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Visible-light photoredox-mediated oxidation of N-methyl tertiaryamines under catalyst free conditions:Direct synthesis of methylene-bridged bis-1,3-dicarbonyl compounds

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Chinese Chemical Letters 2014年第4期25卷 545-548页

作者： xiao-Jun Dai xiao-liang Xu Dong-Ping Cheng xiao-Nian Li Institute of Industrial Catalysis College of Chemical Engineering and Materials ScienceZhejiang University of Technology College of Pharmaceutical Science Zhejiang University of Technology

Mediated by visible light-induced photoredox catalysis and free of other catalysts, a new and efficient synthesis of methylene-bridged bis-l,3-dicarbonyl derivatives has been developed. A variety of N-methyl tertiarya... 详细信息

关键词： Photochemistry Oxidation Aliphatic tertiaryamine Catalyst free

A Monotonic Algorithm for Eigenvalue Optimization in Shape Design Problems of Multi-Density Inhomogeneous Materials

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Communications in Computational Physics 2010年第8期8卷 565-584页

作者： Zheng-fang Zhang Ke-wei liang xiao-liang Cheng Department of Mathematics Zhejiang UniversityHangzhou 310027China

Many problems in engineering shape design involve eigenvalue *** relevant difficulty is that the eigenvalues are not continuously differentiable with respect to the *** this paper,we are interested in the case of multi-density inhomogeneous materials which minimizes the least *** the finite element discretization,we propose a monotonically decreasing algorithm to solve the minimization *** numerical examples are provided to illustrate the efficiency of the present algorithm as well as to demonstrate its availability for the case of more than two *** the computations are sensitive to the choice of the discretization mesh sizes,we adopt the refined mesh strategy,whose mesh grids are 25-times of the amount used in[*** and ***,***.,171(2001),pp.272-288].We also show the significant reduction in computational cost with the fast convergence of this algorithm.

关键词： Multi-density inhomogeneous materials the least eigenvalue optimization problem finite element method monotonic algorithm

Optimal LQG control for discrete time-varying system with multiplicative noise and multiple state delays

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Control Theory and Technology 2021年第3期19卷 328-338页

作者： xiao Lu Qiyan Zhang xiao liang Haixia Wang Chunyang Sheng Zhiguo Zhang Shandong University of Science and Technology QingdaoChina

This paper is concerned with the optimal linear quadratic Gaussian(LQG)control problem for discrete time-varying system with multiplicative noise and multiple state *** main contributions are ***,in virtue of Pontryagin’s maximum principle,we solve the forward and backward stochastic difference equations(FBSDEs)and show the relationship between the state and the ***,based on the solution to the FBSDEs and the coupled difference Riccati equations,the necessary and sufficient condition for the optimal problem is ***,an explicit analytical expression is given for the optimal LQG *** examples are shown to illustrate the effectiveness of the proposed algorithm.

关键词： LQG control Discrete time-varying system Multiplicative noise Multiple state delays

Hybrid architecture design enhances the areal capacity and cycling life of low-overpotential nanoarray oxygen electrode for lithium–oxygen batteries

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Journal of Energy Chemistry 2020年第7期29卷 248-255,I0008页

作者： liang xiao Duo Wang Ming Li Bohua Deng Jinping Liu School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070HubeiChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

Transition metal oxide(TMO)nanoarrays are promising architecture designs for self-supporting oxygen electrodes to achieve high catalytic activities in lithium-oxygen(Li-O2)***,the poor conductive nature of TMOs and the confined growth of nanostructures on the limited surfaces of electrode substrates result in the low areal capacities of TMO nanoarray electrodes,which seriously deteriorates the intrinsically high energy densities of Li-O2 ***,we propose a hybrid nanoarray architecture design that integrates the high electronic conductivity of carbon nanoflakes(CNFs)and the high catalytic activity of Co3 O4 nanosheets on carbon cloth(CC).Due to the synergistic effect of two differently featured components,the hybrid nanoarrays(Co3 O4-CNF@CC)achieve a high reversible capacity of3.14 mA h cm-2 that cannot be achieved by only single ***,CNFs grown on CC induce the three-dimensionally distributed growth of ultrafine Co3 O4 nanosheets to enable the efficient utilization of ***,with the high catalytic efficiency,hybrid Co3 O4-CNF@CC also achieves a more prolonged cycling life than pristine TMO *** present work provides a new strategy for improving the performance of nanoarray oxygen electrodes via the hybrid architecture design that integrates the intrinsic properties of each component and induces the three-dimensional distribution of catalysts.

