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排序方式: 共有10000条查询结果,搜索用时 359 毫秒
931.
932.
介绍了城市集中供热管道用硬质聚氨酯泡沫的笥能和组合原料的工艺参数,并对保温管道的3种生产工艺如手工浇注法,一步法连续生产及二步法生产工艺进行了介绍了比较,给出了直埋供热管道保温层厚度的理论计算公式。 相似文献
933.
Yu Lin Hu Ming Lu Qiang Ge Peng Cheng Wang Ting Ting Lu 《Journal of Industrial and Engineering Chemistry》2010,16(4):615-619
As described in this article, 4,4′-bis(chloromethyl)biphenyl was obtained in 85% excellent yield by chloromethylation of biphenyl catalyzed by the recyclable temperature-dependant phase-separation system that comprised the dicationic acidic ionic liquid PEG1000-DAIL and methylcyclohexane under homogeneous catalysis in aqueous media. Compared to other synthetic methods, the novel method not only enhanced the yield, but also made the operating units easy workup. The mechanism of chloromethylation reaction and the process of catalysis in the thermoregulated ionic liquid bi-phase system were proposed. 相似文献
934.
在结合常规碳五分离工艺缺点及碳五热二聚特性的基础上,开发了在异戊二烯(IP)与环戊二烯(CPD)分离之后进行热二聚的后热二聚碳五分离新工艺,IP与CPD分离的关键为IP分离塔与CPD回收塔的组合。结果表明:后热二聚碳五分离新工艺具有更高的产品收率、更好的产品质量等诸多优点。 相似文献
935.
对镍盐化工污泥中镍的浸出条件进行了分析和考察,对浸出液中沉铁和沉镍的p H值进行了系统的分析;采用水洗工艺对粗产品中氢氧化镍杂质的去除效果进行分析,最终采用加酸溶解和蒸发结晶的方式制取硫酸镍产物。 相似文献
936.
In EAST TOKAMAK, resonant magnetic perturbation (RMP) coils, which are powered by RMP coil power supply (PS), are set to research edge localized mode, resistive wall mode and error field correction. In order to meet the requirements of fast response and output voltage ripple proposed by physical experimenters, the structure of multiple modules using cascaded carrier phase-shifted PWM H-bridges is adopted, which enhances the equal switch-frequency of the PS and improves the quality of output voltage. In the paper, theoretical calculation applying Fourier analysis is given to analyze its harmonics. Both simulation results on Matlab and test results of output voltage ripple show that the RMP coil PS can meet the requirements. 相似文献
937.
Yan Ge 《Journal of Experimental Nanoscience》2016,11(5):345-358
Tea tree oil (TTO) exhibits excellent broad-spectrum antimicrobial activity. In order to preserve it from the degradation in the presence of oxygen, light and temperature, TTO was encapsulated in liposomes (LTTOs) using the thin-membrane hydration and sonication method, and characterised by Zetasizer for size and size distribution, transmission electron microscope for morphology, zeta-potential for surface charge, entrapment efficiency and TTO release from the nanoparticles. The antimicrobial activities of phosphate-buffered saline solution containing TTO, unloaded liposomes and LTTOs suspension were determined by twofold serial broth dilution technique. The size of LTTOs was 75 nm and the encapsulation efficiency of 96.08% was obtained. LTTOs exhibited slow release of TTO and superior broad-spectrum antimicrobial effects compared with free TTO. Liposomes not only effectively encapsulated TTO to form a stable liposome suspension, but also enhanced inhibition and bactericidal effect on the TTO-tolerant strain. The liposomal systems carrying TTO may be a potential alternative for effective antimicrobial agents. 相似文献
938.
Dongpo Chen Lei Zhao Hongwei Diao Wenbin Zhang Ge Wang Wenjing Wang 《Journal of Materials Science: Materials in Electronics》2014,25(12):5322-5330
Four different low-temperature silver pastes were utilized to make metal grids by screen printing for silicon heterojunction solar cells. The rheological behaviors of the low-temperature silver pastes were characterized by viscosity test, thixotropy test, oscillatory stress sweep test and creep-recovery test. The correlationship between the screen-printing performance and the rheological properties was investigated. It was found that the shear thinning behavior and the thixotropy behavior of the silver pastes were desirable for the screen-printing process. An obvious viscoelastic behavior of the silver paste was also helpful for improving its printability. Further, good recovery and low creep and recovery compliances could minimize the printing defects and the tendencies to bleed out during the screen-printing, and thus increase the aspect ratio of the printed grids. 相似文献
939.
940.
介绍了-个采用PowerBuilder开发的提案管理系统.该系统采用客户端/服务器结构,分为用户管理、提案数据管理、任务数据管理、日志管理四个部分.描述了总体的设计思想、基本功能设计、数据库设计和关键技术.该系统能够帮助用户快速、方便的管理提案数据,在实际中得到了很好的应用. 相似文献