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1.
半导体材料研究的新进展   总被引:7,自引:0,他引:7  
王占国 《半导体技术》2002,27(3):8-12,14
首先对作为现代信息社会的核心和基础的半导体材料在国民经济建设、社会可持续发展以及国家安全中的战略地位和作用进行了分析,进而介绍几种重要半导体材料如,硅材料、GaAs和InP单晶材料、半导体超晶格和量子阱材料、一维量子线、零维量子点半导体微结构材料、宽带隙半导体材料、光学微腔和光子晶体材料、量子比特构造和量子计算机用材料等目前达到的水平和器件应用概况及其发展趋势作了概述.最后,提出了发展我国半导体材料的建议.本文未涉及II-VI族宽禁带与II-VI族窄禁带红外半导体材料、高效太阳电池材料Cu(In,Ga)Se.CuIn(Se,S)等以及发展迅速的有机半导体材料等.  相似文献   

2.
国内外红外隐身材料研究进展   总被引:2,自引:0,他引:2  
从红外探测系统的探测方法和Stefan-Boltzmann定律两个方面分析红外隐身材料的隐身原理,得出红外隐身的主要措施有降低目标表面红外发射率和控制目标表面温度。综述了低发射率涂层材料、控温涂层材料、智能隐身材料和生物仿生隐身材料等四种红外隐身材料近几年的国内外研究现状。指出了目前红外隐身材料研究存在的问题,在此基础上,展望了红外隐身材料未来的发展方向。  相似文献   

3.
Biological organisms exist in an astounding array of habitats. The materials produced by these organisms correspondingly exhibit significant diversity in function and form. Highly ordered and structured biological materials have been the subject of intense scientific investigation, especially in the context of exploring possible models for functional materials. Biological materials lacking in organized structure, on the other hand, such as barnacle exoskeletons, have largely been ignored. Here disordered biological materials falling into four different classes are discussed: soft and organic, hard and organic, soft and a composite of organic and inorganic, and hard and a composite of organic and inorganic. Across the examples within each class of materials one can see disorder at different length scales providing increases in fracture resistance or flexibility, suggesting disordered biological materials have much to teach us in terms of materials design.  相似文献   

4.
随着军事探测技术的逐渐成熟,各种隐身材料都面临着巨大的挑战,尤其是单一隐身材料,所以兼容复合隐身材料就成了研究重点。本文从材料的角度上介绍了雷达、红外、激光及兼容隐身原理,揭示了兼容隐身的方法,对现有雷达红外、激光红外、激光雷达和雷达红外激光兼容隐身材料的研究现状与原理做了简述,并对未来兼容隐身材料的发展方向做了总结与展望,并指出质轻、料薄、智能、宽波带、强吸收是未来隐身材料发展的趋势。  相似文献   

5.
Our purpose was to obtain and characterize some collagen/hydroxyapatite (COLL/HA) hybrid composite materials with desired ceramic properties. The ceramic properties of these materials were achieved by combining two drying methods: controlled air drying at 30°C followed by freeze-drying. Through the function of the air drying times, the materials morphology varies from porous materials (when the materials are freeze-dried) up to dense materials (when the materials are air-dried), while the combined drying allows us to obtain an intermediary morphology. The composite materials intended to be used as bone grafts and in a drug delivery system were characterized by XRD, FTIR, SEM, and also by determining the ceramic properties by using the Arthur method. The ceramic properties of these COLL/HA composite materials vary in large range, for instance the density of the materials varies from 0.06 up to 1.5?g/cm(3) while the porosity varies from 96.5% down to 27.5%.  相似文献   

6.
随着红外探测技术的迅速发展,如何提高军事目标的红外隐身能力成为一个亟待解决的难题,研究红外隐身材料有着十分重要的意义.本文简要分析了红外隐身材料的隐身机理,综述了低红外发射率材料、控温材料、光子晶体以及智能红外隐身材料等4类红外隐身材料近年来的研究现状,并展望了红外隐身材料未来的发展趋势.  相似文献   

7.
镁基储氢材料的研究进展   总被引:1,自引:0,他引:1  
总结了近几十年来镁基储氢材料的发展情况,并对镁基储氢材料进行了合理的分类,将其分为镁单质储氢材料、镁基合金储氢材料和镁基复合材料储氢.总结了目前制备镁基储氢材料所用的主要方法,例如熔炼法、扩散法、机械合金化法、氢化燃烧合成法等.  相似文献   

