological problems, Pt allergies can affect the lungs too, producing symptoms rather similar to asthma. So similar, in fact, that one of the PhDs in charge of that catalyst plant theorized that the use of Pt in automotive exhaust catalysts (starting in the 70’s) may explain the rise in asthma cases in the US at the same time. I haven’t seen any of this verified, so take it with a grain of salt.

I’ve enjoyed working with precious metal (Pt, Pd, Rh) salts over the years and I’m fortunate that I have exhibited no such allergies. I would expect it to be rather disappointing to find that you could no longer work in a certain area of chemistry because you were allergic to chemicals.

Reflections on Job Hunting

2008-10-22T21:29:00.002-04:00

Well, it's been exactly 2 weeks since I first got the word about my job status. Since then, I've been sending out resumes, talking to headhunters, scouring the web for job openings in the Detroit area, and networking with people I know. If I didn't have to worry about the future of my family, this would be a pretty exciting time. Surprisingly, I'm fairly upbeat about the whole thing although that might change in a few months if nothing happens. If you've read the intro to this blog, you'll know that I wasn't very happy with the way work had been going. Very little science and even less chemistry. If I land a new job and I'm doing real chemistry again, at roughly the same salary, and without having to move -- it's quite possible this will all have been a blessing. But that's just the optimist in me talking. Or the beer. Not sure which.

Even more surprising is the lack of bitterness over my situation. If the company had been doing well and had just decided to let me go, I'm sure it would be different. But the company is in trouble. Deep trouble. I've never mentioned this before, but my company has been in chapter 11 bankruptcy for about 2 years now. Now originally this was done to allow the company a chance to reorganize itself and shed itself of some money losing contracts and business units. At the time, the future of the company was looking pretty rosy, assuming you were one of the employees who made it through the transition. However, negotiations with labor and the parent company took too long and my company didn't make it out of bankruptcy before the credit crunch hit, and things started going downhill.

As a result, the company was forced to make another round of cuts, much more drastic this time. In this last purge, a lot of really good people were cut. Some of them high performance types who I never would have thought would be released. So my ego didn't take a huge hit. It had nothing to do with performance, but with the job description. Had I started working in the electrochemical sensor group a few months earlier, it might have been someone else in our group who got tapped. So knowing that helps a little.

For that matter, I may still be one of the lucky ones. The severance package is good and I'll be okay for a while. It's generally assumed that the next round of cuts, which might occur early next year based on the company's financials and the general financial state of the country, will have significantly smaller severance packages. At least I have a head start looking for a job in this area.

I was planning on actually discussing chemistry now, but it's late and I'd rather blow up some video game aliens before going to bed.

Enough is Enough!

2008-10-19T21:37:00.003-04:00

OK, I think I've spent long enough away from this blog. Between the big lab move at work and working on my resume at night, I've managed to avoid updating this blog for far too long. Yes, the company still wants me to be responsible for making sure the move to our new labs (as well as various aspects of its construction) goes without a hitch, even though I will probably not be around long enough to actually occupy the new lab site. It's tempting to just say "the hell with it" and let someone else work out all the kinks after I'm gone, but I am good friends with some of the people who are going to be occupying the lab and I have no desire to leave them in the lurch. (I'm sure I will never use the work "lurch" again in my lifetime). It is kind of strange though. I'm one of the few chemists they have left in the division and so it's hard to say how much of the new lab will actually be utilized once I'm gone. But the company has much bigger problems to solve, so I suspect this is a rather minor concern for upper management.

I've begun the process of networking, which means meeting people I haven't talked to for a while and letting them know my situation. For example, on Tuesday, I attended my first Michigan Catalysis Society meeting in over a year. I had stopped going to them when I realized I wasn't really performing much science at work anymore. I had forgotten how much fun it can be to talk to other researchers in my field.

I talked to my first headhunter on Friday, and it was an interesting experience. When I finished my doctorate at Illinois, all I needed to do to find a job was to interview with the recruiters who came to the campus, so I've never had to go out and look for a job before. When you talk to a headhunter, you feel obligated to try and sell yourself to them even though they won't be the one to actually hire you and I found that to be a bit surreal. During the course of the interview, I also began to realize I really wasn't ready to describe myself to potential employers in a coherent fashion yet. I'm working on that now.

So besides being a place to discuss aspects of chemistry, this blog will also be an record of my attempts to find new employment. I hope that part of the blog ends rather quickly.

A New Beginning

2008-10-09T21:42:00.002-04:00

When I started this blog back in January, one of my reasons for doing so was to compensate for the lack of chemistry in my current job. Well, this will soon not be a problem since, as of December 1st, I will no longer be employed at my current job. The severance package is fairly generous, especially considering the financial condition of the company, so I'll be all right in the near term. But I'm not necessarily looking forward to the prospect of finding another job with similar pay at my current location. Life sure is interesting.

The headcount reduction was pretty severe, and a lot of good people were let go. In our group, it came down to a choice between myself and another guy, and we were both fighting over the same position. In its original incarnation, that spot was tailor-made for my skills and experience, but for reasons I'll probably never know, that position was redefined at the last minute and the other guy was chosen, much to the surprise of the rest of the group.

In any case, I should now have more time to devote to this blog. And if anyone is looking for an inorganic chemist in the general Detroit area, be sure to let me know.

Chemist Ken

Interesting Times

2008-09-23T13:17:00.002-04:00

I apologize for not posting anything for the past week, but we are undergoing some major upheavals at work right now. They are downsizing significantly, and the advanced research group is going to get hit. I'll know in about 3 weeks whether I am still employed at this company or not. So my postings may be a bit less frequent for a little while.

Nano-Rods and Sex Videos

2008-09-16T10:39:00.002-04:00

Fortunately, my mother doesn't read this blog, or its titles.

In a continuation of what appears to be my rather unhealthy obsession with nanoparticles, I now read that gold nano-rods are useful in the treatment of cancer. If you are interested in the details, you may read about them here. My reason for mentioning these nano-rods has more to do with their synthesis, which utilizes ionic liquids as the solvent. This results in the formation of nano-rods, as opposed to the usual nano-spheres. [1]

Now ionic liquids aren't all that hard to make -- just heat a salt until it melts. In reality though, the term ionic salts is typically used to indicate salts which are liquids at room temperature, or at least below 100C. Ethylammonium nitrate is one example, with a melting point of 34C, but there are lots of them out there.

I’ve always thought ionic liquids were a pretty cool concept. A fluid made up totally of ions just seems so bizarre. As a class, they tend to have certain properties such as high electrical conductivities, low vapor pressures, and high heat capacities that make them excellent coolants. I had a chance to work on a project focusing on ionic liquids a few years ago, which was tempting since I would have been doing real synthetic chemistry again. However, based on reasons which have nothing to do with science, I chose not to work on that project. A decision which I am now very happy with, for reasons which I won't mention. (Never let it be said that the roads through industrial research careers are any less tricky to navigate than academic career paths.)

The use of ionic liquids as solvents is particularly intriguing. I mean, these liquids are more polar than water! Imagine the opportunities in synthesis. Both inorganic and organic chemists can use them, and anything that brings us closer together isn’t a bad thing.
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Just in case you were disappointed with this post after reading the title, consider David Bradley's take on spray-on condoms. The video is particularly amusing.

[1] I never know whether I should use a hyphen after the term "nano," so I tend to be rather random with its use.

Chemical Symbolism

2008-09-15T13:45:00.001-04:00

So, they are now making nano particles from volcanic lava.

Yes.

From lava.

Really.

When is this nano madness going to end?

Okay, so perhaps I'm exaggerating here a little bit. It would be more correct to say that Dang Sheng Su and his team are making nano particles using volcanic lava. Lava obtained from Mt. Etna in Sicily contains nanosized Fe2O3 particles, which can be reduced to iron nanoparticles at 700C in the presence of hydrogen. These iron particles are apparently good templates for the production of carbon nanotubes and nanofibers when exposed to ethylene and hydrogen at high temperatures.

I know I tend to rag on nano-technology a bit too much on this blog. My first post on nanoparticles wasn't too complimentary. But I've been coming around lately as I read more and more articles on the subject. Much of the research may eventually just turn out to be hype (which can probably be said about any emerging field), but it certainly seems as if there is a lot of potential in this area. Who knows? Maybe I'll be offered a job in nanotechnology sometime in the future. I wouldn't want my views on this blog to limit my opportunities. :)
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Back in 1803, John Dalton developed a series of atomic symbols for some of the known elements at that time. Here is his representation of the table of elements. It cannot be called a periodic table yet since it doesn't demonstrate the periodicity of the elements.

Picture obtained from Wired

Now it's not like there wasn't already a series of symbols for most of these elements already. Alchemists had been using a set of elemental symbols for centuries before Dalton came along, but a lack of standardization was a significant problem, especially since alchemists often used many different symbols for the same element. Certainly, part of the problem was due to the lack of a central authority (IUPAC hadn’t been invented yet). There are at least 20 different versions of the symbol for gold that I know of, and probably a lot more. But the biggest roadblock to standardization among the alchemists was their need for secrecy. Treatises by alchemists were often ambiguous and confusing, apparently to confuse the competition. For example, alchemists often used the term "mercury" for the element mercury, the element gold, the liquid fraction of certain reactions, and various metaphysical concepts such as spiritual goodness. You really need a course to understand what these alchemists were trying to say.

I'm guessing that Dalton was doing his part to disassociate chemistry from the art of alchemy by refusing to use any of the common alchemical symbols of the time. Ironically, his symbol for hydrogen is the same as (one of) the alchemical symbols for gold. Remove the circle from the symbol for phosphorus and you have the alchemical symbol for phosphorus. His symbol for sulfur is the same as the alchemical planetary symbol of earth. Nevertheless, it was a start. It wasn't until Berzelius started using letters based on the Latin version of the element names that everything became manageable. Can you imagine writing out chemical formulas for large organic molecules using Dalton's symbols? If that wouldn't drive you toward Inorganic chemistry, then nothing would. ;P

Xbox's and Cats

2008-09-09T21:33:00.006-04:00

Warning! Very little chemistry in today's post.

How many of you have Xbox 360s? How many of you have had Xbox 360s that have failed? If you're interested, here's a link to an article about what went wrong at Microsoft's Xbox division.
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Yesterday we celebrated the one year anniversary of our cat Sierra. One year ago, we found her as an undernourished 2 month old kitten in my mother-in-law's back yard. Other than destroying a few glass vases, she's turned out to be a great cat. She was apparently weaned off her mother too soon, as her favorite pastime now is to suck on my wife's shirt sleeve whenever she gets a chance (as she is shown doing here).

