ACS Day 2: March 22nd

An interesting day at the 239th ACS National Meeting and Exposition in San Francisco: The most popular booth at the expo, Open Access publishers, and Going meatless NOT the way to save the planet.

Aside from talks and meetings, the huge vendor exposition also takes place through Wednesday in Moscone South’s large Halls B&C.

As you can see, hundreds of vendors and many more hundreds of attendees showed up. An interesting and, after a quick headcount and comparison, the most popular booth at the Expo was Rod Griffin’s Australian Boulder Opal…jewelry display:

It just goes to show…even chemists can’t resist shiny things.

Also showing up were a few Open Access journals, such as Chemistry Central. These are free, online, peer-reviewed publications. A while back I wrote a pro vs. con on open-access journals here. Feel free to check it out and let me know what you think. Some “selling” points of Chemistry Central are:

• free online access
• peer review
• authors retain copyright to their work
• rapid publication

On the science side, an interesting report presented at the meeting concluded that decreasing the consumption of meat and dairy products won’t have a major effect in combating global warming. Unfortunately the misconception that the world “going meatless” will significantly reduce greenhouse gas production is becoming more popular. Initiatives like “Meatless Monday“, while we can respect their goal of improving our personal health, incorrectly believes that cutting back meat consumption will “improve the health of our planet”. There is even a European campaign called “Less Meat = Less Heat” that was launched late last year (although TreeHugger thought of that catch phrase first).

Now people who have read the 2006 UN report on climate change, which claimed that the livestock sector is responsible for more greenhouse gas emissions (measured in CO2 equivalents) than the transportation sector, will call foul on Frank Mitloehner, Ph. D. UC Davis; the air quality expert that presented the scientific rebuttal on Monday. He faulted the methodology of the UN report and contended that the numbers for the livestock sector were calculated differently from transportation. The calculated livestock emissions included gases produced by growing animal feed, animals’ digestive emissions, and processing meat and milk into foods. The transportation analysis factored in only emissions from fossil fuels burned while driving and not all other transport life-cycle related factors. [ACS Press Release March 22, 12p.m.]

Mitloehner says that instead of focusing our efforts on cutting back meat consumption, developed countries should focus on increasing efficient meat production in developing countries where growing populations need more nutritious food and archaic farming practices produce more greenhouse gases.

There were a couple of other things. Cold Fusion quacks were out in force with their new book. Also, the Sci Mix was a blast, even if I didn’t get any drink tickets (and unlike Mitch, didn’t go begging). I found a lovely example of recycling in chemistry that I’ll blog about later.

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Online Textbooks: ChemWiki Part 1

I remember buying my first O-chem books back when I was attending DVC (Diablo Valley College), a not-so-little community college here in the Bay Area. At first I checked the bookstore and lost my lunch when I saw the price of the new books. The text was $215, the lab manual was another $70, and the solutions manual was $100. Unfortunately, a new edition had been released that year, so even though the professor said that we could use older editions, many of the problem sets wouldn’t match up, so we’d have to get the problems from our classmates. In the end, the cheapest and most convenient route was to go online and buy the international editions. Even after extending the method to all my other classes, I still paid almost $500 for books that semester. Now I attended DVC before California went belly-up, so my classes were still a great bargain at $18 a unit. Since I usually took ~19 units, my total tuition cost was around $350 a semester. The cost of the books were actually greater than my cost of tuition. The sad thing is, this wasn’t an unusual case. Luckily this wasn’t too much of a hardship for me; I had a job on campus and money saved up. However, I knew a lot of students for whom the beginning of the semester meant not eating lunch in order to save up gas money.

