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排序方式: 共有251条查询结果,搜索用时 15 毫秒
1.
Crystallography Reports - The formation of β-Si3N4 for subsequent growth of AlGaN and GaN heterostructures of silicon wafers has been studied. It is established that the native oxide layer...  相似文献   
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Journal of Structural Chemistry - The crystal structures and biological properties of [N′-(2-oxidobenzylidene)-N-(prop-2-en-1-yl)-carbamohydrazonothioato(2-)](1,10-phenanthroline)copper...  相似文献   
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Russian Physics Journal - An important parameter of non-vacuum electron-beam cladding is the surface density of the input energy that depends on the beam current and the specimen travel speed. The...  相似文献   
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The performance of a cryogenically cooled double‐crystal silicon monochromator was studied under high‐heat‐load conditions with total absorbed powers and power densities ranging from 8 to 780 W and from 8 to 240 W mm?2, respectively. When the temperature of the first crystal is maintained close to the temperature of zero thermal expansion of silicon, the monochromator shows nearly ideal performance with a thermal slope error of 0.6 µrad. By tuning the size of the first slit, the regime of the ideal performance can be maintained over a wide range of heat loads, i.e. from power densities of 110 W mm?2 (at total absorbed power of 510 W) to 240 W mm?2 (at total absorbed power of 240 W).  相似文献   
6.
Magnetic properties of spatially ordered arrays of interacting nanofilaments have been studied by means of small-angle diffraction of polarized neutrons. Several diffraction maxima or rings that correspond to the scattering of the highly ordered structure of pores/filaments with hexagonal packing have been observed in neutron scattering intensity maps. The interference (nuclear-magnetic) and pure magnetic contributions to the scattering have been analyzed during the magnetic reversal of the nanofilament array in a field applied perpendicular to the nanofilament axis. The average magnetization and the interference contribution proportional to it increase with the field and are saturated at H = H S . The magnetic reversal process occurs almost without hysteresis. The intensity of the magnetic contribution has hysteresis behavior in the magnetic reversal process for both the positive and negative fields that form the field dependence of the intensity in a butterfly shape. It has been shown that this dependence is due to the magnetostatic interaction between the filaments in the field range of HH S . A theory for describing the magnetic properties of the arrays of interacting ferromagnetic nanofilaments in the magnetic field has been proposed.  相似文献   
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Chumakov  A.I.  Niesen  L.  Nagy  D.L.  Alp  E.E. 《Hyperfine Interactions》1999,123(1-4):427-454

Multilayer structures form a particular class of samples employed in nuclear resonant scattering of synchrotron radiation. Their specific properties lead to unusual energy and time characteristics of nuclear resonant scattering, which differ much from those of single crystals. The analysis of these distinctions is presented. Several approaches to achieve pure nuclear reflections with multilayers are discussed. Finally, we review the studies of multilayer structures with nuclear resonant scattering of synchrotron radiation.

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10.
A method has been developed for monitoring the dynamics of the number and viability of Dunaliella salina microalgae taking into account the spectral contribution from aggregates of metal particles tested as a toxic agent in a microplate assay system. The method is based on the in vivo determination of the chlorophyll content from the intensity of an absorption peak at 680 nm corrected for the nonselective extinction as calculated using the values of nearest local minima at 640 and 740 nm.  相似文献   
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