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71.
JIN Jian-xun 《中国电子科技》2007,5(1):38-43
Strong current and large-scale application is the most important prospect of high Te superconductors (HTS). Practical HTS samples in various forms have been produced with high critical currents operated at economic cryogenic temperatures. Engineering applications of those HTS materials have been studied with various HTS prototype devices. The applicable HTS materials produced in different forms are verified in this paper with regard to their strong current characterizations, and the HTS applications are summarized along with the HTS prototypes made. 相似文献
72.
高温超导输电电缆的现状与发展 总被引:1,自引:0,他引:1
超导输电电缆具有截流能力大、损耗低和体积小的优点,是解决大容量、低损耗输电的一个重要途径。文章概括介绍了高温超导电缆的结构、电缆的损耗、低温冷却系统,以及中国科学院电工研究所等单位研制的75 m长高温超导电缆。文中还简要提出了高温超导电缆的应用领域和前景。 相似文献
73.
针对MgB2超导材料的中国专利申请进行了相关分析,通过对专利申请量的统计分析,研究了MgB2超导材料领域的发展趋势;通过对国内外来华专利申请量的对比分析,研究了国内外来华申请量的发展趋势以及国内主要申请人的专利申请分布,为我国专利申请人今后制定专利申请以及保护策略提供参考. 相似文献
74.
75.
从磁场矢势出发,研究了两类镜象电流对磁场的特点,得出了这两类镜象电流对在其镜平面上激发的磁场的矢势和磁感应强度与镜平面的关系,以及其量值是一电流元激发磁场相应量的两倍的结论。进而讨论了上述结论在磁场镜象法和对称电流系统(如直螺线管和螺绕管)磁场分析中的应用。 相似文献
76.
A. Sarkar S. Chattopadhyay Ravi Kumar Udayan De 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):284-289
Differently heat treated and 55 MeV Li3+ beam irradiated Bi2Sr2Ca1Cu2O8+δ (Bi-2212) high temperature superconductors have been studied from the analysis of resistivity in the normal state as well as near the superconducting transition. For all the unirradiated and irradiated samples the so-called linear temperature dependence of the normal state resistivity, in a wide temperature range, can well be understood within the variable range hopping (VRH) conduction scenario. Near and above the bulk superconducting transition, the fluctuation enhanced conductivity (paraconductivity) analysis shows a noteworthy modification of the conduction process due to radiation induced defects. 相似文献
77.
78.
79.
T. Hamada R. Morimo A. Takada Y. Yamashita K. Nakayama K. Nagata T. Yuji 《Journal of Materials Processing Technology》2000,100(1-3)
An experimental study has been carried out to investigate the synergistic effect of Ba4CuPt2O9 compounds on the critical current density of fluorine-doped YBCO superconductors. The Ba4CuPt2O9 compounds were synthesized by a solid state reaction. It was found that the synthesis temperature of the Ba4CuPt2O9 compounds was over 800°C, which was higher than that ever reported previously. In addition, the influence of Ba4CuPt2O9 compounds on the critical current density of YBCO superconductors has been investigated using two types of Ba4CuPt2O9 compounds: one is not heat-treated, i.e. source materials; and the other is heat-treated at 950°C. It was found that the former affected the orientation of the c-axes, but the latter did not have an influence on the orientation of the c-axes, but adversely affected the superconductivity of samples quenched at temperatures above 850°C. 相似文献
80.
We have derived microscopic equations for the upper critical magnetic field of aD-wave superconductor stabilized by antiferromagnetic spin fluctuations. We present numerical results for the reduced fieldh
c2(t) as a function of reduced temperaturet when the magnetic field is along thez axis and also zero-order results when it is along thex ory axis. Two differentD-wave models are considered. The angular dependence ofH
c2 forT nearT
c
is given as a function of polar angleϑ in thez−x orz−y plane. 相似文献