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31.
功能化的酸性离子液体 总被引:49,自引:4,他引:45
围绕着功能化酸性离子液体这一主题,对新型Lewis,Bronsted酸性离子液体、离子液体的酸性测定以及酸性离子液体在异丁烷/丁烯烷基化反应中的应用进行了介绍和评述;提出了由新型酸性离子液体的合成、其酸性的表征及其催化性能的评价3方面有机地构成了研发酸性离子液体参与的工艺技术的良性过程;明确了“功能化”的涵义;展望了酸性离子液体巨大的工业应用前景。 相似文献
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The effect of tris(methoxy diethylene glycol) borate (TMDGB) on the coordination structure between ethylene carbonate (EC) solvents with high permittivity and ClO4− anions has been investigated by using a Fourier transform infrared (FT-IR) spectroscopy. The results of FT-IR analyses manifested that the boron atom of TMDGB anion receptor forms the complex with ClO4− anions. Even though Lewis acid-base interaction between the TMDGB anion receptor and ClO4− anions in the electrolyte solution lead to the prominent enhancement of both the dissociation degree of lithium salts and the lithium ion transference number, the ionic conductivity of the EC-based electrolyte solution decreased due to the trap of ClO4− anions by introducing the TMDGB anion receptor.The electrochemical stability of gel polymer electrolyte based on semi-interpenetrating network (IPN) structure with tris(pentafluoro phenyl) borane (TPFPB) or TMDGB anion receptor was obviously improved. 相似文献
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Reviews the book, Lewis M. Terman: Pioneer in psychological testing by Henry L. Minton (see record 1988-98726-000). Lewis Terman was one of the leading pioneers in the development of clinical tools and studies of individual differences. In the Preface to his book, Minton acknowledges that Terman was as controversial as he was influential and states that his biography seeks to provide a balanced view of Terman's life and works. As readers of this comprehensive volume will quickly find, Minton has been eminently successful in achieving this goal: His book not only highlights Terman's accomplishments, which were many, but also describes his shortcomings which, though fewer, were not nonexistent. Overall, Minton provides an extremely interesting, well-written, and probing account of the positive and the less-positive facets of his subject, both as a scientist and as a man. The book contains 11 chapters, describing Terman's life from his early years through his illustrious career at Stanford, up to his death in 1956, a month short of his 80th birthday. Throughout, Minton shows how Terman's upbringing, education, and the times and society in which he was raised contributed to shaping the person he was to become. Minton's biography of Terman, based primarily on an exhaustive reading of Terman's professional and personal papers and supplemented with interviews with former students and colleagues such as Nancy Bayley, Lee Cronback, Ernest Hilgard, and Robert Sears, and with members of Terman's family, provides a detailed and fascinating portrait of one of the major figures in psychology. The book's strengths are its consistently objective appraisal of its sometimes controversial subject, the scope of its coverage, the extensive documentation of its sources, and Minton's ability to set or to describe each of Terman's activities and the events in his life in their appropriate professional or social context. Readers from many walks will find this book interesting, informative, and well worth reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Akihiro Orita Shoko Tanabe Tatsuhiko Ono Junzo Otera 《Advanced Synthesis \u0026amp; Catalysis》2010,352(9):1419-1423
Fluorous distannoxanes (XRf2SnOSnRf2X)2⋅n H2O (Rf=C6F13C2H4) ( 1 : X=C8F17SO3, n=10; 4 : X=Cl, n=0) ( 1 ) catalyze the Mukaiyama aldol reaction and the allylation of aldehydes with tetraallyltin at room temperature in fluorous/organic biphasic solvent systems, in which the reactions proceed more rapidly than in a single organic or fluorous solvent. Due to the unique surface activity of 1 , the catalyst, organic substrate(s), and reagent(s) are distributed in both organic and fluorous phases to facilitate smooth reactions. Upon dilution with toluene after the reaction, the catalyst concentrates to the fluorous phase, while the organic substances migrate to the organic phase to effect facile catalyst recovery and recycling. By virtue of such a unique solvophilicity, a new version of fluorous biphase technology has been developed. 相似文献
37.
