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exchemist

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Everything posted by exchemist

  1. I think something is wrong with this diagram, or rather the accompanying labels. There is no way for the KE converter to avoid exerting a force on the enclosure, if it reduces the force on the back wall to 25% of the value at the jet nozzle. The force is equal to the the rate of change in momentum. If the KE converter reduces the force to 25% , it must absorb 75% of the momentum. This must generate a rightward force on the enclosure that is the missing 75%. You can't avoid that because of conservation of momentum, so far as I can see. If the KE converter imparts no force on the enclosure then you are telling us you could mount it on castors and it would not move, in spite of being directly in the path of the exhaust stream. That can't be right. Or is that really what you claim? You don't tell us how this KE converter works, but my guess is it diverts some of the exhaust out of the enclosure in some way. If you have measured a net thrust from the assembly, my guess would be that the diverted exhaust stream has retained a bit of rightward momentum and it is that which is producing the net thrust leftward thrust. If, on the other hand, there is truly no gas escaping from the enclosure at all, then the thing will blow up after a short while, due to build up of exhaust pressure in the enclosure. Unless I suppose the exhaust is steam and you condense it in the converter, in which case you can buy yourself some time before it fills up with water, before it blows up or stops functioning. Which is it?
  2. Yes, my understanding is one needs to distinguish between phase velocity, which is what changes with refractive index, and front velocity, which as I recall remains at c. But this is from a while ago now so I may be mis-remembering.
  3. I think I read recently that fire engines can't be electric, due to the power demand of the pumps. It may be that emergency vehicles should use whatever system is developed for lorries, for which batteries seem to too heavy. Hydrogen, perhaps, or some kind of renewable biofuel. But diesel fuel will around for a few decades yet, so exempting emergency vehicles so they can continue to use it would be quite rational.
  4. You can produce thrust (i.e. a force) without exhaust if the force is generated via a field of some kind, rather than kinetically. But as you give no details of the operating principle it is impossible to comment any further on the science. If you want to commercialise this invention without patenting it, then the best thing to do may be not to discuss it publicly until you are ready to offer it commercially. On the other hand that may carry some risk (only you can judge how much) that someone else meanwhile patents the same thing independently and stops you commercialising it. Some inventors make a "defensive disclosure" to prevent that possibility. (Once the invention is in the public domain, nobody can patent it.)
  5. OK, you seem to be in need of medical help, so I won't bother you further.
  6. That quote seems to come from the simple Wiki. I must say it feels wrong to me. I don't see how one can ever speak of a "field of energy". Energy is not a physical entity, but a property of an entity. Whereas, to my understanding, fields are physical entities. If the Higgs field confers rest mass, then I guess by the same token it confers rest energy. But let's wait for someone to turn up who understands the Higgs field. I don't pretend to. Perhaps we can both be enlightened.
  7. I think you just tease out the biggest crystal you can find - and then spend ages cursing and swearing as you try to tie it with a loop of cotton thread. Perhaps if you make a little slipknot you can tighten it around the crystal and trap it firmly enough to be able to suspend it. (I use slipknots at this time of year to tie the string round the paper and foil coverings over the Christmas puddings, before I steam them.🙂)
  8. exchemist replied to cornel's topic in Other Sciences
    Were and when did the pope say calculus should not be used to study the human soul? Which pope? I have not come across this. If there is any truth in it, it would be interesting to know, from the viewpoint of the history of religion and science. Can you quote a source?
  9. You could try hot filtration. You might need a fairly high temperature to bring down the viscosity of the molten wax sufficiently. There are industrial filtration systems that could do this sort of thing, in principle at least. For example, earth treatment of certain grades of lubricating oil is a well-established procedure.
  10. I'm not sure what you mean by containers in this context. These plastic pellets are used to make all manner of plastic articles, from ropes to dustbins to car dashboards. But yes, we do have to find biodegradable replacements for as many of these items as possible. And we will need to if we greatly reduce our refining of crude oil, as we wont be producing the naphtha etc to make the monomers.
