Friday, October 29, 2010

Good Advice

The Curious Wavefunction has a review of a biography of the Indian chemist Chintamani Nagesa Ramachandra Rao (known as C N R Rao). This quote pretty much speaks for itself, so I will present it unadorned without further comment:
"So how does one do high-quality research in a resources and cash-strapped developing country? Rao’s approach is worth noting. He knew that the accuracy of measurements he could do with the relatively primitive equipment in India could never compete with sophisticated measurements in Europe or the US. So instead of aiming for accuracy, Rao aimed at interesting problems. He would pick a novel problem or system where even crude measurements would reveal something new. Others may then perform more accurate measurements on the system, but his work would stand as the pioneering work in the area. This approach is worth emulating and should be especially emphasized by young scientists starting out in their careers: be problem-oriented rather than technique-oriented."

Garbage Patch Vacuum Cleaners

Back in June I wrote about Electrolux plans to retrieve plastic from the various Garbage Patches in the oceans and turn them into vacuum cleaners. Somehow I was under the impression that the plastics was going to retrieved and then thermoprocessed into the parts needed for the vacuum cleaners (a task with a very challenging set of issues as I noted earlier). However, that doesn't appear to be the case - the plastics appear to be merely surface decoration on an existing cleaner.Each vac is made up of pieces collected from each ocean. Nonetheless, the vacs are attractive, but certainly an immense amount of energy went into collecting this relatively miniscule amount of plastic, all for a cute PR plug.

Thursday, October 28, 2010

Is this safe to eat?

Due to the massive storm that hit the Midwest earlier this week, we lost power at our house for 18 hours. After it came back on, we did the usual - reset the clocks, purge the air in the water lines (we have a private well - no electricity means no water means the system loses pressure and lets in air) and then the nasty task of triage in the fridge: what do we keep and what do we toss.

In a previous employment situation, I worked on developing a time-temperature indicator. Perishable foods are sensitive to both time and temperature - you can't keep food safe forever even if the storage temperature is ideal - the degradation kinetics still keep clicking, albeit slower at lower temperatures. As with any chemical reaction, the kinetics are governed by the Arrhenius equation:r = A exp (-Ea/RT), although it is usually plotted on a semilog plot where the slope is -Ea and the intercept is ln(A). The higher Ea is, the more sensitive it is to temperature variations.

So given this, we looked in the fridge. We had cups of yogurt (expiration date in about 1 week) and cups of pre-made pudding (expiration date sometime next year). You may be shocked, but I pitched the puddings.

Why? Keep in mind that these are all perishable food items that need to be refrigerated at all times - that means that at room temperature, they have a short shelf life. But since the puddings have such a long shelf life at proper storage temperatures, that means they have a very high activation energy, and that they suffered far more from the fridge warming up (it was 55 oF when the electricity came back on.)

Similarly, in the freezer we had some ground beef that is stored in a modified atmosphere package, a package which also elevates the activation energy for the degradation. We ate it last night, or else I would have pitched it.

Modern food preservation techniques are all prone to this problem: they increase the shelf life at proper temperatures but do little to help at abusive storage conditions. People see the long shelf life dates and feel reassured.

A Foreign Body

About once a year there is a medical image published in the New England Journal of Medicine that is memorable. Today's image is just that - one that you don't need to be much of physician to diagnose: The first line of the caption: "A 35-year-old man presented to the emergency department with profuse rectal bleeding, abdominal pain, and an altered mental status..."


Wednesday, October 27, 2010

How to Get Around FDA Regulations - Legally!

It can be done and now that the Supreme Court has given its stamp of approval. The Supreme Court has now stated that it is o.k. to import drugs from a non-approved source foreign source and use them for their intended application. I never thought I'd see the day, but it has happened.

Oh, before I go, I forgot to mention the one little restriction: this only applies if the drug are intended for a court-ordered execution!

