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Moreno

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Everything posted by Moreno

  1. One more attack on the second law was attempted: Read more at: https://phys.org/news/2017-02-physicists-erasing-energy.html#jCp
  2. No. I need some substance which stays solid in wide temperature range and remains solid on contact with water. Only water suppose to dissociate on contact with that substance.
  3. Is there any solid-state substance which can work as an efficient water solvent?
  4. There is already at least one type of electric motor that uses no magnets or electromagnets at all. This is the ultrasonic motor. https://en.wikipedia.org/wiki/Ultrasonic_motor However it has some disadvantages, what would be an issue with any new type of a motor. For example, high initial price and vulnerability to dirt.
  5. Are you sure that if we mix water and ethanol together, ethanol and not water would be a solvent?
  6. Is there any substance in which water can dissolve?
  7. There is such a thermoelectric phenomenon: when you will heat one end of a conductor, semimetal or semiconductor, electrons will flow from a hot end to the cold end (like any gas when it expands) and presumably you will get higher density of electron gas on the cold end than it initially was. If some material has 0 Hall coefficient and most likely the same mobility of electrons and holes then electrons and holes will move to the cold end to the same extent and therefore we will likely have larger density of electron-hole gas in comparison to its initial state. If I'm correct in my assumptions and there is such a phenomenon as electron-gas compressibility, is there any limit (in different materials) to which electron-hole gas could be compressed and which physical effects will be associated with the compression?
  8. Which methods are best in water molecules dissociation to obtain OH- and H+ ? Lasers, microwaves, electric current? Which methods are most energy efficient to obtain as much as possible ions at a time? Which frequency have to be used?
  9. There are claims that by 2020 we may have tabletop optical supercomputers capable to perform exaflops of operations per second. Are these statement grounded? https://www.extremetech.com/extreme/187746-by-2020-you-could-have-an-exascale-speed-of-light-optical-computer-on-your-desk
  10. https://webcache.googleusercontent.com/search?q=cache:dII1QJHWYlUJ:https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19870001331.pdf+&cd=1&hl=en&ct=clnk&gl=ca Can mhd generators really be that efficient (70%)? If yes, why they aren't widely used yet? Which methods could be used to dissociate water molecules present in water vapour in mhd generator?
  11. Well, this is unlikely, of course, but I think that in distant future portable Stirling engines may find wider use (for example in vehicles) if new ways to use nuclear power will be invented. A portable Stirling engine is one of the best ways to convert energy of a portable fusion reactor...
  12. If some chronically ill person is forced to take lot of medication daily, harmful to liver and kidneys, is there some medication to prevent liver falure?
  13. So, there are holes in metals which could be regarded just like holes in semiconductors?
  14. Something less toxic? For example a person works as a security guard overnight or as a soldier. Which substances can prevent falling asleep during the night or two? Tolerance to caffeine develops quickly.
  15. Principally, you can buy nicotine, but it's highly toxic in large doses.
  16. Which strong stimulants available overcounter, to which no tolerance (or little) develop?
  17. If I no make mistake, Helium molecule is smaller than Hydrogen.
  18. I want to buy an EEG device (used one, but in a good order). And need an advise. I'm looking for a something under $1000 price range, but they are more expensive, commonly. I just need a device which could make a difference between a common sleep stages such as REM, NREM (stage 1, 2, 3, etc) etc. I don't need some complicated analysis. I will be satisfied if it could be connected to a computer. Also, I would be glad with EEG device which could be connected only to those parts of head with no hair (brow, temples). Could you explain why EEG devices are so expensive? By idea they should cost no more than a portable FM radio. They just convert electric impulses to a readable feedback. Currently they started to experiment with neurofeedback for a gamers. How suitable could it be?
  19. I think geothermal power will be more profitable if methods to transport electric energy over large distances with very little looses wil be perfected. Or you could use geothermal energy to produce aluminum and ship it somewhere.
  20. I have doubt in it. A positive Hall coefficient could be often found in pure metals. For example in Bismuth. Does it mean electrons have negative effective mass in Bismuth? As well as in Zinc, Cadmium etc. I have large doubts in it.
  21. How Positive Hall coefficient in metals could be explained?
  22. What do you think about the following article: http://www.nature.com/articles/srep06208 They claim a frictioneless engine could be created. Not a real life engine again?
  23. Why? It wouldn't violate a fundamental laws of TD?
  24. 1) Machine of the second kind is NOT capable to produce work? 2) "The second law of thermodynamics states that the total entropy of an isolated system always increases over time, or remains constant in ideal cases where the system is in a steady state or undergoing a reversible process. https://en.wikipedia.org/wiki/Second_law_of_thermodynamics ​ So, if entropy doesn't increase it doesn't necessarily violates the second law, but could be just a perfectly reversible engine?
  25. Usually, under "perpetuum mobile of the second kind" they assume a device which is capable to reduce total entropy of the universe. But what if total entropy stays unchanged and just cyclically increased/reduced in different parts of a system? Would it work like a perpetuum mobile (capable produce useful work) and will it violate the second law of TD?
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