Several months ago there was an article on the blackest black pigment ever produced, using carbon nanotubes (IIRC). Back when Sierra was a kitten, before her coat became shiny, she probably could have challenged that claim. She was an absolute black hole as far as absorbing visible light. Taking photographs was almost pointless since all you'd see was an amorphous black mass, occasionally with two eyes showing, which let you know which end you were looking at.

Happy first birthday, Sierra!

Nano-gold Catalysts

2008-09-08T21:40:00.005-04:00

Reports of nano-gold and its use as a catalytic material are beginning to pile up. Last week I mentioned nanogold particles in stained glass windows and their ability to oxidize organic pollutants. This week, two more articles showed up, here and here. Hmmm…. seems like we’re beginning to reach a critical mass here. Pretty good for a metal that hasn’t been considered a particularly good catalyst over the years. Perhaps I'll start paying more attention to this area. I’ve read articles about nano-particle based catalysts in the past and have generally been underwhelmed, but nano-gold catalysts may be about to change that view. And that’s because of two words that are often found in these reports.

Room temperature.

Or at least, low temperature.

The obvious reason for using nano-particles is their much larger surface area to mass ratio. Higher surface areas generally mean better catalysts, so the drive to make smaller and smaller catalyst particles has been going on for decades. Back before “nano” became a marketing term, I recall at least one set of researchers making platinum nano-particle catalysts to improve the efficiencies of automotive exhaust catalysts. They succeeded, but unfortunately, at the high operating temperatures (generally above 400^oC) to which these catalysts were subjected, the platinum nano-particles tended to move around and coalesce into much larger particles, losing much of their surface area and eventually not looking all that different from more crudely prepared catalysts. In fact, with these types of catalysts, research is focused less on the catalyst itself and more on the substrate which supports the catalyst -- changing its properties so as to limit the movement of the catalyst particles. This is always a bit of a balancing act since too much interaction between the catalyst and substrate can change the properties of the catalyst in undesirable ways. But if the reactions to be catalyzed take place near room temperature, or at least at lower temperatures, you stand a much better chance of maintaining the catalyst nanoparticles and hence their benefits.

Gold has traditionally been the forgotten metal, with all catalyst discussion centering on its neighbors on the periodic table (Pt, Pd, Rh, Re, Ru, and Ag). That looks like it's about to change. The big question to be answered: Why are nanogold particles so much better than bulk gold? Here are some possibilities to consider.

1. Larger surface areas. Well yes, you would expect some benefit here, but gold has been so unremarkable as a catalyst, I don’t believe a simple increase of surface area would account for this big of an effect. If it were that easy, everyone would just have dumped more gold into their catalyst formulations in order to increase the available surface area.

2. More defect sites. In many cases, catalysis only occurs at specific sites on the catalyst surface, such as the so-called "steps" as shown in the figure below. Perhaps nano-gold particles naturally have more of these locations.

3. More of the appropriate crystal faces. Different lattice faces such as (111) or (100) often have significantly different catalytic rate constants. See figure above. Perhaps nano-gold particles have more of the correct lattice orientations at the defect sites than bulk gold.

4. Different surface oxide properties. One of the reasons metals like Pt and Rh make such good catalysts is their ability to maintain surfaces which are relatively clean of oxygen atoms. Whereas the early transition metals tend to form oxides, the late transition metals favor the metallic state. Heat vanadium or molybdenum in air and you form the oxides. Heat platinum or its salts in air and you wind up with platinum metal. Keeping the surface free of oxygen atoms makes the metal more available for catalyzing the desired reactions. Perhaps smaller gold particles tend to have less oxygen on their surface.

Figure obtained from http://www.pnas.org/content/103/28/10577.full.pdf

Fall and Chemistry

2008-09-07T23:02:00.002-04:00

It's September and that means the fall semester has begun in most universities. Of course, this also means the start of chemistry classes. If you are currently employed in industry, like me, then you probably didn’t notice this momentous event, at least until you realized the college football season had begun. If you're an undergraduate, or perhaps a first or second year graduate student, you probably noticed it a lot, especially as you paid for this semester's chemistry textbooks. Once they're done with classes, however, grad students usually don't pay much attention to the beginning of semesters either, unless they are required to teach undergraduate courses. Once they make the switch to full research mode, the ebb and flow of university life is often lost to them. I've known grad students who were so oblivious to the change of semesters, they would often wonder out loud why parking was suddenly so difficult to find.

When I was a graduate student at the University of Illinois at Champaign-Urbana, however, it was always easy to notice the start of the fall semester, no matter how deeply involved you were in your research. It wasn’t football fever, or seeing all the wide-eyed newbies milling around in herds, or even the sudden lack of parking. The most obvious sign that classes were about to begin in Urbana was: after going through the entire summer with absolutely no road construction projects, suddenly seeing 4 or 5 road projects spring up around campus during the week before classes. Try to imagine 30,000 students showing up at the same time in cars and vans loaded with all the necessities of life (for a university student) and finding many of the roads blocked off. Seriously, this happened every year I was there and I have no reason to believe that tradition still doesn’t occur today. Correct me if I’m wrong.

By the way, the Illinois football team lost their opener to Missouri. I’m not too particularly bummed out about that since Missouri is where I received my B.S. and M.S. in chemistry. Talk about a no lose situation -- one of my alma mater’s had to win.

Laxatives and Boredom

2008-09-05T13:49:00.003-04:00

Catchy title, huh?

My daughter recently discovered she has an in-grown toenail and the doctor recommended she soak her foot in a warm Epsom salt bath. So of course she asked us what the Epsom salts did. My wife thought Epsom salts (essentially MgSO4) kept the bath warm longer, but that didn’t seem very likely to me since you could get the same effect from cheaper salts like NaCl. So of course, I had to look it up.

Apparently, MgSO4 absorbs through the skin and does reduce inflammation. It acts as a calcium channel blocker and relaxes the smooth muscle groups (blood vessel walls, for example). If you absorb enough of it, it can lower your blood pressure. If you consume enough magnesium (for example, Milk of Magnesia or Maalox) you’ll discover it behaves as a laxative. If you consume MgSO4, you'll discover it is a very good laxative since the sulfate group enhances the effect.

Irrelevant fact: MgSO4 was given the name Epsom salts in honor of the town in which it was originally discovered back in the 1500s -- Epsom, England.
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I was looking over the statistics for this website today and noticed that while traffic has been slowly rising over the past several months, a very noticeable periodicity has begun developing. It’s a weekly cycle, with a minimum on the weekends (no surprise there), and (almost) always peaking on Wednesdays. It’s a triangle waveform, with Tuesdays and Thursday roughly equal but lower, and Fridays and Mondays equal but lower still. Not the distribution I would have expected. Does this represent middle of the week inquisitiveness, restlessness or boredom? Perhaps I should save my best posts for Tuesday evening?

Question of the day: Do you find your blog reading habits to be that structured?

Journal Backlog

2008-09-03T21:22:00.006-04:00

One of the reasons I started this blog was to bring myself back to feeling like a real chemist again. I do not work at a chemical company, I work at a manufacturing company. There aren't many chemists here and there is no library of chemical journals. Only on rare occasions can I justify going to chemical meetings and I just don't do that much wet chemistry anymore. One of the purposes of this blog was to force me to read the literature again, in order to know what's going on out there in the world of chemistry. So early this year I started subscribing to various journal alert emails. Every time a new issue is released I get an email with all the article titles along with links to their abstracts. Of course, if I find an article I'm interested in, I still have to drive to a nearby university in order to actually read it, but it's a start.

Unfortunately, I have not been very diligent with these alerts. At first, I read them immediately upon arrival, but as various projects began to heat up, I started putting off reading them until later. Eventually I created a "Stuff to Read" folder to store the emails to prevent them from being lost forever. Unfortunately it's gotten to the point where I immediately move them to this folder the instant they show up - whether I'm busy or not. Well today I actually opened the folder and was embarrassed to discover I had 250 unopened email alerts. Perhaps I need to cut back on the number of journals I want to track. Then again, as I think back to grad school, perhaps I wasn't all that good about reading journals then either. Does anyone else have problems keeping up with their journals?

Grad students, be sure to take advantage of your library while you've got it. You may not have it forever.

Edit: I woke up this morning to find 5 more alerts in my mailbox. Crap! I'll never catch up.

MeatWater

2008-09-02T22:07:00.004-04:00

Sometimes (like right now), it's late, I'm tired, and I don't have anything relevant to talk about. In that case, I basically have 3 choices:

Choice #1. I can forget about posting tonight and hope that inspiration occurs within the next 24 hours. This is usually the easiest thing to do.

Choice #2. I can imitate those horrible sitcom episodes where the actors sit around and "recall" things that happened in previous episodes so that 25 minutes of old footage can be used to create a 30 minute show. In my case, I would craftily sprinkle links to some of my old blog posts in sentences that had nothing to do those posts. But since that would be demeaning to you, the reader, I refuse to do that.

Choice #3. I can point you to an funny website and hope you are amused. I'm sure you've heard of vitamin water, right? Bottled water with a few vitamins added for marketing purposes? Well, we all need proteins too, so now we have MeatWater. Available in 18 flavors (bacon was just added), now you can get all your amino acids while you're hydrating yourself. Isn't marketing wonderful?

BTW, just in case you were beginning to wonder just how pathetic the human race was becoming, I should point out that this website is a fake.

Old Memories

2008-09-02T10:56:00.001-04:00

I hope everyone enjoyed the Labor Day weekend. We spent a lot of it cleaning out our basement, which translated into throwing out a lot of old stuff, most of it mine, and much of it items I didn't even remember having in the first place. One of the items was a desk that I've had since grad school in Missouri. No one was using it anymore, so we gave it to my wife's nephew who is beginning his freshman year at Lawrence Tech, so it's going to a good home. I originally bought the desk from another student who was leaving Missouri after graduating with a B.S. in chemistry. It was painted a rather bizarre looking green color, which meant no one other than another grad student would have felt comfortable bringing it back to their apartment.

While emptying the drawers, I came across some old pictures I had taken early in grad school - in particular, pictures of my old chemistry lab. They certainly brought back some (mostly) fond memories. There were pictures of my old chemistry building, my lab, and the old Nuclide isotope ratio mass spectrometer with which I performed most of my undergraduate and master's thesis work (and which now looks like a prop from a "B" science fiction movie).

Schlundt Hall.

