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41.
A new method is proposed for small baseline spectral analysis of discrete multibeam fields, which is composed of a combination of proximity beam selection and a subsequent phase determination of beam position by the least squares method. The feasibility of the method is corroborated by experimental data.Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 82–86, June, 1995.  相似文献   
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Results of experimental investigations on radar sensing of inhomogeneous media and objects with the use of both superbroadband (from 0.5 to 17 GHz) multifrequency scanning and supershort nanosecond and subnanosecond radar pulses are considered. It is demonstrated that addition of angular and spatial scanning and subsequent synthesis of a large aperture allow a three-dimensional tomography of low-contrast inhomogeneities to be realized with a spatial resolution of about 1 cm. Examples are presented that confirm a high efficiency of the method for contactless tomography of the forest structure and detection and visualization of infantry mines below a rough sand surface. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 20–25, September, 2006.  相似文献   
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In this paper we find conditions that guarantee that irregular boundary value problems for elliptic differential-operator equations of the second order in an interval are coercive with a defect and fredholm; compactness of a resolvent and estimations by spectral parameter; completeness of root functions. We apply this result to find some algebraic conditions that guarantee that irregular boundary value problems for elliptic partial differential equations of the second order in cylindrical domains have the same properties. Apparently this is the first paper where the regularity of an elliptic boundary value problem is not satisfied on a manifold of the dimension equal to the dimension of the boundary. Nevertheless, the problem is fredholm and the resolvent is compact. It is interesting to note that the considered boundary value problems for elliptic equations in a cylinder being with separating variables are noncoercive. I wish to thank the referee whose comments helped me improve the style of the paper. Supported in part by the Israel Ministry of Science and Technology and the Israel-France Rashi Foundation.  相似文献   
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Summary 1. It has been established that the method of isolating ribosomes by precipitation with ethanol in the presence of Mg2+ can be used in the isolation of ribosomes from the seeds of other plants. The isolated 5S rRNAs have the same electrophoretic mobility, while the 5S rRNAs from plants differ sharply from the 5S rRNAs of yeast in electrophoretic mobility which is apparently due to differences in their secondary and tertiary structures.2. In the sprouting of cotton seeds, the amount of total rRNAs first increases (two-day shoots) and then falls (seven-day shoots).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 56–59, January–February, 1979.  相似文献   
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The thermal analysis of acetate clusters of general formula [Fe 2 III MIIO(CH3COO)6(H2O)3]·2H2O, with M=Mn, Fe, Co or Ni, was performed in dynamic and quasi-isothermal regimes. The thermal decompositions of these compounds proceed in the interval 40–310° and consist of two endothermic and three exothermic stages. Dependence on the nature of the transition metal M is evidenced most explicitly in the parameters of the second stage, proceeding in the interval 103–170°. For this stage the sequences of thermodynamic stability and kinetic stability were established. The effect of the nature of the metal on the thermodynamic and kinetic parameters of the thermal decomposition processes involving the heteronuclear acetates was analyzed. Mechanisms for the first two stages of thermal decomposition are suggested.  相似文献   
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We investigate a boundary-functional problem with transmission conditions for ordinary differential-operator equation in Sobolev spaces with a weight. We prove an isomorphism, coerciveness with respect to the spectral parameter, completeness and Abel basis of a system of root functions of the problem. Obtained results in the article are new even in case of Sobolev spaces without the weight.  相似文献   
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