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研究添加不同含量的Ag对CP276合金的拉伸性能和时效组织的影响。对拉伸强度、延伸率测试及透射电镜观察表明:0.11wt%加入可促进T1相析出,使合金强度值升高;0.35wt%Ag的加入可在时效前期生成富Ag、Mg的稳定的GP区,从而降低合金中Cu的固溶度,阻碍T1相析出,时效后期,GP区分解,生成大量T1相,使合金强度值显著升高。 相似文献
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移动位置业务是移动通信网络的一项特色增值业务.将成为今后几年的业务增长亮点之一。中国联通总部的增值业务部于2002年采用集中设置方案,进行了CDMA位置服务系统一期工程的建设。本地定位平台建立于中国联通CDMA位置服务系统基础之上.其功能由以下的一项或多项组合而成:门户功能、中间件功能、GIS系统的的功能和对本地的CP进行管理和计费的功能。 相似文献
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A different newly designed cationic exchange polymer membrane and anionic exchange polymer membrane were introduced, and also the transport properties of these polymeric membranes were investigated in this study. The transport properties of these polymer membranes in contact with ferrocene redox derivatives were estimated by using electrochemical techniques such as cyclicvoltammetry, chronopotentiometry, and chronoamperometry techniques, respectively. The used ferrocene redox substances, which have different functional groups, were (Ferrocenylmethyl) trimethylamonium iodide, FcMA, Ferrocenedimethanol, FcDM, and Ferrocene carboxylic acid, FcCA. It indicated that the performance of a membrane depended on the content of polymer gel, anionic exchange polymer site (20 wt % and 50 wt %) or cationic polymer exchange site (20 wt % and 50 wt %), and the efficiency of the functional groups of cationic and anionic exchange polymer site as well. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Different routes for immobilization of TiO2 on conducting substrates were compared to find active and stable photocatalysts, which could either be operated in open circuit (photocatalysis) or with applied electric potential (photoelectrocatalysis). The advantage of applying an electric potential was investigated. Polarization curves and photoelectrochemical degradation reactions served to characterize catalysts and to find a way of predicting the optimum synthesis conditions. The difference between front side (EE) and back side (SE) illumination is discussed as a function of layer thickness, as well as the influence of oxidizable substance concentration on photocurrents. Stability of catalysts was investigated in repetitive degradation experiments. 相似文献
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概述了世界银行推进中国清洁生产项目中10家化工企业的清洁生产审计结果,总结分析了化工企业实行污染预防持续发展的策略,并对我国化学工业实现清洁生产提出了具体建议。 相似文献
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The pedicel, nest paper, and larval silk ofPolistes annularis nests were analyzed by high-resolution solid-state [13C]NMR. The pedicel was found to have a high nitrogen content (11%), and the NMR spectra indicated that it is a mixture of carbohydrate and protein. The pedicel protein has an amino acid composition that is very rich in glycine, alanine, serine, and proline (67% of identified residues), similar to that of some insect silks. Solid-state [13C]NMR indicated that the nest paper is composed predominantly of cellulose. Silk, spun by matureP. annularis larvae, was shown by [13C] NMR and amino acid analysis to be a protein very high in serine and alanine (53%), but the amino acid composition is distinct from that of the pedicel protein. 相似文献
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符彦青 《水电自动化与大坝监测》2011,35(4):45-46,49
分析了广州蓄能水电厂B厂由于高压气机及高压气系统效率降低导致调相压水周期过长,无法及时转入抽水调相(CP)工况运行的原因。通过处理压水管路漏气点、高压气机漏气、漏油点及将备用高压气机投入运行的技术改造,提高了高压气系统运行效率,满足及时启动CP工况的系统要求。该技术改造缩短单次CP启动高压气机运行时间,实现了高压气系统节能运行,具有一定工程有效性。 相似文献
10.
Penmatsa Krishna Kanth Varma Nagesh Kallollu Narayanaswamy 《International Journal of Communication Systems》2023,36(8):e5460
This communication presents a compact field de-correlation lines integrated dual band with dual-polarized (LP & CP) multiple-input multiple-output (MIMO) antenna for the fifth generation (5G) sub-6-GHz wireless communication systems. Dual working bandwidths, smaller interelement gaps, and superior isolation within the MIMO components are the distinguishing characteristics that give the proposed MIMO system an aspect of novelty. The modeled MIMO antenna has compact configurations of 20 × 21 × 0.8 mm3. The unit cell consists of a microstrip feed line with optimized rectangular slots branches etched from the radiated patch. The MIMO module is generated by the antiparallel replication of a single unit cell. To enhance the isolation, two rectangular slots are incorporated on the patch between the unit elements, which act as field de-correlation lines. The MIMO identity is supported by diversity performance calculations in terms of ECC, DG, and TARC. Simulated and measured counterparts are found in the agreement. 相似文献