超导电缆用2000W@70K制冷系统的设计和计算

叙述了用于超导电缆的2000W@70K制冷系统的设计要求、系统流程、设计概算、主要设备介绍以及调试结果等。     

Status of high temperature superconductor cable and fault current limiter projects at American Superconductor

This paper will describe the status of three key programs currently underway at American Superconductor Corp. The first program is the LIPA project which is a transmission voltage high temperature superconducting cable program, with funding support from the US Department of Energy. The 600 m cable, capable of carrying 574 MVA, was successfully installed and commissioned in LIPA grid on April 22, 2008. An overview of the project, system level design details and operational data will be provided. In addition, the status of the newly awarded LIPA II project will be described. The second program is Project Hydra, with funding support from the US Department of Homeland Security, to design, develop and demonstrate an HTS cable with fault current limiting functionality. The cable is 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The cable will be permanently installed and energized in Manhattan, New York in 2010. The initial status of Project Hydra will be presented. The final program to be discussed is a transmission voltage, high temperature superconducting fault current limiter funded by the US DOE. The project encompasses the design, construction and test of a 115 kV FCL for power transmission within a time frame of 4–5 years. Installation and testing are planned for a Southern California Edison substation. A project overview and progress under the first phase will be reported.     

硬度和电负性与掺杂二硼化镁体系超导电性、掺杂元素和掺杂比例选取的关系

通过对二硼化镁及掺杂二硼化镁超导体硬度和电负性进行研究,发现其具有较好的规律性.因此,本文提出用硬度均衡值ηcq和电负性的平均效应值χcq作为掺杂二硼化镁超导电性的一个判断标准,对今后实验工作者掺杂元素和掺杂比例的选取有很好的指导意义.     

Study on chemical-solution-deposited lanthanum zirconium oxide film based on the Taguchi method

A statistical route, Taguchi Design, applied to the analysis of experimental factors for coating lanthanum zirconium oxide films on metal substrates by inkjet printer is presented. The synthesis of lanthanum zirconium oxide precursor is derived from a chemical solution containing lanthanum acetate hydrate, zirconium propoxide, propionic acid, glacial acetic acid, and methanol anhydrous. Experimental factors analyzed by Taguchi Design show that the ratio of lanthanum acetate to propionic acid and the concentration of precursor used for inkjet printing are the dominant factors for the quality of films. With the deduced optimum conditions, lanthanum zirconium oxide films reveal good surface morphology and high out-of-plane alignment that is consistent with the Taguchi prediction.     

晶格常数与掺杂MgB2体系超导电性及硬度均衡值ηcp的关系

依据现有的MgB2掺杂实验,通过对掺杂MgB2体系超导电性与其晶格常数的研究,发现具有较好的规律性.因此本文提出用晶格常数作为掺杂MgB2超导电性的一个判断标准.为了得到晶格常数随掺杂元素及掺杂比例的变化规律,我们又研究了晶胞体积与掺杂MgB2体系硬度均衡值ηcp的关系,发现也具有较好的规律性.这些结果对掺杂二硼化镁超导电性的研究工作及今后实验工作者掺杂元素和掺杂比例的选取都有很好的指导意义.     

晶格常数与掺杂YBCO体系超导电性的关系

依据现有的YBCO掺杂实验,对掺杂YBCO体系超导电性与其晶格常数进行了研究,发现它们之间具有较好的规律性。因此提出用晶格常数作为掺杂YBCO超导电性的一个判断标准,这对探索超导机制及对今后实验工作掺杂元素和掺杂比例的选取有很好的指导意义。     

近零介电常数区超导薄层的Goos-H?nchen位移

Goos-H?nchen(GH)位移是一种特殊的光学现象,具有广泛的应用.构造材料光学性质的差异对同一结构的GH位移有很大影响.在近零介电常数区,本文比较研究了不同偏振态的光波入射到超导薄层上的GH位移.当以大于临界角的入射角入射时,s偏振光的GH位移始终保持为正值,而p偏振光的GH位移的正负与超导材料的介电常数为零时的波长相关联.当入射光波长大于该波长时,GH位移会出现负值.相关参数对不同偏振态下的GH位移的影响存在较大差异.相对于p偏振光,GH位移在s偏振光入射时随相关参数的变化规律较为简单.超导材料在光子学领域具有广泛的应用,计算结果为基于超导材料的新型光子学器件研究开发提供了参考.     

Magnetic response of ferromagnet-superconductor bilayers

Magnetic measurements on a ferromagnet/insulator/superconductor (La_2/3Ca_1/3MnO₃/SrTiO₃/YBa₂Cu₃O_7−x) structures were performed with the field applied parallel to the plane of the film. We observed an evidence of a modification of the ferromagnetic domain structure in the magnetic layer induced by the superconducting transition in the neighboring superconducting YBa₂Cu₃O_7−x layer.     

Studies on Characteristic of Infrared Spectra of Superconductor Bi-Sr-Ca-Cu-O System

Abstract

We made the superconductor of Bi₂Sr₂CaCu₂O_γ by the solid state reaction. According to the results of measurement by infrared spectrophotometer with the varying of wave number from 4000 to 400 cm^?1. We discovered three infrared absorption peaks at room temperature, i.e., peak A₁ at 500–550 cm^?1, peak A₂ at 800–840 cm^?1 and peak A₃ at 1370–1420 cm^?1. We find that peak A₁ is due to impure phase, peak A₂ is related with the crystal structure and peak A₃ is caused by the vibration of the atom layers of calcium.     

活性炭富集电感耦合等离子体原子发射光谱测定铋系超导粉中痕量铁

建立了电感耦合等离子体原子发射光谱(ICP-AES)测定超导粉中痕量铁的新方法。优化了仪器工作参数,对痕量铁测定时的基体干扰及消除干扰的方法进行了系统研究,结果表明:大量存在的基体元素产生一定基体效应,并使重现性变差,且由于铁含量甚微,仪器灵敏度不能满足测定的要求,需采用分离富集方法以提高测定结果的准确度和精密度。以三乙醇胺掩蔽基体元素铋和铜,在适宜的酸度条件下,铁与邻二氮菲生成配合物,以活性炭定量吸附,用1∶1硝酸解吸,并对分离富集条件进行了优化。对模拟标准样品进行测定,分析结果与理论值一致,相对标准偏差为2.4%,方法检出限为0.033μg.g-1。该方法已用于超导前驱粉样品中痕量铁的分析,结果令人满意,并进行了回收实验,回收率为95.6%～98.0%。