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Nano Research 2023年第5期16卷 6552-6559页

作者： LiLi zhang Zongpeng Wang Jitang zhang Zhiping Lin qinghua zhang Wenwu Zhong Guangfeng Wu College of Material Science and Engineering Changchun University of TechnologyChangchun 130051China Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou UniversityJiaojiang 318000China Institution of Physics Chinese Academic of ScienceBeijing 100190China

The fabrication of heterointerface materials with hierarchical morphologies more than two levels is a challenging yet promising approach to achieve optimal electrocatalyst for hydrogen evolution reaction(HER).Here,using a facile two-step method,we are able to prepare the Ni_(2)P/(Co,Ni)OOH heterointerface with a three-level hierarchy *** multiple levels of hierarchy structures not only offer considerable area for active sites loading,but also facilitate the substance transportation,both beneficial for ***,the strong charge transfer at the Ni_(2)P/(Co,Ni)OOH heterointerface eliminates the spin asymmetry and achieves the thermos-neutral adsorption of active H ***,the resulted Coulomb attraction stacks the two materials firmly,facilitating the *** functional theory(DFT)and in-situ Raman measurements reveal the sufficient Ni atoms acting as the active *** these merits,the Ni_(2)P/(Co,Ni)OOH exhibits much better HER activity than the separate Ni_(2)P or(Co,Ni)OOH,affording a current density of 100 mA/cm^(2)at an overpotential of 169 mV and a Tafel slope of 41 mV/dec,when tested in alkaline *** work provides inspiration for optimizing the intrinsic HER activity utilizing multiple-level hierarchy structures.

关键词： hydrogen evolution reaction Ni_(2)P/(Co,Ni)OOH heterointerface hierarchy

A combined mixed finite element method and local discontinuous Galerkin method for miscible displacement problem in porous media

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Science China Mathematics 2014年第11期57卷 2301-2320页

作者： GUO Hui zhang qinghua YANG Yang College of Science China University of Petroleum Michigan Technological University

A combined method consisting of the mixed finite element method for flow and the local discontinuous Galerkin method for transport is introduced for the one-dimensional coupled system of incompressible miscible displacement problem. Optimal error estimates in L∞(0,T;L2) for concentration c,in L2(0,T;L2)for cxand L∞(0,T;L2) for velocity u are derived. The main technical difficulties in the analysis include the treatment of the inter-element jump terms which arise from the discontinuous nature of the numerical method,the nonlinearity,and the coupling of the models. Numerical experiments are performed to verify the theoretical results. Finally,we apply this method to the one-dimensional compressible miscible displacement problem and give the numerical experiments to confirm the efficiency of the scheme.

关键词： mixed finite element method local discontinuous Galerkin method error estimate miscible displacement problem

Attribute reduction based on fuzziness of approximation set in multi-granulation spaces

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The Journal of China Universities of Posts and Telecommunications 2016年第6期23卷 16-23页

作者： Xu Kai zhang qinghua Xue Yubin Hu Feng Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and Telecommunications School of Science Chongqing University of Posts and Telecommunications

Rough set theory is an important tool to solve uncertain problems. Attribute reduction, as one of the core issues of rough set theory, has been proven to be an effective method for knowledge acquisition. Most of heuristic attribute reduction algorithms usually keep the positive region of a target set unchanged and ignore boundary region information. So, how to acquire knowledge from the boundary region of a target set in a multi-granulation space is an interesting issue. In this paper, a new concept, fuzziness of an approximation set of rough set is put forward firstly. Then the change rules of fuzziness in changing granularity spaces are analyzed. Finally, a new algorithm for attribute reduction based on the fuzziness of 0.5-approximation set is presented. Several experimental results show that the attribute reduction by the proposed method has relative better classification characteristics compared with various classification algorithms.

关键词： rough set approximation set fuzziness attribute reduction multi-granulation

Aluminum impregnated silica catalyst for Friedel–Crafts reaction：Influence of ordering mesostructure

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1533-1538页

作者： Yibo He qinghua zhang Xiaoli Zhan Dangguo Cheng Fengqiu Chen College of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China

Friedel–Crafts alkylation of benzene with linear chain ole fin(C_(10)–C_(14)),which is an important reaction of synthetic detergent,was studied via different catalysts of aluminum impregnated silica molecular ***_3 was immobilized on silica molecular sieves with different channel structures,hexagonal packing channels network(SBA-15,MCM-41),and disordered channel network(SiO_2,SiO_2-Gel) by *** and N_2 adsorption–desorption isotherms con firmed that the speci fic mesoporous structures were maintained for order channel network catalyst after *** activities were investigated under different *** in fluences of channel structure were *** results showed that catalyst based on mesoporous like SBA-15 had the highest catalytic activities and 2-LAB selectivity compared with other catalysts in this *** highest 2-LAB selectivity was nearly 50% when 1-dodecene conversion was nearly 100%.At low 1-dodecene conversion or higher benzene/1-dodecene molar ratio,2-LAB selectivity was nearly 60%.

