Category Archives: Chemistry Blogs

Deutsche Bank’s Sankey: Simple Scarcity Driving up Fuel Prices

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As everyone knows, the price of gasoline in the USA has been steadily marching up into the low US$3.00 per gallon range to achieve all-time high pricing.  Reliable sources state that the price run-up is due to simple shortage of supply. According to testimony from energy analyst Paul Sankey of Deutsche Bank, the US refines 17 million barrels of petroleum per day against a demand of 22 million barrels per day.  An interesting analysis can be found at the Oil Drum. 

We are in a very precarious position here. An oil shock caused by a catastrophic loss of refining capacity will result in a wild price spike (some estimate US$100/bbl) while gasoline is in the mid $3.00 range already and a major perturbation to the economy- or worse.  Unfortunately, we are bogged down in the ill-conceived GW-II, the second of the energy wars. 

Wherein Gaussling Laments the Demise of Chemical Photography

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A sad day it will be when the last image is captured on a photographic emulsion. The transition from chemical photography to digital photography is well underway.  Indeed, it is clear by a simple visit to a big box store that the amount of shelf space given to film cassettes vs digital cameras & accessories is rapidly tipping in favor of the digital.  Consumer demand is well past the cautious early-adopter stage in its evolution.  Many people are several generations into digital photographic equipment. 

I own a low end Hewlett Packard Model P.O.S.  digital camera with a 4.1 megapixel chip.  I suppose I’d be happier with it if it still worked.  Even when it did work, it was a P.O.S.  As long as nothing moved, the image was sharp and the colors were true.  But given the slow shutter response, the slow shutter speed, and the heavy power demand on the battery, using it was a maddening experience. Evidently a capacitor has failed because the flash fails to fully charge. 

Printing is still a chemical process, one way or other.  Printing consumables like paper and inks/dyes are a major cash cow for all of the manufacturers of printers. 

I do not consider photocopier xerography to be strictly digital imaging.  I consider it to be a form of chemical photography because, despite the use of computer driven laser arrays and electrostatics in image formation, there remains a deep and intricate art in the chemistry of the toner composition.  I have actually done some color toner R&D and can attest to the high art required in that field.

Th’ Gaussling laments the demise of chemical photography, at least on the camera side, because of the highly advanced color chemistry knowledge that will inevitably be lost. Lost because skilled practitioners in the manufacture of color films will retire, labs and plants will be shuttered, and the use of color films will dwindle to low volume.  Soon, say 20 years from now, only eccentric purists and “hobbyists” will capture images on emulsions.  Drug stores will sell off their developing equipment to people who drive VW Beetles in Guatemala and fill the space with racks of diabetic candy, NASA diapers, and $4.99 DVDs. 

Soon, the experience of dodging a poorly exposed image under the projector, swishing print paper in developing solution under red light, and experiencing the magic of seeing an image appear will be lost to future generations.  The smell of acetic acid and the darkroom clutter of wet film hanging from string will be but a distant memory of the “old ones”. 

When I get to the nursing home I’ll regale my fellow geezers and codgers with harrowing tales of nights spent outside at the telescope shooting time exposures with hypersensitized Tri-X.  They’ll nod off in boredom and I’ll switch on a Star Trek rerun and fall into a deep slumber while Kirk and Spock contend with the Tholian Web.  ZZzzzzz.

Where are all the BA/BS organic chemists?

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Over the years I have interviewed many hopeful candidates for a position of entry level BS/BA bench chemist in a synthesis lab.  Recently, I have interviewed a couple of candidates for synthesis chemist position and have refreshed myself with the challenge. 

It is surprisingly difficult to find and hire a decent candidate for position as a synthetic chemist at the bachelors level.  In fact, I am having trouble finding fresh BS/BA graduates that can show me the mechanism for the acid catalyzed hydrolysis of an ester, or can suggest a reagent for the reduction of benzaldehyde to benzyl alcohol.  These are fundamental transformations and a BA/BS in chemist should be able to go to the board and noodle through a little bit of arrow pushing.

Most of the candidates sent in by our favorite temp agency are analysts either by temperament or by experience.  Granted, analysts may be the meat and potatoes of the temp chemist trade.  But what astonishes me is the small number of candidates out there with more than 2 semesters of organic chemistry and an even smaller number with any inorganic lab experience at all. 

In previous searches we have looked for BA/BS people from an ad in C&EN.  Rarely did we find that students had taken an advanced organic class/lab, let alone an organic qual class.  I know that such classes are offered out there.  Are all of these bachelors level students who take advances coursework going to grad school or med school?  Maybe most of them are.

As a former supervisor of undergraduate research, I am tickled pink that bachelors students are getting experience with advanced equipment, but we still need to graduate people who can make a target molecule and fish it out of a product mixture.  I’m glad that Bobby or Suzie can do capillary electrophoresis or use a peptide synthesizer to make a decapeptide.  I just hope that a few students are learning how to take a substrate through at least two steps of a literature procedure synthesis and then purify by fractional distillation or a recrystallization.  Furthermore, I hope that chemistry departments are still hiring an occasional mainstream organic chemist or inorganic chemist who can pass along lab techniques.

