Posted in Education, Physical Chemistry, Science Education, Spectroscopy

What is pchem?

Pchem is short for Physical Chemistry. It is hated by all. It is SO bad (the audience asks, “How bad is it?”), that it has it’s own bumper sticker!
p-chem
Why is pchem so mistreated?
Like a scientific tax accountant, a P-chemist worries about the energetic balance sheet, the gains and losses of energy, the ratio of usable to unusable energy. We pull the thread through all states of matter – liquid, solid, gas, plasma, elastic, plastic, glass, etc.
My favorite subsection of pchem is symmetry and spectroscopy. Spectroscopy is the study of light interacting with matter. And symmetry is used to decipher these interactions. There is no better example of the mathematical beauty of our universe than the unexpected explanatory power of group theory as it applies to absorption and emission of light.
Fireworks, hair dye, crayons, ink, glow sticks, lightning bugs, and all the rest can be understood through pchem – specifically my field of spectroscopy.
There is much more to pchem. If you have made it this far, then you are truly curious. Therefore, I give you the table of contents to a typical pchem textbook. (You will have to “Look Inside” at the Amazon site to view the TOC.)
And, I ask you to share and subscribe to this blog. Comment below with suggestions for posts.
Posted in Science Education

Failure is Your Friend

“Mother Nature is a tough old bird” my undergraduate research advisor Dr Joe Lagowski was fond of saying. The only way to find the limits of nature is to try experiments that fail.

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Sometimes it is the technology that fails. We recently purchased a 3D printer so we can print new measurement devices developed in our lab. As the failures mount and our recycled ABS plastic bin fills we are learning the precision limits of our Makerbot and ABS filament.

Sometimes it’s the people who fail. As we work through the patent process we find that some do not share our passion for the product of our efforts. Motivations vary, but we press on to the goal because to do otherwise would be worse than failure.

But on some rare occasions an actual limit of nature is found. These are the victories in failure. When the technological tools are working well and the people are qualified and alert a verified failure is a great result. To quote Lagowski once more, “No is an answer, too.”

Have you ever had a Successful Failure in science? Comment on it.

Posted in Education, Spectroscopy, UV-VIS-NIR

What makes a rainbow?

All of us love a rainbow, and a double rainbow is even more exciting. This is pchem* in action!

350px-Double-Rainbow
A double rainbow photographed in Karlsruhe on July 22, 2011. Leonardo Weiss http://commons.wikimedia.org/wiki/File:Double-Rainbow.jpg

You may have noticed that rainbows only appear with the sun at your back. Why?

Rainbows are angle-dependent. The light coming from behind you hits water drops of a particular size and at a particular angle so that they are diffracted (bent) inside the drop. This can occur in a clockwise or counter clockwise manner. The clockwise path through the drop to your eye and the counter-clockwise path occur at slightly different angles. This creates the two rainbows.

The different wavelengths of light from red to blue also travel at slightly different angles (just like through a prism), and this creates the spread of colors in each rainbow.

Have you ever seen a triple or higher-numbered set of rainbows?

Some will brag and say they have. But this is extremely improbable. If their eyes were sensitive enough to see this higher-order diffraction, then they would be blinded by the bright sunlight needed to produce the rainbow in the first place. The probability of light traveling multiple circles within the water drops to create second- (and higher-) order diffraction effects is very slim compared to the single pass rainbows that we are all familiar with.

Post links to your favorite rainbow images in the comment section.

Subscribe to this blog for more Pchem* topics.

*Pchem (Physical Chemistry) is the study of the physical properties of the universe.

Posted in Contact Angle, D L Williams, FTIR, Hansen Solubility Parameters, Physical Chemistry, Raman, Solubility, Solvent Blending, Spectroscopy, UV-VIS-NIR, XPS

Corporate Research Funding in Uncertain Times

Some points that describe the current R&D funding climate:

  • Continued uncertainty in corporate R&D hiring
    US non-financial corporate cash holdings rose to $1.24 trillion at the end of 2011 according to Moody’s. One reason among many is a reluctance to hire until the uncertainty surrounding benefits costs is reduced.
  • Tightening of government funding of university R&D
    The US government still funds a significant amount of chemical research, but competition for those funds is increasing greatly. The growing deficit must eventually have an impact on the availability of funds for chemical research.

