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介孔磷钨酸铯盐的液相组装及酸性研究 被引量:1
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作者 王美银 黄道丰 +5 位作者 陈欣 周俊夫 任远航 叶林 岳斌 贺鹤勇 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2021年第9期2734-2741,共8页
以磷钨酸(H_(3)PW_(12)O_(40))和氯化铯(CsCl)为原料,两亲型三嵌段共聚物F127为模板剂,按不同的Cs/P比制备了一系列介孔磷钨酸铯盐(Cs_(x)H_(3)−xPW_(12)O_(40),m-CsPW).通过X射线粉末衍射(XRD)、场发射扫描电子显微镜(FES⁃EM)、场发射... 以磷钨酸(H_(3)PW_(12)O_(40))和氯化铯(CsCl)为原料,两亲型三嵌段共聚物F127为模板剂,按不同的Cs/P比制备了一系列介孔磷钨酸铯盐(Cs_(x)H_(3)−xPW_(12)O_(40),m-CsPW).通过X射线粉末衍射(XRD)、场发射扫描电子显微镜(FES⁃EM)、场发射透射电子显微镜(FETEM)、N_(2)吸附-脱附测试和小角X射线散射(SAXS)等手段对所得样品进行了表征.结果表明,样品是由纳米微晶组装而成的晶态介孔材料.以三甲基膦为探针分子,通过^(31)P魔角旋转固体核磁共振波谱(^(31)P MASNMR)测定了样品酸处理前后的酸密度和酸强度.以5,7-二羟基-4-甲基香豆素的Pech⁃mann缩合反应为模型反应,考察了样品的酸性质与催化活性之间的关系. 展开更多
关键词 介孔多酸盐 ^(31)P魔角旋转固体核磁共振波谱 Pechmann缩合
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BISQ model based on a Kelvin-Voigt viscoelastic frame in a partially saturated porous medium 被引量:7
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作者 聂建新 巴晶 +3 位作者 杨顶辉 晏信飞 袁振宇 乔海鹏 《Applied Geophysics》 SCIE CSCD 2012年第2期213-222,236,共11页
Taking into account three important porous media mechanisms during wave propagation (the Biot-flow, squirt-flow, and solid-skeleton viscoelastic mechanisms), we introduce water saturation into the dynamic governing ... Taking into account three important porous media mechanisms during wave propagation (the Biot-flow, squirt-flow, and solid-skeleton viscoelastic mechanisms), we introduce water saturation into the dynamic governing equations of wave propagation by analyzing the effective medium theory and then providing a viscoelastic Biot/squirt (BISQ) model which can analyze the wave propagation problems in a partially viscous pore fluid saturated porous media. In this model, the effects of pore fluid distribution patterns on the effective bulk modulus at different frequencies are considered. Then we derive the wave dynamic equations in the time-space domain. The phase velocity and the attenuation coefficient equations of the viscoelatic BISQ model in the frequency-wavenumber domain are deduced through a set of plane harmonic solution assumptions. Finally, by means of numerical simulations, we investigate the effects of water saturation, permeability, and frequency on compressional wave velocity and attenuation. Based on tight sandstone and carbonate experimental observed data, the compressional wave velocities of partially saturated reservoir rocks are calculated. The compressional wave velocity in carbonate reservoirs is more sensitive to gas saturation than in sandstone reservoirs. 展开更多
关键词 BISQ model phase velocity attenuation coefficient VISCOELASTICITY water saturation CARBONATE tight sandstone
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Mesoporous polyoxometalate-based ionic hybrid as a highly effective heterogeneous catalyst for direct hydroxylation of benzene to phenol 被引量:4
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作者 Pingping Zhao Yunyun Zhang +2 位作者 Daokuan Li Hongyou Cui Lipeng Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期334-341,共8页
Self‐assembled mesoporous polyoxometalate‐based ionic hybrid catalyst,[PxyDim]2.5PMoV2,was prepared by combining p‐xylene‐tethered diimidazole ionic liquid[PxyDim]Cl2with Keggin‐structured V‐substituted polyoxom... Self‐assembled mesoporous polyoxometalate‐based ionic hybrid catalyst,[PxyDim]2.5PMoV2,was prepared by combining p‐xylene‐tethered diimidazole ionic liquid[PxyDim]Cl2with Keggin‐structured V‐substituted polyoxometalate H5PMo10V2O40.The obtained hybrid was shown to be a mesostructured and hydrophobic material with good thermal stability.In the H2O2‐based hydroxylation of benzene to phenol,the hybrid showed extraordinary catalytic activity and rate,and quite stable reusability.The unique hydrophobic properties and mesoporous structure of the hybrid were responsible for its excellent catalytic performance. 展开更多
关键词 POLYOXOMETALATE MESOPOROUS Benzene hydroxylation Heterogeneous catalyst PHENOL
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