高功率反向开关晶体管开关寿命特性

研制了10 kV高压反向开关晶体管（RSD）开关组件。在重复频率0.2 Hz、峰值电流约107 kA、峰值功率约1 GW、单次传输电荷约20 C、单次传输能量约100 kJ条件下,实验次数达50 000多次;主要研究了RSD开关的静态伏安特性随实验次数的变化趋势。采用数值分析的方法,统计拟合得到了长脉冲大电流条件下RSD开关的寿命模型,并依据失效判据初步预估RSD开关的寿命可达107次。     

反向电流一定会相斥吗?——对楞次定律应用中一个问题的澄清

在一次楞次定律习题课中，有这样一个题目：如图1所示，光滑的水平桌面上放着两个完全相同的金属环a和b，当一条形磁铁的N极竖直向下迅速靠近两环时，则     

EAST反向束在不同电流平台下注入的实验分析

对EAST装置在相同束放电参数不同等离子体电流平台下开展的束反向注入实验进行了比较分析，并利用NUBEAM程序分析了不同的等离子体电流放电平台对束电流驱动、束功率沉积、束功率沉积分布及束能量损失的影响，以此来寻求优化的注入本底等离子体参数。结果表明，较高的电流平台更有利于束与等离子体的作用以及更有效提高本底等离子体温度、束驱动电流及等离子体旋转，更有效改善等离子体约束品质。     

SiC Schottky结反向特性的研究

对Ti/6H-SiC Schottky结的反向特性进行了测试和理论分析，提出了一种综合的包括SiC Schottky结主要反向漏电流产生机理的反向隧穿电流模型，该模型考虑了Schottky势垒不均匀性、Ti/SiC界面层电压降和镜像力对SiC Schottky结反向特性的影响，模拟结果和测量值的相符说明了以上所考虑因素是引起SiC Schottky结反向漏电流高于常规计算值的主要原因.分析结果表明在一般工作条件下SiC Schottky结的反向特性主要是由场发射和热电子场发射电流决定的.     

回旋管磁场电流调节器的改进

一、引言 最近,用电子回旋共振加热(ECRH)产生热电子等离子体引起了人们很大兴趣。为开展ECRH在聚变装置的应用研究,我们在一个简单磁镜MM-2中,用频率15千兆赫回旋管建立热电子等离子体,并开展了一系列热电子环物理实验研究。在该装置实验中,我们发现,回旋管正常工作的关键是它的主磁场电源的稳定度。它要求电源输出500A时,电流稳定度优于0.05％。最早该电源用28只三极管并联作为电流调节器,由于管子参数分散性大,均流和     

A Backward-Looking Optimal Current Lattice Model

An optimai current lattice model with backward-looking effect is proposed to describe the motion of traffic flow on a single lane highway. The behavior of the new model is investigated anaiytically and numerically. The stability, neutrai stability, and instability conditions of the uniform flow are obtained by the use of linear stability theory. The stability of the uniform flow is strengthened effectively by the introduction of the backward-looking effect. The numerical simulations are carried out to verify the validity of the new model. The outcomes of the simulation are corresponding to the linearly analyticai results. The analytical and numerical results show that the performance of the new model is better than that of the previous models.     

进气量对强流正离子源反向电子流的影响研究

分析了EAST-NBI离子源束引出过程中反向电子的产生及物理特性,对典型情况下的进气量对离子源的影响进行了计算和实验研究。实验结果发现,质子比受进气量影响较小,进气量与反向电子流呈明显正相关。     

基于电磁诱导透明的原子自旋波读出效率实验研究

光信息的存储与读出效率对量子信息领域有着重要的意义, 电磁诱导透明是最常用的方法. 本论文基于电磁诱导透明方法首次在热原子系综中实验研究了反 向和同向读取原子自旋波信息的回复效率, 并对实验结果进行了理论分析, 实验和理论的结果都表明同向和反向读出效率的高低取决于原子系综中原子自旋波的强度空间分布. 这一实验研究将会对热原子系综中的光与原子信号相互转换过程的应用有着一定的意义. 关键词： 电磁诱导透明 反向传播 原子系综     

夫兰克-赫兹实验栅极电流的研究

测量了夫兰克赫兹实验中氩气管的经典线性伏安特性曲线,分别从栅极电流和板极电流的实验数据中反应出的氩原子第一激发能级量子化吸收的特性,并对量子吸收理论在实验中的体现加以探讨。     

用计算机测量PN结的反向物理特性

本对PN结反向物理特性，应用电子技术和计算机技术实现了对实验过程的控制和效据处理。     

聚变装置中真空室上涡流的分析

本文研究了聚变装置真空室上的涡流问题,将真空室上的涡流看作面电流密度并定义一矢势的法向分量来描述它。详细地叙述了求解真空室上感应涡流的计算方法,对HTU托卡马克实验装置真空室上涡流的大小、分布形式及衰减情况进行了分析。     