This was the building where I spent much of my life during grad school in Missouri. Schlundt Hall was known as the "old chem building" as opposed to the flashier new chemistry building which housed the organic, analytical, biochemical, and some of the other inorganic groups. Home to the main lecture hall and most of the freshman labs, it also contained several labs in the basement which were under the control of my advisor, R. Kent Murmann, who had no problem setting up undergraduate students in this rooms. Although Schlundt Hall was often looked down upon by some residents of the newer building, it just oozed with atmosphere (the good kind, not the kind generated by chemicals, ... at least I hope). It had that old style fortress/castle look to its architecture, including the crenellations (the notches in the wall from which archers could fire) on the roof (upon which you could walk if you knew how to pick the door locks -- which we did). This place could have been Hogwarts -- minus the magic and about half of the deathtraps. And since we were the only group in that part of the building, we basically had free reign to do as we wished. Perhaps I'll reveal some of the things that went on in that building at night in another post. In any case, the memories were great.

My Desk

If you think this desk is a little messy, you should have seen it before it was cleaned. Amanda over at "A Chemist's Laboratory Notebook" shows pictures of her desk at various times, but believe me, even 2 weeks before her thesis defense, her desk still looked better than mine on average. God knows what most of that stuff on my desk is. Yes, that is a can of diethyl ether sitting on the desk. Having chemicals occupying much of the desktop seemed normal at the time. I can only hope I didn't eat food at my desk very often.

My Lab Bench

What can I say? I can only imagine what the bench looked like before I cleaned it up. The "Accidents Before They Happen" poster taped to the wall was probably placed there by my advisor. I suppose I could have a contest to see how many safety violations could be found in this picture, but that would only destroy the romance of the lab. Damn, I had access to a lot of chemicals back then. I'm lucky if I have more than 10 in my current lab at work. I'm definitely bummed about that.

If you are a graduate student, or an undergraduate with a lab, I suggest you take pictures of it before you leave. You'll be glad you did later.

We're Moving.... Sometime.... Maybe.....

2008-08-28T21:34:00.005-04:00

Today we received word that our lab will be moving to the new research site at the end of October. Even though this pronouncement was delivered by upper management, it can be considered nothing more than a rumor until it actually happens. Too many unknowns exist for anyone to even guess at our move date. For one thing, the construction crews haven't even begun work on our lab yet. We are part of the third (and final) phase in the rollout plan and they haven't even finished the first two phases yet. As a further complication, our current building is being taken over by another set of tenants in the near future. If they show up early, we may find ourselves being thrown out early. And of course, knowing how this company works, it would not be surprising if some clueless upper manager somewhere arbitrarily changes the move date with little regard for how it might affect our projects.

I've talked about our move before, and while it will be great to get all of us (chemists, physicists, engineers, purchasing, IT, marketing, etc.) together in one building, I'm still going to have to endure some pain before everything is settled. Our group is not the only group waiting for their new labs to be finished. But those groups have not been given permission to stay in their labs any longer, so they will be moving into our already crowded lab for a few months.

Since I do stop over at the new location occasionally, I've begun to notice some of the annoyances that the new place will have to offer. First, while remodeling the building for our use, it was decided that a wireless intranet was the way to go. We still have network jacks at all our desks, but that's about it. None of the conference rooms had internet jacks installed. This isn't a problem if your laptop is wireless, but mine isn't. Nothing can quite describe the pure horror of having to attend a group meeting without having access to the internet. What the hell are we supposed to do during the boring parts of the meeting? Everyone else uses these meetings to go through their mail, read Dilbert cartoons, and check stock prices. It's just not fair! I've ordered a new laptop computer so hopefully this will not a problem by the time I move to the new location.

Parking is also going to be a problem at the new site. It's not like there aren't plenty of spaces available, it's just a matter of how far away you'll be from the building when you find a spot. This can be a significant issue during Michigan winters.

You have to use your magnetic security badges to unlock doors in order to go anywhere in the new building. No more just sticking it in your pocket and leaving it there all day.

Finally, there is this one guy at the main desk who insists on checking my laptop every time I leave in the evening. He actually checks the serial number on the bottom of the laptop with the number on my security badge. It's not like he hasn't seen me before with a laptop, and it's not like it would take me more than 5 minutes to fake the serial number on the laptop, but he insists on doing it every time. I can bypass this problem by exiting through one of the unmanned, security badge accessible side exits, but that puts me a lot farther from my car and will not be a favored option during the winter.

Additional note: Our old location is located within three miles of the four plant nurseries where I buy most of the flowers I plant every year. The new site has no nurseries anywhere near it. Damn! Obligatory garden picture follows:

Golden Health

2008-08-27T23:15:00.002-04:00

Gold has been used for medicinal purposes since the time of the Romans. Rightly or wrongly, gold was often used as a medical treatment for a variety of conditions. It does appear to have anti-bacterial properties, much like silver. In medieval Europe, pills were often coated with gold to "enhance" the benefits of the medicine. Paracelsus, the alchemist, developed a solution of colloidal gold which he named "Aurum Potable". He considered it a powerful elixer capable of curing all sorts of ills.

In recent years, gold has experienced a bit of a renaissance in the form of nano-particles. Gold nano-particles are being used for drug delivery systems, biosensors, optical devices, and catalysts, among other things. It's hard to get through a chemistry journal without seeing at least on paper on nano-gold. In retrospect, gold nano-particles aren't really all that new. First of all, they apparently already existed in nature. They were also used by the Romans to create red stained glass. In bulk form, gold is yellowish since it reflects light at the blue end of the spectrum less efficiently than other colors. However, if the size of the gold particles is significantly smaller than the wavelength of visible light, new interactions occur between the light and the gold surface, resulting in a red color. In aqueous suspensions, purple and yellow colors can also be obtained if the particles are allowed to aggregate. In fact, Paracelsus's purple "Aurum Potable" was a simple suspension of gold nano-particles.

As you can imagine, colloidal gold is now available all over the net (for example, here and here) for boosting your physical and mental health. Don't feel like drinking gold? No worries. They also sell nano-silver, nano-copper, nano-platinum, nano-palladium, nano-iridium, nano-titanium, and nano-zinc too.

Why am I mentioning gold's supposed health benefits? Apparently the Romans were on to something back in the day since it turns out their gold nano-particle based stained glass windows are good at removing volatile organic compounds from the air. Will we be seeing gold-based air purifiers in the stores soon? I can only imagine what the web marketeers are going to do with this information.

Hooray! Aqueous Transition Metal Chemistry Talks

2008-08-21T22:18:00.007-04:00

I really miss going to ACS meetings, but with chemistry not being as big a focus at my company anymore, it can be difficult to justify (to upper management) the expense of going to one unless there is a session directly related to my current project. I attended a session on reforming catalysts several years ago, but that’s been it for a while. Besides, my true love is aqueous transition metal chemistry and those types of talks can be few and far between. So imagine my surprise and delight when I ran across blogs discussing, not one, but two such talks being presented at this week’s national ACS meeting.

The first talk was mentioned on the Chemistry Blog, concerning a study to use chelating agents like EDDA to extract actinides from nuclear waste. YES! Good, old-fashioned aqueous transition metal chemistry. Okay, actinides aren't strictly transition metals, but they're close enough. I did find it amusing when Mitch wrote "These types of systems look promising and are a nice upgrade over traditional old-school extractors like tributylphosphate(TBP)." Any reference to classic chelating agents as "new-school" is music to my ears. To be honest though, I would have thought that these chelators, especially EDDA, would have been tested for this application a long time ago. At least it shows there are still applications for this type of chemistry yet to be discovered.

The second talk involved the use of Fe-TAML complexes to facilitate the oxidation of organic pollutants by hydrogen peroxide. Apparently these complexes are good mimcs of peroxidase enzymes. Here is the structure of the compound taken from the Collins group website:

Although I haven't had the chance to read the mechanistic and kinetic work on these reactions yet, this seems like a classic example of the TAML group basically locking the Fe into a square planar configuration and keeping it stable while it’s shuttling back and forth between the +2 and +3 states as it facilitates the transfer of electrons between the H2O2 and the target molecule. I've always had a soft spot for chelating agents that lock themselves around metals in tight, specific configurations, significantly changing the metal's properties in the process. My first undergraduate project used an amine oxime to wrap itself around cobalt in a manner resembling the structure of cobalamin (B12 vitamin). Classic aqueous transition metal chemistry. It brings a tear to my eye.

The Value of Toxic Metals

2008-08-19T17:08:00.008-04:00

These's a body of water in Montana known as the Berkeley Pit. This lake is a remnant of an old open-pit copper mine that closed down in 1982 when it was no longer profitable to operate. It has since filled with water, about 37 billion gallons worth, and that's when the real chemistry began. Pyrites and other sulfides dissolved in the water and oxidized, forming sulfuric acid, and lowering the pH of the water to less than 3. This led to the steady leeching of metals out of the surrounding rocks, and after 25 years the Berkeley "Lake" has high levels of arsenic, lead, zinc, manganese, iron, copper, aluminum, and cadmium. It's a place only an inorganic chemist could love. It's also a part of one of the largest Superfund sites in the U.S. Nothing lives there - no fish, no birds, no plants - it's a dead zone, or at least that's what everybody thought. In 1995, someone spotted some green slime on the surface of the lake, which turned out to be a form of green algae.

Organisms which manage to survive extremely harsh conditions are called extremophiles. They have been found under the ice in the Arctic, around deep sea vents, and in the boiling water of hot springs. Their ability to survive these conditions makes them of interest to biologists. In particular, many extremophiles demonstrate a superior ability to repair their DNA, which makes them of great interest to cancer researchers. Andrea and Don Stierle have been studying the organisms which have been living in the pit, looking for new compounds which may have anti-cancer activity. And they have been successful, having discovered berkeleydione, berkeleytrione, and berkeley acid, all of which have shown anti-cancer activity. The structures for berkeleydione and berkeleytrione are shown below.

Thought #1:
Makes you look at toxic metals in the environment a little differently now, doesn't it? Perhaps we should be harvesting more of the toxic waste dumps we have created over the years. It could be one of this country's biggest resources.

Thought #2:
Microorganisms are better at making new and novel organic compounds than grad students. Soon, the only reason why faculty members will continue to hire grad students instead of microorganisms will be because grad students are usually paid less than what microorganisms would accept.

Disappearing Elements? - Part III

2008-08-17T22:43:00.000-04:00

In what is shaping up to be a recurring theme, there is yet another report warning of the possible future scarcity of an element. This time it's lithium.

The biggest sources of lithium are salt pans and salt lake deposits, mostly in Chile and Argentina. There is also a large, relatively untapped reserve of lithium salt is in the Bolivia salt pans. The Bolivian reserves are thought to contain 5.4 million tonnes of lithium (nearly 50 per cent of the global lithium salt reserves). Since the annual worldwide production of lithium is about 70,000 tonnes (lithium carbonate), this would seem to indicate we have plenty of lithium for the near future, assuming that demand does not significantly increase. Unfortunately, demand may be about to increase drastically. Lithium ion batteries are becoming all the rage, especially as automakers attempt to mass produce hybrid and electric vehicles.

