Category Archives: Science

Friday Link-o-Rama

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The Russian cruise missile submarine Kursk went down in the Barents Sea, killing all aboard.  The first link has interesting pictures of the remains of the sub after it had been recovered. The second has interesting background information.

Need a spectrograph for your backyard telescope?  Check out this cool instrument from SBIG.  The good folks at Brookhaven have a table of nuclides online as well as a “Nuclear Wallet Card“. Golly, maybe one day we’ll have electricity too cheap to meter…

Check out the Deep Space Exploration Society- DSES.  They have resurrected a pair of dishes for the purpose of amateur radio astronomy.  They have been doing a sky survey at 1420 MHz.

Looking for something more refractory than the head of Karl Rove?  Check out FiberFrax.

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.

A beautiful day in the neighborhood

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This early May morning was crisp and sunny in our small neighborhood wetland park. Looking west through polarized lenses, the scattered cumulus clouds stood out against an azure blue sky and above fresh snow in the high country. The drone of a Cessna overhead lowered in pitch as the pilot throttled back to decend a bit.  Gonna buzz somebody’s farm from the sound of it.  The fresh layer of snow covers the front and back ranges of the Rockies down to what I’d estimate as the 6000 ft level just a few miles west.  Missed snow by a thousand feet of elevation yesterday.

In the marsh, last seasons cattail stems bounce enthusiastically as red-winged blackbirds jump from stem to stem, pausing for a moment to make their call.  As they sing the long black triangle of their beaks bisect open and a shrill call issues.  As they call their splayed tails drop in unison with the sound, causing the cattail to nod in time with their song. 

These birds are scrappy buggers.  Frequently they join in squabbling groups while in flight to settle some kind of dispute known only to them.  As quickly as it started it is finished and the individuals disperse.

Alberto Gonzales as Jungian Archetype

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For a good essay on the Alberto Gonzales mess, see The Smirking Chimp.  Th’ Gaussling has been searching for a Jungian archetype representing people who are “never in doubt, but frequently wrong”.  Maybe Gonzo is the man. 

There have been many possible nominees in the Bush II administration- POTUS, Cheney, Wolfowitz, Rumsfeld, etc. But Gonzo seems to be the most tragic of the lot.

Note to future generations: I was going to further criticize POTUS, but given that he is sure to be savaged by historians, I’ll just stand clear and let experts have at it.

Dammit. The three horses I bet on in the Kentucky Derby all lost.

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.

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.

“Riding Rockets”- A Review

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I just finished reading Mike Mullane’s autobiographic “Riding Rockets“.  Mullane is a retired mission specialist astronaut with 3 missions under his belt.  It turns out that Mullane and I share one discouraging life experience.  I also wanted to be an astronaut and was also disappointed to learn in college (Air Force ROTC) that my nearsightedness would prevent me from getting a pilot slot in the Air Force or Navy.  Undaunted, Mullane went on to the next best option of GIB (Guy In Back) and became a USAF weapon systems officer.  His transition to astronaut from GIB was made possible by the NASA’s decision to eliminate the requirement of pilot experience as a prerequisite for mission specialist .  No doubt his degree from West Point, 150 combat missions in Viet Nam, test pilot school at Edwards, and a masters in aeronautical engineering helped him a bit.  I realized that I was a nearsighted, pathological smartass and left ROTC and went into chemistry.  Mullane persisted and got into space. I succumbed to the enchantment of organic chemistry and explored conformational space.

Mullane writes rather well and provides a reasonably balanced narrative over the time spanning his career. I would say that the main reason to read the book would be to get some insight into life in the astronaut corps.   If you put two people in a room, you have politics.  And it is no different with astronauts. Mullane details what can only be described as a byzantine system of decision-making for mission assignments and the characters who made these decisions.

Mullane describes in considerable detail the experience of a scrubbed launch. He bid farewell to his family and strapped a fully fueled shuttle to his backside 9 times for 3 launches.  Mullane tells of his own private fears and the fear that was (is) felt among many other astronauts- a feeling quite apart from the confident and laconic persona they might show in public. Indeed, he has been outspoken in regard to the safety of the shuttle fleet and in a manner uncharacteristic of astronauts, generally.

Far from being a monolithic group of superheros, the astronaut corp consists of a surprisingly diverse group of individuals.  As a group, astronauts are super achievers and not lacking the usual spectrum of attributes you might expect.  There is no shortage of ego or swaggering bravado.   Historically, astronauts come from an aeronautical background and as such, are accustomed to the flight environment and the norms that go along with it. During Mullanes tenure at NASA, the program saw civilian and other non-traditional astronauts take increasingly important roles in the mission.  In particular, this period of time following the first trial flights saw female astronauts accumulating a considerable number flight hours on orbit.

