Heat and Light

Benoît Paul Émile Clapeyron, 19^th century French Engineer and Physicist is generally credited with developing what we know to be the 2^nd law of thermodynamics, and his work has allowed us to evaluate the upper limit of efficiency in an internal combustion engine (hint: combustion engines are not particularly efficient).  But, to my knowledge, there is no historical record of him ever baking a Madeleine cake so, well, he can’t have been all that great.

There’s been quite a lot of fuss about light bulbs lately.  Some people don’t like the new, energy efficient ones because they look weird and take longer to illuminate to full brightness.  It is true that it can be little tricky to attach a lamp shade to the new design (but do we really think this is an unsolvable problem?  Really?), and the new ones don’t generate enough heat to drive an Easy-Bake oven but they do two things well: light up a room and use less energy when they do so.  The shape is actually necessary because, unlike an incandescent bulb where the light emanates from a white-hot filament (typically tungsten; thorium, a radioactive isotope is often produced during the fabrication of tungsten filaments – oops!), the new bulbs generate light at the surface of the bulb only and you get more light out when the surface area is higher – which it is in the curly shape.  But there’s a little more to it than that.  The bulb is really a twisted fluorescent lamp in which UV light from excited gas atoms inside the tube excites a fluorescent compound painted onto the surface of the bulb.  In fluorescence, typically higher energy light goes in (in this case UV) and lower energy light comes out (in this case visible/white light).  It sounds weird that you put in one kind of light to get another kind but you can see lots of examples – black lights, which emit ultraviolet light, will cause fluorescent paints to “glow” in the dark (next time you’re in a disco, make sure that you brush your teeth and wear something brightly colored – it will be dark, but you’ll see what I’m talking about.).

We need both, sure, but there’s a time for each.  Light informs, illuminates, opens the doors and reveals the details for all to see.  Heat, not so much.

Less heat.  More light.  Please.  The good news is that reasonable people seem to be leaving the drama to Broadway, and Glee (here is a recent NY Times story on the subject).

Where are the science experts?

When you have questions about health and science, some people go to the internet while others, like my brother-in-law, call me.  I used to think he wanted to know the answers to the questions (what are stem cells and why are they important?) but, lately, I have been thinking that he wants to keep me from getting bored during the holidays.  Am I dull?  Really?  Save that thought…

What happens when the President or the Congress have questions about science?  I mean, surely they have must have questions.  Don’t get me wrong, President Obama (B.A. Columbia University, J.D. Harvard University) is pretty bright and a number congressmen and women have advanced degrees but do they know about the way the ozone hole works?  Or what the differences are between adult and embryonic stem cells.  What do they know about climate change, or greenhouse gases?  Do they know why CO₂ is a greenhouse gas and why N₂ is not?  Are they scared of bisphenol A?  Where do they go for help?  What about judges who are often asked to evaluate arguments of a scientific nature (do breast implants adversely affect human health?).

Established by President Lincoln in 1963, the U.S. National Academies today includes the National Academy of Sciences (or just NAS) the Institute of Medicine (IOM), the National Academy of Engineering (NAE), and the National Research Council (NRC).  The legislation introduced by Senator Henry Wilson of Massachusetts set forth – in my opinion sensibly - the following principles:

[T]he Academy shall, whenever called upon by any department of the Government, investigate, examine, experiment, and report upon any subject of science or art, the actual expense of such investigations, examinations, experiments, and reports to be paid from appropriations which may be made for the purpose, but the Academy shall receive no compensation whatever for any services to the Government of the United States.

—An Act to Incorporate the National Academy of Sciences (NAS)  

Initially, the academy was stocked, kind of like a trout pond, with 50 members and, later, members (like Spencer Baird, American icthyologist) were added by a nomination and election of current members.  Today, about 2,000 scientists, doctors, and engineers are members of this elite institution.  How elite?  About 200 Nobel prizes have been awarded to Academy members.  Membership doesn’t pave the way for a Nobel Prize any more than winning a Screen Actors Guild award leads to an Oscar.  Both the Nobel committee and the Academy are looking for the brightest minds to help advise the World, the President and the Congress to help them solve the big problems of our time.  In 1916, when the National Research Council (NRC) was added, that “problem,” for which the nations needs were greater than the NAS and NAE (established in 1864) could accommodate, was the [first] World War.  

I love going to the National Academy of Science web site (www.nas.edu) and looking at reports that address issues of research in biotechnology, medicine, education, and natural resources.  While somewhat longer than the brief snippets that get out to the popular press, many are written in very accessible language. There are 600 “projects” under investigation today, spanning Agriculture (Sustainable Development of Algal Biofuels) to Biodiversity (A to B?).  In the area of nuclear security, the U.S. Department of Homeland Security (DHS) wanted to use new radiation detectors to screen cargo containers for nuclear/radiological material at US ports and border crossings, so Congress told DHS to ask the NRC to advise them on testing, analysis, costs, and benefits.  One neat side effect is that the results of all these Congressional “homework assignments” is a report that you can buy (for the bound copy) or download for… wait for it… free!

