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991.
Dr. Sheng Chu Dr. Shizhao Fan Dr. Yongjie Wang Dr. David Rossouw Yichen Wang Prof. Gianluigi A. Botton Prof. Zetian Mi 《Angewandte Chemie (International ed. in English)》2016,55(46):14262-14266
Syngas, the mixture of CO and H2, is a key feedstock to produce methanol and liquid fuels in industry, yet limited success has been made to develop clean syngas production using renewable solar energy. We demonstrated that syngas with a benchmark turnover number of 1330 and a desirable CO/H2 ratio of 1:2 could be attained from photoelectrochemical CO2 and H2O reduction in an aqueous medium by exploiting the synergistic co‐catalytic effect between Cu and ZnO. The CO/H2 ratio in the syngas products was tuned in a large range between 2:1 and 1:4 with a total unity Faradaic efficiency. Moreover, a high Faradaic efficiency of 70 % for CO was acheived at underpotential of 180 mV, which is the lowest potential ever reported in an aqueous photoelectrochemical cell. It was found that the combination of Cu and ZnO offered complementary chemical properties that lead to special reaction channels not seen in Cu, or ZnO alone. 相似文献
992.
Juan Xue Yingying Mi Zhibin Wang Yichun Sun Qiong Wu Changfu Wang Hongwei Zhang Xin Yang Haixue Kuang Qiuhong Wang 《Journal of separation science》2016,39(10):1825-1833
A selective and sensitive ultra‐high performance liquid chromatography with tandem mass spectrometry method was developed and validated for the determination and pharmacokinetic study of (+)‐8‐hydroxypinoresinol‐4’‐O‐β ‐D‐glucopyranoside, prinsepiol‐4‐O‐β‐D‐glucopyranoside, (+)‐pinoresinol‐4,4’‐di‐O‐β‐D‐glucopyranoside, and (−)‐massoniresinol 3α‐O‐β‐D‐glucopyranoside in rat plasma after the oral administration of a Valeriana amurensis extract. The analytes and ethyl 4‐hydroxybenzoate (internal standard) were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column. The detection was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode using an electrospray ionization source operating in negative ionization mode. The linear ranges (ng/mL) of the standard curves were 0.39–154.00, 0.62–244.70, 0.50–198.60, and 0.34–134.50 for (+)‐8‐hydroxypinoresinol‐4’‐O‐β‐D‐glucopyranoside, prinsepiol‐4‐O‐β‐D‐glucopyranoside, (+)‐pinoresinol‐4,4’‐di‐O‐β‐D‐glucopyranoside, and (−)‐massoniresinol 3α‐O‐β‐D‐glucopyranoside, respectively. The inter‐ and intra‐day precisions were less than 11.0%, the accuracies were between −5.9 and 7.7%, and the extraction recoveries of the four analytes were > 81.2% from rat plasma. The method was successfully applied to a pharmacokinetic study of the four analytes after oral administration of a Valeriana amurensis extract to rats. The developed method has the potential for pharmacokinetic analysis and to provide additional information in the clinical application of Valeriana amurensis. 相似文献
993.
V. N. Ryadovikov A. N. Aleev E. N. Ardashev A. G. Afonin V. P. Balandin S. G. Basiladze S. F. Berezhnev G. A. Bogdanova M. Yu. Bogolyubsky A. M. Vischnevskaya V. Yu. Volkov A. P. Vorobiev A. G. Voronin V. F. Golovkin S. N. Golovnia S. A. Gorokhov N. I. Grishin Ya. V. Grishkevich G. G. Ermakov P. F. Ermolov I. N. Erofeeva V. N. Zapolsky E. G. Zverev D. E. Karmanov V. I. Kireev A. A. Kiriakov V. N. Kramarenko A. V. Kubarovsky N. A. Kouzmine L. L. Kurchaninov G. I. Lanshikov A. K. Leflat M. M. Merkin G. Ya. Mitrofanov V. S. Petrov Yu. P. Petukhov A. V. Pleskach V. V. Popov V. M. Ronjin V. N. Ryadovikov V. A. Senko M. M. Soldatov L. L. Tikhonova N. F. Furmanec A. G. Kholodenko Yu. P. Tsyupa N. A. Shalanda A. I. Yukaev V. I. Yakimchuk 《Physics of Atomic Nuclei》2016,79(2):144-154
The results of an analysis of data from the SERP-Е-184 experiment devoted to studying mechanisms of the production of charmed particles in proton–nucleus interactions at 70 GeV and their decays are presented. The data in question were obtained upon irradiating the SVD-2 active target consisting of carbon, silicon, and lead plates with a beam of 70-GeV protons. A detailed simulation on the basis of the FRITIOF7.02 and GEANT3.21 code packages made it possible to optimize event-selection criteria and to calculate the detection efficiency for Λc+ baryons. After selecting a signal from the threebody decay of a Λc+ baryon, the inclusive cross section for its production at near-threshold energies, its lifetime, and the parameter of the A dependence of the cross section were found. The Λc+ -baryon yields are tabulated along with data from other experiments and theoretical predictions. 相似文献
994.
