Moreno

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About Moreno

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  1. For example, for automotive applications. Energy is measured not in volts, but in MJ/Kg or W-h/Kg. It is not only voltage is important, but also electrochemical equivalent (how many electrons you can obtain per atom). Aluminum can offer 3 electrons per atom, what is good.
  2. This is what some person (who seem to be profi in batteries) claimed. And for example: https://docs.wind-watch.org/braga2017.pdf If I no make mistake Fermi energy depends primarily (if not completely) on electron concentration inside of metal. Therefore electrons are prone to flow from high Fermi energy (higher concentration) to low Fermi level.
  3. https://en.wikipedia.org/wiki/Electrochemical_potential
  4. I've met such statements that energy which a battery can deliver roughly depends on Fermi energy differences between anode and cathode materials. If we look in the table with Fermi energy values for pure metals, there exist large difference between Aluminum (12 eV) and Sodium (3 eV). http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/fermi.html#c1 Both materials are inexpensive. Can we create an Aluminum-Sodium battery and if yes, how much energy will it offer?
  5. It seems like the whole idea is based around the claim that regular Lithium on anode converts to some mysterious low Fermi energy form on the cathode. http://pubs.rsc.org/en/Content/ArticleLanding/2016/EE/C6EE02888H#!divAbstract But it is not clear if Lithium is transferred at all and what is this low Fermi energy form of Lithium. How Fermi energy of Lithium can change?
  6. Why this memory consolidation can't happen during state of wakefulness? This isn't fair comparison, but we need not to turn of computer periodically in order to get long term data storage consolidated.
  7. I do not know about other people, but personally I start to feel psychological discomfort even sooner than any serious physiological discomfort if prevented from sleep long enough. I just cannot tolerate boring monotony of surrounding reality for a long time and it becomes quite a strong suffering. My brain demands to get disconnected and after sleep I start to perceive reality in a fresher way. It looks like a clearly psychological need to me. But why exactly sleep does have this effect is a good question. Looks like some magic to me.
  8. ^ So, if I understand you correct you are convinced that our need of sleep is based on purely physiological needs and our psychological comfort or discomfort based on presence or absence of sleep is rather an illusion based on physiological reasons...
  9. There exist a speculations to explain a physiological need of sleep by claiming that brain is cleaned of toxins during the sleep time. However it is not explained exactly why this toxins cleansing can't happen gradually during waking time and why there is a need to disconnect the full consciousness for this reason. But beside physiology in my perception there is a purely psychological need of sleep. Because sleep gives a person a mind-refreshing effect. If a person doesn't sleep too much and doesn't even need a lot of sleep for a physiological reasons he/she starts experience an unbearable "boredom" of surrounding reality which starts to surround him with and squeezes his mind. And after sleep person feels refreshing perception of surrounding reality like he is a "newborn" and the agonizing monotony of surrounding reality steps back for another day. This wonderful "refreshing" capability makes me interested a lot. There is a common scientific theories which are trying to tie sleep process with processing of data gathered by brain during the day and importance of dreams for this reason, but still it doesn't explain why this data processing can't happen somewhere in the subconscious during the state of wakefulness and we need to disconnect our full conciousness. It is known that many animals have either decreased need of sleep or anomalous type of sleep. For example giraffes sleep only 1 hour a day/night and many animals including see mammals, birds and reptiles have mono-hemispheric sleep (they never loose full awareness completely). Quite interesting that in my own perception (and that of other people) sleep has this wondering reality perception refreshing capability even it is hardly associated with any dreams. For example it happens rarely that person goes to sleep and wake ups "instantly", but in reality many hours have passed. I think it is an indication for lack of dreams, but wonderfully, people feel very refreshed after that type of sleep. I wonder, what could be done or how human brain have to be organized, at least theoretically, in order to have perception of reality always fresh like he just woke up after a good sleep and in this way we would have no psychological need of sleep. Is it all explained by dreams or there is some other explanation? In reality dreams aren't too different from a common reality that surrounds us. People see in dreams themselves walking on the streets, visiting buildings and known places, talking to other people. So, why do they make such a strong effect on our perception of reality when we wake up (if they do)? It makes me fascinated when I think about possibility to have a fresh perception of reality always and need no sleep for this. Any ideas how could it happen?
  10. Someone told me that energy which a battery can deliver is approximately proportional to a difference in Fermi energy between anode and cathode. I guess it may not relate to metal-air fuel cells because Fermi energy is applicable more to a metals than gases. Fermi energy is also known as an electrochemical potential. So, if we look at Fermi energy table for pure metals, then there is a substantial difference in Fermi energies between Aluminum (11.7 eV) and Sodium (3.24 eV). http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/fermi.html#c1 If we will make a battery with aluminum cathode and sodium anode (or contra) how much energy will it deliver? It is also interesting that though Aluminum and Sodium have different Fermi energies they both can serve as a high energy density anode in metal-air fuel cells.
  11. What if we take a short GHz wave and change its phase velocity? Will it lose ability to carry lot of data? Will it gain ability to spread for a longer distance?
  12. I meant some waves in which we could pack as much data as in GHz frequency, but which can propagate as well as 1KHz-30MHz frequency. The methods you've mentioned still don't offer that possibility?
  13. Short waves have advantage when we need to code a lot of data. But they can't regularly spread for a large distances. (unless we use an expensive satellites). Long waves on other hand can spread for thousands of kilometers, but cannot code a lot of data. Is there an absolute connection between frequency and wavelength? Can we modulate short waves somehow to increase their effective wavelength? For example, wavelength depends on phase velocity. Does it mean that modifying phase velocity we can change wavelength regardless of frequency?
  14. There is no competitive ways to store/transport hydrogen. Gasoline energy density = 34 MJ/L. Hydrogen (compressed at 700 bar) = 9 MJ/L. Hydrogen liquid = 8.4 MJ/L. https://en.wikipedia.org/wiki/Energy_density Fuel cells have many fundamental problems difficult to overcome. PEM fuel cells efficiency = 45-50%. Close to 40% for a system. Alkaline fuel cells claimed to reach 70%, but much larger in size than PEMs and are quickly poisoned. Still they may be used in some London's taxies. http://www.parliament.uk/edm/1997-98/1597 Heat engine efficiency depends on heat sink temperature. Modern ICE are still far from a limits possible.
  15. Probably, I've posted a post in the wrong thread. It belongs to "plasma cushion levitating cars".