According to William Tahil, the report's author: "to make 60 million plug-in hybrid vehicles a year containing a small lithium-ion battery would require 420,000 tonnes of lithium carbonate – or six times the current global production annually. But in reality, you'd want a decent-sized battery, so it's more likely you'd have to increase global production 10-fold. And this excludes the demand for lithium in portable electronics." At that rate, lithium is going to run out a lot more quickly.

However, this is not a universally accepted opinion. Keith Evans, a geologist with some expertise in lithium mining, disputes Tahil's conclusions. Evans believes that the available lithium reserves are much larger. His critique of Tahil's report is given here, and additional details can be found at his blog, which is named Lithium Abundance.

I don't use lithium very much in the lab, although I have occasionally used LiAlH4 and LiBH4. Still, I would be rather bummed out if we ever ran out of lithium, or any element for that matter. Let's hope Evans is correct.
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In more lighthearted news, John Swain of Northeastern university has a video demonstrating that the iron which is used to enrich cereals like Total is actually in the metallic form. The link to the story is here and a link to a commercial free version of the video is here. I assume this isn't some sort of joke.

Chemistry Journalism?

2008-08-13T19:46:00.009-04:00

I try to spend some time every day browsing through the various science reporting websites so as to receive my daily dose of science. I generally find them informative, but today I was greatly disappointed with the level of their quality. Science Daily reported the discovery of “an unusual molecule that is essential to the atmosphere's ability to break down pollutants, especially the compounds that cause acid rain.” "Okay," I thought, "that sounds interesting. I'll check it out." So I read through the entire article, several times, looking for the new molecule until I finally realized the molecule was never identified.

"Okay," I thought, "the writer screwed up. I'll just google some other articles."

Googling did indeed reveal many, many other sites which had covered this story. Unfortunately, it quickly became obvious that other sites weren't describing the molecule either. In fact, the articles were all identical copies of the original Purdue press release. No additional explanations, no deep dives into the subject matter, nothing but simple copying and pasting.

Now that is just plain laziness. I realize the internet is one huge morass of plagiarism -- it's not uncommon to find the same page duplicated over and over again when googling -- but I expect a little more from science news sites that are updated on a daily basis. At the end of the Science Daily article it reads: "Adapted from materials provided by Purdue University." By adapt, I assume they mean reformatted.

Of course, all this occurred because the Purdue press release had failed to identify the molecule. A full color ball and stick model of the molecule was presented, which the science sites dutifully reproduced, but there was a problem. I present the figure and its caption here.

Image caption: Scientists at Purdue and Pennsylvania universities have discovered an atmospheric molecule that is essential to the breakdown of pollutants in the atmosphere. The molecule, which had not been seen before, is unusual because it has two hydrogen bonds. This image shows the structure of the molecule, with the blue ball being a nitrogen atom, red representing hydrogen atoms, white representing oxygen atoms, and the yellow clouds showing the location of the double hydrogen bonds. (Purdue News Service image/Joseph Francisco)

So the molecule was O-H-NH2? That sure looks like one hell of a reactive molecule. Who cares about a double hydrogen bond? We have a hydrogen with two covalent bonds -- a much bigger story. Or maybe the person writing the caption just got the colors for hydrogen and oxygen switched. I was able to figure out the molecule's identity by looking at the title of the abstract tacked on at the end of the press release. If any of the website writers had actually bothered to read this press release while pasting, this mistake would have easily been caught. BTW, the new molecule is an HONO2 + OH moiety, held together by hydrogen bonding.

I'm not trying to dump on Purdue here, mistakes like this can happen. I’m just disappointed that none of the science sites I frequent picked up on it.

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Note: while writing this I noticed that the Science Daily report did list a link to the paper which included the terms OH and HONO2, so it wasn't totally necessary to go to the Purdue site to figure out what was going on.

Humility is Good for the Soul

2008-08-12T22:16:00.002-04:00

One of the reasons I started this blog was to sharpen my chemical skills -- skills which have been steadily declining over the years as my job has required less and less chemistry. I just played the “Can You Name the Elements in the Periodic Table in 15 Minutes” game and was reminded of just how little attention I’ve paid to the periodic table in the last 10 years. I expected that my score was going to be rather poor, and I was not disappointed. I only remembered 70% of the elements. I knew I’d have trouble with the actinides and lanthanides, but I also had trouble with the heavier main group elements. And even though I nailed all the transition metals, it required an embarrassingly long time -- embarrassing because transition metals are supposed to be my area of expertise. And it hasn't been that long since I've worked with the precious metals (Pt, Pd, etc.), so why did it take so long to remember rhodium, dammit? That’s pathetic. I also missed a few elements because I couldn’t remember how to spell them. Damn that praseodymium. Where’s the spell checker when you need one? Try the game at your own risk.

Maltese Water Problems

2008-08-12T16:43:00.000-04:00

Reverse osmosis is the technique generally used for the desalination of seawater. Unfortunately, the polyamide-based membranes typically used in these processes are attacked by chlorine, which complicates the purification process (meaning more expensive). Polysulfone-based membranes are resistant to chlorine, but their hydrophobicity means that water does not move well through them. Extra hydrophilic sulfone groups can be added to the polymer, but they tend to attach to the least stable sites, which limits their effectiveness. Now, two research groups have combined to solve these problems -- by using the remarkably simple idea of adding the polysulfone groups to the original monomers before polymerization.

Reaction diagram obtained from patent application

Considering the lack of fresh water at locations around the world, anything that can help lower the cost of desalination can be a big deal. As I read this article, one country immediately came to mind -- Malta. Located 50 miles south of Sicily, the islands of Malta are the home country of my wife's parents. As a result, my wife and I have already visited Malta three times in the past 12 years. And believe me – it is hot! Since I think Michigan summers are too hot, you can only imagine what I think about our summer visits to Malta. Here is a family picture taken last summer in Malta.

Not a lot of greenery around. Mars probably has more water in the soil than Malta. Notice my daughter's T-shirt. Never too early to start influencing them.

It turns out that due to the quantity and quality of their beaches, Malta is a common vacation spot for many Europeans, especially the British and Germans, who tend to spend all day at the beach before showing up later in the evening looking remarkably like broiled lobsters. The water quality was fine 12 years ago during our first visit, but the influx of tourists, along with an increased demand for water by the local residents, has apparently stressed the desalination plants. 5 years ago, during our second trip to Malta, the water was really too salty to drink and we essentially lived off of bottled water for two weeks. Last summer, although the water was getting better, we still stuck with the bottled water. It's weird being surrounded by all that water and yet having to import water from the mainland. I hope this new membrane will allow Malta to build a few more desalination plants before our next visit.

Textbooks Are Becoming Old School

2008-08-07T16:53:00.003-04:00

Question. How many of you still have your old chemistry (or physics or whatever) textbooks from your undergraduate years? I think I still have nearly all of mine. And although I'm sure this is at least partly due to my being a packrat who can't throw anything away, it's also due to the fact that I like books. I may still go to the web first if I need some piece of information, but sometimes it's easier to go back to your textbooks for more detailed explanations. Besides, there is just an intrinsically good feeling when holding a book in your hands. But after reading this article, I'm beginning to wonder how much longer this trend will continue. Apparently, it's becoming just as easy to download textbooks illegally as it is to download ripped music and warez. And publishers are beginning to react in various ways. Unfortunately, one of their strategies is to offer the texts in ebook format, with subscriptions that run out at the end of the semester. So much for using that text as a reference a year from now.

Publishers, please let us keep our paper-based books!

BTW, this only applies to real textbooks. Textbooks for classes like psychology or sociology can be burned or thrown into an acid bath for all I care.

MIT Propaganda Machine

2008-08-06T23:35:00.002-04:00

No doubt, many of you have heard of the recent “MIT Breakthrough”^TM which provides a dramatic new way to store solar energy. Using a simple catalyst consisting of cobalt and phosphate, Daniel Nocera has supposedly removed the biggest road block holding back mass utilization of solar power. This story has been making its way through the web and the blogosphere for several days now and since I’m not an electrochemist, I’m not sure how much more I could add. However, my first reaction after reading the article was a sense of annoyance, and I found myself becoming more irked every time I read another article on the “breakthrough.” Part of my irkness^TM was due to the authors themselves. I’m not sure how much information MIT released to the press, but several of the writers really had no clue about what the invention really was or why it was novel. Perhaps I'm a poor reader, but it required reading several articles before I was even sure exactly what Nocera had and had not done.

Irksome point #1. The constant references to solar energy, despite the fact that this catalyst has nothing to do with solar energy per se. The invention makes the electrolysis of water more efficient, nothing more. Nocera hopes that one day his invention may work in conjunction with solar power, using electrolytically generated hydrogen as an energy storage material, but right now, it doesn’t really have that much to do with solar energy, despite MIT's press release.

Irksome point #2. Many of the article writers appeared to be unfamiliar with the process of electrolysis, marveling at the novelty of being able to electrolyze water at room temperature. Hmmmm, I vaguely seem to recall hooking up a battery to salt water back in high school. Why wasn’t I referenced in these articles? The problem is that the efficiency of electrolysis is poor under these conditions, which I believe is due to the overpotential required when generating gases. (Please let me know if I am mistaken here.) Commercial electrolysis devices have been around for awhile, although to keep the efficiencies high, they are often run at high temperatures and pressures, using expensive electrodes and basic solutions. The novelty of Nocera’s breakthrough is that the cobalt-phosphate material allows for higher efficiencies at room temperature using cheaper materials.

Irksome point #3. The Scientific American writer who referred to both cobalt and phosphate as metals needs a refresher course in chemistry.

Irksome point #4. The MIT press machine set off the BS (Blatant Statement) meter way too often for my taste. Nocera didn’t do himself any favors either, with quotes like:

“This is the nirvana of what we've been talking about for years"

“I've gotten rid of all the goddamn [power] grids."
Probably not during your lifetime, Daniel.

"Solar power has always been a limited, far-off solution. Now we can seriously think about solar power as unlimited and soon."
Sorry, but as I understand it, one of the big problems with solar power is the low conversion efficiency of sunlight into electricity. This invention does nothing to solve that problem.

Irksome point #5. I don’t really have one, but I really wanted to use “irk” as many times as possible. I’ll probably never use the word again.

Snarkier blog posts on this subject can be found here and here.

Aqueous Chemistry Rules!

