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151.
高职院校用人机制改革是各项改革中的重中之重,也是高职院校改革是否成功的重要标志之一。实施用人机制的改革就是要搞活用人机制,加大二级分院用人的自主权,引进企业的优质资源,专任教师与兼职教师相结合,通过"混编师资团队"建设完善"双师结构"师资队伍建设,从而提高人才培养质量。  相似文献   
152.
The mixed matrix membranes (MMMs) consisting zeolitic-imidazolate framework-8 (ZIF-8) nanoparticles in a polymer have been of considerable interest in separation applications. The fillers used are mostly synthesized using the solvothermal method. In this study, the ZIF-8 nanoparticles were synthesized using a solvent-less and salt-free mechanochemical method and were added to 6FDA-TrMPD polyimide to prepare MMMs. The single gas permeation of C3H6 and C3H8 through the MMMs was investigated. The C3H6 permeability and C3H6/C3H8 ideal selectivity of a 20 wt% mechano-synthesized ZIF-8/6FDA-TrMPD MMM were 70% and 32% higher than those of the neat polymer membrane at 0.1 MPa and 308 K, respectively. The C3H6/C3H8 separation performance of the mechano-synthesized ZIF-8 MMM was similar to that of the conventional solvothermal-synthesized ZIF-8 MMM. This separation performance was in good agreement with the Maxwell model. Temperature and pressure dependence analyses confirmed that the mechano-synthesized ZIF-8 nanoparticles acted as molecular sieves in the MMMs for the C3H6 and C3H8 permeation.  相似文献   
153.
Mixed matrix membranes (MMMs) were prepared by solvent evaporation method using Pebax-1074 polymer as matrix and inorganic zeolite SAPO-23 as dopant. The morphology, surface functional groups, microstructure, thermal stability, and separation performance of MMMs were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and gas permeation, respectively. The effects of dopant loading amount, permeation temperature, and permeation pressure on the structure and properties of MMMs were investigated. The results showed that the introduction of SAPO zeolite reduced the crystallinity of the MMMs and improved the CO2/N2 selectivity. Under the conditions of 30°C and 0.15 MPa, the MMMs prepared by incorporating with 5% SAPO zeolite in content exhibited the highest CO2/N2 selectivity of 72.0 together with the CO2 permeability of 98.2 Barrer.  相似文献   
154.
This article investigates the prediction of the crack growth angle of an existing internal crack under mixed mode loading at the crack tip for an unfilled ethylene propylene diene terpolymer rubber (EPDM). For the realization of mixed mode loading, the cracks of the uniaxial loaded specimens were oriented with different angles to the loading direction. The energy density factor was used as a potential criterion for determining the crack growth angle. The determination of the strain energy density factor was carried out simulatively in Abaqus. The second-order Ogden model was used to describe the rubber-like material behavior. The relative local minimum of the strain energy density factor provides the possible growth angle. The experimental investigations show that the initial cracks grow orthogonally to the loading direction for the different crack orientation angles. For the crack orientation angle parallel to the load direction, the crack growth was observed because the strong stretching of the specimen caused strong necking in the crack region. The crack growth for the remaining crack orientation angles were induced due to shear loading at the crack tip. The predictive angle of different crack orientation angles shows very good accordance to the measured crack growth angles.  相似文献   
155.
崔声睿  董林涛  金永成  向兰 《化工学报》2021,72(12):6380-6387
高性能、高安全储能电池的迫切需求加速了橄榄石型高电压正极材料的研究步伐。为了改善高电压磷酸钴锂(LiCoPO4)的综合电化学性能,采用溶剂热法研究了溶剂比、过渡元素(Fe、Mn)单掺杂和双掺杂(掺杂元素总量占10%)对正极材料形貌、尺寸、反位缺陷和电化学性能的影响。结果表明,当溶剂比为2.3时,未掺杂LiCoPO4在0.1C下表现出163.1 mAh·g-1的最高理论比容量;双掺杂LiCo0.9Mn0.05Fe0.05PO4正极材料具有突出的循环性能,在0.5C电流密度下,循环100圈后的容量保持率为78.9%,循环稳定性得到明显改善。  相似文献   
156.
超声磨料混粉电火花复合加工的研究   总被引:4,自引:2,他引:4  
阐述了超声磨料混粉电火花复合加工基本原理和基本设备,在试验研究的基础上对加工参数进行详细的讨论,分析了主要参数对表面粗糙度的影响。  相似文献   
157.
晶体取向和载荷模式对Ni3Al合金单晶体疲劳行为的影响   总被引:2,自引:0,他引:2  
张广平  王中光 《金属学报》1997,33(10):1009-1014
在名义Ⅰ型和Ⅰ/Ⅱ复合型载荷下研究了晶体取向和加载模式对Ni3Al合金单体疲劳开裂行为的影响。结果表明:疲劳开裂行为强烈地依赖于晶体取向和加载模式。在单晶体中,站劳裂纹总是沿着具有最大切应力的滑移须开裂。根据单晶体的实验结果,解释了用三种主要的复合型断裂准则所预测的多晶体在复合型加载下的疲劳开裂行为。  相似文献   
158.
RuTiSnMn/Ti阳极的电化学性能   总被引:2,自引:0,他引:2  
热分解制备了RuTiSnMn/Ti阳极,在4mA/cm^2的电流密度下进行了恒电流试验。通过循环伏安法和交流阻抗谱研究了阳极在35g/LNaCl溶液、20g/LNaOH溶液和模拟孔隙液中的电化学行为.利用EsEM对阳极失效前后的微观形貌进行了观察,结果表明:阳极具有优良的耐析氯、氧反应能力;钛基体逐渐形成TiO2的钝化膜使阳极的氧化物膜电阻增大,活性组元的消耗使法拉第电荷传递电阻增加,这两者最终导致阳极失效。  相似文献   
159.
朱应宝 《轻金属》2007,(3):17-19
本文介绍了碳分、种分工艺对精液硅量指数A/S的不同要求,认为种分精液单独生产是很有必要的.本文从理论上分析了目前所应用的脱硅工艺,提出了一种常压生产种分精液的方法-常压混合脱硅工艺,并对某厂采用此工艺进行种分精液生产的情况进行了简单的介绍.  相似文献   
160.
The effect of minor addition of -Al2O3 dispersoids on the sulfidation behavior of Fe-25Cr-20Ni was investigated over a range of pO2, 1.13×10–20 to 1.18×10 ****–22 atm. at constant pS2=1.22×10–8 atm. Fe-25Cr-20Ni and Fe-25Cr-20Ni 1.5 Al2O3 with and without preformed oxide scales were exposed to bioxidant gas mixtures H2/H2O/H2S/Ar at 700° C. Both isothermal and cyclic exposures were included. Scales were characterized by a combination of several surface analytical tools. A remarkable improvement in sulfidation resistance is observed in Fe-25Cr-20Ni-1.5Al2O3 under the conditions investigated here. This is attributed to the ability of the alloy to form and maintain a predominantly Cr2O3 scale with reduced Fe-diffusion and content. Possible scientific reasons for such improvement are discussed. The base alloy, Fe-25Cr-20Ni, fails to develop and retain such a Cr2O3 scale and undergoes sulfidation within a few minutes of exposure. The scale breakdown process by sulfidation is explained qualitatively. Experimental evidence suggests that sulfur in the environment enhances Fe-diffusion and content in the scale.  相似文献   
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