Apparently being concerned about the purity of the chemicals, their storage, etc. is just not an issue if you are being sentenced to death. If you've worked in an FDA regulated environment, the reasoning in the Court's Order is going to get you like fingernails on a chalkboard:
"There is no evidence in the record to suggest that the drug obtained from a foreign source is unsafe."
Try telling that to the FDA inspector next time they audit your facility and watch them die laughing. Sorry, if you are making a regulated drug/device, the burden of proof is on you to show that it is safe - the presumption is that it is not safe, even as the Supreme Court here attempts to reverse that.

Obviously this won't change anything except for the suppliers in this ultrasmall niche market. And it certainly was a creative attempt by the lawyer to delay the execution, but I imagine that more than a few people at the FDA heard about this and were aghast as it really was a complete reversal of their regulations.

The Coolest Thing You Can Do With a Polymer - Set Yourself Ablaze

Of course, all that heat is not very cool.

The Gray Matter feature over at Popular Science has a brief description of the art and skill of setting stunt people on fire for movies. Not to be outdone, the author sets himself on fire. Video included.

The combustable material is a sodium polyacrylate gel, which is a novel use of this polymer that I normally think of as being used for a more wasteful purpose. Being that this trick will be tempting to plenty of people who think immolation is neat or are otherwise attracted because of pyromaniac desires, I'm not going to go further details about the polymer or where to obtain it. Just watch the video, say "Kewl" and move on.

Tuesday, October 26, 2010

Shuffling up the PET Business

Buying and selling chemicals companies and divisions continues. The latest announcement is that Eastman is getting out the PET arena entirely and selling their plants to DAK.

It appears that DAK intends to keep operating the plants, so this is not a "jobs going to a foreign country" story, just a division going to foreign ownership story. The report from C & E News had a sentence that I am questioning.
"Eastman is the last publicly traded U.S. company to be involved in the PET business."
First, it is an odd distinction to make, as why does public/private matter? But I also recall that when I was working at 3M, they made a lot of their own PET for captive use in their tenter lines, largely to support the mag-media business [*]. 3M shut much of that down in 1995, so they may have cut back or eliminated the internal PET production as well. The PET also was use for backings on adhesives tapes and other 3M products but they certainly didn't have the volume of the mag-madia. If any knows if 3M still makes PET internally and feels like stating so, I'd be curious.

[*] For you young 'uns, before digital storage existed, data was storage in an analog form in magnetic materials that were coated on polyester film. Sometimes it was in the form of a circular disk (kinda like a DVD) and sometimes it was in the form of a long ribbon that was wound from one spool to another. I promise to say just one more bad thing and then I will stop scaring you - the spooled ribbons did not have random access!

A Tale of Two Tenters

It was the best of times, it was the worst of times...Let me stop right there before Charles Dickens' ghost comes back and starts haunting me this weekend.

I ran across this old relic (an umbrella)
and it reminded me of my choice between two tenters [1] that I once made. I was finishing school and had begun interviewing. One of the positions was in Hopewell, Virginia at the ICI PET film plant. I was given the umbrella at the end of the day when the rain that had been threatening all day finally let loose. My host gave me the umbrella to keep my suit dry, although the rain was bouncing off the parking lot surface so hard that it did little good. Regardless, I still got a nice keepsake that only now is starting to fail. (Also, a million manhours without an OSHA reportable injury? That is impressive.) ICI is no longer which I still find shocking since at that time it was the 4th largest chemical company in the world. I think the PET plant is still operational, now being run by DuPont.

The other position was at the Hercules PP film plant in Terre Haute, Indiana. Hercules is also no longer in existence, but the plant still is. In this case, Applied Extrusion Technologies bought it, and looking at the satellite pictures, seems to have expanded it considerably. For a number of reasons, this is the job that I took.

I always wonder how life would have turned out if I had taken the other job. It is truly impossible to say. I left Hercules after 10 months. Some of the reasons for that may not have existed if I took the ICI job.

A coworker is of the opinion that life is made up of only about 5 serious choices (Which college? Which career? Which spouse? Which job? Kids, yes or no, and then how many?) and the rest is fluff. Certainly those choices are the big one and few people appreciate the simplicity of his viewpoint, but when I remember the tiny little twist one day [2] that allowed me to meet my wife, I can't help but feel that the butterfly effect is still mighty significant.

