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11.
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Hiroyuki Miki Takanori Takeno Toshiyuki Takagi Alexei Bozhko Mikhail Shupegin Hideya Onodera Takao Komiyama Takashi Aoyama 《Diamond and Related Materials》2006,15(11-12):1898
Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon. 相似文献
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An integrated process based on simultaneous solid-liquid extraction and liquid membrane separation is proposed for recovery and isolation of valuable species from botanicals. This integration provides complete exhausting of the solid material even in the case of very low solubility of the specified solute in the extracting solvent. Selectivity of the liquid membrane ensures a preferential transport of the desired solute from the native extract into the strip solution, while the other co-extracted species remain predominantly in the native extract. 相似文献
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V. M. Boyarskii L. P. Mikhailov I. S. Sheinin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(10):623-627
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 11–13, October, 1992. 相似文献
17.
An approach to solve numerically transport equations for plasmas with spontaneously arising and arbitrarily located transport barriers, regions with a strongly reduced transfer of energy, is proposed. The transport equations are written in a form conserving heat flux and solved numerically by using piecewisely exact analytical solutions of linear differential equations. Compared to standard methods, this approach allows to reduce significantly the number of operations required to obtain a converged solution with a heat conductivity changing abruptly at a critical temperature gradient and to use large time steps in modeling the formation and dynamics of transport barriers. Computations for the tokamak JET are done. 相似文献
18.
Computer modelling of hot pressing is provided. Kinetics are described for compaction during hot pressing in a rigid die, and the change in density distribution, irreversible solid phase strain accumulation, and equivalent stresses are studied by means of the finite element method. Shrinkage during the preparation of complex-shaped articles by hot pressing pure Al2O3 powder in a graphite die without a protective atmosphere and the physicomechanical properties of the finished article are studied. Calculated and experimental results agree satisfactorily. 相似文献
19.
Mikhail Yu. Sinev Yurii P. Tulenin Olga V. Kalashnikova Viktor Yu. Bychkov Vladimir N. Korchak 《Catalysis Today》1996,32(1-4):157-162
The analysis of methane oxidation in a wide range of pressures (0.05–10 atm) demonstrates that the efficiency of CH3 radicals recombination is of great importance for high selectivity of C2 hydrocarbons formation. The relative efficiency of different “colliders” assisting the stabilization of exited C2H*6 molecules increases in the series: solid surface> Ar> He. The increase of the overall reaction rate upon increasing pressure of the inert gases in the case of catalysts having a higher surface area and more developed pore structure is likely due to the contribution of the surface-induced chain reaction in the volume of pores. 相似文献
20.
N. N. Arev S. N. Kagan E. V. Mikhailov G. V. Pugachev G. T. Cherenkov 《Measurement Techniques》1993,36(7):767-769
In this paper methods are considered for checking frequency and time standards used at control points. The most effective of the checking methods proposed is based on the use of spaceborne time-scale signals transmitted by space vehicles. The checking devices, the main computing relationships, and the test results are described.Translated from Izmeritel'naya Tekhnika, No. 7, pp. 31–32, July, 1993. 相似文献