  11. That's rather interesting though, isn't it? Tidal interactions dissipate kinetic energy as heat. In some cases, e.g. ocean tides on Earth, that dissipation is due to friction. Though I suppose that tidal distortion of solid bodies is mainly not due to friction.
  12. Friction is a distraction here. The basic point is @Ken Fabian's one, that any attempt to extract energy from the system will cause it to slow down and eventually stop. The energy you are trying to harness from the spinning flywheel is kinetic energy. If you remove kinetic energy from something, it slows down. The flywheel contains a finite amount of kinetic energy and that is the maximum energy you can obtain from it.
  13. SCIRP appears on Beal's List of possibly predatory journals: https://predatoryjournals.com/publishers/ More about its questionable nature here: https://en.wikipedia.org/wiki/Scientific_Research_Publishing And you are a spammer.
  14. No. Not recreational. Biologically necessary. These were semi-substantial alien beings in this sci fi novel, in which there were 3 sexes. All 3 were needed in the procreational act. The 3 sexes were designated male, female and parent, as it was the parent sex that did most of the caring for the offspring. I've forgotten a lot of it, but I do remember the quote from Schiller at the opening, which gave the book its title: " Mit der Dummheit kämpfen Gotter selbst vergebens." "Against stupidity the gods themselves struggle in vain."
  15. Yes: it's all nonsense. I don't know where you got this from, but it's full of arbitrary statements requiring explanation, from beginning to end. To take a few at random: - What does a "faster" rotation rate mean? Faster than what? - Why would centrifugal force suspend dust that is floating at the same height as the water surface and not the water as well? - Why would there be more D2O in the past than today? Deuterium is stable. - Why would higher density of water, whether in conjunction with centrifugal force or not, affect in any way the "stability" of Pangaea? - Why would the rotation slow? And then it gets worse. Hopeless rubbish, really.
  16. Not really. The XXY and XYY can be seen to arise from defective splitting of the pairs of chromosomes when sex cells are formed. The extra copies perform no function in gene mixing, which remains a process involving the merging of two sets, one from each of two parents. So there is no way they define additional sexes from a functional point of view. A third sex would imply some process like the 3 sexes in Asimov's "The Gods Themselves", in which it took a merging of Odeen, Dua and Tritt (Russian for one, two and three) in order to procreate.
  17. Not really. XXY and XYY are merely defects. They don't define a 3rd and 4th sex in any biological sense.
  18. The sex chromosomes you have, surely? You can be XY or XX. Or, in rare cases of genetic malfunction, you can be XXY or XYY. So far as I'm aware, all organisms that reproduce sexually, do so relying on 2 (two) sexes pooling genetic material.
  19. I'm not sure that the sodium ferricyanide will interfere to that extent. @John Cuthbermay know better. But as I recall, to grow a nice cuboid crystal you need to suspend a "seed" crystal, tied with a cotton thread or something, in a supersaturated solution and let it grow slowly and undisturbed for several days. What you want is for just one crystal to grow slowly, rather than a mass, suddenly. Maybe if you have some coarse salt you can select one grain and use that. Important that there are no other crystals or particles in the supersaturated solution or these will also be nuclei for crystallisation.
  20. This being a science forum, I doubt you will find many people here who subscribe to a literal Second Coming of Christ.
  21. My hovercraft is full of eels.
  22. Yes, more or less. I'm doing what you suggested and counting the carbon atoms, then applying the normal organic chemistry convention that all unwritten bonds to carbon are occupied by H. So a zigzag line will be a chain of -CHâ‚‚- units, for example, with a methyl group on the end because of the extra bond.
  23. OK, what's the mechanism in acid conditions? If we can see that it may be possible to work out how it would go in basic conditions.
  24. The cross thing is a tertiary butyl group: (CH₃)₃C-. The leg thing is an n-propyl group: -CH₂-CH₂-CH₃. As for how you synthesise them, that rather depends on what you are starting from. You can buy things like t-butyl alcohol or t-butylamine, or n-propanol etc. From your question, it seems as if you have part of the molecule already and you want to bolt these groups on. If so, what is the part of the molecule you have got?
  25. I suspect this was all just a piece of drive-by spamvertising. I'll be mildly surprised if our poster will be back to argue his corner.

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