微型温差电池的研究进展

诸如MEMS,微电子系统,甚至于系统芯片等微型化固态装置的应用日益广泛,这类装置通常需要具有低输出功率、高输出电压的微型电源为其供电。基于薄膜热电材料制造的微型温差电池即是一种典型的可以满足上述要求的微型电源。综观已报道的微型温差电池结构,按热传导的方向可分为两类:横向结构和纵向结构。对于横向结构,热量沿着热电腿表面传导,而纵向结构的热量则是沿热电腿的厚度方向传导。综述了此两种结构微型温差电池的最新进展。     

锌镍电池新进展

综述了锌镍电池近期的发展 ,主要研究包括锌电极、镍电极、电解液、隔膜及相关技术。锌电极 :添加Ca (OH) 2 和金属氧化物 (PbO、Bi2 O3 、CdO、Ga2 O3 和Tl2 O3 ) ;渗入Pb2 + 或Ta、Cd。镍电极 :含有Ni(OH) 2 、Ca(OH) 2 和Zn(OH2 ) ;由球状氢氧化镍与粉状氢氧化镍混合而成 ;Ni(OH) 2 颗粒含有Zn ,并用Cd覆盖在镀镍纤维基底上填充活性物质。电解液 :添加硼酸盐、磷酸盐 ;加入Li+ 和SiO2 -2 。隔膜 :无纺尼龙布 ,无纺聚乙烯纤维膜 ,无纺尼龙布和微孔聚丙烯。相关技术 :增添催化复合装置 ;采用碱性固态电解质。近年来 ,锌镍电池的性能有了明显的提高 ,并进入了生产和实用阶段。这种电池可望用于手提式仪器及电动汽车动力电源     

Recent progress in high-power blue-violet lasers

The property of GaInN-AlGaN heterostructures and GaInN multiple quantum well (MQW) gain GaInN laser diodes with low internal loss are described. GaInN blue-violet laser diodes have been developed as a light source for optical disk recording. However, the threshold current density of these diodes has been difficult to reduce and remains high at around 3-4 kA/cm/sup 2/. This is thought to be due to the large transparency current density Jt and the large optical internal loss /spl alpha//sub i/. Recently, the internal loss was successfully reduced to 13.6 cm/sup -1/ by optimizing the design of the near active region and achieved stable continuous operation under 50-mW continuous wave at 70/spl deg/C. Other laser characteristics such as far-field patterns and laser noise have also been improved for optical disk use.     

The forward and inverse problems of electrocardiography

This article summarizes the theoretical underpinnings of both the forward and inverse problems of electrocardiography. Space limitations prohibit describing all of the research work done in these areas, and the author apologizes in advance for any omissions on this account or due to oversight. The article should enable one to gain a better qualitative and quantitative understanding of the heart's electrical activity     

军用通信电池技术进展

阐述了军用电池的地位与作用;综述了我国今后要发展的几种军用通信电池,特别是高性能一次锂电池、金属氢化物-镍蓄电池和锂离子蓄电池近几年来在技术上取得的进展与重大突破,并指出了这些发展中的新型电池今后改进与提高工作的重点。     

Recent progress in group-III nitride light-emitting diodes

We review the recent progress of nitride-based light-emitting diodes (LEDs) and discuss the dislocation issue and luminous efficiency. First, candela-class blue LEDs have been developed. InGaN layer was used for nitride LEDs instead of GaN active layer. The quantum-well-structure InGaN active layer dramatically improved the external quantum efficiency. There are a number of threading dislocations in epitaxial layer of nitride-based LEDs. InGaN-LEDs, however, have quite high external quantum efficiency. With regard to this, it is thought that the fluctuation of indium mole fraction is strongly related to the high external quantum efficiency. We also discuss the method to improve the external quantum efficiency of nitride-based LEDs     

Symbolic approach to inverse problems in method of moments

Symbolic computational systems introduce some unique features in computational engineering. There have been several papers published on the solution of differential equations under given boundary conditions by symbolic systems. The finite element formalism has received prime attention in the course of development of symbolic computation in engineering. The main idea has been to develop a symbolic FEM package to reduce the burden of manual algebra, eliminate errors introduced by numerical quadrature, and improve the efficiency of element generation. This work discusses a symbolic solution to electromagnetic linear antenna problems. The solution is a method of moments that transforms Pocklington's integral equation to a matrix equation. The symbolic system is used to produce (1) analytical integration, (2) the parametric expression for the input impedance and (3) computational code for forward and reverse problem of the input impedance.     