Now students have probably been complaining about textbooks since time immemorial. Aristotle probably complained that his scribe made spelling mistakes in his copy of The Republic. Most of the time our bellyaching is justified. Not only do textbooks cost a lot, but there is often a gross amount of errors in them. Everyone knows that the first time you find a caption or answer wrong, it makes the rest of the book suspect. Also, these errors give the publishers a reason to release a next edition…that never seems to fix even half of the errors. However, they do switch around problem numbers, add a few pages of new content, and possibly even rearrange chapters. So now the professors lesson and homework plan, that goes by chapter numbers, page numbers, and problem numbers, is moot. And the student is effectively forced to buy the new edition (price “adjusted for inflation”) or suffer some inconveniences. Most choose to simply buy the new edition since tracking down the old one can be difficult and you have to be quick. Also, sometimes bookstores won’t buy back the old edition so if you had it, and an edition switch occurred before you finished your course track, you are up the creek.

Some of these issues can be addressed with online textbooks. The idea of supplementing physical texts with online modules has been around and implemented by publishers for many years. However, I’ve yet to see a good entirely online chemistry textbook. The advantages of online texts are of many: accessible anywhere you get 3G or Wi-Fi and have your mobile device, interactive learning capabilities, easy distribution, instant update/revision, and low cost publishing (server fees). Of course this won’t necessarily result the publisher make more money, but at 4 billion (yea, you read that correctly, billion) dollars a year, the industry doesn’t really need much help.

The student, however, does. We need these online textbooks, not just to save our wallet, but also to help prevent being stuck with an expensive and lousy text for a year that does a poor job of explaining the material. That expensive O-Chem book I bought really was terrible and it forced my professor to do a lot of extra work in teaching us not to follow the book’s direction of simply memorizing 500 reactions, but to see the patterns and the underlying physical explanations. In the end, we learned from his powerpoints and I paid $215 for a glorified reference book.

Well, some people are pioneering an effort to create an “Open Access Textbook”. In a perfect example of “chem 2.0″, UC Davis Professor Delmar Larsen is the project director of the ChemWiki, a truly free online textbook written by everyone, for everyone. In an absolutely Herculean effort, the developers and Larsen (Mary Obrien, Ron Rusay, Brent Krueger, Michelle McCombs) are trying to create a free and complete, as in covering all branches, chemistry textbook using a community of students, faculty, and outside experts from around the world. Of course they aren’t there yet, and there is still a long way to go but hey, their text literally gets better everyday.

Now I know you probably have a lot of questions: what about correctness and plagiarism? Could such a thing ever be considered an Authority? What do the publishers say? Does anyone actually use the thing? Well, it just so happened that a couple of weeks ago, I was at Davis for the Borge fellowship visitation and I had a chance to talk with professor Larsen who agreed to answer some of these questions for me. In a couple of days, I’ll post the interview here. For now, I suggest you go and check out http://chemwiki.ucdavis.edu/ and browse not just through the core, but the wikitexts and community as well.

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Silly Find from the Internets

Not much today. I saw this earlier and remembered having one of these moments back in G-chem that made me want to break the stupid buret. Actually, that happened on the last day of the semester, during checkout, after I washed it and was walking to the stockroom to return it. I forgot how long the damn thing was, and as I was walked out of the lab the door closed on it, cleaving it in two.

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Antimatter generator…in the clouds?

Antimatter detected using a track etch detector.

In a very surprising series of measurements made by the Fermi Gamma-ray Space Telescope, gamma events matching the signature of energetic positron decay were found just before, during, and after a pair of lightning storms.

For those not familiar, the Fermi telescope allows astronomers to study black holes, pulsars, the subatomic particles emitted by them, and very, very high energy particles far beyond what we are currently capable of producing on earth. Also, positrons are anti-electrons, a form of antimatter. They are also known as the emitted particle from Beta “+” decay, where a proton is hit by the magic wand force, and turned into a neutron, positron, and neutrino.

