Not Really a Molecule
moleculeoftheday | April 22, 2009Going through emails, I came across a request from ASPEX to link to a scholarship they're offering. $1,000 and "an opportunity to co-author a poster with ASPEX at Pittcon 2010." If you are an undergrad thinking of applying for this, going to Pittcon might be worth more than the $1,000. You couldn't ask for a better analytical chemistry meeting to attend, and this could be a great place to find a job or grad school advisor.
Also, if you have something you'd like to see SEM'd, they'll do it for free (although you have to be OK having it out there for the world to see).
moleculeoftheday | November 26, 2008The Royal Society of Chemistry is offering a million pounds to anyone who can bring them 100% chemical-free material.
The manufacturers of a popular "organic" fertiliser recently drew the attention of the public when it claimed in promotional materials the product contained no chemicals whatsoever.
The product's manufacturer makes the fantastic claim to be "100% chemical free" in its advertising and on its packaging. The back of the packaging lists its chemical-free ingredients, which include phosphorus pentoxide and potassium oxide.
moleculeoftheday | September 12, 2008I've been following this hurricane season unusually closely, because I know more people in affected regions than ever. My favorite place to stay caught up is Jeff Masters' blog. You can find lists of survivors and donate to hurricane relief at the Red Cross.
moleculeoftheday | August 5, 2008If you have been reading SB long enough to remember the DonorsChoose promotion, you might be interested in this. It's videos of scientists talking about their first experiments and why they like science, and if you vote on the one you like best, DC gets a buck. Check it out here.
moleculeoftheday | June 1, 2008Even in the case of floating severed feet, apparently!
Ebbesmeyer said it may not be a coincidence they were found in the same area. He said left shoes and right shoes often tend to wash up at different times at different places because they float differently.
He added that there are beaches that collect mostly rights and others that collect mostly lefts because the winds or currents sort out left and right foot wear.
moleculeoftheday | May 31, 2008I've been thinking more about energy sources since oil was at $50/barrel . Since we reached the staggering heights of the last few months, I've been puzzling even more over what people will move to next.
Key to understanding this stuff is how much energy it takes to get your source in a useful form. A paper from the 1980's is illustrative: oil cost more than 10 times less energy to get from discovery to usable energy in the 40's than in the 70's. A lot of technologies barely broke even. If anyone has a newer version of this work, I'm interested.
For better or worse, I think you're going to…
moleculeoftheday | April 18, 2008A couple previous molecules of the day were in the news today: polylactide and lead chromate.
I previously covered the use of polylactide in plastic bottles. I also covered a big downside - it's not the sturdiest stuff. Today, Popular Science has a story about its use in plastic bags, which isn't that bad an idea strength-wise, but it is a bit of a bad idea in the sense that we need to wake up to the fact that we are running up against a wall in our ability to ability to produce enough corn to produce oil, staggering though our ability to produce it is.
Also, lead chromate, which apparently…
moleculeoftheday | March 27, 2008Certain compounds occur as "hydrates"; that is, with one or more molecules of water. Sometimes there is just water trapped in the crystal structure at a specific stoichiometry (i.e., creatine), sometimes the water is actually covalently incorporated into the molecule, as in formaldehyde hydrate.
Sodium acetate trihydrate is the first case - just crystals of sodium acetate + 3 molecules of water. If you heat this up, it "melts," but it's arguably not "molten," you're just dissolving the NaOAc in the water and making a ~10M solution - well above the saturation limit, but it'll stay in solution…
moleculeoftheday | March 17, 2008I posted Sunday and last year about the putative use of fluoresciein in the Chicago river on St. Patrick's day. As some readers pointed out, they apparently aren't using it anymore.
I don't even have a guess what they're using, then. The reason the solid dye is orange is because it absorbs blue-green light, and the reason the river looks green is because it fluoresces, emitting green-green light.
Whatever they're dumping in the river has about that absorption spectrum and about that emission spectrum, and it's got to have a very high emission quantum yield (that is, it has to convert…
moleculeoftheday | March 14, 2008Wow, sorry. I pretty much missed a whole week there. A consolation Friday entry coming up, but first, if you enjoyed Breaking Bad, you might enjoy Trampled Underfoot, the autobiographical blog of Todd Hall, a chef in the Southwestern US. His career oscillated for years between some dizzying successes and crippling substance abuse problems.
He was a rising star in Phoenix for awhile, even won a James Beard award, and was repeatedly profiled in the local indie rag. He ended up in jail in California for awhile for bad checks, and out of this came perhaps the funniest story about him.
He offered…
moleculeoftheday | February 1, 2008125 years ago, a physiologist named Sidney Ringer discovered that a solution of saline prepared by his assistant seemed to keep excised rat hearts beating longer than normal saline.
It turns out this is because the assistant was a lazy slob and used London tap water instead of distilled. Good thing, too - the water, being hard, had a substantial amount of Ca2+, which we now appreciate is important in muscle function.
A derivative of the solution (invented only 50 years later) still lives on, Ringer's Lactate.
moleculeoftheday | October 1, 2007Tin is a nice enough metal, strong and nontoxic enough that for some time we made food-grade cans and foil using it in part. It has a darker side, however: tin pest.
Below a relatively high temperature (ca 13C/55F), "white tin" can convert to a different, more brittle phase, "grey tin." This is called tin pest. Tin, stored cold, will crumble.
Cruelly, such processes are autocatalytic and are difficult to stop once they start (save storing your tin at more friendly temperatures). As the wikipedia article notes, tin pest killed North Pole explorers, Napoleon's men, and destroyed church organs.…
moleculeoftheday | July 13, 2007My Science Project Answers Your Questions. Pretty terrific.
Back Monday.
moleculeoftheday | June 15, 2007Internets troubles. Not sure when this will be fixed, but expect posts to be irregular to absent until at least early-mid next week...
moleculeoftheday | June 6, 2007Periodically, we get these "Ask a Scienceblogger" questions via email asking for someone to volunteer to answer. Usually I don't feel like I have anything to add, but this one was frivolous enough for me to know something about it... Sorry for the not-a-molecule post, back with the regular content tomorrow.
A square piece of dry paper can not be folded in half more than 7 times. Why?
Actually, it's a myth:
Once, in undergrad, an acquaintance offered up a bet for $100 to anyone who could fold a piece of paper nine times (or some other number greater than conventional myth - eight, maybe).…
moleculeoftheday | May 10, 2007Galinstan is an alloy of gallium, indium, and tin (the Latin is stannum). It's (relatively) nontoxic and liquid at room temperature. For this reason, it's used as a mercury replacement in some applications (you can find galinstan thermometers, for example).
Unfortunately, galinstan isn't quite as cool as mercury - mercury tends to bead, while galinstan "wets" things (coats them). This makes it a mess to handle and not useful to many of the applications mercury is best at.