sey085

Lately, things at work have not been going particularly well. My main project (since my arrival) has been to build a set of gradient coils which are the basis of a magnetic resonance microscope. My problem, of late, has been that for reasons unknown to me, my gradient coils have developed a nasty habit of killing themselves in the middle of a measurement. What does a dead gradient coil look like? Here's an early kill of mine: Fig. 1: A destroyed coil. The red lines are wires which carry very large currents (up to 100 A) but for only very short times (no longer than one millisecond). The Aluminum frame transports the heat away from the wires and is connected to a water cooling system. Notice the dark charring, the melted plastic, and the overall ugliness of the situation. When something like this happens, I have to scrape out all the bad stuff, replace everything and start over. It is a time-consuming and boring process and one at which I have become far too skilled. With ...

I'm sure this will come as somewhat of a shock to my regular readers, but curiously enough, I actually manage to get some work done here in Switzerland, every so often. Today was one of those days. As some of you have probably heard, the project I'm working on here is a micro-MRI system. Basically, we want to take microscopic MRI's of interesting chemical or biological samples. My job was to build the "gradient" imaging system which is responsible for making the "pictures" -- if you've ever been in an MRI, you'll also recognize it as the thing making the horrible, loud noises that you hear. Although there have been a lot of ups and downs -- mainly downs -- I finally have the prototype system up and mostly working. Last night I took an image, and this morning I did some very, very basic analysis of the data. Here is the result: Fig. 1: MRI image of PDMS sample. The x and y scales are in microns (0.001 mm), thus the total range of the image...