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过氧钛钨硅杂多配合物的合成、表征及催化活性

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化学学报 1998年第7期56卷 700-706页

作者：单秋杰龚剑石绍庆瞿伦玉东北师范大学化学系长春130024

合成了过氧钛钨硅杂多酸盐α-M_(6-m)H_m[SiW_(11)(TiO_2)O_(39)]·xH_2O和α-M_(10-m)H_m[SiW_9(TiO_2)_3O_(37)]·xH_2O(M=K,TBA),用IR,UV吸收光谱,极谱-循环伏安,^(183)W NMR,XPS和XRD等测试方法对其性质、结构进行研究.结果表明,它们都是具有Keggin结构的过氧杂多配合物,TiO_2基团的引人将其极谱半波电位提高至-0.3V以上,它们对顺丁烯二酸的H_2O_2环氧化反应具有显著高的催化活性.

关键词：过氧钛钨硅杂多酸盐催化剂环氧化顺丁烯二酸

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聚合物热裂解碳材料结构对电化学性能的影响

高等学校化学学报 2000年第7期21卷 1110-1112页

作者：谢忠巍张喜艳田玉美龚剑曲晓光瞿伦玉东北师范大学化学学院长春130024

Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rather loose structure of molecular size order with an interlayer distance of 0.36—0.37 nm. Using electrochemical methods, we have studied the insertion of lithium within these materials. Resole resins, heated to 580 ℃, have a reversible capacity of about 400 mA·h/g, which is beyond the theoretical capacity of graphite（372 mA·h/g） and discover that carbons with a smaller crystallite size and large interlayer distance have the larger discharge capacity.

关键词：酚醛树脂裂解碳阳极锂离子电池电化学性能

Navigating the Challenges of Emerging Contaminants to Protect Human and Ecological Health

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Engineering 2024年第6期37卷 1-2页

作者： Jiuhui qu Michael R.Hoffmann Gang yu School of Environment Tsinghua UniversityBeijing 100084China Linde-Robinson Laboratories California Institute of TechnologyPasadenaCA 91125USA Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

Emerging contaminants are defined as chemicals that are not currently(or have only recently been)regulated and about which there are concerns regarding their impact on human or ecological *** contaminants are widely detected in air,water,soil,sediment,and biotic *** is against this backdrop of urgency that we have curated this special issue titled“Emerging Contaminants Control:Science and Technology,”with the goal of uniting the latest scientific insights and pioneering strategies to address this global *** special issue embarks on a comprehensive examination of the emerging contaminants dilemma,covering aspects such as risk assessment,remediation technologies,environmental surveying,and the broader implications for *** a collection of articles,we probe deep into the core of this issue,showcasing studies that range from appraising environmental risks to forging new methods for treatment and scrutinizing the occurrence of contaminants across different environmental settings.

关键词： Ecological surveying environmental

Promoting Environmental Risk Assessment and Control of Emerging Contaminants in China

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Engineering 2024年第6期37卷 13-17页

作者： Bin Wang Qian Sui Huijuan Liu Gang yu Jiuhui qu School of Environment Tsinghua UniversityBeijing 100084China School of Resources and Environmental Engineering East China University of Science and TechnologyShanghai 200237China Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

*** In recent years,China has carried out an extensive preventative battle against air,water,and soil pollution,and the nation’s environmental quality-as reflected by conventional pollutant indicators—has significantly *** the same time,the issue of emerging contaminants(ECs)is beginning to receive increasing *** generally refer to newly discovered or noticeable pollutants that pose risks to the ecological environment or human *** they have not been included in environmental management,or existing management measures are insufficient to effectively prevent and control their *** ECs of greatest concern generally include persistent organic pollutants(POPs),endocrine-disrupting chemicals(EDCs),pharmaceuticals and personal care products(PPCPs),and *** four categories of ECs are not entirely separate,as they interrelate with each other(Fig.1).Chemical production and product usage are the main sources of *** is the world’s largest producer and consumer of bulk chemicals,and the production value of China’s chemical industry is predicted to reach 50%of the global total by 2030[1].Scientific control of ECs based on their environmental risk assessment is a necessary way to support the prevention and legal governance of ECs.

