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91.
92.
敖包塔-葡萄花油田钻遇扶杨油层FⅡ油层组有效孔隙度主要分布在10%~15%之间,平均为12.6%;空气渗透率一般分布在0.1~10×10-3μm2之间,属低孔、特低渗透性储层。通过对选用7项宏观参数与7项微观参数确定储层综合评价参数并建立分类标准,确定出每个评价参数的分级标准,将敖包塔-葡萄花油田FⅡ油层组的储层分为四类,其中Ⅰ类最好,为低渗透储层;Ⅱ类次之,为特低渗透储层;Ⅲ类再次之,为超低渗透储层;Ⅳ类储层最差,为极差储层。依据专家经验及大量反复实验的结果上确定了权重系数,预测了FⅡ油层组的储层有利区带,结果表明敖包塔-葡萄花油田FⅡ油层组以Ⅰ类储层和Ⅱ类储层区为主,其中最有利储层区(Ⅰ类储层区)主要呈条带状分布于研究区北部的葡332~葡54~葡115-51、葡31、葡462、敖10等井区。 相似文献
93.
In recent years, research on coupled degradation of Nafion® membrane in polymer electrolyte fuel cell has generated huge interest among the scientific community. The coupled phenomenon behind the premature failure of fuel cell membranes in terms of its degradation is not well established. As the researches on this are in its adolescence, we try to provide some significant answers to the degradation phenomenon in terms of mechanically stimulated chemical degradation of the membrane. While the basic concept heavily relies on accurately modeling the membrane for its mechanical response to obtain molecular chain stretch, the results are utilized by the modified chemical rate equation for unzipping degradation mechanism. This article addresses significant degradation issues such as localized membrane thinning and pinhole formation, and inhomogeneous damage patterns in membrane electrode assembly in terms of mechanically induced accelerated chemical degradation of the membrane. 相似文献
94.
For improving stability without sacrificing ionic conductivity, ionically cross‐linked proton conducting membranes are fabricated from Na+‐form sulfonated poly(phthalazinone ether sulfone kentone) (SPPESK) and H+‐formed sulfonated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (SPPO). Ionically acid‐base cross‐linking between sulfonic acid groups in SPPO and phthalazone groups in SPPESK impart the composite membranes the good miscibility and electrochemical performance. In particular, the composite membranes possess proton conductivity of 60–110 mS cm−1 at 30 °C. By controlling the protonation degree of SPPO within 40–100 %, the composite membranes with favorable cross‐linking degree are qualified for application in fuel cells. The maximum power density of the composite membrane reaches approximately 1100 mW cm−2 at the current density of 2800 mA cm−2 at 70 °C. 相似文献
95.
M. G. Roig J. F. Bello S. Rodriguez J. F. Kennedy D. W. Taylor 《Polymer International》1996,39(1):17-30
Alkaline phosphatase from human placenta has been chemically immobilized on a hydrophilic cross-flow microfiltration membrane made from poly(vinylidene difluoride) (PVDF) derivatized with 1,1′-carbonyldiimidazole. The physicochemical characterization of the immobilized biocatalyst paid special attention to the irreversibility of the bonding of the enzyme to the support, the effects of pH, temperature and ionic strength on this activity, the existence of limitations of internal and external diffusion for H+, substrate and/or products, and the kinetic behavior (intrinsic and/or effective) of the immobilized enzyme. With respect to enzyme stability, patterns of hysteresis or memory are proposed, to account for a catalytic activity affected by previous experimental events and situations. The intrinsic kinetic behaviour, rate versus substrate concentration in the absence of diffusional restrictions, was analysed graphically and numerically (by non-linear regression and by utilizing the F statistical test for model discrimination), postulating a minimum rational rate equation of 2:2 degree in substrate concentration. In concordance, a mechanistic kinetic scheme for the catalytic enzyme action has been postulated. 相似文献
96.
Polyethylene-based ionomers, due to the presence of ionic aggregates, display a time-dependent crystalline morphology if submitted to thermal treatments. As a consequence gas permeability, which is strongly affected by physical morphology, is also found to be time dependent in previously thermally treated ionomer samples. The effect of sample exposure at 65°C and of successive ageing at 35°C on gas transmission properties of three different ethylene– acrylic acid ionomers (characterized by a different amount of acrylic acid groups, percentage of neutralization and type of counterions) has been investigated. In particular the changes in oxygen and carbon dioxide permeabilities due to thermal treatments at 65°C and subsequent ageing at 35°C have been monitored. X-Ray diffraction analysis and differential scanning calorimetry have been used to elucidate these changes in transport properties. 相似文献
97.
98.
优良的水利性能和耐久性是聚丙烯长丝土工织物在水利工程中长期稳定服役的关键,但相关研究数据的缺乏限制了对此类织物的深入理解及产品优化。通过研究不同单位面积质量和添加/未添加抗老化母粒织物的水利性能和耐久性发现:织物的水利性能,随单位面积质量增加而降低;高单位面积质量的织物皮层降解,但中间仍有未降解芯层,表现出耐久性增加的效果;同时,抗老化母粒的添加使织物水利性能稍有降低,但耐久性会显著升高,这归因于抗老化母粒具有阻止羰基形成、捕获自由基和分解过氧化物等作用。该研究为聚丙烯长丝土工织物的基础研究和实际应用提供了关键数据支撑。 相似文献
99.
100.