Evolutionary topology optimization for temperature reduction of heat conducting fields

This paper aims at developing an efficient finite element based computational procedure for the topology design of heat conducting fields. To evaluate the temperature change in a specific position, due to varying the conducting material distribution in other regions, a discrete temperature sensitivity is derived for an evolutionary topology optimization method. In the topology optimization of the conducting fields, the thermal conductivity of an individual finite element is considered as the design variable. By removing or degenerating the conductive material of the elements with the most negative sensitivity, the temperature objective at the control point can be most efficiently reduced. Illustrative examples are presented to demonstrate this proposed approach.     

Substrate treatment and drying conditions effect on the properties of roll-to-roll gravure printed PEDOT:PSS thin films

The optical, structural and electrical properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) thin films printed by roll-to-roll gravure have been investigated. Corona treatment has been applied to enhance the adhesion of PEDOT:PSS on PolyEthylene Terephthalate (PET) web. It has been found that there was a stronger in-depth surface modification of PET with the increase of corona efficiency; however, the adhesion of PEDOT:PSS was not actually affected. Also, Spectroscopic Ellipsometry and Atomic Force Microscopy have been used to extract information on the mechanisms that define PEDOT:PSS properties. The increase of the drying temperature of the PEDOT:PSS films has been found to reduce the remaining water inside the films and lead to the decrease of the PEDOT:PSS particles size.     

湿化学法制备ATO/TiO2复合粉体电阻率及导电机理的研究

采用湿化学共沉淀法,在TiO2颗粒表面包覆ATO制备ATO/TiO2复合粉体.研究了复合粉体的形态结构、ATO含量对ATO/TiO2复合粉体电阻率的影响,并对导电机理进行了讨论.研究结果表明,ATO以非晶态的形态靠范德华力与静电引力吸附在TiO2表面,ATO含量决定TiO2颗粒表面能否形成完整的导电网络基本框架.渗滤阈...     

碳质材料对磷酸铁锂正极材料物理和电化学性能的影响

通过综述碳质材料对磷酸铁锂(LiFePO4)电极材料物理和电化学性能的影响,评述了碳质材料在不同LiFePO4/C复合电极材料中的作用及其优缺点.指出:炭膜的原位包覆和模板炭的引入,限制了LiFePO4晶粒的生长,进而提高了电极材料的电导率;而导电炭和石墨烯的引入,则是直接提高了电极材料的电导率;有机结合这两种碳质材料的复合方式将会极大改善电极材料的电化学性能.但是,为了提高电极材料的体积能量密度及其振实密度,应该最大限度地降低碳质材料在LiFePO4/C复合电极材料中的含量.     

Photo atomic layer deposition of transparent conductive ZnO films

Low-resistivity ZnO films were grown by photo atomic layer deposition (photo-ALD) technique using diethylzinc (DEZ) and H₂O as reactant gases. Self-limiting growth was achieved for the temperature range from 105°C to 235°C. It was found that UV light irradiation was very effective to increase the electron concentration of the films and the electron concentration of 5 × 10²⁰ cm⁻³ was achieved even in undoped ZnO. Thus, the resistivity of the films grown with UV irradiation was one order of magnitude less than that grown without UV irradiation. The minimum resistivity of 6.9 × 10⁻⁴Ω cm was obtained by photo- ALD method without any intentional doping.     

银粉形貌及表面处理对导电胶性能的影响

利用四点探针和电子万能试验机分别测定了同种树脂体系中不同银粉形貌及银粉表面处理下导电胶的体积电阻率和剪切强度,探索了银粉含量、形状尺寸及表面处理对导电胶性能的影响规律.     

导电聚合物直接电镀技术

虽然传统的PTH（镀通孔）工艺十分成熟,应用广泛,但仍有很多不足之处。因此一些取代传统PTH工艺的直接电镀技术应用而生。导电聚合物直接电镀技术已经较为成熟,文中系统介绍了EcopactCP工艺的导电聚合物直接电镀技术。     

建筑结构胶粘剂及其应用与发展

1．建筑结构胶粘剂的发展国外建筑结构胶已有四十年的历史，目前全世界每年胶粘剂的总产量已达一千万吨，建筑行业用胶粘剂消耗量是仅次于木工的最大用户之一。美国1989年建筑用胶销售达9亿美元，日本1989年建筑胶粘剂用量达14万吨，比上一年增加约32％，全世界建筑用胶粘剂每年均以高于4％的速度在增长，并且朝着开发新品种（如水乳型、反应型、热熔型）、高性能、使用新工具和施工新技术的方向发展。建筑胶粘剂可分为非结构胶粘剂与结构胶粘剂两大类。非结构胶粘剂用量占了大部分，但随着建筑工程现代化的发展，硼年代后结构胶粘剂用量所…     

TAB OLB工艺在LCM制造中的应用

本文介绍了TAB器件及其制造工艺，通过讲述ACF特性，细致地阐述了TABOLB的工艺原理及参数设定方法，并对工艺中容易出现的不良现象进行了分析。     

Effect of Lamina Thickness on Parallel-to-Grain Strength in Small Douglas-Fir Samples

Timber has a rich history of use in bridge construction. Its small environmental footprint, pleasing aesthetics, long-term durability, and cost effectiveness assure its continued use for generations to come. That said, continued improvements in design, analysis, and construction with timber are highly sought. The inclusion of high-strength tensile-face laminations, such as fiber reinforced polymers, is increasingly common. This research investigated the impact of timber lamina thickness on axial compression strength parallel to the grain. Results showed that strength variability decreased with decreasing lamina thickness. This finding suggests that stronger and stiffer timber beams and stringers can be achieved by applying thinner wood lamina to the extreme compression faces. As such, the information contained herein can be used by glue-laminated-timber and fiber reinforced polymer/timber bridge designers to more effectively utilize wood as a structural material in bridges.