[1] Plastic films are made either by the blowing a large bubble and slitting it, or by the tenter process. In the latter, the film is stretched first in the machine direction by using rollers that a running faster at the output that at the input. This film is then fed continuously in the tenter (the second "t" is silent), the piece of machinery that stretches film in the cross-direction by grabbing it on the edges with clamps that are on a ever widening track.

[2] My advisor was out of the country and a secretary in the department office was typing up a paper for him (yes, on a typewriter!). She couldn't be sure what one of the handwritten words was, so she called me. I went down to the office, deciphered the word, and turned to leave. At the same moment that I opened the office door, she was walking down the hall right past the office...

Monday, October 25, 2010

Maybe Artificial Human Skin Does Exist

A little over a month ago I wrote about the difficulty of testing medical adhesives. The challenge is that human skin is difficult to mimic, not only because of it's low surface energy, but also because it is elastic - most adhesives adhere well enough to deform it and that work of deformation is always included in the measurement.

So here's to me embarrassing myself by finding a couple of papers that claim to have developed a suitable substrate for testing medical adhesives. One is in the Journal of Adhesion Science and Technology (2007, Vol. 21, No. 15, 1497-1512) and the other is in The International Journal of Pharmaceutics (2009, Vol. 368, No 1-2, 83-88).

It seems pretty simple, cook up some gelatin in water and NaOH, add some glycerol, some fatty components and then finally crosslink the whole mess with some formaldehyde. I've got to try some of this soon, as it will great to (verify and) know about before we get another medical adhesive project.

And best of all, my back will thank me. (See the earlier post if you don't get this reference.)

Chain Folded Polymer Crystal Picture

This is the first time I've seen a color version of a picture of a chain-folded polymer crystal. I like it a lot. It sure beats the black and white drawings that I put in my dissertation. Source

Except in exceptional circumstances, polymers do not crystallize in an extended-chain conformation (spaghetti in a box) but instead are repeatedly folded along the chain and re-enter the crystal. You can see this in the blue and green chains above - the red ones appear to be too short to fold over and re-enter. The length of the chain folds depends on the temperature and can be changed by annealing - another topic for another day.

This is from a simulation effort, but it still is better than the idealized hand drawings like this:

Friday, October 22, 2010

It's Not Easy Being Green

Polylactic acid (PLA) and other biodegradable and bio-based polymers certainly have an apparent advantage in "sustainability" and perception of "greeness", but a new report (Note:this link is to an open access summary and has a link to the original report which is accessable by subscription/pay-per-view) concludes there are a slew of disadvantages that need consideration as well.
"Biopolymers trumped the other plastics for biodegradability, low toxicity, and use of renewable resources, but the farming and chemical processing needed to produce them can devour energy and dump fertilizers and pesticides into the environment..."
In other words, when a life cycle analysis is completed, the picture changes. In particular, production of the various biopolymers requires the use of fertilizers and pesticides, extensive land use for farming, and then there is the chemical processing needed to convert the plants into the final plastic.

What really caught my eye is that the biopolymers were the largest contributors to ozone depletion.

Somehow I don't think that this report will be the hot topic in the environmental blogs this weekend.

Plastics - They Have a Future, but no Futures

I've written earlier this year about my concerns with trying to run plastics through the futures markets, but now it appears that maybe these concerns are shared by others. The London Metal Exchange announced that due to a lack of volume, futures contracts for plastics will no longer be carried.

Despite the use of the term "commodity" to describe HDPE, LDPE and other polymers, they truly are not commodities, what with the numerous grades that exist.

Thoughts on Losing Electricity

I've not worked in a HDPE manufacturing plant, but I can imagine that this had to be tough to deal with: Chevron Loses Power at Pasadena, Texas, Chemical Plant.

