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排序方式: 共有467条查询结果,搜索用时 15 毫秒
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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
3.
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
4.
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
5.
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
6.
DNA‐Metalization: Synthesis and Properties of Novel Silver‐Containing DNA Molecules (Adv. Mater. 24/2016) 下载免费PDF全文
7.
M.?I.?ZaretskayaEmail author B.?V.?Skvortsov 《Journal of Computer and Systems Sciences International》2017,56(2):259-267
Theoretical bases for controlling the application of coatings to the inner surface of pipes and other hollow products are considered based on the stabilization of the velocity of the coating material in the product cavity taking into account temperature and viscosity. The device makes it possible to automatically compensate for the variation in the coating thickness depending on temperature taking into account the characteristics of the used control equipment. The dependence of the coating thickness on temperature and material velocity is described. The system that implements the proposed method in the MATLAB + SIMULINK shell is simulated. The optimal values of the system gain and level sensor sensitivity that minimize the dynamic error of the control system are determined. 相似文献
8.
Thermal conditions in an aluminum metallization stripe deposited onto a single crystal silicon substrate have been studied during the passage of single rectangular electric pulse with a current density of j < 8 × 1010 A/m2 and a duration of τ = 100–1000 μs. Based on the results of this analysis, a method of diagnostics of the state of metallization contact systems and determination of the conditions of their safe operation is proposed. 相似文献
9.
Elena Bozhevolnaya Anders Lyckegaard Ole. T. Thomsen Vitaly Skvortsov 《Composites Part B》2004,35(6-8):619-627
The paper considers local bending effects induced in the vicinity of inserts in sandwich panels. Such local bending effects are associated with an increase of bending stresses in the sandwich faces and normal and shear stresses in the sandwich core. An earlier developed analytic model [Proceedings of the Sixth International Conference on Sandwich Structures (ICSS-6) (2002) 551] is adapted for the case of a sandwich panel with circular insert, with elastic properties differing from those of the core. The locally induced stresses in the faces and core due to presence of the insert are expressed via simple analytic relations (and charts) enabling an estimation of these local stresses. Finite element analysis is employed to demonstrate the applicability of the analytic model, and a good correspondence between the numerical and the analytical data is found. A study case related to marine applications, namely a circular insert in a sandwich deck panel used for mounting of a rigging fixture, is considered, and optimization of an existing design is carried out. 相似文献
10.