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991.
Measurements of thermal conduction in tokamaks parallel to the magnetic field were up to 20 times less than the classical
values. This was explained by the quantum correction of the collision frequency of electrons with ions. This stowing effect
of heat is applied to re-evaluate the ignition threshold for the energy flux density E* for the ignition of solid state density
deuterium tritium using nonlinear (ponderomotive) laser force driven space charge neutral plasma blocks. 相似文献
992.
G. Pintsuk J. Compan T. Koppitz J. Linke A.T. Peacock D. Pitzer M. Rdig S. Wikman 《Fusion Engineering and Design》2009,84(7-11):1525-1530
Carbon fiber composites (CFCs) are the first choice as plasma facing materials for the strike points of divertor targets for future nuclear fusion devices like WENDELSTEIN 7-X and ITER. For the application in these facilities several potential European 3D-CFCs were compared and qualified: (1) four material batches of NB31 produced by Snecma Propulsion Solide (SNECMA); (2) NB41, SNECMA, the upgraded version of NB31; (3) N31, SNECMA, which is densified by chemical vapor infiltration (CVI) instead of a final liquid pitch infiltration characteristic for NB31; (4) a new developmental 3D-CFC produced by DUNLOP.The characterization of the composites is comprised of thermo-physical measurements and tensile tests. The results are correlated to density and microstructure and summarized as follows: (1) NB41 provides the highest thermal conductivity in the ex-pitch direction of 375 W/(m K) at room temperature; (2) all material grades are, due to their heterogeneity, characterized by a relatively large scatter of mechanical properties; (3) the different densification process for N31 in comparison to NB31 has no influence on the material properties; (4) NB41 provides in all three directions a comparably high tensile strength with an average in the ex-pitch direction of 220 MPa; (5) the 3D-CFC from DUNLOP is comparable to NB41 but yet does not meet the specifications in the needling direction. 相似文献
993.
M. Eid M.A. Abdel-Ghaffar 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(1):91-98
The highly swelling Poly (acrylamide/maleic acid/gelatin) P(AAm/MA/G) hydrogels were prepared by gamma-irradiation at low dose rate (0.94 kGy/h) and moderate dose rate (3.84 kGy/h). The hydrogels were confirmed by FTIR. The effect of copolymer composition, dose and dose rate on the swelling behaviour was discussed. Increasing of MA content and G in the initial mixture leads to an increase in the amount of MA and G in the gel system and decrease in the gelation %. The swelling behaviours of the hydrogel prepared at moderate dose rate increased with increasing MA mole content in the gel system but, there is no systematic dependence of swelling on MA content was observed for the hydrogels obtained at low dose rate. Pore structure of the hydrogels was monitored by using scanning electron microscopy. Thermogravimetric analysis (TGA) and the rate of the thermal decomposition of P(AAm/MA/G) hydrogels has been evaluated to give a better understanding of the thermal stability of polymers, The X-ray data of P(AAm/MA/G) hydrogels was discussed to investigate some features namely the degree of ordering and crystallite size. 相似文献
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对三相单管有源功率因数校正器的运行原理进行了分析,并在此基础上给出了工作在电流临界连续模式下的变换器控制方案.根据运行原理和控制方案建立主电路和控制电路的仿真模型,对仿真验结与实验结果进行了对比分析,实验结果证明了该控制方案的可行性. 相似文献
998.
菱铁矿的选矿开发研究与发展前景 总被引:26,自引:14,他引:12
简述了当前我国铁矿资源巨大需求市场条件下,开发菱铁矿资源的必要性,着重论述了开发菱铁矿资源采用的焙烧一磁选、强磁选、浮选、预还原及相关技术的研究现状,介绍了菱铁矿分离技术的最新研究与发展前景。 相似文献
999.
20世纪以来,伴随着信息技术和网络经济的飞速发展,电子货币应运而生,成为当今货币发展的最新形式.针对电子货币对货币政策传导机制的影响,本文从理论角度对其进行系统的阐述,并提出相应的观点. 相似文献
1000.