2008-07-29T22:45:00.006-04:00

Apparently, polyoxometalates have been found to be "very powerful inhibitors of a specific protein kinase, CK2, an enzyme that is overactive in a number of cancers." I say apparently, since it was reported in the journal "Chemistry and Biology," a journal to which I do not have access. I only know of the study because of this press release. Polyoxometalates are large anionic clusters generally consisting of transition metals and oxygen. A good description can be found here. This study is of particular interest to me since I have worked with polyoxometalates of V, Mo, and W in the past. I admit to having lost touch with them over the years, mostly because my work at that time involved aqueous polymetalates (I love aqueous chemistry!) and subsequent research on polymetalates had begun turning to derivatives which were only soluble in organic solvents. So it was with some delight that I discovered that aqueous polyoxometalates had reappeared in the literature. Unfortunately, the press release gives very few details about the particular polyoxometalates involved or what kind of chemistry is occurring. In fact, I am only assuming that these are aqueous species since they are being used in biological systems. In any case, since aqueous chemists seem to be vastly outnumbered by non-aqueous chemists (I was definitely in the minority in the U of Illinois Inorganic Chemistry department), I am always happy to see a paper on aqueous chemistry that is at least somewhat mainstream.

Are there any aqueous inorganic chemists out there reading this blog?
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My family and I will be leaving tomorrow to visit my parents in Springfield, Missouri for 5 days. I've talked about Springfield before, so it's always a fun trip, but I won't be updating the blog until next week. In the meantime, here is the previously promised picture of my garden (or at least a small part of it).

Wii

2008-07-25T23:56:00.003-04:00

Well, we finally broke down and bought a Nintendo Wii last weekend. "Broke down" probably isn't the most accurate description since everyone in the family has wanted one since last Christmas. It's just that we had originally planned to wait until the fall. But my wife discovered that a supply had arrived at the local Target and so I was dispatched to grab one before they disappeared. This is our first game console. I spend all my gaming time playing on the PC, in part because I really don't like gamepads. I'll take a mouse/keyboard combo everytime (old school?). But I think the Wii might be a good way for me to become proficient with a gamepad.

Anyway, the kids love it. And my six year old son quickly discovered you don't have to be near the TV to play. The sensor system can pick up the signals from the Wiimote all over our house, so he runs around various rooms throughout the house playing games like "bowling" with no video feedback. It's a little disheartening to watch him get a strike when he's somewhere in the basement while you're standing right there in front of the TV and still haven't gotten a strike all game. Annoyingly, he actually has the nerve to get upset when he loses the game. Oh well, in the meantime, I'll be looking for some good chemistry-based games.

Non-Standard Laboratory Equipment

2008-07-24T00:11:00.003-04:00

Over at The Chem Blog, Kyle describes his development of a photochemical light source built out of items purchased at the local Wal-Mart. I'm sure we all have stories about the ingenious use of items obtained from outside the laboratory environment. Years ago, when I was working on "Better Ceramics Through Chemistry" projects in the metallurgy department (yes, I was exiled to the metallurgy department for a while. I'll discuss that in more detail at another time.), my co-worker used a wet isostatic press to compress ceramic materials in preparation for high temperature sintering. Basically, wet isostatic pressing consists of sealing the material in a flexible waterproof container, removing as much air as possible from that container, placing it into the oil reservoir of the press, and then letting the press pressurize the oil until the ceramic material is compacted to the desired density. Unable to find a suitable container from the usual lab catalogs, he eventually took a trip to the drugstore and bought some condoms. Apparently they worked like a charm in the isostatic press. Unfortunately, he ended up paying for them out of his own pocket since he didn't have the nerve to submit an expense report to upper management.

Where Has All the Ammonia Gone?

2008-07-21T22:25:00.004-04:00

This weekend, I was filling a bottle with some copper nitrate crystals for display in my office at home. They are a really beautiful shade of blue and as long time readers of this blog know, I love bright, pretty colors. My daughter wanted to dissolve a few crystals in water to make a blue solution, and so we did, but the solution was disappointingly pale. Sure that I could solve the problem, I went to the laundry room where we keep many of our household cleaners, hoping to find some ammonia which we could add, since Cu((NH₃)₆²⁺ is much more intensely colored. To my dismay, I found that we do not carry ammonia any longer (assuming we ever did). So I rummaged through the various cleaners, sure that at least one of them was ammonia-based. The glass cleaning solution looked promising, but the label stated "ammonia free formula" so that was out. Finally I found some Windex with "Ammonia D," what ever that is, and tried adding that to our copper solution. No color change occurred, although a precipitate did form. Acknowledging my defeat, I told my daughter I'd bring something back from the lab on Monday.

Today, a few pinches of ammonium carbonate did the trick and restored my standing as a chemist in our home again.
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Instructors at the University of Nottingham have put together a series of short videos describing each element of the periodic table . I haven't had the chance to go through all the elements yet, but it's definitely worth a look.

Chemophilia - Part II

2008-07-18T16:27:00.002-04:00

Continuing in the vein of Wednesday’s chemophilia post, some non-chemists enjoy doing chemical experiments on their own bodies. For example, the LA Times has an article describing the current fad of self-chelation therapies. For those that don’t know, a chelating agent is a molecule that binds to metal ions at multiple sites, generally leading to a very stable metal-chelate complex. Although chelation therapy is performed by doctors intravenously to remove metals from the body in cases of severe metal poisoning, there are various “health” promoters who suggest that ingesting small amounts of these same chelating agents can also remove low levels of toxic metals. There are a variety of reasons why self-chelation is a scam and possible health risk, but that doesn’t stop the websites from selling these concoctions.

A website named "Vibrant Life", for example, describes the benefits of self-chelation. (Sounds pornographic, doesn’t it?). A check of their chelating product ingredient list reveals that it contains a standard mix of vitamins, minerals, amino acids, and 500 milligrams of EDTA as the chelating agent. Considering how poorly EDTA is absorbed through the gastrointestinal tract, you might as well drink Mountain Dew if you want to ingest EDTA. On the other hand, the makers of Chelorex say that oral EDTA chelation is a scam, which is why their self-chelating formula has no EDTA in it. In fact their product doesn’t appear to have much in the way of metal chelators at all – just vitamins, minerals, and amino acids. Hmmm…. Where’s the FDA when you need them?
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Obligatory story from the past about self-chelating… well, sort of, anyway.

A professor back in grad school once told me about a friend of his who was using the old school habit of mouth-pipetting. As you might have guessed, he accidentally swallowed some of the reagent, which turned out to be rather poisonous. (I want to apologize here since I don’t really remember which chemicals were involved, so bear with me.) He immediately began to panic and proceeded to rush from lab to lab yelling for someone to help him. Since no one responded quickly enough for his liking, he ran back to his lab where he had the bright idea of swallowing a second chemical to counteract the first. Again, I don’t remember which chemical it was, but it would have precipitated out the first reagent. Oh, and it was poisonous too. But he drank it anyway.

After calming down a bit, the chemist within began to reassert itself and he wondered if these 2 chemicals would really react at the low pHs present in the stomach. Calmly, he performed the calculations and found that, yes, they would indeed not react under those conditions. So now he had 2 poisons in his system. As far as I know, he ended up suffering no ill effects.

Woo hoo! I made it through an entire post about chemistry and didn't use a single subscript or superscript. Good times, indeed!

Chemophilia

2008-07-16T23:43:00.001-04:00

A couple of weeks ago, I posted about Chemophobia, the irrational fear of chemicals (and possibly chemists too, I suppose). Now I’d like to talk about the opposite extreme, Chemophilia, which I define as a non-chemist’s desire to be a chemist. Let’s face it -- who wouldn’t want to be a chemist? One of the simplest methods for fulfilling those types of dreams is by the practice of chemical collecting. I recently read an article about a doctor in Ohio (recently deceased) who had been collecting chemicals in his garage as a hobby. His daughter was totally unaware of this hobby until she found the chemicals and decided to call the fire department, resulting in significant media attention. Element collecting is not an uncommon hobby, and there are plenty of websites devoted to the practice. Here is one example. (I collect elements myself, but then I’m a chemist.) More surprisingly, there are web sites and organizations devoted to the practice of performing chemistry experiments at home. Not just simple experiments with pretty color changes, but major synthetic procedures. Some of these web sites let you order chemicals and chemical equipment, while some will tell you how to obtain the chemicals on your own. There are discussion groups which give step by step instruction for the synthesis of various compounds – some of them rather hazardous. Sciencemadness is one such site, but there are lots more. Since I’ve been toying with the idea of trying some simple experiments at home, I’m glad there are sources like this available. But it worries me when I think about non-chemists attempting some of the procedures I’ve seen online.

Cell Phone Rant

2008-07-14T23:34:00.004-04:00

Warning: this is a non-chemistry related rant.

Last year, I switched from a monthly cell phone plan (Verizon) to a fixed rate per minute plan (AT&T). My wife had been tracking my cell phone use patterns and had convinced me I would pay less on a pay per minute plan. So far she has been right, although as more and more people at work are beginning to call my cell, that advantage is beginning to disappear. The increase in work related calls is not totally unexpected since I am currently existing in a hybrid state, as I resonate between 3 different locations and the cell is often the easiest way to catch me.

Pay per minute plans tend to make you acutely aware of the length of your calls, especially since AT&T graciously sends you a note after each call telling you how much you just spent. These plans are also the source of much aggravation as you notice all the little things the phone company does to drain your phone card of money as quickly as possible. I don’t mind that AT&T rounds calls up to the next minute, but how do they manage to make sure my calls always last X minutes and 1 second? Slightly more annoying is the phone’s user interface, which is designed to maximize the number of times one can accidentally sign on to the AT&T web store (for which you are charged). And nothing is more annoying than hanging up the phone, seeing the “call ended” message, and then a second or two later seeing a “call resumed” message as the timer begins counting again. WTF? The other party has already hung up. Why is my phone reinitiating the call?

However, these minor annoyances are not why I am writing today. My rant is directed at the callers themselves -- in particular, two people at work that are most responsible for my phone card drainage. It’s not just that they constantly call with no real purpose in mind (Hello! The company does have email, you know?). The real problem is that these two guys simply don’t know how to end a phone conversation. Seriously, phone calls that should barely last a minute drag out for 5 or 6 minutes because they can’t bring themselves to say goodbye.

