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11.
A polyester (PE) based on the glycolyzed products of PET was prepared and added in different concentrations to a series of SBR/PVC blends. The addition of the polyester showed that all properties of SBR/PVC blends were improved by incorporation of PE. Highest mechanical strength values were obtained at a polyester concentration of 7.5 phr. Thermal analysis as well as dynamic mechanical properties of SBR/PVC blends after the addition of 7.5 and 10 phr polyester indicated one single glass transition temperature. The dielectric losses (?") were analyzed in the frequency domains in the two terms of Fröhlich related to the Maxwell Wagner effect and the orientation of the aggregates caused by the movement of the main chain. The permittivity (?') values were found to increase by increasing the polyester content. This increase was followed by a decrease in the ?" up to a 7.5 phr polyester content after which no pronounced change was noticed. 相似文献
12.
13.
YANG WeiFeng ZHANG QingZhao WANG MingGang & XIA Yang Key Laboratory of Microelectronics Devices & Integrated Technology 《中国科学:信息科学(英文版)》2011,(8)
In this paper, the cone-shaped patterned sapphire substrates (PSS) were etched by an inductively couple plasma with BCl 3 as the reacting gas. The influence of the operating pressure and the RF bias power on subtrenches of the cone-shaped PSS and the formation mechanism of subtrenches were investigated. The profiles of patterns were characterized by FESEM (field emission scanning electron microscope). It showed that the subtrench size varied with the operating pressure and the RF bias power. As the operatin... 相似文献
14.
采用介质阻挡放电(DBD)降解常压下流动态的邻二甲苯模拟废气,系统地考察了放电极值电压,气体的初始质量浓度、停留时间以及相对湿度等工艺参数对邻二甲苯降解的影响,并初步探讨了邻二甲苯的降解产物.实验研究结果表明:在7.0kV的放电极间电压下,邻二甲苯的初始质量浓度为1 500mg/m3,停留时间为9s,其去除率可达到80%以上.降解产物主要为CO2、H2O以及苯甲酸、苯乙酸、苯乙醛等有机物,并且经降解后产物的生物可生化性得到提高,因而为后续的等离子-生物法联合处理VOCs提供了依据. 相似文献
15.
在电火花加工的工作液中添加络合剂,使之与被蚀除的金属颗粒产生络合化学反应,生成可溶于工作液中的络合物。利用这种原理,可提高电火花加工性能,在小孔、深槽等加工应用中起到促进排屑的作用。 相似文献
16.
CHEN KenLe & ZHANG JinWen National Key Laboratory of Micro/Nano Fabrication Technology 《中国科学:信息科学(英文版)》2011,(2)
17.
Ivan Bozovic 《Journal of Superconductivity》1991,4(2):193-197
A novel optical method for accurate monitoring of the carrier densityN in layered conductors is introduced. It is applied to several cuprate superconductors, and it is found thatT
c
doesnot scale withN. However, if the closely spaced pairs or triplets of CuO2 planes were coupled together to act as distinct metallic slabs, the relevant variable could ben, theslab carrier density. Indeed, we found thatT
c
does scale nicely withn. This suggests that high-T
c
superconductivity is effectively a two-dimensional phenomenon; it can occur in a cuprate slab which is only one unit cell thick. Finally, estimates are obtained for the length scales of localization of charge carriers:d 8 Å andd
2 Å in all the cuprates under study. 相似文献
18.
利用宽频介电谱仪拓展热激励去极化电流模块测量介质材料的TSDC操作简单实用,它不仅容易把材料中的各种不同活化能或弛豫时间的荷电粒子区分开,并且能从TSDC谱中直接得出被测材料的介电性能以及相关微观参数,这为研究材料内部机理提供了一条捷径。 相似文献
19.
采用二次固相反应法制备Ba0.7Sr0.3TiO3介电陶瓷,研究了掺杂钴、钇离子对钛酸锶钡介电性能的影响。结果表明,陶瓷样品Y3+、Co3+的最佳掺杂浓度分别为0.04mol%和0.05mol%,最佳烧结温度为1340℃,样品的相对介电常数为4200,介电损耗(tanδ)为0.005。样品的结构为四方晶系,P4mm空间群。获得了高介电常数、低损耗的Ba0.7Sr0.3TiO3介电陶瓷。 相似文献
20.
The signals induced by an external electromagnetic field along a microstrip line on a multilayered dielectric substrate were studied. The main target of the work is not to introduce a new technique of study but to search for suitable combinations of the structural and geometrical characteristics of the printed geometry whereby the electromagnetic interference of the external field to the circuit would be reduced. This reduction is desirable in all modern applications. The results derived prove that this object can be achieved at high frequencies and when the substrate is multilayered. 相似文献