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Chinese Chemical Letters 2009年第6期20卷 716-719页

作者： Long Zhang Xing Xin Cao hai xia jiang Biao jiang Yu Xin Cui State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Beijing 100191 China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

To investigate the structural form of gossypol and gossypolone Schiff＇s bases, seven relevant Schiff＇s bases were synthesized and the electrospray ionization-tandem mass spectrometry （ESI-MS/MS） with low-energy collision-induced dissociation was used to analyze their fragmentations. A common fragmentation pathway with the loss of RNH2 from those schiff＇s bases quasi-molecular ions was observed and proposed on the basis of their MS/MS spectra data. This common pathway indicated that those Schiff＇s bases existed mainly as the enamine form not the imine form previously showed in most reports.

关键词： Gossypol Schiff's bases Gossypolone Schiff's bases ESI-MS Enamine form Imine form

Electrochemical property of LiFePO4/C composite cathode with different carbon sources

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Rare Metals 2018年第9期37卷 743-749页

作者： Xin Li Yu Zhi jiang Xi Kun Li hai xia jiang Jun Long Liu Jun Feng Shi Bin Lin Xin Guan Shenyang Ligong University Shenyang 110159 China

To improve the performance of battery cathode materials that consist of carbonaceous organic material, carbon coatings on lithium iron phosphate （LiFePO4/C） materials were synthesized by different carbon sources. LiFePO4/C was synthesized by a combination method of sol-gel and gas-phase diffused permeation. LiFeO4/C materials were prepared by coating different carbon con- tents. High-performance composite materials were pre- pared by combining carbon with element doped by two modified methods. The elements of Fe and C came from Fe3＋ and sucrose, glucose, citric acid. Thermogravimetry- differential thermal analysis （TG-DTA）, X-ray diffrac- tometer （XRD）, scanning electron microscope （SEM）, cycle voltammetry （CV）, and charge-discharge test were used to characterize and test the surface morphology, structure, and electrochemical performance. The results show that LiFePO4/C synthesized with sucrose has higher specific discharge capacity than the other materials. The specific discharge capacity of this material is 84.27 mAh.g-1. The capacity retention could attain 94 % of the initial discharge capacity after 30 cycles, showing good electrochemical performance.

关键词： Solgel Gas-phase diffused permeation LiFePO4/C Sucrose Citric acid

Spatial snowdrift game in heterogeneous agent systems with co-evolutionary strategies and updating rules

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Chinese Physics B 2015年第4期24卷 22-35页

作者：夏海江李萍萍柯见洪林振权 College of Physics and Electronic Information Engineering Wenzhou University

We propose an evolutionary snowdrift game model for heterogeneous systems with two types of agents, in which the inner-directed agents adopt the memory-based updating rule while the copycat-like ones take the unconditional imitation rule; moreover, each＇agent can change his type to adopt another updating rule once the number he sequentially loses the game at is beyond his upper limit of tolerance. The cooperative behaviors of such heterogeneous systems are then investigated by Monte Carlo simulations. The numerical results show the equilibrium cooperation frequency and composition as functions of the cost-to-benefit ratio r are both of plateau structures with discontinuous steplike jumps, and the number of plateaux varies non-monotonically with the upper limit of tolerance VT as well as the initial composition of agents faO. Besides, the quantities of the cooperation frequency and composition are dependent crucially on the system parameters including VT, faO, and r. One intriguing observation is that when the upper limit of tolerance is small, the cooperation frequency will be abnormally enhanced with the increase of the cost-to-benefit ratio in the range of 0 〈 r 〈 1/4. We then probe into the relative cooperation frequencies of either type of agents, which are also of plateau structures dependent on the system parameters. Our results may be helpful to understand the cooperative behaviors of heterogenous agent systems.

关键词： cooperative behavior evolutionary snowdrift game heterogeneous agent system

Potential dependence in electrocatalysis:a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming xia Zeyu Wang Yinjuan Chen hai xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-ICR MS analysis

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Journal of Environmental Sciences 2025年第1期147卷 462-473页

作者： Kun Wang Haoyu Ren Shengwu Yuan xia jiang Pengfei Wang College of Water Sciences Beijing Normal UniversityBeijing 100875China National Engineering Laboratory of Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China

Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication *** organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake *** this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional *** findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and ***-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of *** properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel *** connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and *** results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.

关键词： Dissolved organic matter Fluorescence property Molecular composition Source

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： xia jiang Yanyan FANG xianlin ZENG Jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Distributions and risk assessment of heavy metals in solid waste in lead-zinc mining areas and across the soil, water body, sediment and agricultural product ecosystem in their surrounding areas

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China Geology 2025年第1期8卷 92-106页

作者： Zhi-qiang Wu hai-ying Li Liu-yan Lü Guo-jun Liang Ting-ting Wu jiang-xia Zhu No.117 Geological Team Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang 550023China Ecological Environment Monitoring Center of Guizhou Province Guiyang 550023China Guizhou Institute of Geological Survey Guiyang 550081China Environmental Engineering Assessment Center of Anshun City Anshun 561000China Environmental Emergency Center of Anshun City Anshun 561000China

