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51.
52.
航天器地面供配电设备接口设计技术 总被引:1,自引:1,他引:1
李立 《计算机测量与控制》2003,11(6):447-450
航天器地面供配电设备必须要确保供电控制的可靠和测量的准确。概述了该设备的基本组成和功能,对设备和航天器之间的控制信息、状态信息和测量信息的接口设计技术作了较详细地论述,并且结合有代表性的示例给出了参考电路图和说明。 相似文献
53.
Thomas R. Hammant 《Cryptologia》2013,37(1):50-60
The importance of radio communications, both in controlling military forces and for purposes of intelligence collection, was recognized from the beginning by the new Soviet leaders in Russia. By January 1919, a radio intelligence service had been established in the Red Army, although shortages of equipment and comint personnel limited its operations during the civil war. Both sides in the civil war suffered from poor communications security. 相似文献
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AbstractWe have characterized the structure and electrical properties of p-type nanocrystalline silicon films prepared by radio-frequency plasma-enhanced chemical vapor deposition and explored optimization methods of such layers for potential applications in thin-film solar cells. Particular attention was paid to the characterization of very thin (~20 nm) films. The cross-sectional morphology of the layers was studied by fitting the ellipsometry spectra using a multilayer model. The results suggest that the crystallization process in a high-pressure growth regime is mostly realized through a subsurface mechanism in the absence of the incubation layer at the substrate-film interface. Hydrogen plasma treatment of a 22-nm-thick film improved its electrical properties (conductivity increased more than ten times) owing to hydrogen insertion and Si structure rearrangements throughout the entire thickness of the film. 相似文献
56.
E. Guziewicz M. Godlewski K. Kopalko E. Dynowska M.M. Godlewski 《Thin solid films》2004,446(2):172-177
Thin films of sphalerite-type ZnSe were grown by atomic layer deposition (ALD) from elemental Zn and Se precursors. These films, grown on various substrates, show bright blue ‘edge’ emission accompanied by donor-acceptor pair emissions in the blue, green and red spectral regions. Red, green and blue emissions mixed together give a white color, with a color temperature between 2400 and 4500 K depending on a layer thickness and temperature. ZnSe grown by ALD is in consequence a promising material for the fabrication of semiconductor-based white light emitting thin film electroluminescence displays. 相似文献
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采用离子束溅射镀膜装置制备了一种新的材料组合Si/C多层膜 ,用于 30 4nm波段的正入射多层膜反射镜。并用软X射线反射率计测得其反射比最大值为 0 14。有效地抑制了 15 0nm处的二级衍射峰。 相似文献
59.
Thin films of CaCO3 (calcite) have been grown with the atomic layer chemical vapour deposition (ALCVD) technique, using Ca(thd)2 (Hthd=2,2,6,6-tetramethylheptan-3,5-dione), CO2, and ozone as precursors. Pulse parameters for the ALCVD-type growth are found and self-limiting reaction conditions are established between 200 and 400 °C. Calcium carbonate films have been deposited on soda-lime glass, Si(100), -Al2O3(001), -Al2O3(012), -SiO2(001), and MgO(100) substrates. The observed textures were: in-plane oriented films with [100](001)CaCO3 [100](001)Al2O3 and [100](001)CaCO3[110](001)Al2O3 on -Al2O3(001), amorphous films on -Al2O3(012) when grown at 250 °C, and columnar oriented films on soda-lime glass, Si(001), -SiO2(001), and MgO(100) substrates with (00l) and (104) parallel to the substrate plane at 250 and 350 °C, respectively. The film topography was studied by atomic force microscopy and AC impedance characteristics were measured on as-deposited films at room temperature. The films were found to be insulating with a dielectric constant (r) typically approximately 8. Thin films of CaO were obtained by heat treatment of the carbonate films at 670 °C in a CO2-free atmosphere, but the thermal decomposition led to a significant increase in surface roughness. 相似文献
60.
Makoto KUWABARA 《材料科学技术学报》2005,21(6):887-890
1. IntroductionZinc oxide films have been attracting more and moreattention because of their high diffractive index, low resis-tance, and photoluminescence properties, and are beingused as transparent electrodes, basis material for opti-cal wave guide devices, gas sensors and so on. Manymethods have been developed to prepare ZnO films, suchas chemical vapor deposition[1], reactive evaporation[2],pulsed laser ablation[3], sputtering[4], spray pyrolysis[5]and hydrothermal method[6]. There are a… 相似文献