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1.
A physical program of irradiation of emulsions in beams of relativistic nuclei named the BECQUEREL Project is reviewed. It is destined to study in detail the processes of relativistic fragmentation of light radioactive and stable nuclei. The expected results would make it possible to answer some topical questions concerning the cluster structure of light nuclei. Owing to the best spatial resolution, the nuclear emulsions would enable one to obtain unique and evident results. The most important irradiations will be performed in the secondary beams of He, Be, B, C, and N radioactive nuclei formed on the basis of JINR Nuclotron beams of stable nuclei. We present results on the charged state topology of relativistic fragmentation of the 10B nucleus at low energy-momentum transfers as the first step of the research.  相似文献   
2.
New results concerning the topology of the fragmentation of relativistic nuclei 7Li and 10B are presented. A program is proposed for studying the cluster structure of stable and radioactive nuclei. The use of emulsions in the investigation of nuclear clustering in the fragmentation of light nuclei at energies are in excess of 1 GeV per nucleon is discussed.  相似文献   
3.
The iron containing corrosion products from water heat-carrier and deposits of the second circuit of the nuclear power plant were investigated by means of absorption Mössbauer spectroscopy. The nonstoichiometric magnetite and paramagnetic (superparamagnetic) iron oxide particles were found to be the main corrosion products. The fraction of the magnetically ordered phase varied in the range 0–100% depending on the location in the second circuit.  相似文献   
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One considers a weighted Voronoi tessellation generated by a system of n Poisson fields of centroids. One investigates the composition and the boundary field of this structure. It is proved that the boundary field intensity between grains of types i and j (1ijn) is equal to where pi is the volume part, i>0 is the weight (for the comparison of distances) of the i-th component, c is a scaling factor. One obtains formulas for the boundary field intensities in plane and linear sections of the structure: . Estimators for the parameters pi and i from the observation of the linear section are proposed.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 153, pp. 160–172, 1986.  相似文献   
6.
Structures of six cyclic polysulfides, previously unknown as organic environmental pollutants, were analyzed from a sediment sample from the Eastern Gulf of Finland. The determinations were done by gas chromatography connected to mass spectrometry. High resolution (HRMS) measurements of the isotopic composition of four compounds could be done to confirm their molecular formulae. Total low resolution (LRMS) spectra were used to elucidate structures of all six compounds by thermochemical approach, application of fragmentation rules and by ICLU simulation of the spectra. The compounds were deduced to be (in the order of GC- retention) 1,2,4-trithiacycloheptane, tetrathiacyclopentane, 1,2,4,5-tetrathia-cyclohexane, 1,2,3,4- tetrathiacycloheptane, 1,2,3,4-tetrathiacyclohexane and 1,2,4,6-tetrathiacyclooctane.  相似文献   
7.
Micelle formation in a cetyltrimethylammonium bromide-poly(ethylene glycol)-600 monolaurate-chloroform system in the absence and presence of hydroxybenzylated polyethylenimines (PEI) was studied by dielcometric titration, NMR self-diffusion, light scattering, and kinetic methods. A catalytic effect of mixed micelles on the reaction of 4-nitrophenylbis(chloromethyl)phosphinate with PEI was shown. The catalytic effect depends on the degree of substitution of PEI and composition of a surfactant mixture. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1359–1365, August, 2006.  相似文献   
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9.
It has been established that physically adsorbed and chemisorbed atoms take part in the recombination of H-atoms on ZnS surface.
- ZnS .
  相似文献   
10.
1.  Up to a certain point (55%), decationization of NaY zeolites reduces the activity of the zeolites in catalyzing the hydrogenation of 2-methyl-2-butene. Further decationization had no effect on the yield of saturated hydrocarbons.
2.  Plotted as a function of the cation's electrostatic potential, the activity of MNaY zeolites in catalyzing the hydrogenation of 2-methyl-2-butene passes through a maximum. Minimum activity was observed with the NdNaY zeolite.
3.  Experiments in an atmosphere of helium showed that saturated hydrocarbons, resulting from hydrogen redistribution, are frequently formed in the course of reactions on decationized and polyvalent cationic forms of the Y zeolite.
  相似文献   
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