Ni3Al合金中晶界与位错交互作用的研究

运用嵌入原子法势函数和静态驰豫最陡梯度的计算方法,原子模拟了Ni_3Al合金中晶界与位错的交互作用.主要研究了晶界与位错交互作用的能量特征、晶界结构单元的畸变行为和晶界附近位错的核心结构,并分析讨论了各种因素对它们的影响以及与Ni_3Al晶界韧脆行为之间的关系     

Influences of dehydrating process on properties of ATO nano-powders

1　INTRODUCTIONCrystallineSbdopedtinoxide (ATO) ,cassiteritestructure ,isawidebandgapn typesemiconductor.Be causeofitsopticalproperty (transparentforvisiblelightandreflectiveforIR )andelectroconductibility ,goodchemicalandmechanicalstability ,ithasmanyapplica tions,suchastransparentconductiveelectrodes ,photo voltaicdevices ,photosensors ,catalyst,antistaticcoatingsandelectrochromicmaterials[14 ] .AvarietyoftechniqueshavebeenusedtoprepareATOsuperfinepowders ,someinvolvedryprocesses ,ot…     

化学还原法制备导电涂料用片状超细铜粉的研究

以CuSO4·5H2 O为原料 ,抗坏血酸为还原剂 ,NH3 ·H2 O为络合剂 ,将络合剂在反应温度加到CuSO4·5H2 O溶液中 ,再加入还原剂 ,制备了粒径分布为 1～ 10 μm的片状铜粉。探索与分析NH3 ·H2 O的用量、反应温度和CuSO4浓度对铜粉形貌及产率的影响。结果表明 :络合剂的使用是制备片状超细铜粉的关键 ,其与Cu2 + 形成络合物 ,减少溶液中游离Cu2 + 的浓度 ,控制铜的生成速度 ,并影响铜的成核和生长 ,最终形成片状铜粉。     

电磁屏蔽涂料的发展现状及趋势

电子产品的日益普及使得电磁干扰成为一个突出问题,应用电磁屏蔽涂料是消除电磁干扰简单而有效的方法,本文介绍了电磁屏蔽涂料的组成、效能评价方法、技术思想、存在的问题以及发展趋势。复合型以及水性屏蔽涂料具有广阔的研发前景,高效能、宽频带、寿命长的电磁屏蔽涂料将会受到市场欢迎。     

导电聚苯胺复合纤维的研制

利用氧化聚合法，在室温、常压下快速将苯胺聚合在极性纤维表面，从而赋予纤维优良的导电性能，其表面电阻达到１０￣３Ω／ｃｍ。同时对导电性能的耐洗牢度进行了初步研究。     

Conductive Papers Containing Metallized Polyester Fibers for Electromagnetic Interference Shielding

Conductive papers were developed for preventing or reducing electromagnetic interference (EMI), and their shielding efficiency was evaluated. This type of conductive paper consists of wood pulp, synthetic pulp and metallized polyester fibers (0.5–2.0 mm long and 14 m in diameter) whose surfaces are coated with nickel alone (Ni-PET) or copper and nickel double layers (Ni-Cu-PET) by electroless plating. In this report, the effect of the characteristics of these metallized fibers, such as their conductivity, geometry and the concentration of fibers in paper, which lead to high efficiency for shielding effectiveness is discussed. For instance, one of the conductive papers (80 g/m2) which was prepared by mixing 40% Ni-Cu-PET and 60% synthetic polyethylene pulp showed over 40 dB shielding effectiveness between 10 MHz and 1 GHz.     

金属闪光外墙乳胶漆的研制及性能研究

以丙烯酸酯及有机硅单体为原料合成了核-壳型硅丙乳液,用自制分散剂将闪光铝粉分散成水性闪光铝粉浆,并成功分散于硅丙乳液中,加入进口助剂,配制成水性金属闪光外墙乳胶漆.讨论了基料的玻璃化温度、单体的加入方式、引发剂、乳化剂、反应温度、聚合工艺和pH等对乳胶漆性能的影响.     

沥青混凝土心墙坝渗漏检测及防渗体系修复综述

针对部分沥青混凝土心墙坝出现渗漏情况,为判定沥青混凝土心墙坝渗漏的部位及通道,需采用多种检测方法对坝体渗漏情况进行综合分析和判定。列举了多个工程应用实例,对沥青混凝土心墙坝渗漏检测方法如水下声纳检测、孔内彩电观测、示踪连通试验、坝体内水位分析和物探检测,以及混凝土防渗墙和控制灌浆修复坝体防渗体系方案及其影响因素进行了综述,以期为类似工程提供借鉴。     

A Solder Alloy Filled Z-Axis Conductive Epoxy Adhesive

Epoxy adhesives filled with four different volume fractions of eutectic tin-bismuth solder alloy were prepared and the effect of filler content on the electrical and mechanical properties of these anisotropic electrically conductive adhesives was investigated. The results show that the adhesive containing the lowest amount of the filler alloy had the best combination of conductivity, insulation resistance and shear strength. The DSC-measurements suggested that the filler melts before the cure of the resin begins which allows the filler to wet and bond well to the conductors. This was verified by SEM/EPMA examinations. A temperature cycling test and high humidity, high temperature treatment were conducted on the best composite adhesive. The temperature variation had no effect on conductivity of the joints while humid and hot environment decreased the conductivity.     

核壳型二氧化钛复合纳米材料研究进展

核壳材料由中心核和外部壳层组成，因其组成、大小、结构的不同，性能优于普通材料。二氧化钛具有优异的光、电和化学等特性可作为理想的核壳材料。从二氧化钛作为核壳型复合纳米材料的核、壳及核壳结构的载体3个方面出发，介绍了核壳型结构的二氧化钛复合纳米材料的分类、制备、性质及应用概况，并对其发展前景及存在问题进行了简要概述。