Cell Phone Drainer (CPD): “Ken, I’ve got those samples you wanted.”
Me: “Great, I’ll come on over to pick them up.”
CPD: (Pause……) “I didn’t have any trouble making them.”
Me: Were you expecting any trouble? You’ve already made dozens of them.”
CPD: (Pause…..) ”No, I just wanted you to know that I didn’t have any trouble.”
Me: OK, I’ll come on over right now.”
CPD: (Long pause……) “Anything happening over in your area?”
Me: “Uhhh, no. Thanks for making the samples. I really need to start working on them.”
CPD: (Pause…..) ” Do you want to come over and get them now?”
Me: “Yes, I’m on my way. Thanks.
CPD: (Long awkward pause….) ”I’ll be at my cubicle.”
Me: “Yes, I know.”
CPD: “Have you been enjoying the weather lately?”

I start watching the timer on my phone.

Me: “It’s been okay. OK, I’m leaving now.”
CPD: (Pause…..) ”The samples should all be fine, I didn’t have any problems.”
Me: (Coworkers in nearby cubicles begin to notice my desperation) “Ummm, I really need to use the bathroom, so I think I have to go now.”
CPD: “You want me to leave the samples at my cubicle?”
Me: “Yes!”
CPD: (Longer pause….) “How do you think the project is going?”
Me: “I think I just heard an explosion coming from the lab. I should really go.”
CPD: (Pause…..) “Do you want a printout for the samples?”
Me: “I’m sure I hear screaming. I should really go now. Talk to you when I get there.”
CPD: “OK….If there’s nothing else…I’ll be at my cubicle….with the samples. You can pick them up anytime. Are you coming over right now?”
Me: “Bye.”
CPD: (Pause….) ”Uhhh… bye…. I’ll… I’ll talk to you later."
I hang up and my cell phone tells me I've been on for 4 minutes and 1 second. Damn!!!

I tend to ignore his phone calls now but then he just leaves messages which require me to call my voice mail (for a fee) to erase. Anyway, thanks for reading. I feel much better now.
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For all those analytical chemists who managed to make it through that rant, here is a link to a music video for those interested in automated pipetting. Woo hoo!!

Disappearing Elements? - Part II

2008-07-09T23:04:00.004-04:00

I’d love to say it’s great to be back home, but I can’t do it with a straight face. Although our vacation only consisted of driving to the other side of the state and staying in Saugatuck (near Lake Michigan) for a few days, it was one of the most relaxing few days I’ve ever spent. Going back to work on Monday was definitely a challenge. Diligent chemist that I am, however, I made sure to practice my chemical techniques throughout the vacation. Examples would include:

1. Oxidizing a fair bit of ethanol with ADH (alcohol dehydrogenase). (Note to self -- consuming ice cream after a bottle of wine is no longer recommended).

2. Altering a large number of my DNA molecules via UV radiation.

3. Witnessing many colorful pyrotechnic explosions. Unfortunately, I’ve noticed that I spend more time trying to guess which elements are being used to generate the colors than I do just ooohing and aaahing like everyone else. At least I’m not trying to make my own fireworks (anymore) like this guy.

So it’s hard enough to get back into the work routine, but now I read over at Practical Transmutations that we may be running out of certain elements. I’ve written about this before, but it seems that the situation is more dire than I originally thought. Apparently, a German chemist has estimated when our supply of certain metals is going to be exhausted. This is not good news for some inorganic chemists. For example, becoming an expert on gallium and indium may not be a good career choice if you plan on working more than 10 years. And as if we aren’t using indium up quickly enough, we now have marketers promoting the use of indium as a promoter of good health. As far as I know, there are no studies demonstrating its efficacy in this area -- only its toxicity. Of course, they used to use arsenic for health reasons too, so who knows?

Anyway, this is not a good way to begin the work week. Stop using up our elements, you swine!

Well Meaning Cheating

2008-07-08T23:08:00.002-04:00

Over at The Chem Blog, there have been a series of posts dealing with cheating in science. As this has been discussed in many forums over the years, I really don’t have much to add other than mentioning that there is one aspect which is rarely discussed – the well-intentioned falsification of your data by someone else. Back in grad school, I was determining a reaction mechanism using labeled ⁹⁵Mo. After conversion of the various Mo products into MoO₄^2-, it was easy to measure the isotopic enrichment using ⁹⁵Mo NMR. To test out the technique, I prepared a sample of ⁹⁵MoO₄^2- and gave it to the NMR guy for analysis. The resulting spectrum was beautiful! A nice symmetrical peak with very little noise. Of course, since I wanted to run a fair number of samples (each sample required 2.5 hours) and since the NMR guy was busy, I soon realized I would have to run them myself if I planned on finishing my degree before my advisor retired. So I learned how to run the instrument and eventually analyzed the sample again for practice. The spectrum looked something like this.
(OK, so I added the boat, but you get the idea. The little stick in the water was the Mo signal)

WTF?! How did I screw this up so badly? I asked other grad students for help. I repeated the analysis with another sample. I tried everything I could think of in my rather limited repertoire of NMR tricks. Nothing I tried made the spectrum look any better. Finally I located the NMR guy who had done the original analysis and asked him what he had done to get such a good spectrum. It took me a little while to figure it out, but I eventually realized that he had prettied up the spectrum a little before giving it to me. Looking back at the original data, his original spectrum had looked a lot like mine, but then he had MANUALLY ZEROED OUT THE ROLLING BASELINE, POINT BY POINT, until I had a nice sharp peak with zero noise. Then he had blown up the spectrum until the small blip looked like a giant Gaussian peak. Needless to say, I never let him run a sample for me again.

Of course, it never occurred to him that he was cheating or manipulating the data. He just figured he was doing me a favor. The moral is: If you depend upon someone else collecting data for you, make sure you always see the raw data.

Vacation!

2008-06-30T22:23:00.002-04:00

I had hoped to put up a new post by Monday, but it was not to be. We will be going out of town for a family vacation for several days, so don't expect to see any new posts until next week. Wish us luck!

Hope everyone gets a chance to see a little pyrotechic chemistry this week.

Chemophobia Part II – MSDS’s

2008-06-27T23:27:00.002-04:00

Note: A three minute storm was sufficient to knock out our power again for about 5 hours on Thursday evening, so this post was somewhat delayed.

Wow! The post on chemophobia evoked more comments than any other topic I've come up with. Must be a lot of pent-up emotion, I guess. During that post I failed to mention an article that covers the subject in much greater depth. The writer jokes that if everyone were required to obtain an MSDS for everything, they’d eventually get over chemophobia. Possibly, but I’d be more concerned that making the general public aware of the existence of MSDS’s might just backfire on us. I mean, has anyone here actually read an MSDS sheet for commonly used lab chemicals? Even the most benign material can sound like a potential terrorist weapon after reading through those things. I once looked up the MSDS for “oil of wintergreen” (ingredient in Icy Hot and mint toothpaste) and capsaicin (active component of chili peppers, also used for muscle pain relief). Despite the fact that these materials are meant to be eaten and/or placed on our skin, their MSDS’s tended to scare me away from their use. ("Sorry, honey, I can't really bring myself to brush my teeth anymore"). Here are a few sentences taken from an MSDS for another common chemical usually found in the lab:

Mutagenic for mammalian somatic cells, bacteria, and yeast.
May cause cancer based on animal data.
May cause adverse reproductive effects and birth defects.
May be toxic to heart, gastrointestinal tract, central nervous system.
Repeated or prolonged exposure can damage target organs.
Hazardous in case of skin contact (irritant), of ingestion, or inhalation.

May cause gastrointestinal (digestive) tract irritation with epigastric pain, abdominal cramps, nausea, vomiting and diarrhea. Affects metabolism and cardiovascular system with symptoms including increase in metabolism, flushing, palpitations, rapid heart rate, dysrhythmias, hypotension, blood pressure elevation and weight loss, metabolic acidosis. May affect brain and behavior/central nervous system.. Symptoms may include nervousness, anxiety, restlessness, insomnia, dizziness, tremor, seizures, convulsions, hallucinations, somnolence, toxic psychosis, tremors, convulsions, ataxia. May also affect blood, respiration (hyperventilation), and urinary system (mild increase in urinary volume and urinary sodium excretion), and may directly produce hypokalemia.

Whoa, that sure sounds like something I should handle with some care! Now I don’t know how many of you actually use 1,3,7-trimethylxanthine in the lab, but I’d suggest being very careful with it. Even non-organikers may have cause for alarm since it is commonly found in aqueous solutions of coffee, tea, Mountain Dew, Coke, and various energy drinks.

So do we really need non-scientists reading these things? I’ve run across plenty of websites where people (obviously not science majors) were misusing MSDS’s to support their argument (e.g., anti-fluoridation groups). The fact that they occasionally used the wrong MSDS's (fluorine instead of fluoride or hexafluorosilicate) did not help their cause, IMO.

By the way, the idea for using caffeine as an example originally came from this website.

Chemophobia

2008-06-25T22:40:00.003-04:00

“So what do you do for a living?” asked the guy standing next to me. “I’m a chemist,” I said, expecting to see his face light up with a mixture of admiration and envy. “Oh…. So you work with chemicals, then?” he said, and his emphasis on the word “chemicals” indicated both repulsion and pity for my unfortunate career choice. I thought about saying, “Everyone works with chemicals, since everything is a chemical,” but I can usually spot a lost cause when I see one so I just nodded and began talking to myself until he decided he wanted to be somewhere else. Why does the term ”chemical” evoke such negative feelings in some people? I suspect that much of the reason has to do with the media (and those who use the media, e.g. politicians). It’s pretty much an unwritten rule in the media that the word “chemical” is only to be used when negative connotations are required. If a chemical is found to be beneficial, words like “substance” or “ingredient” or “compound” or “drug” will be used instead. Here's an article I found discussing the use of chemical alternatives to chlorine in swimming pools. These alternatives include ozone, Cu²⁺, and Ag⁺ to kill bacteria. The pool owners are happy that they no longer have to deal with the problems inherent with chlorine and there’s no problem with that. But you’ll notice that many of these owners (and the writer of the article) indicate they are glad to be in a chemical-free pool. What? Copper and silver aren’t chemicals?

Want to get someone’s attention? Just invoke a chemical name – the longer and the more scientific sounding, the better. There’s been a series of hoaxes over the years based on the supposed necessity of banning DHMO (dihydrogen monoxide). The most recent incarnation occurred last year in New Zealand when an MP was tricked into believing that DHMO might be harmful to the public. DHMO was described to her as colorless, odorless, tasteless, causing the death of uncounted thousands of people every year, and yet so addicting that, for those who become dependent on it, its withdrawal means certain death. Not bad for a substance which covers over two thirds of the planet’s surface.

