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John Cuthber

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Everything posted by John Cuthber

  1. There are, no doubt, many errors in wiki. So what? The page about non-newtonian fluids was correct when I saw it. Nobody has actually said it's wrong.
  2. "Originally Posted by John Cuthber OK if 30 % of the Po is related to smoking then 70% isn't. If 30% of blood polonium..." Hey, you cited that paper- if it doesn't talk about what you though it did don't blame me. The only analytical evidence we seem to have here says that more of the Po is from other sources; not smoking. "Well, to begin with, your results contradict peer reviewed scientific research. I've cited two papers here... Martell's experimental measurment of radiation dosage and the paper measuring 210Po. You're contradicting them both." For the record you also cited a paper (the 2nd one), then tried to discredit it because it measures polonium in the wrong tissue. In doing so (ie showing the Po moves from the lungs to the bloodstream) the paper also disproves your hypothesis that Po lodges firmly in the lungs; at least some of it gets into the blood. Wait a minute, that wasn't strictly your hypothesis was it; it was part of the other peer reviewed paper you cited. OK you cite 2 papers and they don't agree; Po either is; or is not; localised in the lungs depending on which one you pick. There's nothing wrong with contradicting any paper by pointing out that it doesn't seem to make sense. Why worry about the radiation from a cigarette when I'm 4 orders of magnitude more active than it is? Contradicting papers is perfectly reasonable particularly when faced with 2 that don't agree. "You're demonstration of ambient radiation being "thousands of times" worse than cigarettes is based on a pyramid of assumptions, everything from how much air you breathe to the specific radiation dosage and method of administration. If you're trying to compare radiation dosage, shouldn't your results be in rads? And furthermore, the dosage is going to vary based on a multitude of factors which can't simply be calculated but instead need to be experimentally measured." Everything in science is based on assumptions. I explicitly listed most of them like how much I breathe and so on. If you can find evidence to refute those assumptions then fair enough, I will look at that evidence. Otherwise I'm afraid that, since you are the one puting forward a hypothesis that is, to say the least, "has been addressed in the past and has apparently lost popularity in the scientific community" the burden of proof is on you. "The real problem is there are scientists writing peer reviewed papers on these issues all the time. They're confirming their findings experimentally. You're doing some off-the-cuff calculations which contradict experimental, peer reviewed research." Interesting isn't it? There's plenty of evidence out ther about Po levels and background radiation. I really am 5 or 10 thousand times more radioactive than a cigarette, yet they seem to be blaming the Po for cancer. Here's an amusing thought. Papers tend to regard something as "proved" if the statistics show an effect stronger than the 95% level of uncertainty. That means there's a one in 20 risk of getting that good a result as a fluke. Plenty of journals contain roughly 20 papers in each issue. That means that they publish roughly 12 wrong papers in each year (assuming they are monthly and the odds ratios are not much better than 95%). OK, why have this odd faith in peer reviewed papers? "Originally Posted by John Cuthber It's true that the K passes through, but since I keep replacing it by eating this doesn't matter much. Can you find a paper to back that up? You're comparing something which is cleared by natural processes and passes through the alimentary canal to something that lingers and accumulates inside of the lungs...." "Why do you ask if I can find a paper that shows that I eat food that contains potassium. Why in heaven's name should I bother to prove something so plainly obvious? Don't you understand that there is K in all my tissues, lungs included, so the relative sensitivity of the lungs doesn't matter. Strawman? You're contradicting two papers I linked. You could at least do me the courtesy of finding at least one paper which confirms your position, specifically in regard to radiation dosage." No it's not a strawman. A strawman would be where I distort something you say into something daft and attack that rather than what you actually said (and don't forget those two papers contradict eachother) What you realy did was ask for a paper to prove that potassium is a natural constituent of the body maintained at reasonably constant levels. That's already daft; I didn't need to distort it. There really is potassium in me or I'd be dead. It really is maintained at fairly constant levels (about 0.4% w/w (a figure that you can look up if you want, but trust me I don't need to lie and I'd have more sense than to do so in front of a bunch of scientists who know how to use google (there's more than one type of peer review))). The potassium is not "cleared by natural processes" at all. It is maintained at a fairly constant level. It isn't just in transit through the gut; it's absorbed, distributed throughout the body and excreted mainly by the kidneys (thanks by the way for answering the question I posed "Don't you understand that there is K in all my tissues") If you want to look up stawmen you might have a look at the other common logical falacies. They include "argument by authority". An example of that is to say that something must be right because it's been peer reviewed.
  3. I think you may find I didn't so much miss the point as give you a possible answer, Since you seem to have missed the point, here it is again. "You might be able to find a dilatant mixture of a solid and liquid (that behaves like cornstarch and water) where the 2 components have the same refractive index. Even then you will have problems because the optical dispersions of the 2 materials are likely to differ. I might try powdered glass in glycerine if I were looking for such a mixture." Just for the record our collective psychcic abillities are somewhat limited so, since you didn't tell us what you wanted it for, we might not have been able to read your mind and find out.