Now antimatter has never been seen in lightning storms before, although I do wonder how hard they looked. I mean, watch even just a normal patch of sky for long enough (although I really mean loooooonnnggg), and you’ll see lower energy gamma flashes from annihilation of positrons emitted from Oxygen-15, Nitrogen-13, Carbon-11, and maybe a couple of others. However, what the Fermi scope saw is interesting because the energetic decays imply that the electric field associated with the storm switched directions for some reason. See, normally they see gamma rays from decelerating electrons moving toward the detector, (Bremsstrahlung Radiation) however this time they saw radiation from the positrons. Now since positrons have the opposite charge of an electron, they move in the opposite direction in a given electric field orientation. So where electrons were braking, positrons would have been accelerating. Since they saw positron braking radiation, the orientation of the field must have been flipped from usual. Pretty nifty.

Why is this happening? Well, obviously it has something to do with 2012. Damn those Mayans…they’re always right.

Link to Science News article: http://www.sciencenews.org/view/generic/id/49288/title/Signature_of_antimatter_detected_in_lightning

*EDIT: that was fast. Someone asked what the picture in the top left was. Looking from bottom up: A photon (unseen line starting from around the yellow dot to the branching point above it) colliding with a particle generating matter and antimatter particles which fly off into two spirals. The much less energetic photon is later converted to an electron and positron visible as two diverging tracks later on. The extra track I didn’t talk about, which runs up and off to the right, is from the particle that collided with the first photon. So in sum, you are looking at the birth of matter from energy.

*EDIT 2: The above picture is from Stephen Hawking’s Universe Episode 3, Cosmic Alchemy. You can watch the part here. Pretty pictures start around minute 3:20.

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Maz Goes Politician

Ever since the budget crisis began here in California, Mitch and I have debated how we would fix the problem if we were in positions of power. While we had some pretty great, and pretty terrible ideas, we soon stopped wondering what we would do in hypothetical situations and began to wonder how we could actually make a difference. Well, we decided to begin stepping into the world of politics; hoping to influence policy decisions that affect scientists and chemists for a start.

Enter ACR 88, a bill introduced by assembly members Torlakson (D-Martinez) and Furutani (D-Carson) in California.

The bill creates the California Task Force on Science, Technology, Engineering, and Mathematics Education (Task Force) to promote the improvement of science, technology, engineering, and mathematics (STEM) education across the state. The task force would generate discussion on policy that would improve the teaching of those subject areas for California’s K-12 students. It has no fiscal impact (the task force members are not paid).

You see, currently a full third of the 4th graders and a fifth of the 8th graders in the nation can’t preform basic computational math, and US high school seniors recently tested below the international average (out of 21 countries) in math and science.

Out of this poor group, take the fact that California ranked 46th (against other states) in math proficiency and 42nd in science proficiency on recent 8th grade National Assessment of Educational Progress (NAEP) tests.

And it still gets better. More than 50 percent of California 4th and 8th grade students scored below the basic level in science and 40% ranked below basic in math as determined by NAEP.

Given these statistics, it becomes obvious that California needs to drastically rethink it’s teaching methods and policies for K-12 math and science. As energy production, global warming, water purification and other scientific issues become more common to the 10 o’clock news, and therefore more salient in the public mind, we need to also focus on preparing the coming generations for the problems we are going to leave them. Also, the United States Department of Labor has recently shown that math or science preparation will be crucial to successfully competing for a job in 15/20 of the fastest growing occupations right now.

The President is also focusing national attention on scientific research, innovation, and math and science education. In a speech at the National Academies on April 27th, President Obama promised to make U.S. students the international benchmarks in the next decade by doubling budgets at certain science and technology agencies, policy change to enhance math and science education, and beginning to allot more than 3% of the nation’s Gross Domestic Product (GDP) to research and development. Obama said he wants to involve everyone from governors to parents to students to help increase support for science and technology and the quality of teaching. Supposedly 5 billion dollars is available in federal funds to help states improve their math and science teaching.

This is well and good, but throwing money aimlessly at the issue won’t solve anything. Bills like ACR 88, creating task forces to investigate effective policy change and inform the legislators, are the correct first step to tackling science and math education reform.