As a physical chemist, I am partial to APPLIED chemistry research, and the interactions I have had with corporations and government contractors have been enjoyable and fruitful for both parties.

I have prepared this blog post and my new “Sponsors Page” on my university website to actively address the R&D needs of corporations and government contractors.  Many of these entities are under a hiring freeze, and yet, their chemistry-related problems continue unaddressed.

When I worked for a government contractor, I dealt with these issues:

  • “I could solve this problem in 6 months, if I didn’t have to support production, also.”
  • “I’d love to hire someone to research this and other issues but
    1) we are under a hiring freeze,
    2) we don’t have the budget for a whole person (1.0 FTE),
    3) we can afford the salary but are reluctant to commit to an unknown fringe benefit committment,
    4) we can afford a science temp, but we need a Ph.D. chemist.”
  • “Maybe a university researcher could help, but there’s no telling what an Ivory Tower Pinhead is going to spend our money on.  And, what would we have to show for it?”

To quote a recent President, “I feel your pain.”  But not all residents of the Ivory Tower are Pinheads.  Here are the benefits of funding an APPLIED-SCIENCE-MINDED university professor and his students to address your problem.

  • Academic salaries for Ph.D. chemists ($70k, 2012 median) are 65% of that in Industry ($107k, 2012 median) according to the ACS Employment Survey, so renting a brain is potentially cheaper than buying one.  Often these are 9-month salaries, but this annualizes to $93k, which is $14k less than the industry median 12-month salary.
  • Academic chemists are able to spend 100% of their effort on your problem during the summer months.  If the median salary of $70k is for 9-months, then funding this scientist for three full months in the summer is only $23k.  Universities tack on varying amounts of overhead and fringe benefits costs to this number so the actual costs will be more like $40k ($85 / hr all-inclusive).  This is still a very reasonable amount for 3-months of a PhD chemist’s time.
  • Academic institutions have an amazing array of instrumentation that your company could not justify purchasing.  The overhead costs tacked onto the academic chemist’s labor rate is the price of admission to the instrumentation lab or computational facility.  Our lab charges consumables costs on a per-day or per-sample basis in the range of $20.  This may seem to add up, but so do the costs of solvents, vials, etc.
  • Academic institutions are FULL of eager chemistry majors who LOVE to study research problems that are “real life”.  These students are also inexpensive when compared to hourly chemical technicians.  A typical student will have a fully-burdened (with overhead) rate of $20 per hour all-inclusive.  These students will graduate with a working knowlege of your industry and will be excellent prospects for future hires.

The number-one factor to consider is the principal investigator (PI).  Does he or she understand your problem?  Have they done similar work in the past?  I have turned down funding because I did not think I could deliver value to the sponsor.  Find someone who understands your terms, your culture, your requirements, and the practical aspects of implementing the ideas proposed.

If your interests are in any of these areas, I’d love for you to contact me.

  • Cleanliness verification, contact angle measurements, coupon tests
  • Solvent properties, surface tension and hydrostatic densities, Hansen solubility parameters vs Hildebrand solubility parameters
  • Solvent blending, solvent blend prediction, miscibility
  • Solvent substitution, reduction of hazards, reactivity, ozone depletion potential, or global warming potential
  • Material compatibility, polymer stress cracking, polymer swell, polymer processing solvents
  • Recrystallization and crystal morphology control based upon non-solvent interactions
  • High-explosive detection, solubility, modeling, spectroscopy, recrystallization, precipitation, and PBX production/processing
  • Spectral assignments and predictions (FTIR, Raman, UVVIS, XPS)
  • Computational chemistry, ab initio, density functional theory, quantitative structure property relationships (QSPR/QSAR)
  • Six-Sigma Blackbelt – consulting services

There are ways to continue innovating in the current business climate.  I’d love to help if I can.

