Monday, July 27, 2015

The "Good One" Club

Special Summer Series: Elizabeth Hoover de Galvez from the library's reference department, shares her observations of summer research at Coe. This summer she is working with Dr. Feller's materials science group.
It is inevitable that in a teaching lab, mistakes happen.  Students (and sometimes faculty) shatter, overheat, mislabel, and otherwise mess up.  As I started learning about the equipment in the physics lab, I sometimes felt paralyzed by all that could go wrong.  The way that the physics students handle these errors is with humor--by writing up a satirical account of the misdeed and posting in the halls of Peterson for all to see.  Then everyone can laugh about (and learn from) their mistakes together.    

Recent "good ones" (many of these may not be official "good ones" which get written up, but are just a few mistakes which have happened on the days I've been in the physics labs):

  • a sample of glass was mailed off to another university; the researchers started getting unexpected results in their tests.  It was finally discovered that the students who had made, packaged, and sent the samples had mislabeled one of them.
  • the scanning electron microscope was used to examine a sample which looked very strange under high-magnification.  After much head-scratching, it was discovered that the actual sample had been blown off of the viewing slide leaving only a highly magnified image of a piece of tape
  • the small enclosed furnace room reeked of ammonia after students heated a glass which contained (I believe) ammonium powder of some form
  • someone used highly flammable acetone cleaning solution in the furnace room
  • while working with hydrochloric acid to clean crucibles, a student left the water running alongside an uncapped bottle of acid.  The students that arrived later found a puddle which they had to verify wasn't acid before cleaning up.
  • the students also mentioned a couple of past accidents--melted platinum crucibles worth hundreds of dollars and equipment accidentally frozen by liquid nitrogen.   
When I first heard about the good one club, I was slightly uncomfortable with the idea; I am a fairly empathetic person and have been known to suffer from vicarious embarrassment.  But since learning that it is a somewhat formal/organized activity with support from faculty, I've decided that I'd prefer to have my mistakes broadcast openly with humor rather than whispered about.

Monday, July 6, 2015

Tellurium Glass--to England via Coe

Special Summer Series: Elizabeth Hoover de Galvez from the library's reference department, shares her observations of summer research at Coe. This summer she is working with Dr. Feller's materials science group.
At her poster session in the spring of 2015, Brittany Hauke told me that she had worked the previous summer to make a mere 2-3 grams of  tellurium glass.  She explained the baffling reasons behind the difficulty of making the glass.

The first meeting I attended with the materials science working group, Dr. Feller praised Brittany's accomplishment, saying that making this glass was extremely frustrating and required "surgeon's hands".

Over the last couple of weeks, I got to see Brittany and her lab partner Ariel Crego make and test several samples of the glass.  After two cycles of heating, roller quenching, and "mining" for pieces of glass, this was the glass they had managed to make:
Ariel Crego displays two vials of tellurium glass.  The glass on the right
turned yellow for an unknown reason, but it otherwise tested correctly. 
And here's a few steps in the process of making the glass:

First various powdered chemicals are mixed up according to precise calculations based on chemical weight.  They are melted together, reweighed to measure loss due to escaping gasses, and then reheated.  Finally, the molten glass is poured over the roller quencher, a piece of equipment which was invented right here at Coe.  The roller quencher cools the glass much more quickly than other methods.

In the videos first a run through the roller quenching, followed by

Brittany putting the molten glass in for a run through the roller quencher.

 The tedious process of picking through the flakes of crystal for any shards of glass.  I couldn't really see the difference, but apparently the crystal is more white.  Once the glass is out, they melt the crystal back down and run it through the roller quencher again.

They may reheat and run the same material through the roller quencher 4 or more times. 

Right now, Brittany is at the University of Nottingham in England working with researchers to do further testing on the glass.  One possible application for the glass may be in fiber optics.