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Chinese Chemical Letters 2000年第8期11卷 705-706页

作者： fan, cq Zhao, WM Qin, GW Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

A new bibenzyl 1 and a new phenanthrenedione 2 were identified from the stems of Dendrobium densiflorum (Orchidaceae).

关键词： Dendrobium densiflorum Orchidaceae phenanthrenedione bibenzyl

Co@C-N as an electronic mediator anchored with Cu2O nanoparticles enables efficient photoreduction of CO2 to CO with nearly 100% selectivity

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Science China Chemistry 2025年

作者： Xingbin Pan Xiuzheng Deng Jingshan fan Jiangchuan Liu Changhai Liu Zhongyu Li Qian Liang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology CNPC-CZU Innovation Alliance School of Petrochemical Engineering Changzhou University School of Materials Science & Engineering Changzhou University

Solar-driven CO2conversion into value-added chemical provides an attractive strategy for sustainable development. However,the enhanced CO2photoreduction performance with target product selectivity remains a major challenge. Here, we develop a novel strategy involving Cu2O nanoparticles in situ grown on the surface of ZIF-67-derived Co@C-N nanocages （CC） to create abundant active sites and appropriate heterointerfaces. A remarkable CO selectivity of 95.7%with a yield of 117.39μmol g-1h-1and an apparent quantum efficiency as high as 1.88%at 420 nm was obtained over CC-60 catalyst in pure water, which was 87.6times higher than that of pure Cu2O. Theoretical calculations and experiments indicated that Co@C-N nanocages as charge mediator not only rapidly trap photogenerated electrons to promote charge separation efficiency, but also regulate the d-band center of Cu atoms to move to the Fermi energy level, thereby optimizing the reaction kinetics to facilitate the highly selective conversion of the key intermediate *CO desorption to CO.

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Fabrication of Multilayer Film Electrode Containing 12-Tungstosilicate Anions and Its Electrocatalytic Reduction for Dioxygen

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Chinese Chemical Letters 1997年第10期8卷 913-916页

作者： Sun, cq Zhang, JD JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA

A novel multilayer film electrode containing 12-tungstosilicate anions was achieved on the surface of gold electrode by alternating deposition of 12-tungstosilicate anions with 60% quaternized poly(4-vinylpyridine) based on electrostatic interaction. The chemically-modified electrode exhibits a high catalytic activity towards the electroreduction of molecular oxygen.

关键词： Fabrication of Multilayer Film Electrode Containing 12-Tungstosilicate Anions and Its Electrocatalytic Reduction for Dioxygen

Birkhoff lower-dimensional tori in Hamiltonian systems

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Chinese Science Bulletin 1997年第22期42卷 1866-1870页

作者： Wang, SL Cheng, cq Nanjing Univ Dept Math Nanjing 210093 Peoples R China

CONSIDER a Cl （l≥3） area-preserving diffeomorphism f: U→R2, defined in a neighbourhoodU of origin O in a plane and assume that f（O）=O and Df（O） has a pair of pure imaginaryeigenvalues e±iω0 ω0≠2πm/n, i. e. origin O is an elliptic fixed point of f. In generic casesone can write f=B+C, where the ristriction of B to each circle p2+q2=2τis a

关键词： Hamiltonian system resonance lower-dimensional torus.

Aging Effect on Elapsed Time of Serrations in Al-Li Single Crystals

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Journal of Materials Science & Technology 1998年第4期14卷 353-356页

作者： Tian, BH Yan, MG Chen, cq Beijing Inst Aeronaut Mat Beijing 100095 Peoples R China Beijing Univ Aeronaut & Astronaut Beijing 100083 Peoples R China

Elapsed time of serrations in AI-Li single crystals was investigated with two definitions: one is the time elapsed in one cycle of serrations, the other is the average elapsed time within a strain limit. Elapsed time of individual serration appears independent on stress drops during serrated flow. It primarily distributes within the limits of short elapsed time in peak aged condition compared with underaged and overaged conditions, corresponding to low level of the average elapsed time that appears indifferent to increasing strain. It seems that shearing behaviour of delta' particles could be responsible for the variations in elapsed time of serrations.

关键词： Aluminum alloys

Species distribution of polymeric aluminium ferrum——timed complexation colorimetric analysis method of Al-Fe-Ferron

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Journal of Environmental Sciences 2001年第4期13卷 418-421页

作者： Hu, YY Tu, cq Wu, HH S China Univ Technol Coll Paper & Environm Engn Guangzhou 510640 Peoples R China

The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexatian colorimetric analysis method of Al-Fe-ferron in view of the total concentration of {AI + Fe} was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 net and the testing pH value was 5. With a comparison of the ratios of n(Al)/n(Fe), the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were carious in both the molar n(Al)/n(Fe) ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total ( Al + Fe which ranged from 10(-5) to 10(-4) mol/L..

关键词： polymeric aluminum-ferrum species distribution timed complexation colarimetric analysis method Al-Fe-ferron

HERMITE-TYPE METHOD FOR VOLTERRA INTEGRAL EQUATION WITH CERTAIN WEAKLY SINGULAR KERNEL

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Journal of Computational Mathematics 1995年第4期13卷 306-314页

作者： Han, cq Zhang, IQ S CHINA UNIV TECHNOL DEPT COMP SCICANTONPEOPLES R CHINA S CHINA UNIV TECHNOL AUTOMAT DEPTCANTONPEOPLES R CHINA

We discuss the Hermite-type collocation method for the solution of Volterra integral equation with weakly singular kernel. The constructed approximation is a cubic spline in the continuity class C-1. We prove that thi... 详细信息

关键词： Math Ky

Algebraic constructions of asymptotically optimal two-dimensional optical orthogonal codes

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Chinese Science Bulletin 1997年第19期42卷 1659-1662页

作者： Xu, cq Yang, YX Department of Information Engineering Beijing University of Post and Telecommunication Beijing China

1 Preliminaries The mathematical definition of the two-dimensional optical orthogonal code(2-D OOC)is as follows: Definition 1. A(mn, ω,λ_a,λ_c) 2-DOOC consists of a set of(O, 1) m×n matri-

关键词： optical orthogonal codes CDMA optical communications coding.

Paleovalley in the Yannan-Sancang area of Jiangsu Province and its geological significance

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Chinese Science Bulletin 1997年第11期42卷 924-927页

作者： Li, CX Wan, MH Chen, cq Department of Marine Geology and Geophysics Tongji University Shanghai China

IN the southern Yellow Sea there exists a large radial sand ridge system,which covers about20 000 km^*** ridges and troughs occur alternately within the system,and single sandridges are tens of kilometers,even more than one hundred kilometers long and ten to fifteenkilometers *** to the distribution pattern of the radial sand ridge system being like

关键词： digital ground penetrating radar paleovalley radial sand ridge.

THE DIGESTION OF SYNTHETIC GIBBSITE

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中国有色金属学会会刊：英文版 1995年第3期5卷 45-49页

作者： Li, cq Zhang, PM Chen, QY Chen, XM HUNAN INST DIAMOND PROD CHANGSHA 410011PEOPLES R CHINA CENT S UNIV TECHNOL CHANGSHA 410083PEOPLES R CHINA

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关键词： synthetic gibbsite digestion heat effect kinetic behavior