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781.
782.
热压法(Hot embossing)是一种快速复制微流控芯片的技术.它是生产高质量、高精度聚合物材料微流体芯片的一种方法. 相似文献
783.
本文研究MAR-M247镍基超合金表面经铝化涂层或白金铝化涂层处理后,其热腐蚀效应对腐蚀速率与显微组织之影响,并藉试片质量增加量的变化评估抗热腐蚀的能力.铝化涂层之主要组成为-βN iA l相,而白金铝化涂层表面的主要组成为PtA l2相,利用盐喷覆法将Na2SO4被覆在试片表面,置于热处理炉中观测其热腐蚀性.实验得知,铝化涂层和白金铝化涂层均可明显抑制MAR-M247的热腐蚀,且后者之效果更明显,此两种涂层在910℃之Na2SO4环境中的抗蚀性均较MAR-M247合金为佳. 相似文献
784.
J. A. Chakera M. Raghuramaiah P. A. Naik P. D. Gupta V. K. Chevokin 《Optics & Laser Technology》2001,33(6)
A simple system for an on-line temporal characterization of an X-ray streak camera is described. Multiple UV-transmitting fiber optic channels with known relative time delays facilitate measurements of sweep speed in addition to providing a fiducial signal. Results of measurements on variation of sweep speed across the output screen of an in-house developed X-ray streak camera of an average sweep speed of 24.5 ps/mm and a temporal resolution of 7.5 ps are presented. 相似文献
785.
A midrapidity zone formed in heavy-ion collisions has been investigated through special selections of light particles and
intermediate mass fragments detected in the reaction 35Cl on 12C at 43 MeV/nucleon and the reactions 58Ni on 12C, 24Mg, and 197Au at 34.5 MeV/nucleon, and of neutron energy spectra measured in the reaction 35Cl on natTa. Properties of the observables have been examined to characterize the neck-like structure formed between the two reaction
partners.
For the HERACLES collaboration. 相似文献
786.
EvangelosChaliasos 《理论物理通讯》2003,40(1):101-102
After finding the really self-consistent electromagnetic equations for a plasma, we proceed in a similar fashion to find how the magnetohydrodynamical equations have to be modified accordingly. Substantially this is done by replacing the “Lorentz“ force equation by the correct (in our case) force equation. Formally we have to use the vector potential instead of the magnetic field intensity. The appearance of the formulae presented is the one of classical vector analysis. We thus find a set of eight equations in eight unknowns, as previously known concerning the traditional MHD equations. 相似文献
787.
788.
The generation and processing of fine powders in thermal plasmas has attracted increasing interest over the past years, precipitated by a growing awareness that conservation of materials is no longer an option but rather a necessity. Plasmaspheroidization, densification, fuming, metallurgical reduction, and the production of refractory oxides, carbides, nitrides, and borides in thermal plasmas are fast developing technologies which, in some cases, have already reached industrial production scale.In this survey, pertinent literature (198 references) will be reviewed with emphasis on basic studies in this field, reported over the past 20 years. The first part of this review covers powder handling, quenching characteristics, nucleation and growth, and modeling of plasma-particle interactions. The second part is concerned with plasma furnaces for the production of fine particles, including RF induction plasmas, DC anode furnaces, DC plasma jets, DC transferred arcs, cathode pump fed arcs, hybrid induction-DC plasmas, and three-phase AC furnaces. 相似文献
789.
790.