My first job was located at a PP film plant in Terre Haute, Indiana. A small group of us were part of the corporate R & D structure, but were located at a manufacturing site to get exposure to the function. To further drive home that we did not work for the manufacturing plant, we had offices in a double-wide trailer (yes, I was trailer trash for a year). These high end accommodations were located just outside the tower where the blown PP film was made. One hot summer day there was a dip in the power, just enough to blacken the computer monitors but not enough to reboot them. A second or two later, we heard the "gunshots": BOOM, BOOM, BOOM, BOOM, BOOM, BOOM. All six bubbles had popped.

A colleague said to stay put, but being naive and innocent, I went anyway. What a mess. I just started grabbing film and pulling it to the garbage. I don't recall how many hours it took to clean everything and then get all 6 lines restarted, all because of a 1-second dip.

I can't imagine the problems that could occur in a large manufacturing site with a total outage. Certainly the plant is designed to safely shutdown (failsafe), but the restart would be the bigger concern.

Monday, October 18, 2010


I finally found a route to taking questions. The link on the left hand side (under the "Who is this Guy" heading) will take you to a page on Formspring where you can ask questions on polymer science, engineering or anything else. You can ask them anonymously or not, just keep in mind that the answers will be public.

Wednesday, October 13, 2010

Never Mind

Just a quick note: The R & D 100 Awards were recently announced. In the Material Science category, one of the winners was the polylactic acid, 100% compostable bag that Frito-Lay uses for Sun Chips. Actually, make that "used", as F-L just announced they are pulling from the shelves because of excessive noise.

So who has the bigger egg on their face? F-L for pulling the bag for complaints that were known before the bag even hit the shelves, or R & D Magazine for giving an award to a product that didn't last a year?

Pushing the Laws of Science and Man

I was discussing the current economic conditions with a colleague and we gathered a new insight. We both commented on how any of a number of various financial institutions had been pushing the limits of the law - yes, in some cases, clearly exceeding the law, but in many cases, getting as close to the limits as possible.

And then came the insight: my colleague and I both do the same thing, only in our case, we are pushing the laws of science to their limits. We can't break them [1], but we push them to the limits, let others know what we found, and then they try and go that much further. That's what R & D is all about. [2]

Back to the financial problems, new laws will/could/should prevent those past abuses from reoccurring, but the outfits will also start pressing the new laws as far as possible until there's trouble and the rules change again. Consider it R & D, but in the legal arena.

[1] We've tried, oh how we have tried, but the science police really do a good job on enforcing them.

[2] As Uncle Al has said, 2/3's the fun of chemistry is discovering the rules, the other half is in breaking them. Physicists, being better at math, have 16.7 basis points less fun.

Calling Mr. Murphy...

Or maybe calling this hindsight bias would be better.

From ChemInfo
"The head of Royal Dutch Shell says that his company would never have made the mistakes that led to BP's devastating Gulf of Mexico oil spill.

[Shell CEO Peter] Voser told an oil conference in London on Tuesday that from what he knows today "Shell clearly would have drilled this well in a different way and would have had more options to prevent the accident from happening."
I have no doubt that BP and its subs did a number of things wrong, but for someone to say that their company is in all ways better? How can someone get to be CEO and never have learned that people don't always follow the SOP? Or that unexpected things will just happen despite your best efforts to prevent it? This guy better be hoping and praying that nothing bad happens on the remainder of his watch. Eating crow is never tasty, and crow with spilled oil on it would be that much worse.

Tuesday, October 12, 2010

The Supreme Court Looks Into Free Basing Cocaine

About once a term, the US Supreme Court takes a case that has a particularly technical angle to it. They always horrify me as the Justices get to display their ignorance of science, and also their ignorance of their ignorance: (Chief Justice Roberts: "2 + 2 is somewhere between 3 and 5, right?").

This term they now get to decide if laws against "cocaine base" include every base of cocaine of just "crack". The difference can be important as the penalties are much higher for crack than regular cocaine. (50 g of crack will get you ten-years, but you need 5 kilos of regular cocaine to get that same term.)