关键词： Friedel-Crafts Alkylation Aluminum Catalyst Molecular sieves

Monitoring and detection of steel bridge diseases:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 188-208页

作者： Chuang Cui qinghua zhang Dengke zhang Wulve Lao Lemou Wu Zhenxiong Jiang National Key Laboratory of Bridge Intelligent and Green Construction Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Jiangsu Provincial Transportation Engineering Construction Bureau Nanjing 210004China

Fatigue,corrosion,and bolt loosening are the main causes of structural performance degradation and collapse in steel *** monitoring of steel bridge diseases is a basic premise for ensuring high-quality operation and maintenance of steel *** this regard,a summary and analysis were conducted on the classification of steel bridge diseases,monitoring and detection methods,application statuses,and major *** main causes,research status,and development trends of steel bridge diseases are *** results showed that,for fatigue crack problems,fatigue crack initiation has a small scale,high difficulty in monitoring and detection,few methods,and low *** the cracks grow,the difficulty of monitoring and detection decreases,the number of methods increases,and the accuracy *** crack monitoring and detection are affected by the environmental and vehicular *** corrosion features are evident in steel bridges,and corrosion identification methods and technologies are rapidly *** and detecting corrosion in concealed areas is difficult and requires further improvements in monitoring and detection technologies and their *** and detection methods and supporting equipment for bolt loosening in steel bridges are rapidly *** development of intelligent monitoring and detection technologies and supporting equipment is an important research topic that urgently needs to be addressed for the full-lifecycle operation and maintenance of steel bridges and the sustainable development of bridge *** new intelligent sensing components based on high-performance materials and sensing element design theory to improve the monitoring and detection perception ability is an important development direction for steel bridge monitoring and *** on intelligent monitoring and detection technologies,standardized indicators,and related topics based on intelligent oper

关键词： Steel bridge Diseases Fatigue crack Corrosion Bolt loosening Monitoring and detection

Electrochemical conversion of CO2 to syngas with a wide range of CO/H2 ratio over Ni/Fe binary single-atom catalysts

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Nano Research 2020年第12期13卷 3206-3211页

作者： Meng zhang Zheng Hu Lin Gu qinghua zhang Linghui zhang Qian Song Wei Zhou Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin300072China Institute of Energy Hefei Comprehensive National Science CenterHefei230000China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China

A series of carbon-based binary single-atom catalysts of Fe and Ni coordinated by nitrogen are fabricated using a glucose-chelating *** on the Ni/Fe content,they exhibit a wide-range of controllable CO/H2 ratio from 0.14 to 10.86,which is meaningful to specific chemical *** durability of the catalyst is evaluated over an 8-hour period with no significant degradation of *** variation of the faradaic efficiency with Ni/Fe content is justified by density-functional-theory based calculation of the reaction barrier in both hydrogen evolution and CO2 reduction reactions.

关键词： CO2 reduction syngas binary single-atom catalyst electrocatalysis

Occurrence and distribution of hexabromocyclododecane in sediments from seven major river drainage basins in China

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Journal of Environmental Sciences 2013年第1期25卷 69-76页

作者： Honghua Li Hongtao Shang Pu Wang Yawei Wang Haidong zhang qinghua zhang Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

The concentrations and geographical distribution of hexabromocyclododecane （HBCD） were investigated in 37 composite surface sediments from seven major river drainage basins in China, including Yangtze River, Yellow River, Pearl River, Liaohe River, Haihe River, Tarim River and Ertix River. The detection frequency of HBCD was 54%, with the concentrations ranged from below limit of detection （LOD） to 206 ng/g dry weight. In general, the geographical distribution showed increasing trends from the upper reaches to the lower reaches of the rivers and from North China to Southeast China. Compared to other regions in the world, the average concentration of HBCD in sediments from Yangtze River drainage basin was at relatively high level, whereas those from other six river drainage basins were at lower or similar level. The highest HBCD concentration in sediment from Yangtze River Delta and the highest detection frequency of t-IBCD in Pearl River drainage basins suggested that the industrial and urban activities could evidently affect the HBCD distribution. HBCD diastereoisomer profiles showed that y-HBCD dominated in most of the sediment samples, followed by ct- and [3-HBCD, which was consistent with those in the commercial HBCD mixtures. Further risk assessment reflected that the average inventories of HBCD were 18.3, 5.87, 3.92, 2.50, 1.77 ng/cm2 in sediments from Pearl River, Haihe River, Tarim River, Yellow River and Yangtze River, respectively.