If any of you readers live in California, I urge you to write to your assemblyperson telling them that you believe we need science and math education reform and that you want them to support ACR 88. For any of you that are ACS members, they made it supremely easy for you. Simply go to http://www.act4chemistry.org/action/STEMtaskforceca/ and enter the relevant information. They will automatically send it to the correct representative for your district depending on your address. In fact, they even wrote the letter for you too!

Comments PLEASE. As a California public school survivor for my entire academic life, I have been through (and seen the failings) of the system first hand. I have some ideas on how to fix the issue, but I want to hear from ppl not in California too. Leave your two cents on what needs to be done to improve K-12 science and math education. Move calculus to required at 10th grade? do away with optional general physical sciences and the like? make everybody take biology followed by chemistry and then physics? in that order? what about elementary school? when to start teaching the scientific method? If 5th graders get sex. ed., should they also get newton ed.?

Lets see your ideas.

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Open Access Brainstorm

So I know that the classic subscription vs. open access journal debate has been going on for a long time, but every now and then something pops up to bring it to the front of my brain. This time, it is a tongue in cheek segment on PhD comics called:

Nature vs. Science pt. 1
Nature vs. Science pt. 2
Nature vs. Science pt. 3
Nature vs. Science vs. Open Access

I remember a year back, at ACS New Orleans, sitting in a chem. ed. session and hearing a couple editors from nature talk about the move away from print journals, and the increasing popularity of open access journals.

Admittedly, in the beginning I was all for open access journals. I greatly disliked the fact that journals, and the editors running them, are get to decide what science is “best” when they are likely not doing any research of their own. It seemed (and to a small extent, still does) an awfully ridiculous concept: we do original research, give it to journals for free, and they bundle a lot of it together and sell it back to us. I mean, I think certain people went to jail not too long ago for running schemes of that style.

But now I have started to think otherwise. I don’t think open-access journals will be the answer (at least not in their current state) simply because we are…lazy. Bare with me for a bit, and I will explain.

You see, I think that open access journals would ruin the prestige hierarchy of journals and they would all devolve into something like arxiv, which regularly get crackpot submissions like Marinov’s element 122 claim. Now I am not trying to speak against arxiv here; it is important and useful, and has it’s place among our tools for disseminating scientific knowledge throughout the community. However, Marinov’s paper is a good example of why serious peer review is necessary prior to publication.

Now some open-access journals like Plos One employ a technical peer review to filter out that sort of science-ish junk, but their revision does not look at the impact of the research. Without this, all submissions that pass a technical review will be published (eventually). Thus the selectivity, or prestige, of a journal is lost.

Why is such a thing important? I mean, why do a handful of arbitrary journals get to have all of the top papers published in them? If we didn’t charge for the journals, would we care which journal published the “big” papers? Well, I think the answer to that question is, yes we still would care. The fact is that we use the selectivity of the journals as a measuring scale of the research itself. We tend to read mostly the top journals in our field because we can skim the cream off the top relatively quickly and easily.

No one would ever have time to wade through 20 journals of physical chemistry, reading paper after paper, wondering if/where that ground breaking discovery was published. We would rather open up Nature and find out in 50 quick pages. Now I am not talking about a graduate student reading up on the specific idea he is working on and going through hours of literature searches. That isn’t going to change anyways. I am talking about the really big, important discoveries that would otherwise get buried under the volume of less important research that is published at the same level because impact is not considered.

How many bucky-ball like discoveries would have been overlooked because of distracting papers on stuff like Metal Oxide Films Produced by Polymer-Assisted Deposition for Nuclear Science Applications?

To get around this, some people have suggested letting people vote on the best or most important papers published, in order to determine impact that way. So instead of a journal gaining prestige, the paper itself does. This does seem more…correct, to me, than the current system. However, I wonder how well this will work. Even if the voting is limited to scientists, you still run into the problem of not everybody reading every paper (to ensure educated voting).