-Darren

Posted in Education

The #WAR on Cramming

Homework serves several purposes in academic pursuits.  It guides the students through a subset of material the professor deems important. It forshadows the examination. It serves as a scaffold for the student to assist the building of their body of knowledge in the topic.

It should not be “busy work” because this wastes valuable student time.  It should not create a protracted grading burden on the professor, because immediate feedback is best for the student when learning new material.

Therefore, I am exploring the following with positive initial results.  I use multiple choice homework problems, because these are automatically graded online by the Blackboard learning system.  These assignments fullfil the purposes of forshadowing the exam, and guide the student through the appropriate material.

The negative aspect of this is the natural focus of the student on “which letter is the correct answer”.  I do NOT care about which letter they check.  I want them struggling with the problems, building their body of knowledge, and internalizing the concepts and theories.

Therefore, I have changed the grading rubric to punish simply getting the correct letters in one setting.  The only way to achieve a perfect score on the homework is to do the following:

1. Take the homework exam multiple times over several days showing improvement towards the eventual score of 100%.

One can EASILY fake this, which is why it will only be 5 to 10% of the weighted average of a given course.  But instead of faking this apparent activity, consider actively using the process that I am encouraging.

So to my students, I give the following advice:

  • As soon as the homework test is made available, log in and take it cold.  Give your best guess on the vocabulary.  Estimate the numerical answers.  Do your best to ace the test “cold” without knowing the material.
  • Then, download the pdf version of the homework test. Over the next few days, work the problems in your “problems composition book” (hint, make one of these).  Work similar problems from the back of the text.  Work similar problems from the Internet.  Evaluate why the right answers are right.
  • Log back into Blackboard.  Take the homework test again.  If you do not make 100%, then work the ones that confuse you.  Ask about them in class.  Get with your study group.  If you are convinced your answers are right, perhaps there is an error in the homework test.  Ask about it in class.
  • Finally, you should be able to achieve a 100% on the homework test, AND THE RECORD OF YOUR MULTIPLE TESTS ON BLACKBOARD will be evidence that you deserve a 100% for PARTICIPATING in the homework assignment.

I welcome your constructive input.

Posted in D L Williams, Education, Physical Chemistry

Potential Source of the Fukushima Daiichi 1 Explosion

Here is my personal analysis of the Fukushima Daiichi 1 explosion that occurred March 12, 2011. It is possible that the cooling water level in the spent fuel storage pool dropped enough to expose the fuel elements. This could generate hydrogen gas, and is a potential source of the explosion. Hat tip to the Nuclear Energy Institute for providing an image of the reactor design and secondary containment area.

I have created a Prezi to walk you through my thoughts.

I welcome your thoughts in the comments area.

Thanks for watching, and keep praying for the Japanese people as they continue to battle the after effects of this earthquake.

Posted in D L Williams, Education, Physical Chemistry

This Week in Pchem – Energy Minimization Techniques

This week in pchem we are discussing the energy minimization techniques that are used in computational chemistry. The students will build a mock energy function that models the dihedral rotation of 1,2-dichloroethane. Then three methods (The Monte Carlo Method, Newton minimization, and Metropolis simulated annealing) will be employed to solve for the preferred (lowest energy) dihedral angle (a).   

A performance plot will also be generated that shows the lowest energy and its root mean squared deviation RMSD from the known minimum structure (a = 180 degrees).  This plot clearly shows Newton’s propensity to get stuck in local minima.  It also clearly shows that the Monte Carlo method will always find the global minimum, but with increasing inefficiency.  And finally, the Metropolis simulated annealing technique is found to be flexible enough to accurately locate the minimum energy structure every time provided that the step size and temperatures are “tuned”. 

Stay “tuned” for a planned video of the spreadsheet in action.

You can participate!  Download the Rosetta@home screen saver, and solve protein folding problems in your sleep.  (I have no official connection to the Rosetta at home folks, but their work is great! http://boinc.bakerlab.org/rosetta/)