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311.
The kinetics of electronic processes in vidicon phototargets based on semiconductor-insulator structures with a narrow-gap semiconductor is considered taking into account charge drain in the insulator layer and relaxation of the nonequilibrium depletion region in the semiconductor layer. The integration time, threshold sensitivity, and resolution at various intensities of incident radiation are estimated. 相似文献
312.
Heretakis I.I. Papakanellos P.J. Capsalis C.N. 《Antennas and Propagation, IEEE Transactions on》2005,53(3):938-947
A genetically optimized technique that fully automates the potentially laborious allocation of the auxiliary monopoles for the method of auxiliary sources (MAS) is presented for the problem of electromagnetic (EM) scattering by isotropic dielectric cylinders with various cross sections. The proposed technique uses as input information not only the geometry of the scatterer but also the exciting field and the material properties of the cylinders are implicitly taking part in the optimization procedure. The resulting auxiliary surfaces, where the simulating monopoles are situated, are appropriately adapted to the original boundary surface and the MAS modeling is greatly facilitated. In addition, certain considerations are taken into account in order to avoid undesirable numerical dependencies between the fictitious monopoles. Finally, the accuracy of the numerical method combined with overdetermined systems of equations is examined for isotropic cylinders of various geometries and dielectric characteristics. 相似文献
313.
The effect of treatment with a zirconyl nitrate aqueous solution on the structure; the hydroxyl-layer constitution; and the adsorptive, acid, and catalytic properties of dealuminated zeolite Y was studied. The zeolite was prepared by boiling NH4Y in an ethylenediaminetetraacetic acid disodium salt solution followed by ion exchange with ammonium chloride and calcination in a 100% steam flow at 750°C. X-ray diffraction, IR spectroscopy, and DTA data show the formation of an ultrastable form of zeolite Y. The incorporation of zirconium in zeolite led to an increase in the proportion of strong acid sites, thus raising the yield of cracking products during n-hexane conversion tested on platinum-containing catalyst samples. 相似文献
314.
A new diffuser capable of scattering light in one direction (one-dimensional diffuser) has been developed and experimentally
tested. The diffuser is formed in a thick layer of dichromated gelatin. The scattering indicatrices of the diffuser measured
in two mutually perpendicular directions are presented. It is demonstrated that the indicatrix width in one direction is significantly
greater than that in the perpendicular direc-tion. However, no zero-order diffraction has been observed. The proposed one-dimensional
diffuser exhibits close scattering indicatrices for reading at a wavelength of 0.44 and 0.63 μm. 相似文献
315.
A method of measuring static and pulsed pressures using electrically conducting rubber sensors is proposed. The method is
based on a change in the volume resistivity of a filled rubber under the action of external pressure. The pressure-induced
change in resistance of the rubber sensor is proportional to the applied pressure and can be measured by a bridge circuit.
Using this method, it is possible to evaluate the degree of homogeneity of the pressure distribution over a solid surface.
This is achieved by distributing rubber sensors over the given surface. 相似文献
316.
Conclusions The chemical mutagenesis method is recommended for use in local purification installations for cleaning up of caprolactam-containing wastewater.Use of this method permits one to carry out a biochemical clean-up of wastewater having a caprolactam content up to 600 mg/liter while increasing the oxidative power of the aeration tank by a factor of two.Translated from Khimicheskie Volokna, No. 6, p. 46, November–December, 1985. 相似文献
317.
Research suggests that predictable electric shocks produce less stress than unpredictable shocks. In this experiment, predictability was manipulated by using fixed-time (FT, predictable) and variable-time (VT, unpredictable) schedules of shock delivery. Rats receiving 3-mA, 1-s electric shocks on a FT 45-s schedule developed less gastric pathology than another group that was administered identical shocks on a VT 45-s schedule. It is argued that this finding represents a more subtle effect of predictability than has been obtained heretofore. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
318.
A novel moment-based m parameter estimator using noisy channel samples is derived. This estimator is simpler than known estimators. Numerical results are presented to demonstrate that, under some practical fading conditions, it outperforms previous estimators. 相似文献
319.
Changes in the phase compositions and microstructures of magnesia-partially-stabilized zirconia (Mg-PSZ) were studied in water at 80–300 °C, 1 m HCl solutions at 80–140 °C and 1 m CH3COOH-CH3COONa buffer solutions at pH 3 and 80–140 °C for 10–40 days. The tetragonal to monoclinic phase transformation and the degradation of the fracture strength occurred in water above 200 °C. On the other hand, although no noticeable tetragonal to monoclinic phase transformation proceeded in 1 m HCl solutions and 1 m CH3COOH-CH3-COONa buffer solutions at pH 3 below 140 °C, the fracture strength of Mg-PSZ greatly degraded. The dissolution of Mg2+ ion was observed in water above 200 °C and in 1 m HCl solutions above 80 °C. 相似文献
320.
N. V. Vostokov Yu. N. Drozdov Z. F. Krasil’nik O. A. Kuznetsov A. V. Novikov V. A. Perevoshchikov M. V. Shaleev 《Russian Microelectronics》2005,34(4):203-209
The results are presented of the fabrication of strain-relaxed graded Si1 − x
Gex/Si(001) buffer layers with a maximum Ge fraction of about 0.25 that have a low density of threading dislocations (<106 cm−2) and low surface roughness. The buffer layers are grown by atmospheric-pressure hydride CVD. It is found that chemical mechanical polishing can reduce their surface roughness to a level comparable with that of the original Si(001) substrates. It is shown that the polished buffer layers can serve as substrates for MBE-grown SiGe/Si heterostructures.__________Translated from Mikroelektronika, Vol. 34, No. 4, 2005, pp. 243–250.Original Russian Text Copyright © 2005 by Vostokov, Drozdov, Krasil’nik, Kuznetsov, Novikov, Perevoshchikov, Shaleev. 相似文献