影响双极膜电学性能的几个关键问题的讨论

从化学动力学角度讨论了双极膜中间层催化剂的选择,双极膜中间层水的补充问题是双极膜的性能至关重要,导出阴阳膜匹配的阻抗公式,说明其电阻不是简单的阴阳膜电阻之和。     

极稀醋酸废水处理的双极性膜电渗析法

探索了用双极性膜电渗析法处理含质量分数为 0 .2 %醋酸废水的可行性 .初步实验验证废水中的醋酸可以得到有效清除 ,并且可以回收得到 3 6%以上的浓缩醋酸 .应该进一步解决的问题是设法提高过程的电流效率 ,降低过程的能耗 .     

Numerical Simulation of BJMOSFET on Current-Voltage Characteristics

A new power MOSFET Structure with a pn junction--Bipolar Junction MOSFET (BJMOSFET) has been proposed. The device has the advantages of both BJT and FET. The numerical model of the I-V characteristics of BJMOSFET has been obtained on the basis of both numerical and analytical methods. With the software package of Mathematic, we firstly calculate the gain factor, and then simulate the voltage tranmission, voltage output and voltage transfer's characteristic graphs of the BJMOSFET. The simulation result indicates that BJMOSFET has the current density, which is about 25% larger than the power MOSFET, under the same operating conditions and with the same structure parameters, except that the threshold voltage increase a little.     

离子交换树脂电再生实验研究

引　言针对目前离子交换树脂酸碱再生工艺中再生药剂利用率低、再生操作步骤繁多、大量废酸碱液的排放对环境造成污染的弊病 ,借助电渗析概念提出了一种新的离子交换树脂再生方法———电再生 ,即利用水电离出的H+和OH- 离子分别再生失效的阳、阴离子交换树脂 .本实验采用单级三隔室离子交换树脂再生装置对电再生进行了研究 .1　混床树脂的电再生实验关于混床树脂电再生 ,人们已经进行了广泛的研究[1～ 6 ] .所谓电再生实质是填充床电渗析法 ,即去离子 (EDI)净水技术 .它的进水条件苛刻 ,要求反渗透处理后出水 ,填充树脂属于再生后树脂 .…     

双极晶体管瞬态辐射光电流分流补偿法及其实验研究

采用标准分立双极元件,对双极晶体管瞬态辐射光电流分流补偿法进行了实验验证。给出了双极晶体管瞬态辐射响应及光电流分流补偿原理,比较了带补偿与不带补偿电路的瞬态响应波形。实验结果对双极晶体管集成电路瞬态辐射加固具有指导意义。     

新跨接双极三电平子模块拓扑及其控制策略

基于半桥型子模块拓扑的模块化多电平换流器不具备直流短路故障电流阻断能力,影响了低成本架空线的应用.为抑制直流故障时的短路电流,研究了 一种新跨接单极三电平子模块拓扑,解决了混合拓扑中电容不均衡充电问题.然后为应对子模块闭锁对换流站和电网可能产生的不利影响,设计了 一种新跨接正、负极三电平子模块拓扑,并分析了其过调制运行...     

A model for abrupt double heterojunction bipolar transistors

In this paper, we present a model for double heterojunction bipolar transistors (DHBTs) that takes into account Fermi–Dirac statistics as well as an arbitrary injection level. The most commonly used models in the literature for heterojunction bipolar transistors (HBTs), bipolar junction transistors (BJTs) and PN junctions can be easily obtained as a particular case of the general model presented here. In order to illustrate its features, the model is applied to an InP/GaAsSb/InP DHBT and an InP/InGaAs HBT. Copyright © 2004 John Wiley & Sons, Ltd.     

Analytical modelling of current gain and frequency characteristics under high injection levels in Si/SiGe heterojunction bipolar transistors at 77 and 300 K

This paper reports an analytical modelling of current gain and frequency characteristics in Si/SiGe heterojunction bipolar transistors (HBTs) at 77 and 300 K. Important transistor parameters, such as current gain, transconductance, cutoff frequency and maximum oscillation frequency are calculated as a function of Ge concentration in the base under different injection levels. The main physical mechanisms for the current and cutoff frequency rolloff at high injection levels are also analyzed. It shows that the high-level injection effect is more pronounced in the SiGe HBTs as a result of the increasing minority carrier concentration in the base and the Ge concentration and distribution will have a decisive influence of device performance. The results may provide a basis for the design of low temperature operation SiGe HBTs.     

铅酸电池现状及发展

分析对比了目前铅酸电池与锂电池在各个竞争领域的优缺点,并结合国内外选进铅酸电池研究进展,着重论述了未来铅酸电池的技术发展方向.     

PEM电解水制氢技术的研究现状与应用展望

基于4种电解水制氢技术性能的差异和优劣,对PEM电解槽的膜电极、多孔传输层、双极板的研究现状进行总结并展望,最后结合PEM电解水制氢技术的优势,分析该技术成本发展趋势并展望该技术的应用场景和发展方向。