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Cake day: June 16th, 2023

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  • 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 grew up in a town in Ohio where the famous abolitionist John Brown (hanged in 1859 after his abortive raid on Harpers Ferry) had built a tannery in the 1840s 1835 that was still standing in 1976. To celebrate the bicentennial, the city council had it condemned and torn down, to make way for … a parking lot. Hilariously, the council claimed it was a danger because it was about to collapse, but it took three days to demolish and they had to bring in special heavy equipment to do it after their wrecking balls failed to make a dent in it. This thing had been built with massive 40-foot long oak beams with 12"x8" cross-sections that showed no signs of rot (my dad salvaged a piece of one of these beams and set it up as a bench in our garden, and it was still in good shape in 2012 despite being outside the whole time), so it could have easily been preserved as a historical site. In fact it had been declared an official historical site by the state just days before its destruction but the town council simply ignored that.

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  • I wish police would simply enforce noise ordinances

    I live next to a catholic church/school and sometimes on the weekend or near sunset a local kid rides his motocross bike all around the church yard. Annoying as fuck and it chews up the yard and everything. I’ve called the cops three or four times but they’ve never bothered to send an officer out. I called the church and all they did was install a bunch of super-bright LED lights which are on 24 hours a day. Kid still rides his bike there and now I can’t sit outside at night anymore because of the fucking lights.









  • OTOH it’s absolutely insane what new bicycles are costing these days - bikes can be money pits too. I bought my road bike 12 years ago for about $1800 and was kicking myself for years for spending that much. A modern road bike (with disc brakes, wi-fi controlled electronic shifters etc.) would be in the neighborhood of ten grand, more than my car cost. Meanwhile my favorite bike is the 25yo hybrid that I bought on Craigslist for $100.