Perhaps the bachelors organikkers are drawn to grad school for advanced education.  That is what I did.  But I’m still shocked by the number of bachelors level candidates I see that show very little retention of organic concepts, apparently the result of disuse in their junior or senior years. 

Part of this problem might be geography as well.  My region does not have the industrial legacy that other regions have.  Perhaps the situation might be different in NJ, CT, or TX. 

Sorry. I’ve filled the position, so don’t send a resume.

Boron Cosmochemistry

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Next time you wash your laundry with borax, pause for a moment and consider the path those boron atoms took to get to your dirty shirts.  The Big Bang started the universe with H, He, and maybe a bit of Li.  The rest of the periodic table had to be produced by nuclear reactions within the core of a star or during the explosion of a star.  This occurs through either the fusion of charged nuclear particles (nuclei included) or absorbed neutrons to nuclei, perhaps followed by a decay cascade.  Note to reader: astronomers are in the habit of referring to elements heavier than helium as a “metal”. 

In the core of a star there exists a complex kinetic circus of multiple simultaneus synthetic channels involving both atomic weight buildup and disintegration.  Nuclei less sensitive to the reaction conditions may accumulate and delicate nuclei like boron have but a fleeting existance and are consumed.  In addition to stability to the reaction conditions, particular combinations of protons and neutrons tend to be more stable and accumulate if only by the lack of propensity to decay. 

While the elements C, N, and O are cosmically quite abundant, at least in comparison to the rest of the elements (3 to 92), the elements Li, Be, and B (LiBeB) are relatively scarce. 

Because boron was too heavy for Big Bang nucleosynthesis and too reactive to accumulate in a stellar core, it’s cosmic abundance is low.  What little that is found did not arise as simple boron ejecta mechanically boosted into the interstellar medium by an explosion or as entrained mass from stellar wind.  It was formed from more abundant elements like CNO that had already been ejected- elements that would be subjected to a barrage of highly energetic particles.

LiBeB are thought to be “spallation” products from interstellar CNO collisions with cosmic rays.  From the linked chart, we can see that C, N, and O are relatively abundant.  So over a multibillion year timeframe of stellar evolution, early massive stars can live and die, dispersing metals into nearby space.  Accumulated heavy elements can then be exposed to cosmic ray fragmentation.  The source of the cosmic ray particles in these collisions is somewhat up in the air.  Some of the latest thinking suggests that these energetic cosmic rays yielding spallation products are from especially energetic sources like Wolf-Rayet stars or type II supernova events.  There is an indication that boron can come from two spallation channels- cosmic ray and neutrino-induced spallation of carbon. 

So, the picture thus far- boron arises from the energetic collision of particles outside of a star.  Heavier nuclei will fragment under cosmic ray bombardment and some combination of B-11 and B-10 are formed.  What is interesting is that this is a dispersive phenomenon.  By contrast, on earth, boron is found in deposits as the hydrate of the alkali metal salt of the oxide- Borax.  There are a variety of distinct mineral compositions that contain boron.  On earth, a bit of the dispersed boron was somehow concentrated into ore bodies.  This is where geology kicks in.

Hydrothermal action near subduction zones can dissolve borates in hot, pressurized water and deposit them at the surface where the solid borates come out of solution on cooling.  This process evidently partitions the isotopes of Boron slightly.  Over time the process continues until geological events interrupt the deposition process.  If the solubility of the borates is relatively low at surface temperatures and pressures, then weathering will not further disperse them into the hydrological cycle.  Thus they form a deposit.  Layers of sediment accumulate over the borax deposit and eventually geological processes move the layer underground. Eventually, uplifting, weathering, and mining makes the deposit accessible.  Through the miracle of marketing, distribution, and 18-wheeler trucks, this spallation product can be used to clean that unsightly mustard stain from your shirt.

News Flash! Most energetic supernova ever observed was detected in the galaxy NGC-1260 by Chandra.

Blam!

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There are quite a number of YouTube videos featuring explosions.  One that caught my eye recently features the reactions (explosions) of the heavier alkali metals, Rb and Cs.  The “experiments” could be legitimate, but with television you never know.  Then there is the lab demo of the reaction betwen bromine and potassium.  My personal favorite is the combustion of Magnesium in CO2 (Dry Ice).

Some years back I decided that I would treat my class to a demo on the reduction of CO2 with magnesium.  I had already done the Mg/CO2 demo before, but I learned in Bassam Shakhashiri’s book on demonstrations that the addition of a smidgen of potassium chlorate to the magnesium would assure that the Mg would ignite properly.  Make no mistake, Shakhashiri is much beloved in the chem educator field and rightfully so. His demonstrations are legendary.

