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991.
We have discussed the restoration mechanism of the spontaneous symmetry breaking, C 2 spatial symmetry breaking mechanism, and spin glass-like mechanism in high- T c cuprates from the standpoint of field-theoretical formula. It is suggested strongly that quantized massive gauge fields, which contain effects of spin fluctuations, charge fluctuations, and phonons, might be mediating Cooper pairing in high- T c cuprates. 相似文献
992.
I. A. Auwal B. Ünal A. Baykal U. Kurtan M. D. Amir A. Yıldız M. Sertkol 《Journal of Superconductivity and Novel Magnetism》2017,30(7):1813-1826
In this study, Y3+ ion-substituted M-type barium hexaferrites (BaM; BaFe12O19) were fabricated via facile ceramic route. As-prepared powders were characterized by X-ray powder diffractometry (XRD), Fourier transform infrared (FT-IR) spectroscopy, and impedance spectroscopy. XRD (Rietveld) analyses confirmed the presence of a single characterization of all samples (except x = 0.0 and 0.1 samples). The crystallite sizes of products are found in the range of 47.2–63.2 nm. Spectral analysis (FT-IR) also presented the formation of spinel structure for all products. The ac conductivity of the substituted samples was found to initially decrease slightly with increase in Y3+ compared with unsubstituted, and then variation tendency changes at the medium substitution ranges are observed with a different attitude against temperature. In the end, the lower conductivity for high substitutions is recorded and increases as functions of frequency while it also increases with the elevation of temperature. It was observed that ac conductivities of products increased by increasing frequency which indicate that observed ac conductivity is due to both electronic and polaron hopping mechanism. 相似文献
993.
Microfluidics: Inertial Microfluidic Cell Stretcher (iMCS): Fully Automated,High‐Throughput,and Near Real‐Time Cell Mechanotyping (Small 28/2017) 下载免费PDF全文
994.
995.
This paper describes the reduction of titanium dioxide with a mixture of silicon carbide and silicon powders at a temperature of 1550°C under vacuum. It has been shown that the use of the combined reductant enables the preparation of the ternary phase Ti3SiC2 through concurrent carboand silicothermic processes. The optimal compositions for Ti3SiC2 formation are TiO2 + (1.5–x)SiC + 2xSi with x = 0.4–0.5. The Ti3SiC2 yield then reaches 96 wt %. 相似文献
996.
I. E. Strelnikova E. E. Grinberg Yu. I. Levin A. E. Amelina V. I. Rakhlin 《Inorganic Materials》2016,52(12):1250-1253
We have studied reactions of metallic magnesium with ethyl cellosolve and a mixture of ethyl cellosolve and tetraethyl orthosilicate and demonstrated the possibility of preparing a mixed magnesium–silicon cellosolvate that can be used as a precursor for the synthesis of forsterite and enstatite. 相似文献
997.
V. I. Gorbatov V. F. Polev I. G. Korshunov V. P. Pilyugin A. L. Smirnov S. G. Taluts 《High Temperature》2016,54(2):294-296
Measurement data are given for the thermal diffusivity of Zr–2.5% Nb and Zr–50% Nb alloys both with the usual polycrystalline structure and with submicro- and nanocrystalline structures at high temperatures, which were determined in the automated mode using the dynamic technique of plane temperature waves. 相似文献
998.
The phase equilibria of immiscible binary systems (water–n-hexane, water–n-pentane) are investigated using a constant-volume piezometer. The measurements were performed under normal conditions, based on P,V,T,x-data obtained in the temperature range of 300–680 K, pressures up to 60 MPa, and in a wide range of densities. Based on the experimental data, we constructed phase diagrams in the P–T and T–x coordinates and determined the Krichevskii parameters for the system of water–n-hexane near the critical point of the pure solvent. 相似文献
999.
A. G. Alibekov A. Yu. Mollaev L. A. Saipullaeva S. F. Marenkin I. V. Fedorchenko 《Inorganic Materials》2016,52(4):357-360
The transport properties of granular Cd3As2 + MnAs (44.7% MnAs) composite structures have been studied near room temperature at high hydrostatic pressures of up to 9 GPa. The results demonstrate that the composite undergoes a structural phase transition and has a pressure-induced negative magnetoresistance. 相似文献
1000.
A new method has been proposed for the synthesis of catalytically active 80 wt % SnO2 + 20 wt % CeO2 materials supported on glass fiber, which involves the use of an ethanolic film-forming solution based on cerium(III) nitrate and salicylic acid, with the addition of tin(IV) chloride. We have studied the morphology of the materials thus prepared and assessed their catalytic activity for the deep oxidation of methane. The results indicate that the appreciable catalytic activity of the materials is ensured by their uniform distribution over the support surface and the small oxide aggregate size ( 10 μm), which is due to the use of the filmforming solution of the proposed composition. 相似文献