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排序方式: 共有510条查询结果,搜索用时 15 毫秒
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Russian Engineering Research - Formulas are derived for the most important parameters of channel extrusion. 相似文献
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Victor Chabanenko Roman Puźniak Adam Nabiałek Sergei Vasiliev Vladimir Rusakov Loh Huanqian Ritta Szymczak Henryk Szymczak Jan Jun Janusz Karpiński Vitaly Finkel 《Journal of Low Temperature Physics》2003,130(3-4):175-191
We present a study of magneto-thermal instabilities in polycrystalline MgB2 superconductor, by magnetic hysteresis loop measurements and by investigations of magnetic flux dynamics with a miniature Hall probe. Temperature and magnetic field ranges where the flux jumps may be observed have been determined. On the basis of measurements of the magnetic flux dynamics, an average magnetic diffusivity describing the process of the flux jump is estimated. This parameter is compared with the thermal and magnetic diffusivities calculated on the basis of available data for thermal conductivity, heat capacity and resistivity. It is shown that the estimated value of the field of the first flux jump is influenced significantly by the field dependence of specific heat. In order to explain the observed phenomenon, the temperature reached by the sample during the flux jump at different magnetic fields is calculated. 相似文献
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The process of actuation is considered for the inertial element in the improved air-distributing system of pneumatic puncher whose dimensionless parameters are determined. 相似文献
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1 俄联邦防爆电气设备应用情况
传统上快速发展的工业部门如进行石油和天然气生产、运输以及加工处理的那些部门、石油化工行业,以及很多可能出现爆炸性环境的其他行业,在其一些场所中需要使用防爆电气设备。 相似文献
7.
Computational results are presented for the neutron characteristics of BIR and BIGR fast pulse reactors, specifically, cylindrical systems with a core consisting of an alloy of 90% or 36% enrichment uranium with 10 mass% molybdenum or a composite uranium–graphite material. The purpose of the calculations is to determine the possibility of increasing the size of the interior cavities in reactors without appreciably degrading the time parameters of the pulses.Reactor models with a metal core, which are best for further consideration, are systems with a disk core which have a cavity with a diameter up to 30 cm along the axis and a thickness-limited iron reflector. For reactors with uranium–graphite core, it is best to develop a new pulse reactor with an axial cavity which has a larger volume and is more accessible for sample placement than BIGR.An important problem of the calculations was to determine screen variants for a cavity which would prevent fuel overheating and at the same time be free of autocatalysis manifestations. 相似文献
8.
Vitaly Dubrovsky Danial Clapper Monali Ullal 《Computer Supported Cooperative Work (CSCW)》1995,4(1):33-49
An experiment was performed to test a distinct-window conferencing screen design as an electronic cue of social status differences in computer-mediated group decision-making. The screen design included one distinct window to symbolize high-status, and two nondistinct windows to symbolize low-status. The results indicated that the distinct-window screen design did produce status affects in groups of peers making decisions on judgmental problems. Randomly assigned occupants of the distinct window had greater influence on group decisions and member's attitudes than occupants of nondistinct windows.The authors would like to thank Shyam Kamadolli and Phaderm Nangsue, the programmers who developed the software used in this experiment. We would also like to thank the editor and our three anonymous reviewers for exceedingly helpful comments on an earlier draft of this article. 相似文献
9.
Cheng Xie Lei Xu Jinhui Peng Libo Zhang Xueqian Wang Jianying Deng Mickael Capron Vitaly Ordomsky 《Advanced functional materials》2023,33(14):2213782
Ti3C2 MXenes with different halogen modifications are prepared rapidly and efficiently by microwave molten salt method, and the MXene surface functional group modification is successfully achieved to address the problems of low purity, complex functional groups, and uncontrollable energy band structure of MXenes obtained by traditional liquid phase etching. Among them, the modification of the iodine (I) functional group onto the surface of Ti3C2 changes the energy band structure and band gap, resulting in easier photoexcitation and more photogenerated carriers. The increased Fermi energy is closer to the conduction band, the decreased surface work function weakens the electron confinement ability. The photogenerated carriers can migrate to the surface of the material more easily with extended lifetime, so the activity of the catalyst is improved. Further, for gaseous monomeric mercury (Hg0) photo-oxidative removal, Ti3C2-I2 exhibits 85.5% efficiency of Hg0 photo-oxidative removal under visible light. Based on the experimental characterization and density functional theory calculations, a mechanism for the photo-oxidative removal of Hg° from Ti3C2-I2 MXene is proposed, which provides a valuable strategy for studying Ti3C2 MXenes in the field of photocatalysis. 相似文献
10.
DNA‐Metalization: Synthesis and Properties of Novel Silver‐Containing DNA Molecules (Adv. Mater. 24/2016)
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