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171.
To improve the durability of hydrogen storage materials against surface poisoning by impurity gases, effectiveness of Pd-coating layer prepared by using a Barrel-Sputtering System was examined for ZrNi powder. The effectiveness of Pd-coating was evaluated by activation temperature, at which Pd/ZrNi poisoned by air could be activated to absorb hydrogen. Characterization of Pd-coated ZrNi (denoted as Pd/ZrNi) by scanning electron microscopy, electron probe microanalysis and X-ray diffraction showed that a uniform Pd-coating layer was formed with the barrel-sputtering system. It was found that the poisoned Pd/ZrNi sample could be activated even at 423 K to absorb hydrogen at room temperature. This exhibits remarkable contrast to bare ZrNi, which could be only activated appreciably above 1073 K. It is concluded that the Pd-coating by barrel sputtering is quite effective to avoid the effect of surface poisoning of powdery hydrogen storage materials. However, the activation at excessively high temperature resulted in the loss of high activity to absorb hydrogen. It was concluded that this phenomenon was associated with reactions between Pd and ZrNi to form PdZr and other byproducts.  相似文献   
172.
我国石油开采与油井管生产概述   总被引:1,自引:1,他引:0  
概略介绍了我国石油开采及其专用管材的需求情况以及油井管的生产规划和要求,对发展国内油井管特别是焊接油井管生产提出了建议。  相似文献   
173.
Characteristic Anthocyanin Pattern from Onions and other Allium spp   总被引:3,自引:0,他引:3  
Three red onion (Allium cepa) cultivars, top onion (A. cepa var. vivi-parum), A. altaicum and chive (A. schoenoprasum) contained several or all of the following anthocyanins: 3-(6′-malonyl-3′-glucosylglucoside), 3-(3′,6′-dimalonylglucoside), 3-(6′-malonylglucoside), 3-(3′-malonyl-glucoside), 3-(3′-glucosylglucoside) and 3-glucoside of cyanidin. Trace amounts of two pelargonidin derivatives and the 3,5-diglucosides of cyanidin and peonidin were for the first time reported in red onion. Carbon NMR data showed that the sugars of the 3-(6′-malonyl-3′-glu-cosylglucoside), 3-(6′-malonylglucoside) and 3-glucoside of cyanidin were pyranoses. Substitution either by sugar or acid in the sugar 3-position of an anthocyanin has never been reported outside the genus Allium.  相似文献   
174.
本文分析了T/C府绸集色条花产生的原因。通过工艺条件和操作方法,染色条花疵病得到明显改善。  相似文献   
175.
本文旨在通过对玻璃钢管道及其标准的发展历史、产品特点、基本设计原理、质量影响因素及选用时应注意的事项等方面的介绍,使用户与工程设计人员对该产品有一个比较全面的了解,以便更好地选用并受益于这种管材。  相似文献   
176.
The GILDES computer model, incorporating Stumm's concept of proton- and ligand-promoted dissolution, has been used to simulate the exposure of copper at room temperature to 210 ppb sulfur dioxide and 80% relative humidity. The agreement is good between the calculations and laboratory exposures performed under these exposure conditions. Surface reactions are relatively more important at lower relative humidities and the dominant corrosion products formed are solid state Cu2SO3, CuSO3 and Cu2U. Free-radical redox processes are important participants and control the relative distribution of Cu(I)- and Cu(H)-containing corrosion products.  相似文献   
177.
一种碳-碳复合材料长寿命防氧化涂层的失效机制   总被引:2,自引:0,他引:2  
用液相法联合CVD法和硅化法制备了一种碳-碳复合材料复合梯度涂层,在此基础上对这种涂层在氧化过程中的失效机制进行了研究.结果表明:氧化层与液相层界面反应生成的气相产物是涂层失效的根本原因界面上气泡的不均匀形核、长大和破裂导致涂层表面出现孔洞.孔洞处气泡优先形核、长大和破裂并发展成为缺陷而使涂层失效  相似文献   
178.
It is demonstrated that glassy carbon powder can be thermochemically activated. During activation, a film with open pores is created on the glassy carbon particles. This film has a large internal surface area, which is accessible to liquids and gases. A simple model for the evolution of the internal surface area in glassy carbon powder during thermochemical gas-phase oxidation is also presented and compared with experimental data. Experimental results are in qualitative agreement with the model. We found that a sharp particle size distribution is desirable with regard to potential technical applications.  相似文献   
179.
延长Pd/C催化剂使用寿命的途径   总被引:6,自引:0,他引:6  
卢晓飞 《聚酯工业》2002,15(1):30-33
影响钯 炭催化剂使用寿命的因素主要有催化剂失活 ,运输、装填过程中的磨损 ,工艺操作条件等。延长催化剂的使用寿命的途径有正确的运输、装填方法 ,定期冲洗 ,定期碱洗和分阶段调整氢气加入量  相似文献   
180.
The Early Career Awards recognize the large number of excellent young psychologists. Recipients of this award may not have held a PhD for more than nine years. The areas considered in 1991 were animal learning and behavior, developmental, and personality. The winners for 1991 were Kent C. Berridge, Susan A. Gelman, and Randy J. Larsen. For each winner a citation, biography, and selected bibliography of their works are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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