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John Cuthber

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Everything posted by John Cuthber

  1. You can always distill the stuff to leave the caramel and sugars behind but I'd look on ebay for sodium acetate. http://cgi.ebay.com/Sodium-Acetate-Anhydrous-FCC-Food-Grade-Powder-1LB_W0QQitemZ130146100710QQihZ003QQcategoryZ104233QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (I am not afilliated with the vendor, not can I offer any evidence of their quality- when it coemes down to it I can type "acetate" into an ebay search)
  2. In my unashamedly biased opinion based on no study whatsoever, I believe that witches' spells are every bit as effective as Christian's prayers.
  3. A couple more things to think about. Sodium acetate is very soluble in water. It only takes 60 ml of boiling water to dissove 100 g of the salt. Vinegar is only a few percent acetic acid typically 4 or 5%; the rest is mainly water. You are going to need a lot of vinegar and a lot of patience boiling off water to do this experiment on the scale in that video.
  4. A couple of thoughts. First Does it matter whether Dawkins was a good scientist or not. He came up with or developed or publicised a few ideas. The meme is probably the best known of them. Is it a real concept that can be shown to exist? Well, I think it is and I guess Dawkins does too. Not only that I could propbably find you a few. Second, I note that only 26% of American students believe in witches. What do the others think? I know there are witches, I have met a few, and a warlock too. I don't think they are correct but to me they don't seem any different from the other religios types I have met. It makes as much sense to say "I don't believe in witches" as it does to say "I don't believe in Christians"
  5. Interesting article (wiki's often are). It also shows that unless you can get hold of exotic isotopes you are not going to get anything happening in something small.
  6. The quote I posted was the second use of the word. Your use was the first. Anyway, since you hadn't used it before post 17 it seemed odd that you expected me to have read it.
  7. "Gadolinium is paramagnetic above the Curie temperature." Very paramagnetic, and I still think you could use it for screening a field which was the essence of the original question.
  8. I didn't put the word in your mouth; you used it in post number 17 In that post you asked me to read what you had said about it. You hadn't said anything.
  9. "the terrorist thing is at best an Extremely pathetic Strawman, and easily dissembled by the statement violation of "live and let live" if they Complied with this, it wouldn`t be an issue now would it?" If they did then it would be a strawman. You seem to overlook the fact that they don't comply with it. Should I just let them get on with it? The whole point is that we are talking about groups with different outlooks-those who trust what they are told by priests of some sort and those who don't. If the other side won't let you live, then you cannot live and let live. "and it`s Also counter to what I said about the instincts (if you`ve forgotten or neglected to read) : "They only attack when either Threatened or Hungry. Humans being a Little (but not too much) more complex, have different ideas of Hunger (including Greed) and threat (perceived or otherwise)." That quote is the second use of the word instincts on this page. It's tricky to read what you said about instincts when you didn't actually write about it. If you are refering to the idea that I might be perceived to be a threat by someone because their preacher tells them so, then that's another good reason to prefer the evidence (ie that I'm not a threat) rather than the fairy tale. It's also a reason why I shouldn't tollerate that preacher. He might well persuade that person to attack me in the belief that it's a pre-emptive strike against an enemy. If the guy were in the habit of thinking for himself and gathering evidence he would spot that I'm not a threat.
  10. I don't plan to test Pu but my lump of gadolinium is clearly magnetic- you can pick it up with a magnet. It's quite a nice warm day here, definitely over 293K. It would be ridiculously expensive compared to steel, but you could use it to screen a magnetic field.
  11. "Different chiral centers will rotate the plane of polarize light in different directions." Correct "This is what characterizes left and right handed molecules" Not really, they are different and that's what characterises them as different. They sometimes have different crystal structures- in fact that's how Pasteur did the first experment to separate a pair of chiral molecules. If this "What is interesting, it doesn't matter whether these molecules are right side up, up-side down or on their side, they still cause the same affect." were true then the effect on polarised light of a crystal would be independent of the crystal's orientation. It isn't. The reason that it deosn't seem to matter for a bulk sample is that there are so many molecules at all sorts of angles and the effect you see is the average rotation. I think it's probably fair to say that the explanation or optical activity given here http://en.wikipedia.org/wiki/Optical_activity is more widely accepted than the rest of Pioneer's post.
  12. Rutherford was able to get hold of radioactive sources tat would be practically banned today. Also, he didn't prepare enough barium to make a precipitate. He irradiated some uranium and got a tiny quantity of baruin (among lots of other things). The then added ordinary barium nitrate then a sulphate to precipitate nearly all the barium in the solution (of course some would have stayed in solution.) The clever bit is that the barium he produced this way was a mixture of isotopes, some of them were radioactive. So the BaSO4 he precipitated was radioactive. Because the radioactivity from traces of radioisotopes of barium is easy to detect he didn't need to get all that much radioactive Ba in order to prove that it existed. All he needed to do was get a chemist (Soddy I think) to separate the radioactivity from any other possible elements in the periodic table and show that it was still radioactive. He got barium, but never anything like enough to see a ppt.
  13. Orlistat works by blocking the enzyme in the gut that digests the fat. Broadly, if you were to block 25% of the enzyme then only 75% as much fat would be digested (and therefore absorbed). Since, for any given person, the amount of enzyme is pretty much fixed the amount of drug needed to block it is also fixed. The problem with orlistat (and others like it) is that the undigested fats can cause problems. They are generally liquid at body temperature and the lower end of the gut is not comfortable with, or good at, holding back liquids.
  14. "imagine theres a horizontal planeA bove which the effects of gravity are not felt." there isn't one.
  15. They use hydrogen as a neutron moderator because it has the same mass as the neutron. The deutierum that alos gets used (because of a poor capture crosssection) while it is only wtice the mass of the neutron does a noticably poorer job. Aluminium is a lot heavier and will barely reduce the momentum of the neutron at all. Al simply isn't a light nucleus so it doesn't work very well, so yes, I read that bit of the article and I know what it means. Since it takes somthing like a foot of water to thermalise neutrons, surely you can see that a few mm of something that's a poor moderator is a non-starter. The lead is, of course, heavier still and therfore even less use. I'd still like to know why you think they can nuclear fuel elements in Al if you think it will block the neutrons. On the subject of the OP; where's the chemistry? A homogeneous reactor is possible; they happen from time to time by accident but you need a lot of enriched highly fissionable material to do it. http://www.uic.com.au/nip52.htm but if a single Uranium to Barium reaction has the power to move a grain of sand, then thousands of these at the same time Should make heat! Each fission event releases about 200MEV i.e. about 3.2*10^-11J A thousand of them a second would generate thirty two whole nanowatts. What do you plan to do with that? A reactor will generate heat, if you can get one to work. Many countries don't have the resources to do that, so I don't see you doing it any time soon. Possibly just as well if you plan to sheild it with Aluminium.
  16. "I should have used the polticially correct terms; chemistry creates conditions that could be mistaken for phenomena in physics. I didn't mean to intrude or be rude and crude. " This is nothing to do with terminology; it's to do with you not understanding what "hot" means. "Say we have a core of solid deuterium/tritium" No, don't say that, because the early universe was very hot, far too hot for these gases (one of which barely exists) to solidify.
  17. "I'll possibly get shot for this but..... Am I the only one who finds it amusingly ironic that the main claim to fame of the proclaimed leader of the "If I can't it or measure it, it doesn't exist" brigade is a philosophical/psychological concept that cannot be seen or measured?" OK so Dawkin's claim to fame is biology and you don't think that's measurable? I thought that people were doing mathematical modeling of repearted games and such looking at evolutionarily stable strategies and such that depend on the idea. Not a direct measure but a measure nopne the less.
  18. John Cuthber

