Stuff happening

The HUG lab has been busy all week.

The V1.3 cells in differential mode are waiting for a nice isothermal box to shield it from Ambient temperature differences that may have been creating falsely positive data.  The new boxes are fabricated and the controls and instrumentation are being put in place.  Then we will test them and see how well they hold a constant temperature inside.

The Helmholtz coils will be incorporated around the V 1.3 cells once the cells are in these boxes. That's the only way to know that we are seeing meaningful temperature differences.

The Multiwire test is at the top of the calibrated range on input power and running at very near the top of the intended temperature in the cell.  And it is just starting, at that temeprature (450+ C) to show a possibly meaningful excess power reading that seems to be increasing exponentially with the temperature.  We tried putting a water jacket around the outer shell to help cool it and allow it to run at higher temperatures, but our water bath was room temp and didn't enhance the cooling at all.  Cooling the water down to 15C does not seem to helping either.  We possibly need to get the wire up over 500, which in the glass cells with direct heating can happen easily.  

Meanwhile, Paul and Wes have been tuning up the three slightly different versions of the vacuum bottle calorimeters.  The third version totally enclosed in a 2 inch thick foam jacket is definitely the most stable.  

The job largely consists of tuning PID controls and testing the thermal response to minimize the control noise under different conditions.  Sometimes it isn't terribly straightforward.

On Thursday, a group of us went to visit St Cloud State University, which is the closest major university to us.  There is a theoretical physicist we chatted with and wonderful, integrated science and engineering facility that we toured.  They have the closest SEM to our location and it has a working EDS.  Hopefully we will be able to take advantage of it, now that we know it is there.

And, finally, a new experiment to rule out the Langmuir effect as a possible explanation for the higher temperature on the glass has caught out attention.  We will post more on that soon.