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John Cuthber

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Everything posted by John Cuthber

  1. If you start with a molecule or atom in an excited state then you can ionise it using relatively low energy photons. There is no theoretical lower limit to this so even radio frequencies could ionise something that was already sufficiently nearly ionised.
  2. What are you doing that needs that dry an atmosphere? Anyway, the water permeation through the gloves will make more difference than the drying agent you chose.
  3. The point is that yes a magnet can push metal, but only if it's the right metal. As a matter of fact, magnets push water but not very hard.
  4. How will we know when we have won ie what will be the state afterwards? Are we getting measurably closer to that state? If we are not doing so then are we at a stalemate? Does a stalemate that keeps killing our troops count as anything other than losing slowly?
  5. If you assume that the aquarium pipe is pretty soft then the end plugs won't move in or out. The water pressure will squash the pipe until the pressure in it is 3 bar. There will then be the same pressure inside the pipe as outside it so there's no net force on the plugs. If you used a stiff metal pipe or very flexible plugs then the plugs would move in. If you used stiff plugs then the pipe would deform and they would stay put.
  6. "I believe part of bascule's point was that the polonium is "glued" to your lungs by tar, whereas the potassium in your food just passes through." It's true that the K passes through, but since I keep replacing it by eating this doesn't matter much. I'm still roughly 8000 times more radioactive than the Po in a cigarette. There's Po in food too; less than in cigarettes but most people eat more food than they consume tobacco. http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=11225703&dopt=Abstract I have a good reason for ignoring the assertion that Po
  7. "So your argument is why not leave a radioactive compound in cigarettes because cigarettes contain other carcinogens?" No My argument is that the tiny ammount of Po in tobacco is unimportant compared to other toxins there. Removing it would be like trying to remove the lead- sure, you could do it, but it would make a lot more sennse to spend the money on anti smoking campaigns. "That would be a strawman which confuses a fatal dose with a carcinogenic dose." No it's an illustration of how small the quantity is. Comparing one carcinogen (Po) with 2 others (Cd and As) doesn't look unreason
  8. "Perfect example of repititious propaganda regurgitation. Just say it over and over enough... Still waiting for your facts and evidence to support your claims...any of them. " It must be true, it's on CBS. http://www.cbsnews.com/blogs/2007/07/09/couricandco/entry3033134.shtml
  9. "Send a letter to the Department of Energy suggesting they regulate nuclear materials in tobacco the same way they regulate other nuclear materials. " I understand the guy you want to is called NORM. Probably the main reason this is being ignored by the authorities is that it's not very important. If they took all the Po out of tobacco there would still be plenty of other carcinogens left so what's the point? The quantity of Po in cigarettes is estimated as about 10 Bq each. So Mr Litvinyenco (sp?) could have got his fatal dose by smoking about a billion cigarettes. I think the ounce and
  10. Galton, the father of eugenics, made the same point (about the higher fertility of "the lower classes") in 1883 IIRC. Since then the standards of living and of education have increased more or less continuously.
  11. "In a similar way to how you see in IR" I don't see in the IR; that's pretty much the definition of IR. There is a difference between saying these things look the same (ie have the same visible reflectance) but don't have the same IR reflectance (which is common enough) and "these things look different in the IR" which only makes sense if you can look in the IR which you can't. I know things can reflect IR or UV differently, even if they look the same. In fact, everything does. If you look at a large enough range of the spectrum then no 2 things will reflect identically unless they are the
  12. I think YT2095 is most of the way to the right answer. Almost all "polycarbonate" is bisphenol A polycarbonate. Comparison of the IR against a known sample is easy and (with the right kit) non destructive. You can hydrolyse the stuff and get the monomer (well, I'm not sure about getting the CO2 part of it) but as YT2095 says it's slow. While this reaction is slow, it's quite fast enough to damage polycarbonate objects, in particular alkalies reduces the strength and, since polycarbonate is usually used where its strength is important, that's bad news. Pyrolysis would probably give fairly reco
  13. "Yes, you can make things that look different in IR or UV than they do in the visible." I know how things look in visible light; how do things look in UV and how, unless your eyes are UV sensitive, do you know? Seriously, what does that sentence mean?