Weird Water Chemistry

2008-06-23T22:53:00.002-04:00

Recently, Honda announced the Clarity, a fuel cell based vehicle that is advertised as a clean car which only emits H₂O. The fuel, of course, is hydrogen. Now the concept is not new and fuel cell cars have been around for a while, but Honda’s decision to make 200 of them and releasing them to the public is a first step into understanding how well they might work in the real world. There are plenty of obstacles to overcome and so it should be an interesting trial. Of course, there’s a reason (actually quite a lot of them) why hydrogen fuel cell cars haven’t taken off yet, and it has nothing to do with conspiracy theories between the auto and oil companies.

1. Very few hydrogen filling stations
2. No large sources of hydrogen until you reach Jupiter. You either make it from hydrocarbon fuels like natural gas (which negates the zero CO₂ emissions claim) or by electrolysis. And if the electricity isn’t coming from a renewable source, then what exactly are you gaining? (OK, you should still be producing less NOx, CO, and hydrocarbon emissions. That’s a good thing)
3. No one likes the idea of driving around with a 5000 psi hydrogen tank sitting next to them. That is why so many researchers are feverishly looking for materials that can store hydrogen safely at low pressures with good volumetric efficiencies.
4. Price?

However this post is not about cars that produce H₂O emissions, it is about cars that claim to use H₂O as the fuel. The most recent announcement has come from Genepax, which claims to have just such a car. According to Genepax, their car converts water into hydrogen which is then utilized by a fuel cell (along with air) to produce water and electricity. Now think about this. They are taking water, mixing in a little air, and using that to produce water and energy. I would hope that this would set off BS detectors for anyone who is at all familiar with science. Are they converting matter into energy, or what? What is their secret? They pass the water through a special top secret membrane that converts the water into hydrogen. (The reports actually say hydrogen and oxygen, but I doubt they mean oxygen gas as it would just recombine with the hydrogen at the fuel cell electrode with no production of electricity.) Not surprisingly, Genepax is tight-lipped about this membrane, but indications are that it is similar to a metal hydride. Adding water to a metal hydride produces H₂ and a metal oxide. Of course, this means the hydride is the fuel, not the water. Genepax does grudgingly admit that the membrane will have to be periodically replaced (although they do not mention how often that will be needed). Basically it would be like an automaker saying “We have built a car that runs on air only. All you need is a tank full of a liquid hydrocarbon catalyst to make it work.”

The idea of running a car on water instead of a hydrocarbon fuel has been around for a long time, despite the obvious problem with the laws of thermodynamics. But as the price of gasoline has continued to rise, these reports of water-based fuels have dramatically increased. Try googling the term “HHO,” which is the term generally used by the “water-as-fuel” supporters to represent the “improved” form of water. There are several variations on this concept. In one version, HHO is actually supposed to be a high energy form of water, apparently containing H-H bonds. I’m sure the spectroscopists would be very excited to work with this molecule. In the most common variation, however, HHO is a fancy way of saying “a 2:1 molar ratio of H₂ and O₂ gases,” basically the standard product of electrolysis, otherwise known as Brown’s gas. In this incarnation, water is electrolyzed into H₂ and O₂ and this mixture is added to the gasoline/air mix in the engine. The extra energy from H₂ combustion results in better fuel economy. Of course, you have to provide at least as much energy to split the water as you get back, but that doesn’t seem to bother the “scientists” working on these projects. As is typical in these situations, there is just enough truth in there to keep these ideas from dying. Automakers have long known that adding H₂ to an engine allows you to run the engine leaner, which can help gas mileage somewhat in certain circumstances (although your emissions may no longer meet EPA requirements). The best way of producing H2 is not by an electrolysis device in your car, but by reforming a small amount of gasoline to make H₂ and CO. We'll see if the auto companies can get this concept to work.

Garden Complete

2008-06-22T22:15:00.005-04:00

Finally, the gardening project around our house is done. We still have a lot of outdoor (and indoor) projects in the works, but the major project is finished which means I will once again have more time to devote to blogging. In what has developed into a tradition over the years, I signal the end of gardening by posting a sign in the garden.

At this point, everything is on automatic. I've done my part. I've fertilized, mulched, and set up the automatic watering system. Now its up to the plants. It's like setting up a chemical synthesis and letting it reflux for a couple of days while you wait for the product to form. All you can do is wait and hope that the chemicals behave in the manner you believe they should. I'm not going to spend a lot of time weeding. Should a weed manage to thrive, that's not my problem. I've given the flowers a head start. It's up to them. Survival of the fittest, I say. I'll post some pictures in July, when everything starts filling in. Otherwise, back to Chemistry again!

Miscellaneous Thursday

2008-06-19T22:09:00.002-04:00

This will be one of those miscellaneous, rambling posts I write when I’m too lazy to actually put any critical thought into a subject.

First Item: Looks like I’ll have about 5 minutes less a day to accomplish anything at work since the spam filter on our firewall has apparently died a horrible death. I used to get about one email a day suggesting that I buy certain stocks, but that was about it. Since Monday morning, I’ve suddenly been averaging about 10 spams a day. I’m not sure if my name suddenly appeared on a list somewhere, but I’ve been deluged with offers from:

eHarmony and various other dating services. Hmmm... why?
Help in obtaining credit cards.
Debt relief services – for when I max out those credit cards.
Unbelievably cheap insurance.

I’ve generally been immune to spam both at work and at home, which is a surprise considering all the web sites I visit. I have a coworker, however, who used to regularly receive several Viagra-type emails a day at work. Not sure what sites he was visiting.

Second Item: New Scientists has a video of robots whose forms were inspired by animals. It’s not chemistry related at all, but my daughter, who is into both animals and building robots, thought it was great.

Third Item: Over at Practical Transmutations, there is a picture of a T-shirt with the “original” periodic table printed on it. Very cool! Perhaps we also need an alchemical periodic table with only the original seven elements.

Finally, we have the top ten list of scientists killed or maimed by their experiments. Really makes you want to run into the lab and try that crazy experiment you dreamed up last weekend over that pitcher of beer. Reminds me of how naïve I was about the dangers in the lab back when I was an undergrad. Good thing my mom never knew about these things or she never would have let me get into science in the first place. She certainly wouldn’t have left me alone with my first chemistry set.

P.S. I don’t remember how I found this link, so apologies to whomever I might have slighted by not mentioning them.

Poisons of the Day - Part Ia

2008-06-18T22:27:00.004-04:00

News Flash! Napoleon probably did not die of arsenic poisoning. I would like to say that I’m surprised by this, but I can’t since I had never heard of the “Napoleon was poisoned by arsenic” theory in the first place. Apparently, arsenic had previously been found in a sample of Napoleon’s hair, and when combined with reports of his severe stomach pain (a symptom of arsenic poisoning), it had been speculated that Napoleon was either poisoned by the British during his captivity or had been exposed to poisonous arsenic fumes generated by mold infested wallpaper containing an arsenic-based dye. But a team of Italian scientists has now cast considerable doubt on this theory. By collecting samples of Napoleon’s hair at various stages of his life, along with hair from his son and first wife, they were able to show that all three of them had had elevated levels of arsenic in their bodies long before Napoleon’s imprisonment.

What made the story interesting was that the levels of arsenic in Napoleon’s hair were 100 times greater than expected today. Apparently, back in the day, consuming small amounts of arsenic was a highly regarded practice. It was supposed to make the body more vigorous, it was believed to be a sexual stimulant, and its tendency to produce bright, rosy cheeks was much in demand by the women of the time. (The rosy cheeks were a result of blood vessel damage in the skin.) The knowledge that arsenic was a poison, and that it caused severe stomach pain, was apparently not much of a deterrent. (To make things worse, facial powders were often loaded with white lead, Pb3(CO3)2(OH)2, in order to make the face more pale -- a sign of nobility.)

Now the reason I mention this story relates to the “Poisons of the Day” post from last week in which I mentioned that much of arsenic’s toxicity arises from its tendency to replace phosphorus in the body. My question was: How could people continue to survive the continuous ingestion of arsenic if it’s slowly replacing the body’s phosphorus? In fact, anecdotal reports suggest that it is possible to build up some immunity to arsenic by regularly ingesting it -- although some experts reject that possibility. Now, I know that you can build up an immunity to the poison "iocane" (warning: Princess Bride reference ;) ), but how would that work with arsenic? One theory involves metallothioneins, which are proteins produced by the body that seem to bond to ions of dangerous elements like arsenic and cadmium and help minimize their effects. Constant exposure to arsenic might increase the levels of metallothioneins produced by the body. I don’t think anyone knows the answer just yet.

By the way, I found a few references to a second mechanism by which arsenic can be toxic. It tends to bind to the sulfhydryl (thiol) groups (-SH) in proteins, which as you can imagine, really screws up the operation of these proteins.

The Power Returnth!

2008-06-16T23:18:00.001-04:00

Finally! As of 7:20pm, on Saturday the 14th, electrons are once again running through every corner of our house. Not the artificial kind created by our generator, but honest to goodness real electrons, captured in the wild by Detroit Energy (DTE) and sent to our house. I would like to thank DTE for getting us back online, but I will temper my thanks with the following two caveats. First, I realize that we were placed at the end of the queue due to the complexity of the repair job and the fact that only 25 houses were affected in our area, but I did not appreciate being pushed back in the queue in order to work on houses which lost their power two days later during a second storm. Let them wait their turn. Second, when the repair crew did finally show up, we were not at all impressed by the arrival of six trucks when only two were needed. Watching 10 DTE guys sitting around doing nothing for 3-4 hours while the 2 tree guys cut down a branch (eventually one of the DTE guys did spend about 10 minutes fixing the line itself) pretty much explained why it had taken DTE 6 days to fix our area. Hint: actually keep track of your crews and explain to them that it is possible to work on different jobs simultaneously. Audiences are not required.

Here is an accounting of our costs associated with the power outage:
Item: Several gallons of lemonade consumed. Cost: $10
Item: Eating out at restaurants. Cost: $47
Item: 36 gallons of gasoline for generator. Cost: $148
Item: Hearing the power come back on, turning on the air conditioning to its lowest possible temperature, sitting back, and watching icicles form on the window. Cost: Priceless.

In more important news, Venezuelan researchers have identified another chemical pathway which causes beer to lose some of it flavor during storage. They have even managed to inhibit this reaction (which generates phenylacetaldehyde, by the way) by blocking the pathway with diaminobenzene. Unfortunately, diaminobenzene is toxic, so the current solution would probably not be considered optimal. After all, if beer drinkers start keeling over, then it’s just going to take longer to go through the world’s supply of beer and thus lead to longer beer storage times and additional flavor loss. Fortunately, they are continuing to work on the problem.

Still Without Power, But Blogging Anyway!

