Recent comments in /f/askscience

loggic t1_j1bsvk0 wrote

Reply to comment by lo53n in How do fusion scientists expect to produce enough Tritium to sustain D-T fusion (see text)? by DanTheTerrible

Thermoelectric devices are getting more efficient every day. This one achieved greater than 40% thermal efficiency. Of course, that was when the hot end was 2400 C, (very nearly the boiling temperature of aluminum) so there's still some work to be done to make them a bit more practical.

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cdstephens t1_j1bq2qw wrote

Reply to comment by graebot in How do fusion scientists expect to produce enough Tritium to sustain D-T fusion (see text)? by DanTheTerrible

No, fusion devices cannot lead to an uncontrolled chain reaction. The reason is because the plasma needs to be confined in order to maintain the appropriate density and temperature; the Sun uses gravity to confine the plasma. In contrast, if the magnetic fields were turned off in a magnetic fusion device, the fusion plasma would just expand outwards into the wall and then cool down.

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FinndBors t1_j1bq2hs wrote

Reply to comment by lo53n in How do fusion scientists expect to produce enough Tritium to sustain D-T fusion (see text)? by DanTheTerrible

You are looking for aneutronic fusion: https://en.wikipedia.org/wiki/Aneutronic_fusion

He3 is required but rare, or Boron fusion but needs a ton more input energy than D-T fusion. The sibling comments regarding Helion Energy is an attempt to do this using He3 and a way to synthesize it since it is very rare. The way they synthesize it is D-D fusion which does produce neutrons.

Regarding He3, people talk about mining this on the moon since it is less rare there, but IMO, its a stupid idea since it isn't like mining an ore where there is concentrations of it, it's weakly spread out all over the surface.

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thedelusionalwriter t1_j1bpoql wrote

Reply to How long does it take to get antibodies after recovering from Omicron? by Asleep_Sandwich5963

You recover because of antibodies - they block the virus from replicating further. So, if you get better then you have antibodies. But, antibodies are a numbers game and so your numbers increase after a recent infection just in case it returns. I believe it’s different for every person, but I took daily antibody tests after my second vaccine shot and on day 6, I had none. On day 7, I had many. I was just using a rapid test so no indication of numbers or whether or not they were neutralizing, but I imagine they continued to increase until around week 2, then they probably began to decrease over the next 2-6 months and beyond.

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mrwolfisolveproblems t1_j1bph0g wrote

Reply to comment by DontWorryImADr in How do fusion scientists expect to produce enough Tritium to sustain D-T fusion (see text)? by DanTheTerrible

Battery end of life with EVs is the 1000 pound gorilla in the room that no one wants to acknowledge. All these states passing laws to ban sales of ICE vehicles have put zero thought into it that’s for sure. Not to mention the huge cost to consumers of said replacements. So insane to me that these problems are not close to being solved with EVs being jammed down everyone’s throat. I guess necessity is the mother of all invention, so hopefully mass EV adoption will drive solutions to these problems. End of sidebar.

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