W. Sprößig In this paper, we propose a new adaptive method for frequency‐domain identification problem of discrete LTI systems. It is based on a dictionary that is consisting of normalized reproducing kernels. We prove that the singular values of the matrix generated by this dictionary converge to zero rapidly; this makes it quite efficient in representing the original systems with only a few elements. For different systems, it results in different selected sequences from the dictionary, that is, its adaptivity. Meanwhile, the stability of results is automatically guaranteed according to the structure of the dictionary. Two examples are presented to illustrate the idea. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
995.
A double-helical octanuclear Cu(II) wheel 1 with 2.88 nm diameter was prepared through the reaction of a clinical medicine, telmisartan, with copper sulfate. Central copper ions can be partially replaced by bivalent zinc and cobalt ions and fully exchanged by trivalent iron ions. The properties of central metal ion-exchanged variants are much different from those of 1. Central metal ion exchange might be regarded as a powerful and effective method to modify properties from one crystalline material to another only by varying central metal ions under moderate conditions. 相似文献
996.
Shucong Zhang Dr. Chunhui Tan Ruipeng Yan Xifei Zou Prof. Fei-Long Hu Prof. Yan Mi Dr. Cheng Yan Dr. Shenlong Zhao 《Angewandte Chemie (International ed. in English)》2023,62(26):e202302795
Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built-in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide-cobalt nanowire arrays grown on carbon fiber paper (Ni2P-CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni2P-CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm−2, respectively. Moreover, the assembled lab-scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface-induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high-performance heterogeneous electrocatalysts. 相似文献
997.
Prof. Xingwei Li Heng Song Prof. Songjie Yu Dr. Ruijie Mi Dr. Xiao-Xi Li 《Angewandte Chemie (International ed. in English)》2023,62(37):e202305669
The incorporation of fluorine atoms in organics improves their bioactivity and lipophilicity. Catalytic functionalization of gem-difluorodienes represents one of the most straightforward approaches to access fluorinated alkenes. In contrast to the regular 1,3-dienes that undergo diverse asymmetric di/hydrofunctionalizations, the regio- and enantioselective oxyamination of gem-difluorodienes remains untouched. Herein, we report asymmetric 1,4-oxyamination of gem-difluorodiene by chiral rhodium-catalyzed three-component coupling with readily available carboxylic acid and dioxazolone, affording gem-difluorinated 1,4-amino alcohol derivatives. Our asymmetric protocol exhibits high 1,4-regio- and enantioselectivity with utility in the late-stage modification of pharmaceuticals and natural products. Stoichiometric experiments provide evidences for the π-allylrhodium pathway. Related oxyamination was also realized when trifluoroethanol was used as an oxygen nucleophile. 相似文献
998.
Jia-Jia Lang Dr. Pengbing Mi Dr. Xiao-Juan Wang Shu-Qin Gao Prof. Dr. Xiangshi Tan Prof. Dr. Ying-Wu Lin 《欧洲无机化学杂志》2023,26(9):e202200727
Two readily-accessible molybdenum complexes with low sterically hindered S, N-bidentate ligands were designed for the reduction of nitrate to nitrite. The Lewis acid Sc(III) acted as a significant co-catalyst to enhance the catalytic efficiency by activating the N−O bond of nitrate. This study indicates that molybdenum complexes in cooperation with a Lewis acid offer functional Mo-catalyst systems, which present functional artificial models of the natural molybdenum enzymes. 相似文献
999.
Han AR Jin Jeong Y Kang Y Lee JY Sook Seo M Nam W 《Chemical communications (Cambridge, England)》2008,(9):1076-1078
A high-valent iron(IV)-oxo porphyrin pi-cation radical is an active oxidant in the catalytic oxygenation of organic substrates by an iron(III) porphyrin complex and peracids, whereas an iron(III)-oxidant porphyrin adduct is a sluggish oxidant in iron porphyrin model reactions. 相似文献
1000.
A facile combinatorial strategy was developed for the construction of libraries of functionalized chiral ionic liquids (FCILs) including doubly chiral ionic liquids and bis-functional chiral ionic liquids. These FCIL libraries have the potential to be used as asymmetric catalysts or chiral ligands. As an example, novel asymmetric bifunctional catalysts were developed by simultaneously incorporating functional groups onto the cation and anion. The resultant bis-functionalized CILs showed significantly improved stereoselectivity over the mono-functionalized parent CILs. 相似文献