超导线材短样测试装置测量系统

介绍了自行研制的超导线材短样测试装置的实时测量系统,包括温度、压力、液位、电流、电压降测量5个方面.该系统基于计算机和MCGS组态软件,选用合适的传感器和测量方法,采用A/D数据采集卡实现超导线材短样测试装置数据的实时显示和记录.测量系统具有操作简便、运行可靠等优点,已经通过与超导线材短样测试和超导磁体失超等实验,给出实验结果.这些结果表明,测量系统能满足超导线材短样测试装置的各项数据测量要求.该系统实现了低温测量和电量测量的有机结合,其成功研制为应用超导低温制冷系统的数据采集提供了参考.     

基于超导磁储能装置的风电并网功率控制研究

风电系统输出功率的波动性和间歇性作为制约风电系统大规模并网的关键因素,给电网带来的不利影响越来越受到重视。为了提高风电系统并网功率的稳定性,本文对基于超导磁储能装置的风电并网功率控制做了研究。首先在理论上抽象描绘出风电并网系统的结构图,其次阐述超导磁储能装置抑制风电并网系统功率波动和震荡的原理,最后利用仿真软件matlab/simulink对风电并网系统进行了仿真分析,验证了采用超导磁储能装置稳定风电并网功率的正确性。     

利用脉冲强磁场测量超导材料的HC2和JC（H）

提出了利用脉冲磁场对超导材料ＨＣ２和ＪＣ（Ｈ）的测量方案，并研制出了测试装置，对ＮｂＴｉ，Ｎｂ３Ｓｎ，Ｎｂ３Ｇｅ及掺ＴｉＮｂ３Ｓｎ等超导材料的ＨＣ２和（ＨＣ（Ｈ）进行了测量，得到了理想的测试结论和有益的测试经验。     

超导变压器的研制和试验研究

叙述了一台小型超导变压器的设计、研制和试验研究。这台超导变压器的实测量大容量达２．４ｋＶＡ。研究结果表明，交流超导线对超导变压器甚为重要，国产线材虽可用于超导变压器工频交流电的工作条件，而其交流损耗尚需降低；超导变压器在技术上是可行的，具有许多优点，但设计中应特别注意降低低漏磁损耗。     

超导电力装置失超检测的基础研究

超导电力装置的失超会影响超导电力设备的运行和安全，是超导电力设备技术实用化有待深入研究的一个重要问题。对国内外通用的超导装置失超检测方法进行了分析，并根据电力系统中超导装置失超检测的特点，对高温超导线材在不同幅值的动态电流作用下的失超特性进行了试验研究，通过对试验数据的分析，对高温超导线材的失超特性有了较精细的理解，并在此基础上提出了超导电力装置失超先兆检测及其失超保护设计的新概念。     

超导在空间技术中的应用 二

上期介绍了高温超导材料的空间热处理和超导的空间应用。在超导的空间应用中只介绍了超导陀螺、空间超导磁体系统、超导助推发射装置和空间超导贮能。现在继续介绍超导的空间应用。内容涉及超导天线,空间用超导电子器件。     

超导在空间技术中的应用（一）

简介了超导技术在空间技术中的应用情况。其中还包括高温超导材料的空间热处理的国内研究结果的概述。在超导的具体空间应用中介绍了超导陀螺、空间超导磁体系统、超导助推发射装置、空间超导贮能、超导天线、空间用的超导电子器件的应用情况.     

2K以上超导转变温度标准的测量装置

本文描述了利用互感法测量超导转变温度的原理、测量装置和测量方法。测量装置包括:低温恒温器、两种超导材料(铅和铟)的超导器件、简单的互感电桥线路及测量系统。测量结果的重复性小于±1mK,综合不确定度为±3mK(置信度为99%)。从而建立了2K以上超导转变温度测量装置。     

超导磁悬浮列车的超低温系统

磁悬浮列车是正在进行试运行的高速交通工具之一.介绍了日本目前关于超导磁悬浮列车中的超低温系统的研究现状、工作原理、超低温系统、在超低温系统这一部份中,介绍了超导磁体、氦制冷装置、车用制冷机、低温装置的研制情况.     

氦制冷机的效率

随着超导技术发展和广泛应用,它对低温系统的容量要求也越来越庞大。对于大型超导磁体系统的氦制冷系统,其效率直接影响大型超导装置的运行费用。论述了影响氦制冷机效率的各种因素,并指出了提高制冷机效率的各种基本途径。     

Fabrication of Al thin wire by utilizing controlled accumulation of atoms due to electromigration

A technique of fabricating metallic thin wires by utilizing effective collection of the atoms caused by electromigration, which is a phenomenon of atomic diffusion due to high current density, is presented. Atoms diffused by electron flow can be used for making metallic thin wires. To form metallic thin wire at the intended position, we used passivated Al thin film line that had a slit at the anode end of the line as a test sample. As a result of current applying, the Al thin wire of a high aspect ratio was fabricated.     

Current and current density distribution in parallel superconducting wires in a planar array in the meissner state

The current distribution in parallel superconducting wires is influenced by the Meissner effect. In order to treat this quantitatively, the behaviour of superconducting cylinders in an inhomogeneous magnetic field was examined and the results were applied to a planar arrangement of parallel superconducting wires. How the current distribution between the conductors and the current density distribution along the circumference of each wire behave, if the distance between the conductors is varied, is also discussed, together with the effect of varying the number of wires on the current distribution. Finally the current distribution in a planar array of superconducting wires is compared with the current density distribution in a thin superconducting layer. Experimental results supporting the above mentioned theoretical considerations will be presented.     