  14. "My point, was on this issue, was that IMO smoking is a *something to do* habit, opposed to some compulsion to feed a chemical into the brain." I know a number of ex smokers who don't share your opinion. The medical establishment tends to agree with them. The success of nicotine patches also indicates that this is a real chemical addiction. "The smoke related cannot be determined IMO." Statisticians and epedemiologists do not share your opinion on this.
  15. What do you mean by " way of making an entire material "? All that article says is that, in the same way that things are camouflaged by making them roughly the same colour as the background, they can be camouflaged from the point of view of an IR camera by making sure they have the same IR reflectance spectrum as the background. A fairly obvious wayto do this it to cover them with the same material as the background. For example, if you want to hide your tank in the desert, make sure it's covered with sand. If you want to hide it in the forrest, cover it with leaves. None of this will he
  16. Intrerestingly, we now have proof that man can create life but no such proof for God. Does this mean that if God is subsequently found to be able to create life He is playing man?
  17. Lucaspa, The images raise awareness of both greenpeace and the whaling. I wonder how you expect greenpeace to do anything without raising money to cover the costs of doing it.
  18. "Then lets move to Asbestos, which claimed was the cause for ALL respiratory problems for years" Who made any such claim?
  19. Well, OK I agree that if your father died in a crash but it's listed as smoking related then the stats are skewed. I'm pretty sure that the statistical link between smoking and, for example, lung cancer is so well researched it's practically certain. I work measuring things- generally concentrations of pollutants in air. I know that some time ago when I was involved in measuring exposure to a chemical that people were working with and some other people were asking the same workforce to fill in a questionnaire about health, lifestyle etc. we got a rather disappointing result. The measureme
  20. I'd not bother with magnetometry. I'd dissolve the tablets in dilute acid, oxidise with H2O2 to get it all into Fe(III) then measure it colourimetrically. If I wanted to be classical about it I'd not oxidise the extract, I'd send it through a Jones reductor and then titrate the eluant with KMnO4 I have a feeling that you would need to do some sort of purification of the coffee extract before you could do a UV determination on the caffeine. I'd bet on chromatography. Not sure about the sunscreen- some sort of absorbtivity measurement.
  21. Don't forget that all the concentrations there have to be expressed as normality ie gram equivalents per litre (which is that same as molarity for nitric acid, but not for sulphuric). Only bother to read the next bit if you would otherwise point out the error. Strictly the units only need to be g eqiv / volume- it would still work in cubic feet but that's just complicating things.
  22. I think insane alien is mistaken. It would work. The alphas would plough into the other plate and charge it + while the electrons left behind would charge the alpha emmiting plate -. The same goes for the betas (the other way round). In fact, you only need one source.
  23. Also, while it's hot make sure it doesn't oxidise in air and give zinc ozide and SO2. If you are trying to get something to glow in the dark then I think the big problem is that the real stuff is made in a rather complicated way to get the best performance.
  24. Interesting chain of logic. I asked precisely one question; it was this "Still, what other product can you think of which, when used in accordance with the manufacturers instructions, has a 50:50 chance of killing you?" It seems the answer is "There is a 100% chance that eating carrots will kill you. A survey made in 1900, showed that every one surveyed had at some time eaten a carrot or carrots. Almost all are now DEAD, and the couple still around really look bad, expected to die soon." BTW, are you sure about what you said. I'm quite happy to believe that they record incidence of tobacc
  25. Err, it's a fair point that the media exagerate things like it's going out of fashion, but since plutonium is roughly a million times more radioactive than uranium it's a reasonable candidate for this list. It has an LD 50 of about 50 µg/kg which is pretty low and it certainly got a mention early on in this thread. I think the problem with including it is that you would also need to include every radioisotope with an apropriate half life (too short and you will never get enough into someone to kill them; too long ant it won't do any harm).
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