防覆冰涂料的研究进展

介绍了覆冰对电网的影响,综述了防覆冰涂料技术的研究现状,分析了各种防覆冰涂料的防冰原理及优缺点;并指出了超疏水仿荷叶涂料及其结合光热型涂料是防覆冰涂料技术的研究方向,具有良好的应用前景。     

Recent progress of FET-type ferroelectric memories

Abstract

Recent progress of FET-type ferroelectric memories is reviewed. It is described that insersion of a buffer layer between the ferroelectric film and Si substrate is essential in preventing interdiffusion of the constituent elements. It is also shown, however, that existence of the buffer layer degrades the data retention characteristic severely. Necessary conditions to solve the short retention time problem are discussed, paying particular attention to comparison of MFIS (metal-ferroelectric-insulator-semiconductor) and MFMIS structures. Finally, a novel ferroelectric-gate FET is proposed, in which the depolarization field is expected not to be generated in the ferroelectric film.     

氟离子电池的研究进展与挑战

锂离子电池的能量密度提升空间有限,且受资源限制,因此开发其他电池体系成为研究热点。F^-的电负性高、半径小、质量轻,作为电子载体能够提供高能量密度,因此,基于F^-穿梭的氟离子电池受到人们的重视。综述近几年氟离子电池电解质和电极材料的研究进展,介绍固态氟离子电池和液态氟离子电池两类体系。从提高电解质离子电导率、改善电极/电解质界面结构、抑制电极材料溶解损失和调控电极材料结构与组成等方面,对高性能氟离子电池的发展进行展望。     

钴基氧化物热电材料研究现状与展望

综述了钴基氧化物热电材料国内外研究新进展,着重介绍NaxCo2O4热电材料的晶体结构、热电性能及制备方法;并对Ca-Co-O系列的CaCo2O4、Ca2Co2O5、Ca3Co2O6、Ca3Co4O9和Ca9Co12O28共5种不同结构的热电材料及Bi2Sr3Co2Oy、稀土系钴基氧化物RCoO3等氧化物热电材料作了介绍。还总结了为提高热电性能而进行的掺杂研究。最后展望了氧化物热电材料的发展前景。     

石墨烯在化学电源中的应用研究进展

石墨烯因其独特的电性能、化学性能、机械性能、热性能等而备受人们的关注,在各种化学电源中有着极大的应用潜力。简单介绍了石墨烯的制备方法,评述了近年来石墨烯在各种化学电源中的应用研究,并对石墨烯的应用前景进行了展望。     

Recent progress of resist and resist process in Japan

The procedure for pattern fabrication by photolithography is described, highlighting the need for resists that are sensitive to 436-nm and 248-nm light for submicrometer lithography. Recent developments in 436-nm resists are summarized. A two-layer resist process using silicon-containing resists and resists for Kr/F excimer lasers are discussed. The latter method, which uses 248-nm radiation, has great potential but requires considerable development before it becomes a practical method     

我国军用通信电池技术的最新进展

综述了我国近几年来军用通信电池,特别是镉镍蓄电池、金属氢化物镍蓄电池、高性能一次锂电池和锂离子蓄电池的最新进展与技术上所取得的重大突破。     

染料敏化太阳电池碳对电极研究进展

作为染料敏化太阳电池(DSCs)对电极Pt催化层的取代材料,低成本、来源广泛的碳材料展现出一定的应用前景。碳对电极组装的DSCs的转换效率已达到9.15%,其值接近Pt对电极DSCs的最高转换效率。主要对碳材料在对电极中的应用类型、涂层工艺以及组装后DSCs的光电性能、稳定性等进行阐述,同时对其存在的问题和发展趋势进行分析。     