    How Hot?

    A plane crash might not disperse all the fuel but it does a good enough job that the videos of plane crashes show fireballs. I think this is sufficient to bring the previous unsuported statement "I never knew airplanes had fuel atomizers and igniters installed... " into question. I think that's all bombus was pointing out.
  19. "There is H2 as a gas, liquid and solid." Didn't you understand the bit about it being too hot? "But in modern times, chemical affects can explain things like dark matter." Plain wrong. "Here is Florida during the summer you can see little dark gray clouds floating near bright white clouds. These are dark matter clouds." Plain wrong again. "What they are doing is absorbing the light with very little emission back." Wrong, yet again. Please go and learn some physics and chemistry before posting stuff like this.
  20. "Any suggestions for getting the last traces out?" Toothpaste on a bit of rag.
  21. " have to ask why you think a fire alarm Am241 slug would do the job?????" I didn't in fact I thought I made it preetty cleare that it wouldn't do the job. On the other hand I think it's about as potent a source as most people have access to. If you can get hold of a source a million times better then you only need to wait a million years or so. Heavy water is actually a less effective moderator than ordinary water, It gets used because its capture cross section is smaller. You would need more of it so the problem gets even worse because more water means more BaSO4 would dissolve and so you would need more to precipitate it. Essentially you are trying to build a nuclear rector. I don't think most governments are up to that never mind individuals. Also, re neutron screening. http://hps.org/publicinformation/ate/q1094.html 4th paragraph of the answer. I don't see why you think Al has some magic property of blocking neutrons. Al alloys are used as fuel cans in reactors. How well would they work if the neutrons never got anywhere? It has a capture cross section of about a quarter of a barn. Steel would do a better job.
  22. "there are only 3 metals that are naturally ferromagnetic" these 3 are Fe, Ni, Co, Gd and (I'm told) Pu.
  23. "In this span of time, chemical affects should be the dominant affect." Why? It's far to hot for any bonds to form and, until the hydrogen has colapsed into stars waited till they burned down a bit and got fused into the heavier elements, there's only hydrogen. Only one element doesn't give you a lot of scope for chemistry. Essentially no chemistry takes place until planets start to form.
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