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71.
本文对激光结晶a-Si∶H SOI结构砷注入和快速退火行为作了研究.a-Si∶H激光结晶有Lp-LCR,OD,FCR-2,FCR-1四个结晶区.用剖面电镜观察了结晶区的结构.扩展电阻测量表明Lp-LCR区中有两种扩散机制,即杂质在晶粒体内扩散和沿缺陷扩散.OD区中有三种扩散形式,除有上述两种以外,还有沿缺陷的扩散.首次比较了沿晶界和缺陷的扩散速度. 相似文献
72.
U. Amato G. Amodeo V. Brandi V. Cuomo D. Ruggi C. Serio V. Silvestrini G. C. Tosato 《国际能源研究杂志》1985,9(1):33-51
In Italy solar thermal energy and energy from biogas are two possible means of reducing dependence on energy imports. Using a multiperiod LP model (MARKAL) the authors assessed the likely potential of both technologies under various circumstances. The study covered the period 1980–2005, in five segments of five years. It focused only on the subsystem of the energy end-uses which can be substituted for by solar thermal and biogas technologies. The overall non-renewable sources which can be saved in 20 years by these technologies total 450 PJ (1 PJ = 101 5 J) if the fuel prices rise at 0 per cent average annual, 1450 PJ if the fuel prices rise at 4.2 per cent average annual, 1860 PJ if the fuel prices rise at 7.2 per cent average annual and 3780 PJ if the fuel prices rise at 15 per cent average annual. However the most competitive technologies appear to be solar water heaters used mainly in the private and commercial sectors and biogas systems used mainly in the agricultural sector. The study was carried out by APRE under ENEA (formerly CNEN) contract and was intended to serve as an analytical basis for establishing an overall development and demonstration strategy for end-use renewable technologies in Italy. 相似文献
73.
I. N. Ishchuk 《Measurement Techniques》2007,50(10):1081-1086
A three-dimensional solution of the direct problem of heat conduction when a linear pulsed heat source acts in the plane of
contact of two semibounded bodies is presented. The solution is obtained by the method of finite differences. An example of
the modeling is considered.
__________
Translated from Izmeritel’naya Tekhnika, No. 10, pp. 42–45, October, 2007. 相似文献
74.
采用化学共沉淀法作为钴蓝颜料的制备方法,探讨了主要工艺因素对制备钴蓝颜料性能的影响,对制备的样品进行了测试与表征。结果表明:Co2+和Al3+物质的量比为1∶2.5时,制备的钴蓝样品颜色饱和度与明度最高,沉淀剂为尿素时制得的样品的粒度最小,粒度分布比较均匀。前驱体的洗涤过程采取水洗加醇洗的方法可有效减少样品的硬团聚现象,且前驱体的最佳煅烧温度为950℃左右。 相似文献
75.
Dario Pasini Luigi Garlaschelli Elza Bontempi Laura E. Depero 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(5):367-378
The synthesis of a series of polymers and cyclopolymers bearing crown ethers of differing structure and affinities towards primary ammonium ions is discussed. These polymers have been tested in their efficiency to form structurally homogeneous thin films when blended with an amphiphilic C60 compound containing a primary ammonium ion functional group. The X-ray reflectivity characterization of the films revealed that the polymer bearing the crown ether with the least affinity for primary ammonium ions, but having the highest degree of polymerization, is the most effective in forming structurally homogeneous thin films. 相似文献
76.
基于高抗热震性能的陶瓷刀具材料的微观结构设计 总被引:1,自引:0,他引:1
本文以现有的抗热震断裂和抗热震损伤的评价理论为基础,通过对材料中微裂纹的长度进行预测,从而实现了对陶瓷刀具材料的抗热震性能的微观结构设计。根据此理论对现有材料的抗热震性能的进行预测,预测结果与实际的测量结果相符,验证了该理论的正确性。 相似文献
77.
A. J. Slifka B. J. Filla 《Journal of research of the National Institute of Standards and Technology》2003,108(2):147-150
An industrial ceramic thermal-barrier coating designated PWA 266, processed by electron-beam physical-vapor deposition, was measured using a steady-state thermal conductivity technique. The thermal conductivity of the mass fraction 7 % yttria-stabilized zirconia coating was measured from 100 °C to 900 °C. Measurements on three thicknesses of coatings, 170 μm, 350 μm, and 510 μm resulted in thermal conductivity in the range from 1.5 W/(m·K) to 1.7 W/(m·K) with a combined relative standard uncertainty of 20 %. The thermal conductivity is not significantly dependent on temperature. 相似文献
78.
79.
A. J. Slifka T. Hall E. S. Boltz 《Journal of research of the National Institute of Standards and Technology》2003,108(2):151-156
A simple measurement system is described for evaluating damage to graphite-epoxy panels, such as those used in high-performance aircraft. The system uses a heating laser and infrared imaging system to measure thermal performance. Thermal conductivity or diffusivity is a sensitive indicator of damage in materials, allowing this thermal measurement to show various degrees of damage in graphite-epoxy composites. Our measurements track well with heat-flux damage to graphite epoxy panels. This measurement system, including analysis software, could easily be used in the field, such as on the deck of an aircraft carrier or at remote air strips. 相似文献
80.