Cocaine is normally supplied as the hydrochloride salt, kinda like in the picture below, but imagine that the Cl- is floating around somewhere:

Crack cocaine is made by adding water and baking soda, while the free base is made by using ether and some other strong base[*]. The end result is chemically the same, but apparently a number of the district circuit courts have reached different answers on how important it is. And so crack cocaine and free basing will have their day in Court. I'm not sure when it will be just yet, but I can assure that I will have something to say about the appalling lack of science that will be found in the courtroom.

[*] You can obviously see now knowledgeable I am in these matters, huh?. Like I'm sure any readers here can do any better.

Don't Just Complain About Poor Patent Quality... something about it. Here's your chance. About a year ago, the US Patent & Trademark Office (USPTO) had a "Peer-to-Patent" program where pending applications were made available at the USPTO website. The Office was interested in understanding prior art relevant to the patent and took input from the public. At that time, the patents were limited to those in software and other technologies far removed from our beloved polymers. For reasons unknown, the program was ultimately discontinued.

However, it was just announced that it is being relaunched and this time will have applications quite different than in the past, including organic chemistry. I can't guarantee that there will be some polymer related applications, but it certainly would not be surprising if there were. If I do see anything, I'll be sure to mention it.

The biggest complaints about patents (overlooking the whole controversy about whether they help or stifle innovation in the first place) are that the prior art is never properly searched, thereby allowing patents to issue that never should have. By opening up the prior art searching to what would be effectively the whole world, it is hoped that the quality would be improved.

Monday, October 11, 2010

Social Networking in the Plastics Industry Grows

The Urethane Blog is reporting that BASF has a YouTube "station" (I believe that they are properly called "channels"), while Dow Chemical was providing regular Twitter and Facebook updates at the "K" show. BASF actually has a full page on their website devoted to their social media efforts. [1]

I'm not expecting much from these efforts. They'll probably look pretty much like the PR pablum that marketing departments put out on a regular basis. In other words, it will be the same output as usual, but only the medium will be different. Like the ads that we all learn to ignore on most websites. They will certainly be able to brag to their management about all the hits they are getting, but stickiness and converting those hits to actual business is extremely difficult. Ask me.

Putting out an interesting blog (or whatever type of Web 2.0 option you desire - remember podcasting?) is challenging. While I am employed, this is still my blog and so I can experess stronger opinions and address more controversial topics than a conservative business entity can. The latter would most likely have to run everything through a committee and probably the legal staff too, further reducing any freshness, vivacity and interest.

I've been pushing for a strong blogosphere in the plastics arena for some time. It is progressing at a painfully slow rate, but there is so far to go. Let me give you some details. According to Google Reader, I have 27 regular subscribers. "In the Pipeline", probably the most popular blog on the chemical side of the pharmaceutical industry has over 100 times that, and yet gets only between 20 and 50 comments on a post. Call it a 1% response rate. About the same as direct (junk) mail if I recall correctly. So I'm not surprised in the least that I get few comments. This is all part of a very narrow funnel. If 1% of the readers are likely to comment, it is probably another 1% of that small cut that would actually be interested in doing business.

But it's really worse than this. Total readership is measureably higher. The Sitemeter at the bottom of this page shows that I am averaging about 200 direct accesses per week. (Click on the icon and you can see for yourself. It's fun to see visitors from all across the planet.) Depending on how you slice it, the response rate is therefore at least an order (if not 2) of magnitude worse. [2]

So best of luck to these new commercial undertakings. The numbers above are pretty depressing and that is for a site that tries to be interesting and maybe even a little controversial. Imagine what it's going to be like for a PR machine.

[1] I have a very difficult time accessing much of these site from work. The IT department only allows video downloads between 8 AM and 10 AM and I'm not going to plan my whole day around that. (There's actually more restrictions than that too, but I'll leave those details for another post - maybe.)

[2] Despite what you may read about the blogosphere being the worst of the wild west with all these anonymous postings leading to endless on-line arguments and name-calling and..., most people are just lurkers - they show up, look and leave.

