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21.
Kuo‐Hsiung Wang Tzong‐Ming Wu Yeng‐Fong Shih Chien‐Ming Huang 《Polymer Engineering and Science》2008,48(9):1833-1839
The water bamboo husk is one of major agricultural wastes in Taiwan. In this study, the powder obtained from the water bamboo husk was added to poly(lactic acid) (PLA) to form novel reinforced biodegradable composites. Morphologies, mechanical properties, and heat resistance of these water bamboo powder reinforced composites were investigated. The results indicate that the char yields were increased as plant powder was incorporated to PLA. In addition, the mechanical properties were also enhanced due to the addition of powders. The increments of storage moduli of PLA were about 50–200%. Moreover, the increments of loss moduli of PLA were about 70–200%. On the other hand, the Tg of PLA was slightly decreased by the addition of powder, and this may improve the brittle characteristics of PLA. Furthermore, this type of reinforced PLA would be more environmental friendly than the artificial additive‐reinforced one. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers 相似文献
22.
地方热电联产企业发展对策的探讨 总被引:2,自引:2,他引:0
介绍了泰州热电企业的运行情况,分析了各热电厂在技术改造、扩大热用户和强化内部考核管理方面的措施,探讨了地方热电企业应采取的对策和发展思路。 相似文献
23.
Kow Ming Chang Yuan Hung Chung Gin Ming Lin 《Electron Device Letters, IEEE》2002,23(5):255-257
Studies the anomalous variations of the OFF-state leakage current (IOFF) in n-channel poly-Si thin-film transistors (TFTs) under static stress. The dominant mechanisms for the anomalous IOFF can be attributed to (1) IOFF increases due to channel hot electrons trapping at the gate oxide/channel interface and silicon grain boundaries and (2) IOFF decreases due to hot holes accumulated/trapped near the channel/bottom oxide interface near the source region. Under the stress of high drain bias, serious impact ionization effect will occur to generate hot electrons and hot holes near the drain region. Some of holes will be injected into the gate oxide due to the vertical field (~(V_Gstress V_Dstress)/T OX) near the drain and the others will be migrated from drain to source along the channel due to lateral electric field (~V_Dstress/LCH) 相似文献
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Monodisperse silica particles of about 0.3m diameter are suspended in methacrylate monomer using a carefully selected dispersant. Many steric dispersants are hydrocarbon chains with a reactive end-group. These are not effective as dispersants for silica in moderately polar solvents, such as esters and the methacrylate monomers. Good dispersion was obtained with a methacrylate polymer terminated by a chlorosilane end group. Settling or centrifugation of these unagglomerated dispersions gives well-packed particle beds. Polymerization of the surrounding monomer produces composite materials with high packing fractions and a high degree of regularity. Moduli and strengths of these composites are reported. 相似文献
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对乳白玻璃瓶表面产生条纹的原因进行分析,通过耐火材料选用、稳定熔制工艺、工作池中层取料和供料道加搅拌的方法消除条纹缺陷。 相似文献
29.
Yun-fei Liu Yi-nong Lu Ming Xu Liu-fei Zhoun 《Journal of the American Ceramic Society》2007,90(6):1774-1779
The molten salt synthesis (MSS) method is utilized to synthesize the anisotropic platelet Sr3 Ti2 O7 (S3T2) single-crystal particles. The aim of this study is to identify the essence of platelet Sr3 Ti2 O7 crystal growth and guide the synthesis of anisotropic platelet SrTiO3 crystals as well as various technologically important materials. Based on the results of X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy, the formation mechanism of platelet Sr3 Ti2 O7 crystals conforms to a nucleation–structure rearrangement–dissolution–diffusion in situ epitaxial growth mechanism model. First, SrCO3 reacts with TiO2 to form submicrometer SrTiO3 nuclei. Then, most of the nuclei surrounded by salt ions aggregate and rearrange to form a large SrTiO3 matrix. The structural rearrangement and the subsequent in situ epitaxial growth processes control the morphology, composition, and size of the final Sr3 Ti2 O7 crystals. In the synthesis process, the conversion between SrTiO3 and Sr3 Ti2 O7 is as follows: and the crystallographic orientation relationship between Sr3 Ti2 O7 and SrTiO3 in the interface is (100)S3T2 //{100}ST , (010)S3T2 //{010}ST , and (001)S3T2 //{001}ST . 相似文献
30.
现场总线技术在电力自动化中的应用 总被引:1,自引:0,他引:1
现场总线(Fieldbus)是当前自动化领域的热门话题,被誉为自动化领域的计算机局域网。信息技术的飞速发展.引起了自动化系统结构的变革,随着工业电网的日益复杂,人们对电网的安全要求也越来越高。现场总线控制技术作为一门新兴的控制技术必将取代过去的控制方式而应用在电力自动化中。 相似文献