铅酸蓄电池负极添加剂的研究

用电化学方法对负极添加剂进行了筛选,发现生物碱对铅电极有积极影响;电池试验表明,生物碱可提高负极活性物质利用率。     

Negative refraction of a surface plasmon polariton

We study theoretically the negative refraction of a surface plasmon polariton. The system we consider consists of a vacuum that is in a contact with two metals that each fill a quarter space with a periodic boundary between them. The interface of each of the metals with the vacuum supports a surface plasmon polariton. When a surface plasmon polariton passes through the periodic boundary between the metals it transforms partly into the Bragg beams of the refracted and reflected surface plasmon polaritons and partly into volume waves in the vacuum. A suitable choice of the period can ensure that the only propagating Bragg beams of the refracted surface plasmon polariton are the specular beam and the (?1)-order beam, which is negatively refracted. With a suitable choice for the form of the profile function and its amplitude the specular beam can be made to vanish.     

一种基于Gm-C的高Q值模拟中频带通滤波器设计与实现

设计并实现了一种基于Gm-C二次节(Biquad)结构的6阶切比雪夫Ⅰ型模拟中频带通滤波器,中心频率为46MHz,带宽为2.046MHz.其中Biquad结构中加入了负阻抗单元,增加输出阻抗,实现滤波器的高Q值(品质因数).跨导放大器(Operational transconductance amplifier,OTA)单元使用源极负反馈技术,优化了OTA的线性性能.整个滤波器电路采用0.35μm CMOS工艺实现.经过仿真验证,滤波器的通带纹波是2.704dB,1.5倍带宽处衰减大于21dB.在3.3V电源电压情况下,滤波器的总电流消耗为8.87mA.     

多峰I—V特性的共振隧穿量子器件

讨论了电子对双势垒共振隧穿的现象和特性,较为详细地论述了近年来发展起来的具有多峰I—V特性的共振隧穿量子器件的原理、结构和电路应用,最后展望了这类器件的发展前景。     

一种新型硅三端负阻器件

提出并研制成一种新型硅三端负阻器件。该器件由一n沟耗尽型MOS管、一横向pnp双极晶体管和一个电阻集成而得。它具有“双负阻”特性和正阻区阻值易于控制等特点。由理论计算出的器件I_c—V_(CB)特性和负阻参数与实验结果符合良好。     

关于缩短大电流开关二极管反向恢复时间的研究

通过长期的工作实践，阐述了适当条件下的金扩散对缩短反向恢复时间，提高二极管2CK28开关速度，满足了反向恢复时间，改善了二极管的反向特性。     

变频器在链条炉系统中的应用

本文介绍了链条炉的定义，链条炉应用变频调速的意义，链条炉控制系统的原理，锅炉采用变频调速控制的优点，变频调速的控制方法和逻辑，链条炉采用变频调速装置的节能分析。     

人工免疫系统及其算法

该文阐述了人工免疫系统(AIS)的基本概念,讨论了几种典型的算法,包括基于免疫系统基本机制的免疫算法,基于免疫特异性的否定选择算法,基于免疫系统克隆选择理论的克隆选择算法,基于接种疫苗及免疫多样性的免疫进化算法,AIS与神经网络混合智能系统和模糊免疫系统以及威胁模型等。简述了AIS发展历史,按年代顺序介绍了AIS 在若干具有代表性的领域中的应用情况。最后通过对AIS 的特性和存在问题的分析,展望了今后的研究重点和发展趋势。     

一种微波有源滤波器的实验研究

研究了一种利用耦合负阻法制作微波有源带通滤波器的方法。基于这种方法，制作了一个Ｃ波段的单级微带端耦合滤波器。实验结果表明，利用耦合负阻到谐振腔的方法，可明显改善滤波器的通带特性。     

Effect of sweeping voltage and compliance current on bipolar resistive switching and white-light controlled Schottky behavior in epitaxial BaTiO3 (111) thin films

Bipolar resistive switching (RS) phenomenon without required electroforming has been observed in epitaxial (111)-oriented BaTiO₃ (BTO) thin films deposited by PLD technique on conducting Nb-doped substrate of SrTiO₃ (NSTO). Negative differential resistance (NDR) is observed at about −5 V when the maximum of positive voltage exceeds 7 V and the compliance current is more than 1.5 mA. And bipolar resistive switching has also been observed. In addition, the resistance of LRS decreases with increasing compliance current or the maximum of positive voltage while that of HRS barely changes, and the resistance of HRS increases with increasing the absolute of maximum of negative voltage while that of LRS scarcely changes. A typical rectifying behavior is observed when the maximum of positive voltage is less than 4 V (such as 2 V). In this case, the reverse biased current is strongly enhanced under illumination of white-light, and vice versa. The resistance of LRS and HRS can be controlled by the applied voltage or the compliance current. The rectifying behavior can be controlled by the white-light. The transition from rectifying behavior to bipolar resistive switching can be controlled by the applied voltage. The above results were discussed by considering the oxygen vacancies that can trap or release electrons as a trapping layer at the Pt/BTO interface.