PMMA As An Automotive Windshield

About a year ago I wrote about polycarbonate's increasing usage in automotive windows, starting with sunroofs and then going to side windows. The coveted windshield is still aways away.

But now here comes an upstart: PMMA, i.e, poly(methyl methacrylate), i.e., Plexiglas. Modern Plastics is reporting on the use of PMMA as a glass replacement for cars. Only this not as a sunroof or side window or any of the less demanding applications. This is in the windshield. Of a race car.

Race cars certainly will put a larger stress on the window, and any rocks or debris that hits the windshield will certainly be far more likely to damage it, but race cars are typically used for just a few hours before they go back into the shop and get rebuilt for the next race. Long-term stability of the material is not an issue - the car won't last 10 years so why would there be any concern of the windshield yellows in 10 years? I don't see this as actually making that much inroad into the market.

Friday, October 08, 2010

What is Resin and What is Plastic?

I'm certainly not going to answer that question. If I'm going to get into something controversial, I'll take on the glass transition.

But the people over at PlasticsToday are more willing. One of the posted comments:
I had an instructor (retired now) who single handedly tried to correct the culture but even material suppliers use the term "resin" for their polymers. I’m part of his cult. The cult of the polymer people. Resin is sticky and we don’t like to work with it. Just say “NO” to resin (unless you manufacture gloves and harvest latex from rubber trees).
There's always the new viewpoint too: Resin is the Mayor of Moscow. (Were he to join the communist party, would people stop using the term "resin" much like swastikas are no longer used? Before the Nazi's used the symbol, it was commonplace and considered a good luck symbol.)

Thursday, October 07, 2010

The Strange History of Bubble Wrap

I was not aware of the long and twisted development path for bubble wrap. From Wikipedia:
"Bubble wrap was invented in 1957 by engineers Alfred Fielding and Marc Chavannes. Fielding and Chavannes sealed two shower curtains together, creating a smattering of air bubbles, which they originally tried to sell as wallpaper. When the product turned out to be unsuccessful as wallpaper, the team marketed it as greenhouse insulation. Although Bubble Wrap was branded by Sealed Air Corporation (founded by Fielding and Chavannes) in 1960, it was not until a few years later that its use in protective packaging was discovered. As a packaging material, Bubble Wrap's first client was IBM, which used the product to protect the IBM 1401 computer during shipment"
Wallpaper? Greenhouse insulation? It shows how hindsight is 20/20.

Wednesday, October 06, 2010

Sun Chips to Pull It's Noisy PLA Bag

The headline pretty much says it all. The Wall Street Journal, who you will recall shocked us all by mentioning and attempting to explain glass transition in an earlier report on the bag, is now reporting that Frito-Lay will continue to work on developing a quieter bag, but in the mean time, will go back to a noncompostable bag.

I still never understood how the aluminum vapor coat could be considered compostable.

A Rare Case where a Misnomer Might be Good Thing

The "rare earth" elements are not. Rare that is. The name is a misnomer arising from a bad translation of an ancient term. I can't be sure [*] but I'll bet that a number of congress people thought that because they are "rare" (again, they aren't) that it was easy to drum up support for a bill designed to reduce the US's dependency on China for these materials. The bill passed the house 324 - 92 so that clearly says that this is far more than a party platform issue.
"The US was once the world's leading supplier of rare earths, but it has produced little since its only rare earths mine closed in 2002. The nation now relies on access to supplies from China, which controls approximately 97 per cent of the world's rare earths.

China has achieved dominance in this area in part by imposing export quotas in 2006, which have steadily grown stricter. It has also encouraged rare earth dependant industries, like wind turbine manufacturing, to establish operations in China. The country reportedly cut its rare earths exports for the second half of this year by 72 per cent."

I just still have this nagging thought though that the misnomer probably helped the cause.

[*] There is no way that I am going to look up the transcripts of the subcommittee hearings and such to find out what our distinguished representatives in Congress thought of the term "rare earth". I'd rather read the "Journal of Heuristics" cover-to-cover than do that.