Effect of Newtonian Heating and Thermal Radiation on Heat and Mass Transfer of Nanofluids over a Stretching Sheet in Porous Media 下载免费PDF全文
Laminar boundary layer slip flow from a stretching surface in a nanofluid‐saturated homogenous, isotropic porous medium is studied numerically. A Newtonian heating boundary condition in the presence of thermal radiation is incorporated and a Darcy model utilized for the porous medium. The model used for the nanofluids include the effects of Brownian motion and thermophoresis. A group theoretical analysis is conducted to generate similarity transformations. The governing transport equations are nondimensionalized and rendered into a set of coupled similarity ordinary differential equations using similarity transformations. The transformed equations are then solved using the Runge–Kutta–Fehlberg fourth‐fifth order numerical method with shooting technique. It is shown that the physical quantities of interest depend on a number of parameters. The results are presented in tabular and graphical forms. Comparison of the present numerical solutions with published work shows very good agreement. The study finds applications in high‐temperature nanotechnological materials processing. 相似文献
38.
该文研究2-巯基嘧啶(2-MP)对三元阳离子钙钛矿太阳电池光吸收层与空穴传输层的界面进行钝化,钝化改善薄膜及器件的光电性能。瞬态和稳态光致发光荧光光谱表征结果说明钝化后的钙钛矿薄膜非辐射复合被抑制。这均有利于抑制载流子复合和提升开路电压。钝化后薄膜疏水性增强,更好地阻挡水汽侵蚀,提升稳定性。光强依赖性测试结果表明2-MP有效地钝化缺陷。J-V测试表明钝化后器件光电性能明显改善,开路电压最高达1.133 V,效率最高达21.66%。并且优化器件的稳定性显著改善,在氮气中储存97 d后效率保持初始效率的90%。 相似文献
39.
An acid-activated clay (Çanakkale montmorillonite from Turkey) was used to adsorb chlorophyll from hexane solutions. The phenomenon seems to be mainly driven by the interaction of chlorophyll with acid sites. The adsorption of chlorophyll on Brönsted acid sites was indicated by a characteristic infrared band for the -OH group at 3671 cm?1. The variations in the structure of clay mineral and chlorophyll during adsorption have been examined by differential thermal analysis, thermogravimetry and infrared spectroscopy of the activated clay before and after adsorption of chlorophyll. Oxidation of adsorbed chlorophyll was completed at quite a high temperature. 相似文献
40.
Yuhua Wang Eun-Koung An So-Jung Kim SangGuan You Jun-O Jin 《International journal of molecular sciences》2021,22(19)
Natural polysaccharides have shown promising effects on the regulation of immunity in animals. In this study, we examined the immune stimulatory effect of intranasally administered Codium fragile polysaccharides (CFPs) in mice. Intranasal administration of CFPs in C57BL/6 mice induced the upregulation of surface activation marker expression in macrophages and dendritic cells (DCs) in the mediastinal lymph node (mLN) and the production of interleukin-6 (IL-6), IL-12p70, and tumor necrosis factor-α in bronchoalveolar lavage fluid. Moreover, the number of conventional DCs (cDCs) was increased in the mLNs by the upregulation of C-C motif chemokine receptor 7 expression, and subsets of cDCs were also activated following the intranasal administration of CFP. In addition, the intranasal administration of CFPs promoted the activation of natural killer (NK) and T cells in the mLNs, which produce pro-inflammatory cytokines and cytotoxic mediators. Finally, daily administration of CFPs inhibited the infiltration of Lewis lung carcinoma cells into the lungs, and the preventive effect of CFPs on tumor growth required NK and CD8 T cells. Furthermore, CFPs combined with anti-programmed cell death-ligand 1 (PD-L1) antibody (Ab) improved the therapeutic effect of anti-PD-L1 Ab against lung cancer. Therefore, these data demonstrated that the intranasal administration of CFP induced mucosal immunity against lung cancer. 相似文献