Generalized the use of neutron activation analysis(NAA)in the investigations of unique processes occurring in early stages of formations and evolution of bodies in solar system Out of them the formation of chondrules,...Generalized the use of neutron activation analysis(NAA)in the investigations of unique processes occurring in early stages of formations and evolution of bodies in solar system Out of them the formation of chondrules,emergence of ultra refractory inclusions in carbonaceous chondrites,formation of metallic and silicate phases of iron and stone meteorites,and formation of iron meteorites of different chemical groups Changes in regolite and lunar rock contents,differentiation in the upper mantle matter, identification of earthly meteoritic craters,transportation of cosmic(meteoritic)materials on to the Earth, investigations of unique events like Tunguska fall of the year 1908 and also ore formation studies and processes taking place on geochemical barrier type river-sea,ocean-atmosphere and so on Prospectives of NAA are pointed out展开更多
In the Universe, chemical reactions occur at very low temperature, very close to 0K. According to the standard Arrhenius mechanism, these reactions should occur with vanishingly small efficiency. However, cold planets...In the Universe, chemical reactions occur at very low temperature, very close to 0K. According to the standard Arrhenius mechanism, these reactions should occur with vanishingly small efficiency. However, cold planets of the solar system, such as Pluto, are covered by a crust composed of ammonia and methane, produced on earth only at very high temperature and pressure, in the presence of catalysts. This observation is incompatible with the predictions of Arrhenius kinetics. Here, we propose a general mechanism to explain the abundance of chemical reactions at very low temperature in the Universe. We postulate that the feedback between mechanical stress and chemical reaction provides, through fracture propagation, the energy necessary to overcome the activation barrier in the absence of thermal fluctuations. The notion described in this work can also be applied to other fields such as explosive-like solid phase transformations and catastrophical geotectonics phenomena (earthquakes).展开更多
文摘Generalized the use of neutron activation analysis(NAA)in the investigations of unique processes occurring in early stages of formations and evolution of bodies in solar system Out of them the formation of chondrules,emergence of ultra refractory inclusions in carbonaceous chondrites,formation of metallic and silicate phases of iron and stone meteorites,and formation of iron meteorites of different chemical groups Changes in regolite and lunar rock contents,differentiation in the upper mantle matter, identification of earthly meteoritic craters,transportation of cosmic(meteoritic)materials on to the Earth, investigations of unique events like Tunguska fall of the year 1908 and also ore formation studies and processes taking place on geochemical barrier type river-sea,ocean-atmosphere and so on Prospectives of NAA are pointed out
文摘In the Universe, chemical reactions occur at very low temperature, very close to 0K. According to the standard Arrhenius mechanism, these reactions should occur with vanishingly small efficiency. However, cold planets of the solar system, such as Pluto, are covered by a crust composed of ammonia and methane, produced on earth only at very high temperature and pressure, in the presence of catalysts. This observation is incompatible with the predictions of Arrhenius kinetics. Here, we propose a general mechanism to explain the abundance of chemical reactions at very low temperature in the Universe. We postulate that the feedback between mechanical stress and chemical reaction provides, through fracture propagation, the energy necessary to overcome the activation barrier in the absence of thermal fluctuations. The notion described in this work can also be applied to other fields such as explosive-like solid phase transformations and catastrophical geotectonics phenomena (earthquakes).
