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The importance of selective oxidation for the progress of green/sustainable chemistry is pointed out and the state of the art of heterogeneous selective oxidation of alkanes described, taking for examples the selective oxidations to form oxygenated products (1) of isobutane catalyzed by heteropoly-based mixed oxides and (2) of n-butane to maleic anhydride catalyzed by vanadium phosphorous mixed oxides. In addition, efforts necessary to bring about breakthroughs in this field are discussed. 相似文献
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J.W. Lyding T.-C. Shen G.C. Abeln C. Wang P.A. Scott J.R. Tucker PH. Avouris R.E. Walkup 《Israel journal of chemistry》1996,36(1):3-10
Nanofabrication on silicon surfaces has been achieved in a manner similar to e-beam/resist technology, in which hydrogen serves as a monolayer resist for exposure by the electron beam from an ultrahigh vacuum (UHV) scanning tunneling microscope (STM). In this scheme, hydrogen is selectively desorbed from Si(100)2×1:H surfaces that have been prepared by atomic hydrogen dosing under UHV background conditions. To remove hydrogen, the tip bias is raised, under feedback control, and then the desired pattern is drawn. Two regimes of hydrogen desorption are observed: at higher energies, above ∼6.0 V, direct electron-stimulated desorption occurs, whereas at lower biases, desorption occurs via a multiple excitation vibrational heating mechanism and exhibits a strong current dependence. Patterning linewidth down to a single dimer row has been achieved in the vibrational heating regime. The selective removal of hydrogen suggests many possibilities for subsequent chemical treatments in which the hydrogen-terminated silicon remains inert. We have performed experiments which demonstrate selective oxidation of, and nitrogen incorporation into, the STM-patterned regions. 相似文献
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F. Zaccheria N. Ravasio A. Fusi M. Rodondi R. Psaro 《Advanced Synthesis \u0026amp; Catalysis》2005,347(9):1267-1272
The selectivity of Cu/Al2O3 under very mild catalytic hydrogenation conditions can be tuned only by switching the solvent. Geraniol can be converted in a one‐pot one‐step process into a mixture of citronellol and menthol in hydrocarbon solvents or reduced to citronellol with 98% selectivity in 2‐propanol without any additive. Both reactions can be applied to essential oils or synthetic mixtures containing geraniol, citronellal and nerol. 相似文献
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Elodie G. Rodrigues Sónia A. C. Carabineiro Xiaowei Chen Juan J. Delgado José L. Figueiredo Manuel F. R. Pereira José J. M. Órfão 《Catalysis Letters》2011,141(3):420-431
Abstract
Noble metal catalysts (Pt, Ir, Pd, Rh, Au) supported on activated carbon were assessed for glycerol oxidation. Rhodium is a highly efficient catalyst when the support has neutral or basic properties. The surface chemistry of activated carbon plays a key role in the performance. 相似文献5.
W. Peter Lippert Christian Burschka Dr. Kathrin Götz Martin Kaupp Prof. Dr. Diana Ivanova Claudine Gaudon Dr. Yoshiteru Sato Dr. Pierre Antony Dr. Natacha Rochel Dr. Dino Moras Dr. Hinrich Gronemeyer Dr. Reinhold Tacke Prof. Dr. 《ChemMedChem》2009,4(7):1143-1152
C/Si switch : Twofold sila‐substitution (C/Si exchange) in the RXR‐selective retinoids 4 a (SR11237) and 5 a leads to 4 b (disila‐SR11237) and 5 b , respectively. Chemistry and biology of the C/Si pairs are reported.
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化学工业中的新课题——绿色化学 总被引:4,自引:0,他引:4
绿色化学是从源头上防止污染的化学。通过现存环境治理的局限性和绿色化学在环境友好方面的巨大作用和潜力的介绍 ,导出绿色化学取代传统化学的必然性。 相似文献
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应化专业化学实验教学体系的构建 总被引:1,自引:0,他引:1
化学实验在培养学生"动手能力和创新精神"方面具有重要作用。我们化教学内容,我们构建了基础型、综合型与设计型三个层次的实验课程教学模式,并构建了创新性实验教学开放体系、化学实验多媒体教学体系、多元化实验考试评价体系。实践证明,新的实验教学体系更适应创新性人才培养的要求。 相似文献
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