HT-7U装置极向场电源变流系统的研制

介绍了HT-7U极向场电源中所使用的变流系统，提出了一种新的四象限运行控制方法，解决了极向场电源设计和制造的难点。实现了15kA的有环流运行。     

Persistent current in a superconductor/quantum-dot ring/superconductor system

By means of the non-equilibrium Green's function technique, the inter-dot and Josephson currents in a superconductor/quantum-dot ring/superconductor (S/QDR/S) system are theoretically investigated. We found that a persistent current can coexist with the Josephson current in this hybrid QDR system when the inter-dot currents are all flowing in the clockwise (or anticlockwise) direction. The magnitude and direction of the persistent current can be controlled experimentally by the adjustment of some structure parameters, such as the quantum dot (QD) levels, the phase difference of the two external superconducting leads and the magnetic flux phase factor.     

磁场渗透导体壳的实验研究

本文叙述了测量阶跃脉冲垂直磁场和水平磁场渗透HL-1装置各种比例导体壳时间常数的方法。对空芯和铁芯变压器情况分别做了实验。给出了相应结果。     

光导开关中的感生电流与传导电流

利用数值方法对线性条件下横向光电导开关的感生电流和传导电流进行了计算和比较.结果表明在特定的实验条件下，感生电流才会对输出电脉冲产生较大的影响.分析了超快光电导开关在不同实验条件下传导电流与位移电流对输出电脉冲的影响.根据该结论，给出非线性模式下，光电导开关电脉冲超快上升沿小于载流子以饱和速度在电极间渡越所需时间的现象. 关键词： 光电导开关 传导电流 位移电流     

涡电流加热实验仪的研制

简述了涡电流加热的实验原理,并设计了涡电流加热实验仪.该实验仪利用给带铁芯的线圈通电产生的磁场,通过磁场变化产生涡电流,同时释放出热量达到涡电流加热的目的.比较了几种金属的涡电流加热与同种金属在不同电源频率下的涡电流加热的效果.     

Nondissipative Orbital Currents in Finite Quantum Systems: A Comparative Study

The idea of nondissipative, persistent currents in mesoscopic metallic or semiconducting rings and cyclinders appears counterintuitive, because it contradicts our experience with currents in macroscopic metals. On the other hand such orbital currents are well known properties of atoms. A comparative study of nondissipative ring currents in different finite quantum systems is therefore of interest. In this paper the properties of atoms, mesoscopic metallic or semiconducting rings and cylinders and elongated molecules called carbon nanotubes are discussed and compared.     

光纤（光学）电流传感器的现状及发展

本文系统地评述光纤（光学）电流传感器研究的现状和存在的主要问题，给出不同调制方式的几种传感头的基本结构，分析比较它们的优缺点。针对影响传感器精度的因素，讨论目前采取的一些解决方法。文中指出光纤（光学）电流传感器的发展方向。     

Numerical simulation of electron cyclotron current drive characteristics on EAST

Electron cyclotron current drive （ECCD） will be applied in the EAST tokamak during its the new campaign. In order to provide theoretical predictions for relevant physical experiments, some numerical simulations of ECCD with the parameters of EAST have been can＇ied out by using TORAY-GA code based on the understanding of ECCD mechanisms. ECCD efficiencies achieved in different plasma and electron cyclotron （EC） wave parameters are given. The dependences of ECCD characteristics on EC wave injection angle, toroidal magnetic field, plasma density, and temperature are presented and discussed.     

The leakage current mechanisms in the Schottky diode with a thin Al layer insertion between Al0.245Ga0.755N/GaN heterostructure and Ni/Au Schottky contact

This paper investigates the behaviour of the reverse-bias leakage current of the Schottky diode with a thin Al inserting layer inserted between Al0.245Ga0.755 N/GaN heterostructure and Ni/Au Schottky contact in the temperature range of 25-350°C. It compares with the Schottky diode without Aluminium inserting layer. The experimental results show that in the Schottky diode with Al layer the minimum point of I-V curve drifts to the minus voltage, and with the increase of temperature increasing, the minimum point of I-V curve returns the 0 point. The temperature dependence of gate-leakage currents in the novelty diode and the traditional diode are studied. The results show that the Al inserting layer introduces interface states between metal and Al0.245Ga0.755N. Aluminium reacted with oxygen formed Al2O3 insulator layer which suppresses the trap tunnelling current and the trend of thermionic field emission current. The reliability of the diode at the high temperature is improved by inserting a thin Al layer.