To identify the root causes of heavy metal contamination in soils as well as prevent and control such contamination from its sources,this study explored the accumulation patterns and ecological risks of heavy metals like Cd and Pb in solid waste in mining areas and across the water body,sediment,soil and agricultural product ecosystem surrounding the mining *** on the residual solid waste samples in lead-zinc deposits in a certain area of Guizhou Province,along with samples of topsoils,irrigation water,river sediments,and crops from surrounding *** study analyzed the distributions of eight heavy metals,i.e.,Cd,As,Cr,Hg,Pb,Zn,Cu,and Ni,in the samples through field surveys and sample ***,this study assessed the contamination levels and ecological risks of heavy metals in soils,sediments,and agricultural products using methods such as the single-factor index,Nemerow composite index,and potential ecological risk *** results indicate that heavy metals in the solid waste samples all exhibited concentrations exceeding their risk screening values,with 60%greater than their risk intervention *** soils and sediments demonstrate slight and moderate comprehensive ecological risks of heavy *** single-factor potential ecological risks of heavy metals in both the soil and sediment samples decreased in the order of Hg,Cd,Pb,As,Cu,Zn,Cr,and Ni,suggesting the same sources of heavy metals in the soils and *** of the agricultural product samples exhibited over-limit concentrations of heavy metals dominated by Cd,Pb,Ni,and Cr,excluding Hg and *** agricultural product assessment using the Nemerow composite index reveals that 35%of the agricultural product samples reached the heavy metal contamination level,implying that the agricultural products from farmland around the solid waste dumps have been contaminated with heavy *** eight heavy metals in the soil,sediment,and agricultural product samples manifested hig

关键词： Lead-zinc mining area Solid waste Soil Water body Sediment Agricultural product Nemerow composite index Cd,Pb,Ni,Cr elements Heavy metal contamination Ecological risk assessment Coefficients of variation(CVs) Environmental restoration engineering

Do Institutional Investor Cliques Undermine Stock Price Efficiency?

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China & World Economy 2025年第1期33卷 223-258页

作者： hai jiang Shuangyi Chen Zifeng Wang School of Economics Jinan UniversityChina Dongguan Academy of Social Sciences China

This study investigates the effects of institutional investor cliques on stock price efficiency. Using a community network algorithm, it identifies cliques of institutional investors and finds that they significantly undermined stock price efficiency in China. The robustness of this finding is demonstrated through a range of methodologies, including the substitution of dependent variables, the alteration of estimation methods, the exclusion of data from extreme market periods, and the application of instrumental variables. The role of institutional investor cliques in diminishing market efficiency is attributed to market speculation. The detrimental effect of cliques on efficiency is exacerbated in environments characterized by low stock liquidity, poor information disclosure, and heightened panic among retail investors. However, regulatory interventions, such as inquiry letters, are shown to mitigate these effects and enhance market efficiency. These findings highlight the unexpected ways institutional investor cliques can influence emerging market economies and underscore the critical importance of effective regulation to safeguard market efficiency.

关键词： emerging market economics institutional investor clique stock pric efficiency

Influence of minor cerium addition on microstructure and fluidity of as-cast Al-Cu-Mn-Mg alloy

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Journal of Rare Earths 2025年第2期43卷 377-383页

作者： Yishan Wang Yu Bai Kaixi jiang Wenxue Fan Puxuan Wang hai Hao Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Ningbo Research Institute of Dalian University of Technology

Al-Cu-Mn alloys are widely used to produce automobile components like cylinder heads and engine blocks because of their capability to retain excellent thermal and mechanical characteristics at high ***,the Al-Cu-Mn-based alloys demonstrate restricted fluidity,leading to casting defects such as shrinkage and incomplete *** research investigated the microstructure and fluidity of Al-4.7Cu-1.0Mn-0.5Mg（wt%） alloy with minor cerium（Ce） *** as-cast alloys predominantly comprise α-Al matrix,accompanied by the presence of Al2Cu,Al6Mn,and Al8Cu4Ce *** influence of adding Ce on the fluidity of the Al-4.7Cu-1.0Mn-0.5Mg alloy was investigated using a trispiral fluidity test mold in this *** findings suggest that the addition of Ce within the range of 0.1 wt% to 0.5 wt% in the Al-4.7Cu-1.0Mn-0.5Mg alloy results in an enhancement in ***,the alloy containing 0.4 wt% Ce exhibits a significant increase in fluidity distance,from 349.7 to 485.7 *** improvement can be attributed to the reduction in viscosity,the refinement of secondary dendrite arm spacing,and the modification of secondary phase ***,a higher concentration of Ce leads to a decrease in fluidity length,potentially due to the formation of Al8Cu4Ce.

关键词： Al-Cu-Mn-Mg alloy Ce addition Fluidity Microstructure Rare earths

Comparisons of{100}texture improvement and formability in hot-rolled non-oriented electrical steel by austenite-ferrite phase transformation and shear deformation

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Journal of Iron and Steel Research International 2025年第1期32卷 171-185页

作者： Chi-hao Yu Hong-jiang Pan Yan-ping Zhao De-ting Tang hai-jun Wang Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093YunnanChina School of Electronics and Information Engineering Anshun UniversityAnshun561000GuizhouChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina

Over the years,the high magnetic induction of industrial Mn-added electrical steel is assumed to be the enhancement of{100}texture derived from its austenite-ferrite phase transformation during hot rolling(phase transformation(PT)method).However,it is still undetermined without straightforward experimental *** reason for{100}texture improvement of Mn-added electrical steel is experimentally confirmed due to the recrystallization induced by the austenite-ferrite phase transformation during hot ***,a more promising methodology to further improve{100}texture and formability of hot-rolled electrical steel is promoted by the control of hot rolling deformation condition(shear deformation(SD)method).The results show that the nucleation mechanisms of{100}oriented recrystallized grains are different in the samples by SD and PT methods,which are in-depth shear deformation and austenite-ferrite phase transformation,*** this case,coarse{100}oriented recrystallized grains and low residual stress are obtained in the sample by SD method,which is responsible for its superior{100}texture and *** contrast,the sample by PT method forms fine recrystallized grains with random orientations and accumulates severe residual stress.

关键词： Non-oriented electrical steel {100}texture Formability Austenite-ferrite phase transformation Shear deformation