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Everything posted by Moreno

  1. I don't think that the costs of gasoline transporting constitute huge part of gasoline price at the gas bar. The same probably goes with Aluminum. Neither I expect huge costs for picking up the oxide. (if it has to be picked up at all).
  2. Do you think nuclear, hydro and renewables can't solve the problem? Moreover, Aluminum can be smelted in remote areas where cheap renewables are available and later transported to the cities in powdered form.
  3. Of course not. But even at the current electricity prices and EV efficiency could be quite competitive with gasoline.
  4. Is it theoretically possible?
  5. 1) Aluminum oxide smelting. 2) Store it in hermetic boxes. Possibly in wet form to reduce risk of ignition. 3) An Aluminum-air galvanic cell. 4) Aluminum energy density is 31 MJ/kg, 84 MJ/L
  6. How they were able to create an illusion of a black/dark colors in this 3D laser whale image? Don't black/dark colors assume an areas of light absorption?
  7. How realistic it would be to make a metal-air fuel cell which could be charged by an aluminum powder and release pure aluminum oxide powder as an "exhaust" right on the go?
  8. Why Zync-air rechargeable batteries suffer for low efficiencies? Is it an inherent problem of all metal-air batteries? There also seem to be a large difference between Coulombic efficiency (around 90%) and roundtrip voltage efficiency (around 55%). Is there any ways to solve this problem somehow?
  9. What about water vapors? Don't they suppose to scatter light strong enough to prevent good visibility?
  10. We cannot see the stars in midday because atmosphere is not transparent to our vision. How then the satellites make the pictures of Earth surface which is perfectly visible regardless the atmosphere?
  11. So, at what depth it will stop working completely?
  12. What type of cheap and non-toxic liquid can efficiently absorb radio and microwaves? It could be a solution. So, for example, when you put a mobile phone into this liquid, it doesn't suppose to work (not because of a short circuit).
  13. Nissan promises to release later this year a new version of the LEAF with claimed range up to 226 miles. https://www.greencarcongress.com/2019/03/20190304-leaf.html I wasn't able to find an exact official specs on the 62 kWh battery, but some sources claim it weights around 300 kg. If this is true, then problem of a normal plug-in hybrid is almost solved. We can cut battery in half (150 kg) and obtain a hybrid with decent range of 113 miles. Maybe some additional not very large set of a high power batteries (similar to Lithium-titanate) will be needed to compensate for the power peaks. I wonder how Nissan was able to achieve that energy density and what kind of materials and rare metals they use. If this type of batteries could be produced at moderate price we are on the verge of plug-in hybrid revolution.
  14. Now China produces 1/3 of total manufacturing production in the World. https://knoema.com/atlas/topics/Economy/Short-term-indicators/Industrial-production I think when this number will start to get close to 50%, World start to face a new reality. Total China's population is 1.5 times larger than population of all modern developed countries combined (US, Canada, Australia, Western Europe and Japan). I think somewhere after 2050 China will start to have serious opportunity to extend nearly total economic and political control on depopulating Russia, Ukraine, Central Asia, Mongolia and several other medium or large countries in Asia and throughout the World. So, the New World is looming...
  15. In my understanding majority of modern health disorders (in civilized countries) aren't caused by infections.
  16. I'm thinking about something that could be much less harmful and less expensive than modern prescription drugs.
  17. What could be a future alternatives to the chemical drugs/medication?
  18. Is it higher porosity and smaller size of pores which are responsible for much higher energy density of supercapacitor vs. electrolytic capacitor? Or there is something else? On other hand electrolytic caps are able to withstand much higher working voltages what suppose to contribute to energy density.
  19. Forming gaps between what and what? Can you explain it more in detail? In some monovalent metals (for example Sodium) all valent electrons are located in conduction band. The valence band is completely empty. In order to conduct holes a material needs to have partially filled valence band. How can you inject holes in a material if its valence band is completely empty? Also, if forward bias action of a p-n junction or (possibly) metal-semiconductor ohmic contact is based on constant carrier recombination, how it comes that very little energy is wasted? Doesn't intensive carrier recombination suppose to consume lot of energy and furthermore lead to material overheating? (What suppose to increase resistance in metal at least.)
  20. Principally, similar question can be related to p-n junction. But if in the case of p-n junction there is flow of holes into n-type region (forward bias), how there could be flow of holes into metal in the case of metal-semiconductor ohmic contact? Monovalent metals typically conduct no holes...
  21. Isn't an ohmic contact a variety of a metal-semiconductor junction? In the case when the later doesn't have rectifying properties? My question was: why contact of a higher work function metal and a lower work function P-type semiconductor is an ohmic junction? When we apply potential and make electrons flow from metal to semiconductor in the case above doesn't semiconductor suppose to case resistance to such flow? And also, if electrons start to flow from metal to semiconductor, doesn't they suppose to recombine with holes and make semiconductor depleted for any kind of carriers further increasing the resistance? How P-type semiconductor can conduct free electrons, those which belong to conduction band of the metals?
  22. Sorry, in the my first sentence I've used a generalized expression "Schottky type of contact" for both Schottky junctions and ohmic contacts. Probably, I would have to use "metal-semiconductor junctions" instead.
  23. It is claimed that Schottky type of contact between low work function p-type semiconductor and higher work function metal creates an ohmic contact in which current can flow both sides almost fluently with very low resistance. It is also claimed that electrons have tendency to flow (when no potential is applied) from low work function material to higher work function material. So, when low work function p-type semiconductor comes in contact with higher work function metal, a p-type semiconductor will not let electrons from metal enter into semiconductors and will push them back. It seems a bit counterintuitive to me, because how in this case could it be an ohmic contact? Doesn't p-type semiconductor with lower work function suppose to cause resistance when potential is applied to make electrons flow from metal to semiconductor? Furthermore, if electrons penetrate from metal to p-type semiconductor under applied potential, doesn't they suppose to recombine with holes and create a depletion zone poor for any charge carriers and further increase resistance? https://materion.com/-/media/files/advanced-materials-group/me/challenge-of-applying-ohmic-contacts.pdf
  24. I think that additional genes of altruism, kindness and spirituality would be definitely not a spare for humanity.
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