关键词： Hybrid architecture Nanoarray oxygen electrode Synergistic effect Three-dimensional current collector Lithium-oxygen batteries

A review of gold extraction using noncyanide lixiviants: Fundamentals, advancements, and challenges toward alkaline sulfur-containing leaching agents

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 417-431页

作者： Chun-bao Sun xiao-liang Zhang Jue Kou Yi Xing School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Alkaline sulfur-containing lixiviants,including thiosulfate,polysulfides,and alkaline sulfide solutions,stand out as a promising class of alternatives to cyanide because of their low toxicity,high efficiency,and strong *** this paper,we summarized the research progress and remaining challenges in gold extraction using these noncyanide *** a brief introduction to the preparation method,the transformation process of various sulfur-containing species in alkaline solutions was ***,some insights into the mechanism of gold leaching in alkaline sulfur-containing solutions were presented from different aspects,including thermodynamics analysis,electrochemical dissolution,and leaching ***,recent progress in in-situ generation of sulfur-containing anions from gold-bearing sulfide minerals was outlined as *** passivation caused by sulfur species was discussed in particular because it is considered the greatest challenge facing sulfur-containing leaching *** sulfur-containing lixiviants are expected to serve as alternatives in industrial applications of gold extraction,particularly for refractory gold ores containing copper and carbonaceous matter.

关键词： gold extraction sulfur-containing lixiviants degradation in-situ generation passivation

Immobilization of urease in metal–organic frameworks via biomimetic mineralization and its application in urea degradation

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Chinese Journal of Chemical Engineering 2020年第8期28卷 2173-2180页

作者： xiao liang Qing Li Zhiyuan Shi Shaowei Bai Quanshun Li Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education School of Life SciencesJilin UniversityChangchun 130012China

Enzyme immobilization has been accepted as an efficient technique for improving the stability and recyclability of ***,biomimetic mineralization strategy was employed to achieve the immobilization of urease in a type of metal–organic frameworks(zeolite imidazolate framework-8,ZIF-8),and the immobilized enzyme urease@ZIF-8 was systematically evaluated for its structure,activity,stability and recyclability,using the hydrolysis of urea as a *** entrapment of urease was found to be realized in a synchronous manner with the formation of ZIF-8 *** loading of urease in ZIF-8 was measured to be ca.10.6%through the bicinchoninic acid(BCA)protein *** encapsulated urease could efficiently maintain its native conformation,which endowed the immobilized urease with excellent activity and stability,even in harsh conditions(e.g.,in the presence of trypsin,acidic or alkali conditions,or at high temperature).Further,urease@ZIF-8 exhibited good recyclability during the degradation of urea,in which it could keep 58.86%of initial activity after being used for 5 ***,biomimetic mineralization could be potentially utilized as a promising method to prepare immobilized ureases with superior activity,stability and recyclability,thereby facilitating the construction of efficient catalysts for industrial biocatalysis and biosensing.

关键词： Urease Metal–organic frameworks Immobilization Biomimetic mineralization Stability Recyclability

Adaptive minimum bit feedback for sum-rate analysis in multi-user distributed antenna systems

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 32-36页

作者： ZHANG xiao-liang JI Hong LI Xi Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

The paper mainly studies the sum-rate performance of limited feedback （LFB） block-diagonalization （BD） in multi-user distributed antenna system （DAS）. As the channel state information （CSI） fed back to base station （BS） is limited, multi-user interference （MUI） is caused inevitably because of the quantization error. Considering the influence of the MUI to the capacity of DAS, we propose a parameter of effective sum-rate ratio （ESRR） to denote the capacity offset under the condition of the BS can get perfect CSI and limited CSI first, then we confirm that the approximated ESRR is very close to actual ESRR got through simulations. After that, based on the approximated ESRR, an adaptive minimum bit feedback scheme which can effectively reduce the overhead of feedback channel and the complexity of the system is proposed. Simulation results show the effectiveness of the proposed scheme.

关键词： BD DAS ESRR minimum bit feedback

Synthesis of azobenzene-containing liquid crystalline gelator for use in liquid crystal gels

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Chinese Chemical Letters 2008年第5期19卷 521-524页

作者： Guang Wang xiao liang Zhao Yue Zhao Faculty of Chemistry Northeast Normal University Changchun 130024 China Department of Chemistry University of Sherbrooke Sherbrooke Canada JIK 2

A liquid crystalline gelator containing the azobenzene chromophore was synthesized for the first time; it was used to form self- assembled network in nematic liquid crystals resulting in liquid crystal gels with disti... 详细信息

关键词： Gelator Azobenzene Synthesis Liquid crystal

On the optimal harvesting of size-structured population dynamics

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Applied Mathematics(A Journal of Chinese Universities) 2013年第2期28卷 173-186页

作者： LIU Yan CHENG xiao-liang HE Ze-rong Department of mathematics Zhejiang University Institute of Operational Research and Cybernetics Hangzhou Dianzi University

This work is concerned with a kind of optimal control problem for a size-structured biological population ***-posedness of the state system and an adjoint system are proved by means of Banach＇s fixed point *** and uniqueness of optimal control are shown by functional analytical *** conditions describing the optimal strategy are established via tangent and normal cones *** results are of the first ones for this novel structure.

关键词： Body size population model optimal harvest maximum principle normal cone.