He describes in detail how the astronauts felt after the loss of Challenger and Columbia.  Mullane is of the opinion that the shuttle should have a better crew escape system.  Evidently he logged an ejection from an F-111, so he has first hand experience with bailout systems. There are literally thousands of parts and systems whose failure could tragically end a mission and the lives of its crew.  But like everyone who wants to fly in space, you swallow your fears and strap in anyway.

In the context of books in this genre, I’d give him a A- for his courage to be critical of NASA.  He now works as a motivational speaker.

Mixing and Unmixing

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Today was take-your-kid-to-work-day.  In honor of this we put on a chemistry show in one of the labs.  Burned some Mg ribbon, shrunk some balloons in LN2, blew up some balloons with dry ice, reduced iodine with ascorbic acid, and we unmixed some NaCl and carbon black. 

One of the barriers to teaching chemistry is a level of physical abstraction that is hard to get around.  It is hard to get around trivial explanations when the audience is not ready to discuss electrons.  Many of the really insightful concepts in chemistry are inherently abstract and age inappropriate for the younger crowd, so to compensate, chemistry demonstrations are often heavy in the whizbang components.  That’s fine.  It should be fun and visually appealing, especially for K-6. 

I like to do mixing and unmixing because it demonstrates something about materials handling.  It also represents an activity that occupies much of our time.  Separation science is not commonly called “unmixing”, but for chemistry demonstrations it causes kids to ponder the problem for a bit.  They all have experience in mixing things- we talk about that.  Then I ask the question “What if I asked you to unmix that KoolAid”?  A few of the more worldly ones might suggest boiling off the water.  But most kids seem to be stumped- they will admit that they would have never considered the possibility of unmixing. 

So we dissolve some NaCl in water and make a solution.  The use of a magnetic stirrer and stirbar makes way for a minor diversion with magnets and iron filings. Then we blend in a bit of carbon black. Using a Buchner Filter, filter paper, and Celite, we do the vacuum filtration, showing the remains of the carbon in the Celite.  The filtrate is then treated with some “Anti-Solvent” like acetone and the salt comes crashing out. 

Yeah, I know. It is pretty tame.  But it can be done cheaply in 45 minutes and the kids can see their parents actually doing something. 

Jane Goodall

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Went to a public lecture by Jane Goodall last night. The arena was packed.  She and members of her institute have found a type of formula for combining conservation and economic growth.  At some point she realized that you can’t sell conservation in a vacuum.  People who live near fragile preserves like Gombe have to make a living.  They need food and firewood. 

Human population pressures also threaten the shrinking wildlife preserves all over the world and in Africa in particular. One way to encourage lower population growth is to look after public health and, in particular, the welfare of women. They’ve noticed that families naturally tend to have fewer babies when infant mortality rates lower. Lower mortality rates can be achieved through the application of very fundamental improvements in hygiene and health care.

One of the critical approaches they are taking in Africa is to improve the life of women through micro loans.  This has proven effective in many other parts of the world and Goodall reports it is having a beneficial effect in Africa as well.

As I sat and listened to the lecture, I was overcome with the futility of our ever increasing consumerism.  Take our collective response to the increasing scarcity of petroleum.   The big ideas seem to involve finding new ways to sustain high consumption- e.g., the replacement of petroleum with ethanol or hydrogen.  The idea that we might have to throttle back our per capita consumption of stuff extracted from the ground is ignored.

Well, of course the national stage isn’t filled with people promoting reduced consumption.  There is no money in reducing demand. Who wants to hear that? 

Minimally, the USA must go the way of Europe in terms of lower average consumption.  Higher population density combined with higher priced energy will lead to more modest consumption of goods due to lifestyles adjusting to scarcity. 

Bush II. Sphericated or Flaticular?

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Here along the front range of the Rocky Mountains we have a few alternative newspapers available- you know, the kind not owned by Rupert Murdoch. They tend to be a bit Bohemian and consequently are shunned by righteous Dittoheads. Other parts of the country have them as well- college towns mostly. They cater to those of us who aren’t afraid to be known as liberals.  These papers run a syndicated cartoon called This Modern World by a guy known as Tom Tomorrow. 

Because of copyright issues, I’ll have to link to the site rather than paste an image.