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.
Monday, October 26, 2009
Tuesday, October 6, 2009
Bacteria - The New Chemists
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.
----------------------------------------------
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.
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.
----------------------------------------------
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.
Friday, September 18, 2009
Modern Chemistry (Sets)
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?
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?
Wednesday, September 2, 2009
New World Order?
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.
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.
Friday, August 28, 2009
Post-Doc Stories
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.
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.
Tuesday, August 11, 2009
Back on the Air Again
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?
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?
Saturday, July 11, 2009
A Real Sabbatical
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.
Note: It's apparently much easier to post when the weather is less than ideal.
Thursday, June 11, 2009
Are You Ready for the Digital Transition?
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.
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?
Just great. They’ve officially decided to add element 112 to the periodic table. Like I really needed another name to memorize.
Thursday, June 4, 2009
A Babelfish for Chemists
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
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
Tuesday, June 2, 2009
Arsenic (Again) and Drugs
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.
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.
Friday, May 29, 2009
Mediterranean Cyclones
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.
-------------------------------------------------------------
Two new elemental podcast are now available at Chemistry World. This week's elements are zinc and radon.
Thursday, May 28, 2009
Poisons of the Day - Part Ib
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.
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.
Friday, May 22, 2009
The End of the Hydrogen Economy?
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.
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.
Thursday, May 21, 2009
The Science News Cycle
PhD Comics has some interesting comics relating to science and the news. Here's one example:
Go check out the site.
Monday, May 18, 2009
Francium -- Probably Only Good For About One and a Third PhDs
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.
* Post title was edited based on Mitch's comment.
Thursday, May 14, 2009
A Fear of Drugs
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.
-------------------------------------------------
1Some alcohol was consumed during the talk, so take these numbers with a grain of salt -- the inorganic kind.
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.
-------------------------------------------------
1Some alcohol was consumed during the talk, so take these numbers with a grain of salt -- the inorganic kind.
Wednesday, May 13, 2009
Bioelectricity
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.
Of course, this only helps lower our dependence on oil if we’re all using electric cars.
Monday, May 11, 2009
Bad Science -- Toxic Salt
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.
“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.
Wednesday, May 6, 2009
Ruthenium Compound Splits Water
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.
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.
Subscribe to:
Posts (Atom)