8.
Structural and compositional diversities of proteins generate a number of functions for fabricating novel and advanced materials. Recent progress in protein engineering endows flexible approaches and new functionalities, which makes the fabricated materials potentially applicable in a broad spectrum of fields. Such engineering strategies by applying proteins alone or together with other molecules derive numerous functional materials such as patterned nanometal materials/nanometallic compounds, well-designed nanocomposites, etc. Advantages in materials’ tunability, property improvement (e.g., electronic and mechanical properties, etc.), functionalities, and biocompatibility have been demonstrated, thus providing alternatives to existing materials via conventional methods. This review summarizes and discusses the strategies of fabricating functional materials using proteins as the critical contributors. Benefiting from their versatility, proteins find their roles in engineering functional materials via acting as structure-control agents, reaction agents, and battery components, which are emphasized in this review. The strategies of each group of functions are specifically detailed. Properties of protein-engineered functional materials and their potential applications in the fields of microelectronics, energy storage and conversion, sensor devices, etc. are also reviewed.  相似文献   

9.
Circularly polarized luminescence (CPL) materials have received increasing attention in recent years. Amongst various CPL materials, circularly polarized phosphorescence (CPP) materials featuring long life-time represent a novel research frontier and exhibit promising applications in various fields. Herein, the state-of-the-art advances of CPP materials are systematically summarized, as classified into transition metal complexes, organic small molecules, polymers, and organic/inorganic hybrid materials. Besides, the recent applications of CPP materials in organic light-emitting diodes and encryption display are also summarized. Furthermore, the current challenges and future perspectives are put forward. It is expected that this review will offer more inspirations for the future rational design of advanced CPP materials, thus further promoting their future practical applications.  相似文献   

10.
电磁吸波材料研究进展   总被引:13,自引:1,他引:12  
阐述了常见的吸波材料种类及其特点,吸波材料的研究现状,重点介绍了纳米铁氧体吸波材料及其制备方法。笔者采用柠檬酸盐sol-gel法制得了均匀包覆铁氧体的空心微珠为基的复合材料,其吸波性能良好。最后指出吸波材料的发展趋势为纳米化、多元化和多介质化。  相似文献   

11.
锂离子电池正极材料研究进展   总被引:2,自引:0,他引:2  
主要介绍了传统锂离子电池正极材料的改性研究和新型锂离子电池正极材料的研究现状和发展方向。重点综述了正硅酸盐Li2MSiO4(M=Fe,Mn)类正极材料,含V的正极材料,有机物正极材料以及其他新型锂离子电池正极材料的研究现状和性能改进方法。  相似文献   

12.
Soft polymer materials, which are similar to human tissues, have played critical roles in modern interdisciplinary research. Compared with conventional methods, 3D printing allows rapid prototyping and mass customization and is ideal for processing soft polymer materials. However, 3D printing of soft polymer materials is still in the early stages of development and is facing many challenges including limited printable materials, low printing resolution and speed, and poor functionalities. The present review aims to summarize the ideas to address these challenges. It focuses on three points: 1) how to develop printable materials and make unprintable materials printable, 2) how to choose suitable methods and improve printing resolution, and 3) how to directly construct functional structures/systems with 3D printing. After a brief introduction on this topic, the mainstream 3D printing technologies for printing soft polymer materials are reviewed, with an emphasis on improving printing resolution and speed, choosing suitable printing techniques, developing printable materials, and printing multiple materials. Moreover, the state‐of‐the‐art advancements in multimaterial 3D printing of soft polymer materials are summarized. Furthermore, the revolutions brought about by 3D printing of soft polymer materials for applications similar to biology are highlighted. Finally, viewpoints and future perspectives for this emerging field are discussed.  相似文献   

13.
阐述了低k材料在IC电路中的作用及其性质,以SiO2、SiOF、SiOCSP、SiOCNSP、Si-OCSO五种材料为研究对象,分析了低k材料与Cu互连工艺的相互联系和作用。在Sikder和Kumar提供的声发射信号(AE)的在线监测图的基础上比较和分析了五种材料的硬度和模数值;根据Preston方程绘制九点测量数据图,发现前三种材料可满足抛光机理,而后两种的抛光行为更倾向于表面反应;根据五种材料抛光前后的实验数据表面形态图表,判断出抛光后材料粗糙度的走向。最后指出低k材料需要发展和完善的工艺及对抛光设备的进一步要求。  相似文献   