Recent progress in sputtering PZT thin films for ferroelectric memories

Abstract

This paper describes amorphous Pb(Zr, Ti)O₃ (PZT) thin films deposited by cosputtering Pb(Zr_0.5 Ti_0.5)O₃ and PbO targets. By optimizing the amount of the excess Pb and the deposition temperature, PZT thin films with a single perovskite phase were obtained successfully on Ir substrates and Pt substrates at 520°C. 250-nm-thick PZT films crystallized by rapid thermal annealing (RTA) at 600°C for 20 s exhibited excellent ferroelectric properties: a coercive voltage of 1.0 V, a remanent polarization density of about 40 μC/cm², and a polarization switching endurance over 1x109 cycles. Although a heat treatment in a reductive ambient causes degradation of ferroelectric properties of PZT thin films, their degraded ferroelectric properties can be easily recovered from by a 1-min RTA in an oxygen at 400°C.     

直接甲醇燃料电池中阳极催化剂的研究进展

从铂基合金催化剂、以导电聚合物为载体的复合催化剂和含氮的大环配合物的开发等三个方面重点综述了直接甲醇燃料电池(DMFC)中阳极催化剂的研究进展,同时简要概述了DMFC中甲醇渗透对电池性能的影响及其解决方案。有关研究表明,合金组成、催化剂载体以及大环配合物对阳极催化剂的催化活性和稳定性有着直接的影响。尽管目前已经进行了大量的关于甲醇在阳极催化剂上的作用机理的研究工作,但还未形成共识。另外,利用新的合成方法制备高分散的催化剂也是阳极催化剂发展的重要方向。同时,还须从根本上解决甲醇在Nafion膜中的渗透问题。     

空间太阳电池发展现状及展望

电源系统是卫星的重要分系统之一 ,几乎所有的卫星均需配置一个合适而可靠的电源分系统。电源分系统在整个卫星系统中所占质量的比例是最高的[1] ,因此对电源系统的研究就非常重要。多数地球轨道卫星都采用太阳电池阵与蓄电池联合供电系统。空间的环境非常恶劣 ,温度起伏大 ,高能粒子多 ,使得工作在其中的太阳电池必须具备性能稳定和抗辐照等特性。文中对空间太阳电池系统的发展现状作了较为详细的介绍 ,比较分析了硅太阳电池与其它几种材料的空间太阳电池的发展现状和优缺点 ,得出了硅电池仍是目前空间应用的最佳选择的结论。还介绍了几种高效硅太阳电池及当前的发展水平 ,通过比较分析 ,提出了空间太阳电池的未来研究方向。     

MnBi永磁合金研究进展

Mn Bi合金具有显著的铁磁性及磁光效应,可用作永磁和磁光存储材料。Mn Bi磁性合金具有高的室温单轴磁各向异性和反常的正的矫顽力温度系数,有希望成为高温应用(~200℃)磁性材料而引起了广泛关注。但由于其相转变的复杂性,制备高纯度、高磁性能的Mn Bi合金仍存在一定的难度。近年来许多研究者对Mn Bi磁性合金的热处理工艺、制备工艺以及复合磁体等方面进行了一系列的研究。截至目前,已经基本可以批量化生产高纯高性能Mn Bi磁粉,同时所制备Mn Bi单相合金的最大磁能积(BH)max已经达到了8.4 MGOe,所制备Mn Bi复合磁体的最大磁能积(BH)max也达到了最高的18 MGOe。这些研究极大地促进了Mn Bi磁体的发展,为Mn Bi永磁体的工业化生产应用奠定了基础。本文综述了近年来高性能Mn Bi永磁材料的研究进展。     

电化学电容器电极材料研究现状

综述了当前就提高电化学电容器能量密度所取得的研究进展。并针对电极材料的不同改性方法及涌现出的新材料,详细介绍了各种电化学电容器的电化学性能。指出了电化学电容器在发展中面临的问题,并对其应用前景进行了展望。