  4. What exactly do you mean by "air is heavy. 100x air is very heavy". Even at 100 bar air is less dense than water.
  5. I'd choose almost any other transition metal first. Ni can get lost as the carbonyl when you ash it. This isn't an impossible problem to deal with but why make life more difficult than you need to. Measure Cu or Mn or whatever. You can get round the problem by wet ashing (effectively boiling with acids untill all the organics are destroyed) but that's messy and you need high purity acids.
  6. It looks like a neat idea. A couple of thoughts struck me. We are going to burn the coal anyway because, at least in the short term, we need the energy. We might as well recyle the CO2. In the slightly longer term we can reuse the "diesel" to run the power station rather than engines. That way you get, effectively, a solar power station. With combined heat and power technology we can squeeze even better efficiency out of this idea.
  7. http://www.skeptics.com.au/journal/1992/2.pdf See page 12.
  8. Here's the abstract of that paper. Institute of Atomic Energy Research, King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia. eshabana@kacst.edu.sa A preliminary study of 210Po concentrations in the blood of some smokers and nonsmokers is presented in order to evaluate the contribution of smoking to total blood 210Po in Saudi population. Blood samples were collected from 30 volunteers and analyzed by high resolution alpha-spectrometry using a radiochemical technique. The technique is based on the separation of polonium from other components of the sample by wet ashing with an HNO3/H2O2 oxidizing mixture and spontaneous deposition on a silver disc under the relevant conditions for alpha-particle counting. The results indicated that a significant fraction (about 30%) of blood 210Po is related to smoking. OK if 30 % of the Po is related to smoking then 70% isn't. Thankyou for proving my point that most Po exposure is not related to smoking. You wrote "I'd really help if you could find papers to support your position, rather than trying to do your own calculations." I'm not sure what you would help but anyway, what's wrong with me doing the calculations? More importantly, can you explain what, if anything, I have done wrong in that calculation? I know I simplified thigs a lot but when I'm thousands of times more radioactive than a cigarette those simplifications don't make a lot of difference. Why do you ask if I can find a paper that shows that I eat food that contains potassium. Why in heaven's name should I bother to prove something so plainly obvious? Don't you understand that there is K in all my tissues, lungs included, so the relative sensitivity of the lungs doesn't matter. Yes I ommited the bit of the sentence that is redundant. If the theory were popular it would still have been generating publicity If it were generating publicity then it could have been said to be popular. So what?
  9. 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.
  10. 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.
  11. 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.
  12. 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?
  13. 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.
  14. "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 in smoke is responsible for the lung cancers in smokers. Typical indoor air has levels of radon about 50Bq per cubic metre. (the action limit is about 3 times higher) I breathe about 20 L/min so I get through a cubic metre in about 50 min. That's roughly 1 Bq per minute of radon that I breathe. The Rn is, of course, accompanied by the decay products which are typically stuck to dust particles. A lot of this is cleared out by the various mechanisms but since I keep renewing it that's not as much help as it looks. So I get exposed to the effects of roughly 1 Bq of each of the 2 isotopes of Po in the decay chain as well as the other things (2 Bi and 2Pb isotopres). In order to double my inhaled ,Po- derived, radiation exposure I would need to smoke a cigarette or 2 every minute (assuming all the Po in the cigarette ends up in my lungs which is questionable). Nobody smokes that much, yet smokers have incidences of cancer far more than twice the incidence of cancer found in non smokers. The issue here is not "we ignore it because they are smokers who should know better"; it's "we ignore it because it's not significant compared to background exposure". Smoking certainly adds to your Po intake, but not much. A 20 a day smoker takes in an additional 20Bq of Po A non smoker takes in about 1500Bq by breathing. The difference between 1520 and 1500 is not a plausible cause of the raised cancer rates in smokers. The tobacco industry is guilty of some pretty poor behaviour but this isn't a big deal. BTW, here's the bit from that paper that you seem to be ignoring "The Martelll "Hot Particle Theory" has been addressed in the past and has apparently lost popularity in the scientific community ".
  15. "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 unreasonable to me. There's another really important distinction between food and tobacco. Nobody really needs tobacco; if it all disapeared tomorrow it wouldn't kill anyone. Surely it makes more sense to worry about other things first. Natural K gives about 30 Bq/Kg. How much more radiation am I exposed to from the K in my food than from the Po in cigarettes? Well, I'd need to smoke a lot if the figure given here is right. http://www.npp.hu/mukodes/aktivitas-e.htm Am I worried about this? No, not even taking the effectiveness of alphas or the cumulative effect from the Po into account.
  16. "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
  17. "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 a half of lead he would have picked up might have got him first. Failing that the couple of ounces of cadmium or the quarter ounce of arsenic might have taken him out. http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&list_uids=11941445&cmd=Retrieve&indexed=google It's not as if the same fertilisers are not used for other things. Brazil nuts often have raised radium levels but that's not going to stop me eating them
  18. 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.
  19. "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 same material. That's why I sugested using, for example, sand to look like sand. I'm still trying to work out what the OP's question meant.
  20. 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 recognisable debris if you GCMS it. What sort of kit do you have access to?
  21. "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?
  22. "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.
  23. 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 help if the enemy has thermal imaging gear.
  24. 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?
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