• 1 Post
  • 914 Comments
Joined 1 year ago
cake
Cake day: June 16th, 2023

help-circle




  • Fun uranium facts: during WWII, one method that the Manhattan Project used to refine uranium (i.e. separate U235 from natural uranium which is mostly non-fissile U238) relied on magnetism. A charged particle moving through a magnetic field experiences a force perpendicular to the direction of motion, which makes it follow a slightly curved path instead of a straight line. This force is the same for both U235 and U238 but since U235 weighs slightly less, its path is slightly more curved. By charging particles of natural uranium and shooting them through a powerful magnetic field, separate collectors can be set up to gather the U235 particles.

    Creating the magnetic field required powerful electromagnets. Normally these would have used copper wire but copper was a valuable strategic metal needed for much of the other military hardware the US was producing, so the Manhattan Project “checked out” the United States’ reserves of silver to build the magnets. For good measure, the electricity for the magnets came mostly from the hydroelectric dams built as part of the Tennessee Valley Authority projects of the 1930s (this is mainly why the Manhattan Project’s uranium processing facilities were located in Oak Ridge). These dams were originally meant to power the production of aluminum, but the US had plenty of other sources for that.
















  • I used to hang with some behavioral psychology grad students (the type that follow the practices of B.F. Skinner and operant conditioning) who were researching the effects of various drugs on pigeons. We were drinking in their lab one time and there were about thirty white pitchers sitting on a table; eventually I noticed that they all had little white, twitching tails sticking out of them - each one contained a pigeon face-down waiting to be put into the testing chamber. I asked them how they managed to get the pigeons into the pitchers and keep them there and they just laughed. They took me into the cage room and showed me how they just opened the cage door and held up a pitcher and the bird would fly like a rocket straight into it. Sometimes they went in so hard they would knock themselves unconscious.

    There are some obvious ethical issues with animal experimentation, but as a certified druggie myself their lives didn’t seem all that bad.