Tuesday, October 05, 2010

Plasticizers = Positive Drug Test?

About twice a year I get to blog about bicycle racing here without it being much of a stretch. This is one of those days.

Alberto Contador is in the sporting news, more and more each day. Alberto won the Tour de France for the third time this year. News broke late last week that one of his urine samples had tested positive for clenbuterol, a drug that can help asthmatics with breathing and in general boost the oxygen carrying capacity of the bloodstream. The test certainly raised eyebrows and made the news, but there wasn't a huge scandal associated with it because the detection level was very low. It was too low to have any therapeutic impact, it wasn't found in any of the previous days samples, the following days samples showed a rapidly dropping level, and it was entirely possible that he consumed the drug unknowingly in his food. (He specifically stated that it came from some Spanish beef that he ate - the drug can be found in animals products as it is often given to them to aid in growth.) As such, I and many others were willing to not immediately come to any conclusions about it. Given the ever decreasing detection limits for analytical equipment, testing labs are going to keep finding more and more of less and less. I personally think that eventually it will be impossible to completely ban any drug from sports - it will be necessary to ban them above a certain level.

But anyway, things got a little more interesting yesterday when the NY Times reported that the Tour de France champion also had high levels of plasticizers in his urine. Yes, those nasty little plasticizers that fearmongers love to hate and that are in most PVCs. It's not that the plasticizers have any known therapeutic properties, it's that they "could" have gotten there from a blood transfusion that he took. (His own blood of course, that was withdrawn well in advance of the event.) Or maybe he was sucking on a PVC toy that evening. Or he helped the team mechanic with dip coating his tools with PVC plastisol and accidentally drank some. Or maybe he was making polymer clay things in the hotel kitchen and the plasticizers went through his skin.

In any case, this second set of test results is a lot more suspicious to me, even if it is indirect evidence. I would imagine that this will quickly lead to a very close examination of any blood drawn during the appropriate time frame. Any failures there would certainly lead to a second Tour de France champion being dethroned.

And all because of a plastic additive.

On Units of Measure

Unit reduction is very commonly done. For instance, thermal conductivity is the heat flow per unit area divided by the temperature gradient. (W/m2)/(K/m) which reduces to W/(m K). So how come gas mileage figures aren't reduced to inverse area? Miles per gallon is a length over a volume which is an inverse area. 1 mpg is equal to almost 39,500 ft-2, so just multiply that appropriately. Anyone have the gall to start using this? (Not me! I was just thinking about on the drive in today.)

Monday, October 04, 2010

Crystalline Phases and More Crystalline Phases

Many (semi-)crystalline polymers are polymorphic, having more than one crystalline phase. These are usually academic concerns and not industrial. Polypropylene, for instance, has 3 phases that I am aware of, although I am not aware of any products that actually are constructed from anything other than the run-of-the-mill a-phase. The b-phase can be obtained with special nucleating agents and temperature control, but upon heating, will revert to the a-phase. I recall reading about the g-phase, but it always a minor constituent.

Now comes a new report about that odd duck syndiotactic polystyrene (the kind that can crystallize) that not only has an a-, b-, and g-phase, but also an d- and e-phase too. And in this report, they looked at how well the last two phases adsorbed hydrogen.

That is the most phases that I ever seen for one polymer. Quite impressive.

Friday, October 01, 2010

The Ultimate Science Article in the Popular Press

If you've read me for much more than a month, you know how much I hate PR blurbs and what is reported about science in the popular press. I can now die in piece after finally reading an article that got it right. Perfectly right. In every detail.

A Giant Among Molecules

Added A Giant Among Molecules to the blogroll. The Giant is a third year grad student. I like what is posted and wish it was more frequent.

A Clever Method to Prevent Spam on Chemistry Sites

We've all seen the various schemes to try and ensure that comments on a blog or registration at a website are being made by humans and not bots. CAPTCHA is very common: ChemFeeds has a clever twist: name that molecule:This is a terrific idea, as not only will it keep bots out, but it will also keep out people who have no clue about chemistry.