So say people simply submit their favorite papers into a poll: I submit one, Mitch submits one, Noel, you, your friend, etc. Say tons of people submit their favorites. Lets say, by some stroke of mad luck, that enough people submit papers that you feel you have a good sampling of the population, but not so many people submit papers that you feel your voters would never have the time nor interest to read each one. The voting may work the first time. It may work the second time. Hell it may even work a third time. But soon, like certain social bookmarking sites, some people will submit more often than others. After a while, the majority of the submissions consistently made by the same group of people, over and over again. Eventually, people only start to read papers submitted by their favorite submitters…because we are lazy.

So, Plos One, the “few individuals at the top journals that have all the power” are back, and the system hasn’t really changed. Except…oh wait, these guys aren’t paid to do a good job. Nobody in this system is paid to do a good job, w/o subscriptions. Unless, seriously, the journal can pay it’s editors through advertisement revenue. I wonder how well that will work. I figure it may work well at a small scale…a few open-access journals here and there. But scientific journals make up a fairly large industry: can it really be supported through banners and flash and many, many, many, many, many, many clicks?

Let me know what you think.

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Breaking Stuff for Science

Most chemists will agree, a chemical spill on the floor is one of the most annoying things to have to deal with in a lab. With LBL policy, you have to adhere to the SWIMS protocol: Stop work, Warn others, Isolate the area, Monitor yourself, Stay in the area. Not to mention using the correct spill kit, dealing with all the paperwork of the spill and the opening of the spill kit, explaining to the safety people what happened and why (hopefully) it wasn’t your fault, etc.

Aside from making sure your people are competent and well trained, not much is often done to prevent spills. Engineering controls such as secondary containment, fume hoods, capped reagent bottles, etc. work well when people remember and plan to use them. All too often, we see good chemists forgo extra safety steps for speed or just plain old laziness. Sometimes, people get badly hurt not because they were bad chemists or bad scientists, but because they really needed to catch the 6:40 train that day.

What we need are more safety devices that prevent the accident caused by a failure of the preventative safety measures from being very dangerous. For example, take these safety-coated reagent bottles from VWR. They have some plastic coating (PVC I think) outside of the glass to prevent spills even if the glass shatters. Sure some solvents would eat through the coating, but it would still buy you time to contain the spill, or evacuate the room if necessary.

Recently, with LBL’s current safety kick, our lab ordered 40 of these babies to replace our older reagent bottles. Interestingly though, the coating is really hard to see. In fact, when we first examined the bottles there was a dispute between some lab members as to whether we received the correct shipment or not.

Here is how the bottle looked, next to a typical graduate student size scale:

Being scientists however, Mitch and I knew that we couldn’t just take VWR’s word that we now had safety-coated reagent bottles.  We needed to test whether it really had the safety-coating, whether the coating would actually stay intact after an impact strong enough to break the glass inside, and whether the coating would feel weird if we poked with our finger.







So, using my safety training, I put the reagent bottle into a plastic bag, and put the plastic bag inside a phototray. Note the secondary and tertiary containment.






I went and found a big wrench, donned my safety goggles, lab coat, nitrile gloves and put the soon to be destroyed bottle durability testing apparatus into a fume hood with the sash half open.  I then proceeded to smash it to pieces. It was a good day of science.

Here is the result after a good beating. The safety-coating is quite clearly visible now, along with the area where the hole would be, if the coating wasn’t still covering it. The interior glass shattered as expected, but the safety-coating simply flexed a bit and recovered. Also, no sharp pieces of glass pierced the coating, so the contents of the bottle would have been contained. It took a significant amount of effort with some sharp tweezers to illustrate the intact film of the coating. We also confirmed our hypothesis that poking the film with our finger would feel weird. The bottle met our expectations in all tested categories. It also looked really cool and took a great picture.

So in our effort to make the lab safer, we tested and confirmed the usefulness of these safety-coated reagent bottles in an easily repeatable scientific experiment. Tests would have been done in triplicate, however funding was abruptly cut off when we attempted to share our findings with others in the lab.  We recommend the safety-coated bottles for use throughout the chemistry lab. All waste was disposed of in coordinance with EH&S protocol.

