Pure Energy

History of energy

     The only source of energy that fueled our civilization until this century was solar energy stored as chemical energy through the process of photosynthesis, in regenerative sources (wood, water, wind) or fossil fuels (coal, oil, gas ) whose constant training is millions of years.
     I could say quite safely shovel, that energy aspect we were "slaves of the Sun" and it is no wonder that ancient peoples made the Sun one of the main gods of primitive religion.
     One major problem, whose solution depends on the development of our civilization, the issue returned to the plan of concerns in recent years is providing the energy needed to develop activities that condition the progressive development of the living standard of the population terrestrial globe. Cntitatea energy consumed by humanity increased primitive era so far, 2.5 million times. Obviously, such an increase can not be can not but lead to a problem of the energy needed for the future development of mankind .

Early atomic era

     As I said not long ago we were "slaves of the sun", but I step towards emancipation was made by physicist Becqerel on February 26. 1898 when he left a few photographic plates protected from light, near a uranium ore. developandu discovers them blackened, as if they have been exposed to light here, he concluded that uranium ore emits radiation unknown. Therefore French physicists Marie Curie and Pierre Curie have dedicated many years of research radioactive radiation. Together, these three scientists received the Nobel Prize for physics in 1903. Identification and study of these radiation begins to passionate researchers.
     So at the beginning of our century Ruthefort and his pupils, Chadwick Walton Cockfroft and investigated the properties of nuclei by artificially accelerated particles larger than the kinetic energy of the radiation emitted by radioactive substances.

Radioactivity

     Obtaining nuclear energy is conditioned by the presence of radioactive radiation. Radioactivity is presented as a phenomenon attended unstable nuclei that decay by emitting particles or radiation.            rays are helium nuclei, less penetrating. They can even be stopped by a sheet of paper. Rays            are electrons. They can be blocked by a sheet of aluminum.         rays  are pure energy. They can be blocked by the lead. We direct this type of radiation and on other atoms, as we bombard a target with missiles. Radioactive particles are designed to power the target nuclei. They "inflate" the mass of these nuclei or break them into fragments. Challenging these radiations phisics have the opportunity to study the structure of atoms in plants called accelerators. When bombarded with alpha rays which some atoms are radioactive. This phenomenon is called artificial radioactivity.

Nuclear energy

     Fusion underlies obtain nuclear energy. This process consists of absorption of a neutron by an atomic nucleus large as that of uranium, which will become unstable. He will break into several fragments, releasing great heat, which strongly accelareza fragments that reach very high speeds. Due to their high speed, these fragments following fission can enter in turn into other atoms, which cause other fissions.

Uses of Nuclear Energy

Power generation in thermal power plants

     In 1990 there were 435 nuclear power plants operating acoperind1% of global energy.
In a nuclear reactor to obtain heat through radioactive decay of uranium-235 atoms. This is used to produce steam that moves the rotor turbines, generating electricitate.U-235 is a relatively rare isotope of uranium, accounting for only 7% of the total amount of uranium available. The rest is U-238 isotope. An isotope of an element is a form other isotopes chemically identical but different atomic mass. Like fossil fuels, U-235 will not last forever. There is a certain type of reactor, reactor called "growth" U-238 which turns into another radioactive element, plutonium-239. Pu-239 can be used to generate heat. So far only six countries have constructed experimental plants. Of these, nuclear reactor Phenix has the highest success. If this type of reactoarear become common, global reserves of uranium would reach thousands of years

Pros and cons of nuclear energy

     Nuclear energy has many advantages. Is economic: a ton of U-235 produces more energy than insight by 12 million barrels of oil. Eate clean during use and does not pollute the atmosphere. Unfortunately there are some drawbacks. Nuclear power plants are very expensive. Produce radioactive waste that must be stored for hundreds of years before becoming harmless. A nuclear accident like the one that occurred in1986 at the Chernobyl nuclear plant in Ukraine, can contaminate large areas and can cause illness or death of hundreds of people.
     Researches are heading to discover new inexhaustible sources of energy. Some of them are already used.
Wind power (wind) afost used for centuries to propel ships and windmills drive. Modern wind turbines have been built can generate electricity. Only in California there are 15,000 such turbines. U.S. scientists calculated that the entire amount of energy could be generated by wind. Solar energy is the sun's heat on. Solar collectors in the form of panels can cover the energy needs of a house. Fuel cells made from silicon are used to produce energy in outer space.

The atomic bomb

      In 1945, the principle of nuclear fission afost device used to an entirely different nature: the atomic bomb. In this case, the fission reaction is slow, it develops and takes place with huge energy release. The potential of this weapon was realized when on August 6, was released on Hiroshima, causing 150,000 casualties and later on Nagasaki August PE10, recording and there tens of thousands of deaths.

Did you know ...

... a grain of uranium 238 can produce the same heat produced by the combustion of coal or 1 to 2.7 tons, 9 tons of oil?

 ...uranium and thorium reserves are sufficient to ensure future energy consumption over a period of 7-8 hundred years, if fast reactors use uranium 238 in reproduction?

... if we could achieve the fusion reaction of deuterium with deuterium, then a cubic meter of water will have a content equivalent to 300 tons of coal or 1300 barrels of petrol. Energy reserves, in this case, are so great that no we have problems over a period of several thousand years?