关键词： HBCD surface sediment Chinese river drainage basin distribution

Machine Learning-Assisted High-Throughput Virtual Screening for On-Demand Customization of Advanced Energetic Materials

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Engineering 2022年第3期8卷 99-109页

作者： Siwei Song Yi Wang Fang Chen Mi Yan qinghua zhang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Finding energetic materials with tailored properties is always a significant challenge due to low research efficiency in trial and ***,a methodology combining domain knowledge,a machine learning algorithm,and experiments is presented for accelerating the discovery of novel energetic materials.A high-throughput virtual screening(HTVS)system integrating on-demand molecular generation and machine learning models covering the prediction of molecular properties and crystal packing mode scoring is *** the proposed HTVS system,candidate molecules with promising properties and a desirable crystal packing mode are rapidly targeted from the generated molecular space containing 25112 ***,a study of the crystal structure and properties shows that the good comprehensive performances of the target molecule are in agreement with the predicted results,thus verifying the effectiveness of the proposed *** work demonstrates a new research paradigm for discovering novel energetic materials and can be extended to other organic materials without manifest obstacles.

关键词： Energetic materials Machine learning High-throughput virtual screening Molecular properties Synthesis

Research progress on gel polymer electrolytes for lithium-sulfur batteries

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Journal of Energy Chemistry 2021年第5期30卷 420-437页

作者： Jie Qian Biyu Jin Yuanyuan Li Xiaoli Zhan Yang Hou qinghua zhang College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027ZhejiangChina Institute of Zhejiang University-Quzhou Quzhou 324000ZhejiangChina

Lithium-sulfur(Li-S)batteries have become a promising candidate for advanced energy storage system owing to low cost and high theoretical specific *** the last decade,in pursuit of Li-S batteries with enhanced safety and energy density,the investigation on the electrolytes has leaped form liquid organic electrolytes to solid polymer ***,such solid-state Li-S battery system is greatly limited by unfavorable ionic conductivity,poor interfacial contact and narrow electrochemical windows on account of the absence of any liquid *** address these issues,gel polymer electrolytes(GPEs),the incorporation of liquid electrolytes into solid polymer matrixes,have been newly *** the excellent ionic transport and low interfacial resistance provided by GPEs have prompted numerous researchers to make certain progress on high-performance Li-S coins,a comprehensive review on GPEs for Li-S batteries remains ***,this review focuses on recent development and progress on GPEs in view of their physical and chemical properties for the applications in Li-S *** on the components including solid hosts,liquid solutions and fillers of GPEs are systematically summarized with particular emphasis on the relationship between components and ***,current challenges and directional outlook for fabricating GPEs-based Li-S batteries with outstanding performance are outlined.

关键词： Lithium-sulfur batteries Gel polymer electrolytes Solid hosts Liquid solutions

Historical trends of PCBs and PBDEs as reconstructed in a lake sediment from southern Tibetan Plateau

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Journal of Environmental Sciences 2020年第12期32卷 31-38页

作者： Ruiqiang Yang Ting Xie Pu Wang Yingming Li qinghua zhang Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310024China University of Chinese Academy of Sciences Beijing 100049China Institute of Environment and Health Jianghan UniversityWuhan 430056China

High-altitude lake sediment can be used as a natural archive to reconstruct the history of pollutants. In this work, the temporal distribution of polychlorinated biphenyls(PCBs) and polybrominated diphenyl ethers(PBDEs) were determined using a high-resolution gas chromatography coupled with high-resolution mass spectrometer(HRGC/HRMS) in an alpine lake sediment core collected from the southern Tibetan Plateau(TP) to examine whether the expected decreasing trends due to the implementation of the international Conventions could be observed. The concentrations of PCBs and PBDEs in the sediment core were in the range of 11.8–142 pg/g dw and ND-457 pg/g dw, and their fluxes were in the range of 2.51–31.7 ng/(m^2 ·yr) and ND-43.2 ng/(m^2 ·yr), respectively. The prevalence of low-chlorinated(tri-CB) PCBs and low-brominated(tri-to tetra-) PBDEs in most sections of the sediment profiles was observed, suggesting that the light molecular weight PCBs and PBDEs have most likely reached lake sediments by long-range atmospheric transport from distant sources. Despite the restrictions on their applications, the sediment records for the concentrations and fluxes showed no corresponding decreasing trend with restrictions for PCBs, which suggested that these POPs(e.g., PCBs) were still emitted to the environment owing to the influence of primary or secondary emissions. To our knowledge, this is the first report on input history of atmospheric PCBs and PBDEs recorded in TP Lake sediment.

关键词： Persistent organic pollutants(POPs) PCBs PBDEs Sediment core Historical trend Tibetan Plateau