电气火灾中铜导线火烧痕的研究

采用金相分析和宏观分析方法对铜导线火烧痕的模拟试验和火灾现场残留物进行了观察和研究.结果发现,现行国家标准GB 16840.4-1997《电气火灾痕迹技术鉴定方法第四部分:金相法》中对铜导线火烧痕的特征描述有不完善之处.铜导线未熔化前与国标所述相似,即显微组织均为粗大等轴晶,无空洞;但熔融后的铜导线的显微组织主要是等轴晶、树枝晶和Cu2O-Cu共晶组织,且有时会出现少量孔洞.     

Infrared photodetectors in heterostructure nanowires

We report on spectrally resolved photocurrent measurements on single self-assembled nanowire heterostructures. The wires, typically 3 microm long with an average diameter of 85 nm, consist of InAs with a 1 microm central part of InAsP. Two different sets of wires were prepared with phosphorus contents of 15+/-3% and 35+/-3%, respectively, as determined by energy-dispersive spectroscopy measurements made in transmission electron microscopy. Ohmic contacts are fabricated to the InAs ends of the wire using e-beam lithography. The conduction band offset between the InAs and InAsP regions virtually removes the dark current through the wires at low temperature. In the optical experiments, interband excitation in the phosphorus-rich part of the wires results in a photocurrent with threshold energies of about 0.65 and 0.82 eV, respectively, in qualitative agreement with the expected band gap of the two compositions. Furthermore, a strong polarization dependence is observed with an order of magnitude larger photocurrent for light polarized parallel to the wire than for light polarized perpendicular to the wire. We believe that these wires form promising candidates as nanoscale infrared polarization-sensitive photodetectors.     

高速硫酸盐镀锌工艺及镀层性能

在高碳钢丝的高速硫酸盐镀锌电镀槽液中,采用硫锌-75作添加剂,以提高电流密度上限、电流效率和镀层质量.SEM、X射线衍射的试验结果表明:镀层结晶细腻,晶面取向优化,镀层柔软,富有延展性.生产实践表明:镀锌钢丝在拉拔过程中的锌层损耗、模具损耗和生产成本降低,产品质量得到了提高.     

Magneto-Impedance Effect of Composite Wires Prepared by Chemical Plating under DC Current

Nano-Micro Letters - CuBe composite wires of 100 μm in diameter coated with a layer of NiCoP were prepared by a chemical plating method under DC current (CPUDC). The influences of DC current...     

Experiment and Numerical Modeling of Current Distributions Inside REBCO Tapes of No-Insulation Superconducting Magnet Coils Under Time-Varying Fields

Journal of Superconductivity and Novel Magnetism - The current densities flowing in high-temperature superconducting wires are mostly non-uniform during operations (caused by the screening current...     

Enhancement of bending strain tolerance and current carrying property of MgB2 based multifilamentary wires

The effect of bending strain on current carrying capacity of MgB₂ multifilamentary wires was studied with 4, 8 and 16 multifilamentary wires. The critical current density (J_C) of straight wires and bent wires with 5, 10, and 15 cm diameter was measured. Both annealed & bent and bent & annealed wires were used for measurement. The J_C of annealed & bent wires were found to decrease with decrease in bent diameter and the rate of degradation of J_C decreased with increasing number of filaments, while bent & annealed wires almost retained its J_C at all diameters studied.     

Effect of pulsed DC current on neck growth between tungsten wires and tungsten plates during the initial stage of sintering by the spark plasma sintering method

The spark plasma sintering of tungsten wires to tungsten plates was investigated to assess the effect of the current. Neck growth between wires and plates was about 1.5 larger in the presence of current than when the current was absent. The neck growth was controlled by an evaporation–condensation mechanism. The mechanism, however, does not relate to the sintering of tungsten, but to the control of a surface oxide reduction, in agreement with previous investigations.     

电线电缆带电燃烧研究进展

分析了当前国内外在电线电缆带电燃烧方面的研究进展,主要关注了在役电缆温升特性、带电电缆故障着火机理和电流变量与燃烧特性的相互影响,分别对应了带电电线电缆起火本质原因、引燃特性及火焰蔓延特性。在电缆温升特性方面,分析了以热路模型或者数值计算模型为基础所建立的各类电缆线芯温度预测模型,并介绍了基于电缆温度预测模型所建立的各类线缆温度监测系统。在带电电缆故障着火机理方面,分析了由于绝缘层表面导电路径、高温导致空气电离及绝缘材料热解而形成的电弧故障引发火灾,以及由于短路、过载和接触不良等导致电缆线芯过热引发火灾的机理,并揭示了不同故障之间的相互诱发关系,分析了多种故障综合作用引发火灾的机理。在带电电缆燃烧特性方面,分析了电场与燃烧的相互影响关系与机理,并揭示了外部引燃条件下,通电电流变量对电缆燃烧特性及蔓延速度的影响规律,分析表明在制定电缆安全的相关标准和规范时,需考虑电缆火灾中持续通电电流的影响。