2008-06-13T23:15:00.003-04:00

What can I say? Life without electricity is teh suck. We've been without power for 5 days now and DTE (Detroit Energy) still has no idea when they will be getting around to our block. I suppose I shouldn't complain too much since we have a gas powered generator, but I'm getting tired buying 5-7 gallons of gas everyday to keep it running. About every 6 hours I have to shut down the computer, disconnect the generator from our circuits, shut down the generator, refill the gas tank, start it back up, reconnect it to our circuits, unplug/replug the router (since the cable modem box most likely has a new IP address), restart the computer, and start the 6 hour timer. Amazingly, the novelty has disappeared -- just like my patience. Fortunately, after the first 2 days, the temperatures have dropped to the point where it's comfortable in the evening.

Both of the kids had their last half-day of school today and we celebrated by ~~buying gasoline~~ going to see the new Indiana Jones movie. I won't bother reviewing it in any detail, but it was your classic over-the-top escapist movie. It kept us entertained and the theatre was air conditioned, so it was a success by any definition.

After much procrastination, I've finally started adding links to other chemistry blogs I read on a regular basis. You probably already know about most of them, but I've been remiss in not listing them before. Happy Friday!

Poisons of the Day - Part I

2008-06-12T23:42:00.003-04:00

I’ve decided to start a little series called “Poisons of the Day.” This series is not to discuss the use of poisons to remove irritating coworkers in the chemical laboratory, but to understand why many elements and simple compounds are poisonous, something I’ve never really thought about before. Ever since I ran into an article describing the mechanism of arsenic poisoning, I’ve been interested in the subject. After doing some research I have come to the conclusion that there appears to be four main ways in which an element can be poisonous.

1. It binds to and/or removes necessary elements or compounds from the body
2. It replaces an element already in the body, but cannot fulfill the same role.
3. It’s a necessary element for life in small amounts but causes trouble when too much is around.
4. It interferes with the chemical reactions in the body.

I’ll start out with four poisons today.

ARSENIC
This is the element which got me started on this series. Arsenic does not attack the body directly, it operates by replacing the phosphorus in the body. Since it sits just below P in the periodic table, it tends to bind to the same compounds that phosphorus does. As you might expect, the arsenic analogues do not work very well, if at all. ATP, the molecule responsible for storing and releasing energy, is particularly susceptible to arsenic poisoning. In the presence of arsenic, cells tend to die from energy starvation.

LEAD
Lead is another poison which works by slowly replacing other metals used by the body, in particular, calcium, iron, and zinc which are cofactors in many enzymatic reactions. Lead tends to bind to the same enzymes as these metals, but the resulting molecules fail to function properly, usually because the shape of the protein is no longer correct. It is known to interfere both with the production of heme (Zn replacement), which leads to anemia, as well as the transmission of electrical impulses in the brain (Ca replacement) which impairs brain function.

BARIUM
Barium apparently causes problems in a lot of ways, but its primary role occurs because it interferes with the sodium-potassium pump used by our muscles. Apparently it reduces the permeability of muscles to potassium entry. This can lead to paralysis, and if the affected muscles include the heart and respiratory muscles, death. Barium does also appear to replace calcium in the body, but this is a minor effect.

I hadn’t really appreciated how toxic barium is, assuming that it’s in the form of a soluble salt. Barium carbonate is a common rat poison. Barium sulfate is so insoluble that you can drink it with no ill effects.

D₂O
I include this compound because I used D₂O (deuterated or heavy water) back as an undergraduate for isotope labeling experiments. My undergraduate advisor used to tell me that if you drank enough of it, it would kill you. Apparently he was correct, although you would have to work really hard to get your body deuterated enough to have an effect. If you can replace between 25 and 50% of the water in your body with D₂O, then you’ll notice the health effects, but this will require the drinking of nothing but large quantities of D₂O for at least a week according to Wikipedia. The poisoning mechanism is pretty simple. Deuterium has slightly different hydrogen bonding properties than hydrogen (which is why we use D₂O in the lab in the first place). Our bodies consist of large number of proteins, including DNA, which depend upon hydrogen bonding to hold them in the rather complicated conformations which are necessary for certain enzymatic reactions to occur. Start changing the hydrogen bonding in our bodies and you can imagine what kind of problems would result.

I’ll have more poisons to discuss at a later date.

When the Elements are Against You

2008-06-11T21:55:00.000-04:00

The elements are conspiring against me. I’m finally ready to start posting again and then we lose power here on Sunday due to the storms that swept through the Midwest. It’s been a little hectic around here to say the least, and at the present time, DTE is not expecting our power to come back until late Thursday. Fortunately, we have a gasoline powered generator and so we have enough power to run the important things: TV, computer, internet, fans and…, oh yeah, the refrigerator, microwave, and freezer.

It’s my six year old son who is having the roughest time. He experienced his first blackout this winter, when we lost power while I was giving him a shower. Without warning, the bathroom went pitch black and he started panicking. I was reluctant to leave him to go open the door because he was covered in soap and I was afraid he was going to slip and fall during his panic attack. Eventually I got him out of there, but afterwards he started using the term “power outage” several times a day for several weeks. After Sunday, he’s added “thunderstorms” to his daily vocabulary. He’s even learned how to bring up a local area weather radar map on the computer, which he now does constantly to check for any indication of an impending storm, despite our assurances that nothing is imminent. (He’s apparently already reached the age where he believes what he sees on the Internet more than what his parents tell him.) Even a partially overcast sky now starts to worry him, which makes me feel a little guilty since I actually enjoy rainy days and thunderstorms as opposed to hot summer days (northern European ancestry, no doubt). My wife, whose ancestry is Maltese, thinks I’m crazy. Who’s to say she isn’t right?

Better Living Through Chemistry

2008-06-06T10:58:00.003-04:00

Wouldn't you just know it. I'm finally back to blogging on a regular schedule and then I come down with a severe head cold. I'm getting better, but I just came into work long enough to move my boxes from my temporary cubicle to my new permanent desk. And I'm now exhausted. As soon as the customer meeting is finished, I'm outta here.

Here's a note I received from a coworker who is lucky enough to have a pool.

"Still not feeling well? Maybe, you can sweat it out this weekend. Opened the pool yesterday to see the Black Lagoon. Already put 8 gallons of Chorine in. Hit it with every chemical known to man. Still going to take a couple of days before I risk catching the plague."

It makes me proud that chemistry is such a boon to mankind. Sniff...Sniff.. Sorry, I've got to go now, there's something in my eye. Yeah, that's it...

Garden Chemistry

2008-06-03T22:58:00.006-04:00

Considering all the time I’ve spent gardening, it’s amazing how little I’ve thought about all the chemistry that surrounds me in the garden. Of course I realize there is a lot of organic and bioinorganic chemistry going on in the plants, but there is actually a fair amount of inorganic chemistry occurring in the soil itself. Almost 99% of a typical fertilizer consists of nitrogen, phosphorus, and potassium, but in order to survive, however, plants also need small amounts of magnesium, iron, calcium, boron, sulfur, copper, zinc, and manganese. Although these elements are usually present in the soil, their bioavailability isn’t always guaranteed. Most plants perform best in a pH range of 6-7.5 and much of this has to do with the availability of these trace elements as shown on the following chart obtained from this website.

Much of this availability has to do with the form of the element. To be useful to the plant, the elements generally have to be in an ionic form, which is why some fertilizers chelate their metals. Nice healthy soils with lots of organic matter or clay essentially behave like ion exchange resins, holding on to and stabilizing the ionic species for eventual use by the plant. If the pH is too high, insoluble metal oxides (Cu, Fe, Mn) can form. If it’s too low, too much Al³⁺ is released from rocks, which displaces all the other elements on the ion exchange sites.

Redox properties can also have an effect. Well aerated and well drained soils tend to be oxidizing while wet, decomposing, clay soils tend to be reducing. In the presence of sulfur, anaerobic conditions lead to formation of insoluble metal sulfides. Anaerobic conditions also increase Fe availability by changing its oxidation state from Fe³⁺ to Fe²⁺ (which I assume makes it easier for its release from the ion absorption sites. There is a lot of complicated chemistry going on here.

I admit that I was totally unaware of any of this when I started gardening. In fact, the only reason I even know this much is due to having to understanding how to change soil pH. Lime is used to raise soil pH while iron salts and elemental sulfur are used to lower soil pH. The lime and iron reactions I understood from freshman chemistry, but sulfur? Gardeners would simply tell me that sulfur is acidic, but that obviously wasn't true. Eventually I guessed (correctly) that the sulfur oxidizes to SO₂ which dissolves in water to make H₂SO₃.

What do I do with all this knowledge? Well, nothing really. I just plant the flowers, add Miracle-Gro, and hope everything grows.

Okay, So It's Been a Week and a Half Since I Last Posted

2008-05-29T21:51:00.004-04:00

Okay, okay.... So it's been a week and a half since I suggested that my frequency of posting was going to return to normal. I've been so busy at work trying to solve another problem (which recently came to our attention) that I haven't even been keeping up with other chemistry blogs, which are often my inspiration for posts. I'm still getting up at 5 in the morning in order to work in the garden (it's the only time my wife allows me to do whatever I want), so I don't feel like staying up very late writing these things. And the Pistons are still in the playoffs, although that could end at any moment. Since I don't have anything new to post today, I'll just try to amuse you with my best sodium explosion story from grad school.

It was an organic analysis lab class and we were heating some unknown organic material with sodium for some reason. Organikers may remember why. Perhaps we were trying to convert NO2 groups to NH2, I'm too tired to look it up. Well, somebody failed to decompose the leftover sodium pellet in their testtube with ethanol, and so when they threw the products into the sink, the sodium exploded after sitting a few seconds in the bottom of the drain pipe. No big deal, really. We'd all heard explosions before, but when the TA walked back into the lab (he had been gone during the explosion), he started sniffing the air and asked if anything was burning. We could all smell the sodium in the air. We dutifully denied any knowledge of this and he let the matter drop. What made the incident memorable to me was that the bunsen burners throughout the lab were all bright yellow, a clear sign of the sodium in the air. In fact, the relative brightness of each burner throughout the room clearly identified which sink had been the site of the explosion. The TA never noticed.

It's Over!

2008-05-19T21:41:00.002-04:00

No, not the blog. But the customer presentation which we've been spending all our time (including weekends) preparing. We gave the presentation today and it went well, including the chemistry part which required us to squeeze all the chemistry onto 5 slides. Needless to say, that was not easy at all. Anyway, I should now have time to start blogging again. I still have much to do in the garden, but until the weather starts warming up a little more, I'm afraid to actually plant anything since a sudden frost can still wipe everything out.

So start expecting this blog to come alive again!