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Teen Chemist and Splenda

For as long as artificial sweeteners have been used, there has been a varying level of controversy over the safety of their use; both for humans and the environment in general. Saccharin and Aspartame have been plagued by health concerns raised by researchers for decades. Most studies have shown that only in very high concentrations are they dangerous, however few long term (>10 years) studies have been completed, so lower dose, chronic exposure has yet to be rigorously  investigated. Currently, most diet sodas use aspartame and saccharin, including my favorite, Coke Zero. Another very popular sugar substitute, sucralose has begun to steal the spotlight away from aspartame in recent years, taking over popular drinks like Crystal Light, Tim Horton’s and Starbucks coffee.

The chlorinated sugar substitute called sucralose (commercially marketed as Splenda (TM)) was first synthesized in 1976, as part of a collaboration between Queen Elizabeth College in London and the Tate and Lyle Chemical Company. It is manufactured by the selective chlorination of sucrose, in which three of the hydroxyl groups are replaced with chlorine atoms. Supposedly the graduate student, Shashikant Phadnis, working on the synthesis misunderstood his professor’s request to test the chemical as a request to taste the chemical. Just goes to show, sometimes to make a lucrative discovery, a chemist must take the ultimate test!

Whatever happened, it has been found that Sucralose is approximately 600 times sweeter than sucrose, and since being introduced in the USA in 1998, has become one of the leading sweeteners on the market. One of the main reasons for this is that studies have shown that sucralose is highly stable; it doesn’t break down easily due to heat so cooking with it is safe. It also doesn’t dechlorinate over time, photo degrade under visible light, or biodegrade with common bacteria. It is also very insoluble in fat cells, so all of us Americans don’t have to worry about getting a heart attack on the treadmill (at least not from sucralose!). In fact, sucralose is so darn stable, it doesn’t even get broken down in waste treatment plants.

Meet Smitha Ramakrishna, a senior at Corona del Sol High School in Chandler, Arizona, who has been doing research at Arizona State University about sucralose’s inability to be broken down and how this make affect the environment. At only 17 years of age, she has been researching sucralose for nearly 2 years, as part of her greater goal of trying to help with global water issues. She also founded an organization named AWAKE, which is dedicated to increasing her community’s awareness about water-related issues.

She has found that after subjecting sucralose to treatments similar to those used by waste water treatment plants, the sweetener resisted bacterial digestion. Only after a long time and under UV irradiation in the presence of high concentrations of titanium oxide (TiO2) did the sugar break down. Considering that few plants use these methods, the majority of sucralose in wastewater enters the ecosystem. She doesn’t say for sure what effect this will have, but says that preliminary studies suggest high concentrations of sucralose may poison fish.

See more here: That Splenda you’re drinking will be in our water supply for a while

Personally, I think people should use xylitol more. First studied in the 1970′s, almost no negative effects have been found due to ingestion of even 400+ grams a day (imagine 400+ grams of sugar! BLECH!) and many positive health effects have been proven ranging from plaque-reducing effects to boosting your immune system. It is about as sweet as sucrose, and has 2/3 the caloric content.

That said, I am still gonna go get me a coke zero.

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Light Powered Motor and Experiment Vlogging

Most of you probably read the last issue of C&EN with the spiffy carrot loving cover story (good for me because I love carrots, but have never tried those ugly-looking BetaSweets). Inside, however, there was an extremely interesting little article in the “Science and Technology Concentrates” about light-driven pulleys turning a plastic motor.

Now photo mobile polymer materials have been around for quite a while, at least from my perspective seeing as how I wasn’t even in highschool when the big Nature paper came out. Some might remember the Nature 1999 Sep 9;401(6749):152-5 Koumura et al. paper titled “Light-Driven monodirectional molecular rotor”. Although back then, the rotation was monodirectional around a C-C double bond in a chiral, helical alkene. It was activated by UV light or a change in temperature and the motor was based on light-induced cis-trans isomerizations that caused 180 degree rotations followed by thermally controlled helicity inversions, which basically nullified half a rotation. Four isomerizations resulted in 1 complete cycle.