I was a little uncertain of the wisdom of using potassium chlorate, so I decided it would be prudent to try out Shakhashiri’s modification in advance. One evening in my research lab I chiseled out a small indentation in a block of dry ice and added a Mg ribbon “fuse”, Mg turnings, and the recommended mass of potassium chlorate.  I ignited the ribbon and held the second dry ice block in front of me, ready to place it on the burning Mg.  As the burn reached the chlorate there was a blinding flash and a loud BLAM! When I opened my eyes I saw that the papers on the benchtop were ablaze and that the block of dry ice I was holding prevented burning Mg frags from lodging in my clothing. The air was cloudy with MgO dust, my ears were ringing, and expletives were flying out of my mouth.

Better that it happened in private than in front of 65 students. The students’ burns would heal.  But, more importantly, the damage to my reputation would have been horrific.

A few years later at an ACS meeting, in the mens room at the convention center in San Diego, I was standing at the urinal when who should take the urinal right next to me?  Bassam Shakhashiri.  I pondered the opportunity this might present.  Suddenly the moment passed and we both finished our business and went on with our day.  One of us nearly left with a wet shoe.

Melamine in Pet Food

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The issue of melamine in pet food has come up again as more lots of pet food are found to be contaminated with it.  At least a few news outlets have published a proposed reason for this contamination by a monomer from another industrial sector.  Melamine is very nitrogen rich- 6 equivalents per mole- so if you spike grain products with it you can cause the nitrogen analysis to read higher than it normally would.  Protein content is one of the factors in the pricing of animal feed, so an additive that would contribute to an uptick in nitrogen content would raise the price or even make a non-saleable lot of feed qualify for sale. 

The nitrogen test that most people think of is the Kjeldahl test.  It is a digestion-distillation-titration method that affords total nitrogen.  This test is still in wide use and is inexpensive to conduct.  A friend who has an Ag Lab still does the test on a bank of burners in his lab for total nitrogen in feed samples.

The practice of adulteration of foodstuffs not limited to China.  As an undergraduate I worked in a dairy processing plant lab and we had to screen for several kinds of mischief.  Dilution of milk with water is an old trick, given that pricing is on a per pound basis, so we had to test each raw milk tanker for total solids content.  We also tested for pH and temperature.

Neutralization of partially fermented raw milk with NaOH was also practiced at one time, so we taste tested each tanker as well since neutralization could not mask off-flavor.  Finally, we had to carefully screen raw milk for residual antibiotics.  Mastitis is an inflamation of the udder and has many causes. One aggravating factor is the common practice of milking ol’ Bessie three times a day.  A sick cow has to be taken off-line to recover. This reduces the productivity of the cow.

Farmers were often tempted to give sick cows a big jolt of antibiotic and get her milking again before the time needed to fully recover and clear the system of antibiotic. This could lead to antibiotic contamination in the tanker.  We performed two tests for penicillin at our plant. The microbiological test we performed was the Bacillus stearothermophilus disk assay. The other was a radiological assay called the Charm test utilizing C-14.  This test could be performed in 20 minutes, whereas the B. stearothermophilus test took 6 hours or so.  The newer Charm tests now take only a few minutes.

Residual antibiotics found in dairy products on the Grocers shelf could put a dairy out of business for repeated infractions. The state health authorities took (take) a dim view of penicillin in milk.

Nanosquat

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Th’ Gaussling is getting an eye-opening introduction to the maddening world high purity products and trace element analysis.  Multiple analytical methods seems to translate to multiple layers of confusion.  I’m a 3-Nines pilgrim in a 4-Nines land of opportunity.  Ya picks yer analytical method and ya stays with it.  Cripes.

It’s an alphabet soup of methods- GDMS, ICPMS, and XRF.  Gonna hafta crack the books again. Watch out. That shadow darkening the library stacks could be cast by a trustee of the f-block.

KSR Int’l v Teleflex, Inc. SCOTUS No. 04-1350

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The authors at Anticipate This! provide a good resource for those of us interested in IP and patents.  They have posted a summary of the recent KSR decision by the US Supreme Court.  If you’ve never read oral argument transcripts from the Supreme court, I would urge the reader to do so.  It’s fascinating.  No matter what you may think of the Supreme Court Justices politically, as a rule they are exceptionally sharp characters. 

We scientists spend very little time with lawyers and judges, other than for the usual public drunkenness or bitter divorce proceedings, so we may not have a calibration point for gauging their scholarly expertise.  Certainly reading transcripts or an actual decision will give the reader insights into who turns the big boat and what the rationale was.

I’m not a legal scholar- I’m more like a NASCAR fan.  I like to watch the legal wreckage go flying through the air and the pit crews scrambling for cover.  In this case, it looks like the USPTO may have to scramble to recalibrate the measure of obviousness.  Hey, pass me a beer …