"The chymists are a strange class of mortals, impelled by an almost insane impulse to seek their pleasure among smoke and vapour, soot and flame, poisons and poverty; yet among all these evils I seem to live so sweetly that may I die if I would change places with the Persian King."
Johann Joachim Becher (phlogistonist)
Acta Laboratorii Chymica Monacensis, seu Physica Subterranea, (1669).
Tuesday, September 23, 2008
Tuesday, September 16, 2008
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. 
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.
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.
 I never know whether I should use a hyphen after the term "nano," so I tend to be rather random with its use.
Monday, September 15, 2008
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. :)
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.
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
Tuesday, September 9, 2008
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.
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!
Monday, September 8, 2008
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 400oC) 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.
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
Sunday, September 7, 2008
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.
Friday, September 5, 2008
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.
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?
Wednesday, September 3, 2008
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.
Tuesday, September 2, 2008
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.
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).
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.