Well this was pretty darn cool but we’ve come a long way since then. As expected, and as Koumura said, structurally modified chiral alkenes played the central role in the development of these molecular motors that were beginning to interest the MEMS people (MEMS stands for Micro-Electromechanical Systems…I am pretty sure).

In J Am Chem Soc. 2003 Dec 10;125(49):15076-86, ter Wiel MK et al. introduced the worlds smallest artificial light-driven motor using 28 carbon atoms and 24 hydrogen atoms.

Reprinted with permission from American Chemical Society: Journal of the American Chemical Society (Nov. 2003).

It also had a dramatic speed increase over the original designs, at a whopping 18s half-life at the fastest step. Even if it wasn’t going to be turning any relevant loads any time soon, it was a dramatic improvement over the original concept 4 years earlier. Still, even though some clever O-chem tricks made the motor better, it still operated on the same 4-step cycle that Koumura’s did back in 99′. Even recently, in Org. Biomol. Chem., 2008, 6, 507 – 512, DOI: 10.1039/b715652a, Pollard et al. report on substituting naphthalene moieties for phenyl moieties, in order to better control the speed of the motors, and to enable the design and synthesis of more complex systems.

Meanwhile, the MEMS people came up with interesting designs similar to this:

“A five micron wide resin structure, with a shape resembling a lawn sprinkler, rotates when illuminated by a laser beam. Tiny rotors like this one may someday power micromechanical systems (MEMS), or twist molecules to measure their mechanical properties.” Reported by: Péter Galajda; Pál Ormos, Applied Physics Letters, 8 January, 2001.

There was quite a bit of work done focusing on creating rotors that responded to laser light, although the practical applications of such devices aren’t as numerous as the devices that…well don’t require a coherent, collimated, polarized light beam to operate. Or at least they weren’t until Peidong Yang’s came around with his nanolasers.

Unfortunately, all of these motors share the drawback of being unidirectional. It was until recently, with Ikeda’s et al. paper in Angew. Chem. Int. Ed. 2008, 47, 4986, that a very cool and new method for directly converting light into mechanical work. Basically they drew on the fact that azobenzene derivatives, when incorporated into liquid crystals, can have an isotropic phase transition induced isothermally by irradiation with UV light to cause trans–cis photoisomerization, and that the reverse transition can be induced by irratiation with visible light to cause cis-trans back-isomerization. This photoinduced phase transition
led to successfully reversible deformations of liquid crystal elastomers containing azobenzene chromophores just by changing the wavelength of the incident light.

Now this by itself doesn’t a motor make. There was one large problem: the liquid crystal elastomer had to be made into a film or “belt” for a motor. However, the LCE film by itself wasn’t mechanically strong enough and tended to crack after short light irradiation at high intensities. So to fix this issue, they simply laminated the LCE film with flexible polyethylene sheets. I love this type of simple solution to what could have been a convoluted problem. This is very much like what Mitch and I tend to do.

*Note that they did do a study of increasing light intensity and it’s correlation to the mechanical force generated by the film. They found that “the maximum force and the increment rate of the generated force are enhanced with an increase of the light intensity.”*

So what happened? Well check this out:

Thats right. That is an actual light-driven motor NOT on the micro-scale. The diameter of those pulleys are 10mm on the left and 3 mm on the right. Sure it isn’t going to be competing in any races at the moment, but it could still be amazingly useful in the future. Light, straight to DC? That would be pretty darn awesome.

PS. Tomorrow is the first day of the experiment Mitch and I are running. Since we can, we will be broadcasting the first live cyclotron experiment out over the interweb. This may be one of the first live nuclear physics experiments broadcasted. Other then that, it is just cool. SO we will have it up all 24 hours as a “live vlog”.

Feel free; hell feel obligated to stop by, leave a comment, chat, ask questions, offer constructive or destructive criticism, whatever. Maybe ACS will pick this up as a new way to present new research: present it as it happens! Live!!!

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