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981.
全逆流混合澄清器在溶剂萃取厂中的应用   总被引:2,自引:0,他引:2  
付子忠 《铀矿冶》1992,11(2):46-49,15
本文综述了全逆流混合澄清器的结构特征、主要优点和在稀土分离、铀、钨及废水处理等领域的12个工厂应用的结果;并与普通混合澄清器进行了萃取级效率、溶剂夹带损失和经济效益对比。  相似文献   
982.
In this article, poly (dimethyl siloxane) (PDMS) porous beads were prepared by suspension polymerization method using n‐octane and carbon tetrachloride (CCl4) as diluents and pore formation agents. The apparent density, porosity and other characteristics were characterized. The absorption experiments showed that the porous PDMS beads exhibited more absorption capacity and faster absorption rate toward oils than the nonporous or oligoporous PDMS beads did, moreover they are of remarkable stability and recyclability, which could provide a path to absorb the oils floating on water. POLYM. ENG. SCI., 54:2965–2969, 2014. © 2014 Society of Plastics Engineers  相似文献   
983.
A slurry erosive wear apparatus developed by the authors has been used to test the erosive wear behaviour of selected metals in coal washing environments. The erosive wear test machine was employed to determine the effects of (1) carbon content in carbon steels, (2) chromium content in alloy steels, and (3) corrosion of aqueous solutions on the erosive wear behaviour of metals. The test results revealed that the carbon content in annealed carbon steels slightly affects the erosive wear resistance of metals, while the increase in chromium content of alloy steels apparently improves the erosive wear resistance of metals and, when a corrosion inhibitor is added to slurries, the erosive wear rates of metals reduces significantly. Two types of micro-mechanism were deduced from the observation of eroded surfaces by SEM: (1) local exfoliation, and (2) micro-cutting. The corrosion inhibitor can alter the micro-mechanism from local exfoliation to micro-cutting. The analyses show that the erosive wear of selected metals in slurries results from the synergistic effects of wear by solid particles plus fluid corrosion.  相似文献   
984.
汽轮机驱动给水泵应用与节能分析   总被引:1,自引:0,他引:1  
赵艳志  杜付 《发电设备》2006,20(1):45-46
介绍了汽轮机驱动给水泵的基本原理和适用条件,哈尔滨气化厂实际使用情况和经济效益分析,证实了汽轮机驱动给水泵的节能效果十分显著,可予以推广。  相似文献   
985.
多组分免疫传感是免疫分析领域的一个研究热点,具有分析通量高、所需时间短、样品消耗少、分析成本低等突出优点.目前多组分免疫传感多采用空间分辨或多标记物模式.该文综述了近十年来多组分免疫传感技术的进展及其应用,并对其发展前景进行了展望.  相似文献   
986.
付克勤  杨霁 《电工技术》2007,(10):63-64
介绍了10kV系统中一组采用四星形接线的TV发生爆炸经过,通过分析其爆炸的原因提出了解决措施.  相似文献   
987.
Chemical doping is favored by academia as well as industry because of its effectiveness in attuning to the properties of piezoceramics. Although significant progress has been made, few reports have focused on the role and overall effect of substituted ions. Based on the tendency of special crystals such as ZnO toward spontaneous growth, this study applies the concept of composite modulation to conventional doping; the CuO-modified 0.2Pb(Zn1/3Nb2/3)O3-0.8Pb(Zr1/2Ti1/2)O3 (PZN-PZT) system has been used for verification of the proposed method. The results show that copper ions enter the perovskite matrix to specifically replace the zinc ions causing lattice distortion and increasing the rhombohedral phase (RP) content. Furthermore, the substituted zinc ions enter the grain boundaries and grow into a secondary phase ZnO, based on their spontaneous-growth tendency; the induced heterogeneous interfacial effects lead to refinement of the domain size and enhancement of the interface polarization. The combined effects of the lattice substitution and composite modulation promote a significant improvement in the piezoelectric coefficient of the CuO-modified PZN-PZT system compared with its pure counterpart. The dual function of doping demonstrated in this study is expected to further contribute to the preparation and performance improvement of the other piezoelectric composites.  相似文献   
988.
谈计算机信息网络系统的防雷   总被引:1,自引:0,他引:1  
本文简要介绍了雷击的成因、种类,以及防雷原理,并特别针对计算机信息网络的防雷进行初步探讨。  相似文献   
989.
Pigeon Pea (Cajanus cajan (L.) Millsp.) is a common food crop used in many parts of the world for nutritional purposes. One of its chemical constituents is cajanin stilbene acid (CSA), which exerts anticancer activity in vitro and in vivo. In an effort to identify molecular targets of CSA, we performed a kinome-wide approach based on the measurement of the enzymatic activities of 252 human kinases. The serine-threonine kinase WNK3 (also known as protein kinase lysine-deficient 3) was identified as the most promising target of CSA with the strongest enzymatic activity inhibition in vitro and the highest binding affinity in molecular docking in silico. The lowest binding affinity and the predicted binding constant pKi of CSA (−9.65 kcal/mol and 0.084 µM) were comparable or even better than those of the known WNK3 inhibitor PP-121 (−9.42 kcal/mol and 0.123 µM). The statistically significant association between WNK3 mRNA expression and cellular responsiveness to several clinically established anticancer drugs in a panel of 60 tumor cell lines and the prognostic value of WNK3 mRNA expression in sarcoma biopsies for the survival time of 230 patients can be taken as clues that CSA-based inhibition of WNK3 may improve treatment outcomes of cancer patients and that CSA may serve as a valuable supplement to the currently used combination therapy protocols in oncology.  相似文献   
990.
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