The NAS, NAE, and IOM also publishes (along with the University of Texas at Dallas) a monthly magazine Issues in Science and Technology that you can read online.

Don’t like reports?  Magazines?  The National Academies feel your pain.  They’ve also got lots of informative booklets (most of which can be downloaded for free) on a number of critically important topics like:

What You Need to Know About Energy

Understanding and Responding to Climate Change

Understanding Stem Cells: An Overview of the Science and Issues from the National Academies 

Understanding Our Microbial Planet: The New Science of Metagenomics 

The Science of Restoring the Everglades

Critical Issues in Transportation 

Drinking Water: Understanding the Science and Policy Behind a Critical Resource 

New Horizons in Plant Sciences

More information on publications of the National Academies can be found at http://www.nationalacademies.org/publications/

The legislature and the President had the wisdom to establish the National Academies.  They knew that the problems facing the nation were too big and complex for legislators to solve them alone, and in one sweeping step, they harnessed the energy of the best and brightest minds to study, explain, and help us to tackle them.  


Update: The FBI asked the NAS to evaluate their scientific investigation of the anthrax letters from 2001. In their report, which was peer-reviewed - a critical step in good science - before its release on February 15th, the NAS commended the FBI for drawing on the expertise of government and private-sector in building a novel Anthrax repository but suggested that recently-developed techniques could have increased the strength of their conclusions.  I have oversimplified the extensive investigation that the NAS conducted.  For more information on this, check out the report.

George Washington was a microbiologist

True story.  I am completely not making this up.

George Washington, commander of the revolutionary army and the first President of the United States, performed some of the earliest documented experiments in microbiology, when he and a team of collaborators, including Thomas Paine, paddled out into the Millstone River in central New Jersey to perform an experiment.  Paine, who wrote Common Sense, went to see General Washington with a letter of introduction from Ben Franklin who had hoped to secure a pension from the US Congress for Mr. Paine.  For inspiration, Washington had selections from Paine's writings read aloud to his troops each night in the hopes that it would inspire them during the war.  At any rate, Paine had heard that there were sections of the river that could be set on fire so, one night, he, Washington and some troops paddled out into the river. As Paine wrote of the incident in a letter on November 5th of 1783:

We had several times been told that the [Millstone] river… might be set on fire… When the mud at the bottom was disturbed by poles, the air bubbles rose fast, and I saw the fire take from General Washington’s light and descend to the surface of the water... This was demonstrative evidence that what was called setting the river on fire was setting on fire the inflammable air that arose out of the mud.

But Washington wasn't alone in these early experiments.  At approximately the same time, Allesandro Volta, the Italian scientist for whom the term volt is named, wrote to Father Carlo Campi in November 1776 (7 years before the Washington-Paine experiment) of conducting similar experiments on Lake Maggiore in the Italian Alps:

So, on the 3rd of this month, with my head full of such ideas, and being in a little boat on Lake Maggiore, and passing close to an area covered with reeds, I started to poke and stir the bottom with my cane.  So much air emerged that I decided to collect a quantity in a large glass container… This air burns with a beautiful blue flame.

The “flammable gas” referred to in these experiments was “swamp gas,” of which a large component is methane, a little molecule in which one carbon is bonded to four hydrogens.  Chemical formula: CH₄.

You may wonder where the "microbiology" comes in.  Here's how:

There are a group of microscopic organisms that derive chemical energy from the conversion of carbon in a variety of sources into methane.  These methanogens (“methane making”) are not classified as bacteria but, rather, come from a separate kingdom, Archaea, which derives from the Greek word 'arcaia' which means “ancient things” (archaic has the same root). Typically, methanogens live in mud on the bottoms of relatively quiet rivers and ponds.  You don’t have to do anything to get them to grow except create conditions in which they can flourish.  Typically that means (a) remove the oxygen (these environments are called “anoxic”) and (b) provide a nice source of carbon, usually in the form of decaying organic matter (tree leaves, for instance).  Other natural sources include carbon dioxide, methanol, acetic acid (among others), and halocarbons (there is some evidence that methanogens can help to detoxify chemical wastes, so this chemistry has implications beyond historical interest).

Did Paine know about Volta's experiments?  Seems unlikely, but it’s interesting to note that, over a century before quantum mechanics, citizen-farmer-statesmen-scientists were studying the natural world to understand the how and why.  They may not have known about atoms, molecules, or the scientific method as practiced in the 21st century but, like any good scientist, they each designed an experiment that tested a hypothesis, collected their data, and analyzed their results.

Incidentally, methane is produced in landfills, by termites, and the rumens of cows – all regions where methanogens are allowed to flourish – and it is produced in enormous quantities.  Some estimates suggest that a billion tons of methane are released into the atmosphere annually where some of it is oxidized back to carbon dioxide and absorbed during plant metabolism, but it’s influence doesn’t stop there.  Methane is an important greenhouse gas.  It isn’t present to as great an extent as CO₂, but it has a higher heat capacity than carbon dioxide.