摩托车用阀控铅酸蓄电池的研究

报道了4～9Ah系列摩托车用阀控铅酸蓄电池的研制情况,其性能及寿命均可满足摩托车的使用要求。     

基于介质顶阵的到达角估计

由于介质顶对来波的发散作用,到达平面阵的波是非平面波。本文研究基于介质顶阵的到达角(DOA)估计方法。通过对采样协方差矩阵进行远场近似(FFA)处理,用高分辨特征结构技术(MUSIc算法)进行DOA估计,得到了比较好的结果。计算机模拟结果证实了该方法的有效性。     

变厚度非平面介质罩发散系数的计算几何光学法

介质共形顶相控阵天线利用变厚度介质透镜改变相控阵波束扫描方向,理论上来说可到达半空域或更大,是一种适用于弹载、机载雷达系统的天线。本文较详细地讨论了介质罩对电磁波的发散系数的计算,给出了分析非平面变厚度分层介质对电磁波反射、折射的两种有效方法,并进行了比较。     

Transition Metal Oxide Work Functions: The Influence of Cation Oxidation State and Oxygen Vacancies

Transition metal oxides are capable of a wide range of work functions. This quality allows them to be used in many applications that involve charge transfer with adsorbed molecules, for example as heterogeneous catalysts, as charge‐injection layers in organic electronics, and as electrodes in fuel cells. Chemical and structural factors can alter transition‐metal oxide work functions, often making their work functions difficult to control. Little is known about the effects of the cation oxidation state and point defects on the oxide work function. It is necessary to understand how such chemical and structural factors affect work functions in order to controllably tune transition metal oxides for desired applications. Here, a correlation between the oxide work function and cation oxidation state is demonstrated. This correlation is attributed to the change in cation electronegativity with oxidation state. A model is presented that relates the work function to the oxygen deficiency for d⁰ oxides in the limit of dilute oxygen vacancies. It is proposed that the rapid initial decrease in work function, observed for d⁰ oxides, is caused by an increase in the density of donor‐like defect states. It is also shown that oxides tend to have decreased work functions near a metal/metal‐oxide interface as a consequence of the relationship between defects and work function. These insights provide guidelines for tuning transition metal oxide work functions.     

磁控溅射法生长CeO2/Si薄膜及其发光性质

利用反应磁控溅射法对CeO2薄膜的生长规律进行了研究.通过实验发现,溅射时氧气和氩气的比例对薄膜的成分和晶体质量有很大影响.在室温下测试了CeO2薄膜的PL谱,结果表明CeO2薄膜的发光主要来自于氧缺陷.     

重复使用运载器GN＆C技术发展趋势及特点

重复使用运载器 (RLV)将大幅度降低现役航天运载器的发射准备时间、成本 ,并提高其可靠性、安全性 ,是航天运输系统的发展方向。制导、导航与控制 (GN&C)系统是RLV的核心技术之一 ,先进的RLV的GN&C技术不仅能缩短设计周期、降低成本 ,而且对复杂多变的飞行环境具有较强的鲁棒性 ,从而提高了飞行器的安全性。指出了RLV的GN&C系统的要求、特点 ,总结了近年来该领域的研究成果 ,提出了下一步需研究的问题。     

Engineering Metal Nanoclusters for Targeted Therapeutics: From Targeting Strategies to Therapeutic Applications

Metal nanoclusters (NCs) have recently attracted great interest in biomedical applications due to their ultrasmall size, good biocompatibility, and unique molecule-like physical and chemical properties. Metal NCs can be rationally designed and integrated with various targeting moieties to achieve unique physicochemical properties and functions. For therapeutic applications, these multifunctional surface-modified NCs can provide distinctive advantages over native metal NCs, such as improved therapeutic effects and reduced side effects. In this review, the design principles of targeting strategies for metal NCs and their composites, including passive and active targeting, and physical and chemical targeting are first discussed. The authors then focus on the recent achievements in the application of metal NCs in targeted therapeutics, including chemotherapy, phototherapy, and radiotherapy. Finally, the authors’ perspectives on the challenges and opportunities of developing metal NCs in targeted therapeutics, further paving their way for potential clinical applications are provided.     

Rate adaptive resource allocation in orthogonal frequency division multiple access system using multi‐objective immune algorithm

Rate adaptive downlink resource allocation in orthogonal frequency division multiple access system is a constraint optimization problem, which is to maximize the minimum data rate of the user subject to constraint that total power cannot exceed a given value. How to handle the constraint is a key issue for constrained optimization problem. Different with the available schemes on constraint handling, the proposed algorithm converts the constraint into an objective. Then, the resource allocation is combined into a multi‐objective optimization problem. An improved multi‐objective optimization algorithm based on artificial immune system is proposed to solve it. The simulation results show that, compared with previous schemes, the proposed algorithm performs remarkable improvement in sum capacity. Copyright © 2013 John Wiley & Sons, Ltd.     

《电路理论基础》第三版修订特色

《电路理论基础》教材第三版的修订工作正在进行。本文介绍了本次修订的策略,与第二版相比的主要变化,旨在与读者和同行教师进行广泛交流,进一步完善修订工作。     

压力传感器电阻温度特性的研究

文中对压力传感器用扩散法和离子注入法制作的电阻的温度系数进行了研究。实验结果表明，同扩散法制备的电阻相比，采用离子注入法制备的电阻，其温度系数更小，且阻值能够精确控制。