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harlock

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  1. The heat of the burning wood comes from solar energy. So trees store solar energy by removing it from environment. The absence of trees causes a greater dispersion of solar energy in the environment causing an increase in temperature(Global Warming regardless of CO2). All the wood mass we see is related to the solar energy stored by the trees for many years. (I haven't considered the fruits of the trees etc, which in a year decompose and release solar energy and CO2 again) About it 1-Can there be a relationship between glaciations-forest decrease and forest increase-ice retreat(Glaciations cycles. Regardless of CO2)? 2-How much does it affect global warming?
  2. Surely pellet(solid fuel) from agricultural residues would replace a liquid carburant(diesel especially...) where it'd be possible to use it(in agricultural machines for example). Please note I read that one hectare of sugar cane produces 10 tonnes of dry bagasse and 10 of dry leaves left in the field(They aren't used to obtain sugar). It's an incredible resource to have solid fuels... It's energetically equivalent to around 8E3 litres of diesel without considering efficiency etc...
  3. It isn't a problem for agricultural vehicles... However solid ash represents only 3% as regards the combustion of wheat straw. Also corn stove pellets are interesting(especially in the U.S.). Infact corn stover left in the field after grain harvest represents an estimated yield of 8-10 tonnes of dry matter per hectare! In addition it seems to have a solid ash content about 5%. It doesn't seem a high value.
  4. I think some energy needs to be stored first of all. Energy can be stored by melting some salt...or by storing water under pressure in an insulated tank... For example I know that NaCl heat of fusion value is around 30 kj/mol ( 300 kwh/m3! ) so 1 m3 of NaCl can store 300 kwh of thermal energy. But it's a high fusion temp for straw combustion...
  5. I read that the most (however I'm not sure) efficient steam coal-fired train was 27% efficient in the past century 🙂 link: steam train thermal efficiency. (browse pages up to the Third Generation Steam(TGS)). So...I wonder if it's possible today to build biomass-fueled steam engines for bulky vehicles(agricultural etc...). Energy content of 1 liter of diesel is equivalent to 2.5 kg of wheat straw pellet(An example). BUT 1 liter of diesel costs around 1.5 u.s. dollars while 2.5 kg of wheat straw pellet is around 0.25 u.s. dollars. Problems can be: 1-wheat straw availability 2-power 3-volume I'll try to give some answers to these three questions 1-Wheat straw yield is about 3-6 tonnes per hectare. It's energetically equivalent to more than 1 tonne of diesel... Is there availability for agricultural vehicles and (maybe) trucks in general? We'he to consider efficiency also... 2-Vapour pressure can produce a great power. We know that Force=Pressure*Surface so if vapour pressure is 100 bar(In the water state diagram T is around 300°C) and surface is only 1 cmq we have F= 100 * (1e5 Pa) * (1e-4 mq) = 1e3 Newton! It's the force applied to low-middle power cars... I think it's no comments... What about efficiency? It would've to be around 27%... Comments? 3-Wheat straw pellet density is about 0.5 kg/dm3. So 5 'liters'(2.5 kg /(0.5 kg/dm3) ) of wheat straw pellet is energetically equivalent to 1 liter of diesel(So five to one about volume energy comparison). Would it be ok for bulky vehicles?
  6. In this istance dq >= e(electron charge) !...
  7. Is there an error in the calculation of the energy stored in the capacitors? The fact is that the charge doesn't tend to zero but to the electron charge...
  8. We need calculus to manipolate its properties and experience to be able to make a good job obviously! Another question about sodium is: -Can it power a submarine?... It seems it breathes underwater like a fish...
  9. I don't understand why God justice had to modify his judgement in Heaven. So, is new heaven referring to new planets? Example: a new Mars with delicious fruit and very good animals Obvious question: scientifically speaking, can a new Mars give us a great natural life?
  10. It's incredible what's happening in Italy!! The previous government stopped immigration. A political rebellion created a new government(two monthes before covid-19 beginning) and reopened immigration. But now they stopped immigration because of covid-19!! (It seems a real miracle!!!) Is God against muslim immigration in Europe? Is God against Bergoglio(the Pope) who prayed for immigration?
  11. There is no animal serum against hiv even if bovines(for example) produce Hiv antibodies...
  12. Probably it's possible to use wind energy to heat(using Faucault currents, so inconstant wind power isn't a problem) the salt. The very good news is that this molten salt has a great heat of fusion(around 250-300 kwh/m3) value so it can work even if wind is not constant.
  13. Fe --> more than 500 kwh/m3 (Tfus. 1538°C) Si --> more than 1e3 kwh/m3 (Tfus. 1414°C) NaCl --> more than 250 kwh/m3(Tfus. 801°C) Do you think it's possible to store a large quantity of (renewable)energy when a matter changes from a solid to a liquid?…
  14. Howere if plastic products are banned, their alternatives'd fill the market.
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