14.
综述了稀土上转换、光子晶体和有机体系光谱选择性激光隐身材料的光谱选择吸收机理,稀土上转换材料通过上转换原理、光子晶体材料通过膜系材料结构设计、有机体系材料通过特定官能团振动均可实现特定波段光谱能量的选择性吸收。分析了三种光谱选择吸收材料应用于激光隐身的可行性和激光隐身的实现方式,综述了材料的研究现状。指出,光谱选择性激...  相似文献   

15.
传统的电工材料主要是指电工产品中常用的导体材料、半导体材料、磁性材料以及电工绝缘材料等,然而随着社会的进步和科技的发展,新型高性能的电工材料因其优异的性能,给电工行业注入了新鲜的血液。尤其是它在军民两用高科技领域中的应用,有着出色的表现,同时,也在越来越多的领域中有着广泛的应用背景。  相似文献   

16.
数字电视整体转换中机房技术档案是至关重要的资料,必须及时准确记录各种网络资源的现有情况,才能准确地将模拟信号小区整体顺利切换到数字电视网络,避免信号质量下降、停播等恶劣影响。整理好机房档案是快速准确的处理各种紧急故障,提高操作效率的关键。机房的档案资料主要包括:机房的土建资料,机房供电系统资料,机柜安装资料,机房设备安装资料,机房信号覆盖范围网络资料等。  相似文献   

17.
首先介绍了国内外的几种微波衰减材料,同时分析了我所正在使用和研究的几种衰减瓷;其次介绍了波导传输反射法测量微波衰减材料的高频电磁参数,以及国内其它单位和国外的测量水平状况;再次,通过介绍衰减器微波吸收特性的CAD,对衰减瓷在使用中的不匹配问题进行了讨论;最后结合笔者的认识,讨论了今后微波管用衰减材料的研究方向。  相似文献   

18.
材料是在社会改革与进步中具有重要的作用,不仅使其物质基础,还是社会进一步发展的先导.在现代化科学技术的发展中,新材料技术得到较好的发展.并且,传统产业技术的发展与完善,也需要新材料技术的支持.我国对新材料的研究比较重视,在科技发展的规划中均得到体现.新材料的科技发展能够为我国的国民经济与社会的发展提供较好的依据,因此需要对新材料科技发展进行详细的分析,以便促进其发展.本文就新材料科技发展的重要性进行阐述,并对其发展趋势进行分析,从而探讨新材料科技发展的措施,有效的促进新材料科技发展水平的提高,为了我国经济与社会的发展提供贡献.  相似文献   

19.
余晨辉  沈倪明  周勇  成田恬  秦嘉怡  罗曼 《红外与激光工程》2022,51(7):20220288-1-20220288-10
光电探测器在通讯、环境、健康和国防等日常生活及国家安全等领域中应用广泛。随着时代的发展,对光电探测器在灵敏度、响应速度及波长范围等方面的性能要求与日俱增。低维材料独特的电学及光电特性使其在光电子器件领域具有重要的应用前景。为了充分利用低维材料的优势,克服其暗电流大、吸收率低的不足,研究人员提出将铁电材料与低维材料结合,利用铁电材料的剩余极化作用形成强局域场调控载流子浓度以提高低维材料的光电探测能力。文中总结了近年来铁电局域场增强低维材料光电探测器的研究成果,介绍了铁电材料对一维纳米线、二维材料以及低维结型器件的调控和性能提升方面的相关研究。最后,对铁电局域场增强低维材料光电探测器的发展趋势进行了简要的总结和展望。  相似文献   

20.
Advanced fusion devices will require that materials in various applications perform adequately under combinations of thermal and mechanical loads, electric and magnetic fields and neutron radiation. This article illustrates several aspects of materials technology for fusion by focusing on three major components-first wall structures, blankets, and large superconducting magnets. In describing the first wall, with armor and limiters, the central theme is potential effects from the severe operating environment which includes intense surface heat and bombardment by energetic atoms and high-energy neutrons. In the respective sections on blanket materials and on superconducting magnets, compatibility among materials and fabrication requirements are emphasized. While the mechanical, electrical or neutronic properties of materials can fulfill the primary performance requirements in specific materials applications, overall system requirements such as those for compatibility and appropriate fabrication techniques must also be satisfied in selecting and developing materials.  相似文献   

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