关键词： legal entirely prevention

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi yu Wan-li WANG Pi-guang qu Yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action

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China Ocean Engineering 2024年第1期38卷 54-67页

作者： WANG Pi-guang Lyu Si-yu qu Yang ZHAO Mi DU Xiu-li State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Tech-nologyBeijing 100124China

This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water *** governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible *** governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary *** analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite *** main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion *** added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering *** calculation results show that the simplified formulas are in good agreement with the analytical solutions.

关键词： earthquake hydrodynamic pressure truncated cylinder added mass simplified formula

十一钨锌杂多配合物位置异构体的合成、表征及催化性能

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无机化学学报 2000年第4期16卷 688-692页

作者：马荣华刘春涛瞿伦玉齐齐哈尔大学化学化工学院齐齐哈尔161006 齐齐哈尔市环境监测中心站齐齐哈尔161005 东北师范大学化学系长春130024

The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR and X... 详细信息

关键词：十一钨锌杂多酸盐异构体催化活性合成催化剂

Three-Dimensional Density Distribution and Seismic Activity along the Guxiang–Tongmai Segment of the Jiali Fault,Tibet

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 454-467页

作者： FAN Pengxiao yu Changqing WANG Ruixue ZENG Xiangzhi qu Chen ZHANG yue Institute of Land and Resources Engineering Kunming University of Science and Technology Kunming 650000China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Jiangsu Donghai Continental Deep Hole Crustal Activity National Observation and Research StationLianyungangJiangsu 222000China

The Guxiang-Tongmai segment of the Jiali fault is situated northeast of the Namche Barwa Syntaxis in northeastern *** is one of the most active strike-slip faults near the syntaxis and plays a pivotal role in the examination of seismic activity within the eastern Himalayan *** study in the research region has yielded a 1:200000 gravity dataset covering an area 1500 km^(2).Using wavelet transform multiscale decomposition,scratch analysis techniques,and 3D gravity inversion methods,gravity anomalies,fault distributions,and density structures were determined across various *** the integration of our new gravity data with other geophysical and geological information,our findings demonstrate substantial variations in the overall crustal density within the region,with the fault distribution closely linked to these density *** in stratigraphic density are important causes of variations in the capacity of geological formations to endure regional tectonic *** are predominantly concentrated within the density transition zone and are primarily situated in regions of elevated *** hanging wall stress within the Guxiang-Tongmai segment of the Jiali fault exhibits a notable concentration,marked by pronounced anisotropy,and is positioned within the density differential zone,which is prone to earthquakes.

关键词： seismicity deep-density structure wavelet transform multi-scale decomposition scratch analysis 3D gravity inversion Jiali fault Tibet

Constraints Separation Based Evolutionary Multitasking for Constrained Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1819-1835页

作者： Kangjia Qiao Jing Liang Kunjie yu Xuanxuan Ban Caitong yue Boyang qu Ponnuthurai Nagaratnam Suganthan School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China School of Electrical Engineering and Automation Henan Institute of TechnologyXinxiang 453003China School of Electronic and Information Zhongyuan University of TechnologyZhengzhou 450007China KINDI Center for Computing Research College of EngineeringQatar UniversityDoha 999043Qatar

Constrained multi-objective optimization problems(CMOPs)generally contain multiple constraints,which not only form multiple discrete feasible regions but also reduce the size of optimal feasible regions,thus they propose serious challenges for *** all constraints,some constraints are highly correlated with optimal feasible regions;thus they can provide effective help to find feasible Pareto ***,most of the existing constrained multi-objective evolutionary algorithms tackle constraints by regarding all constraints as a whole or directly ignoring all constraints,and do not consider judging the relations among constraints and do not utilize the information from promising single ***,this paper attempts to identify promising single constraints and utilize them to help solve *** be specific,a CMOP is transformed into a multitasking optimization problem,where multiple auxiliary tasks are created to search for the Pareto fronts that only consider a single constraint ***,an auxiliary task priority method is designed to identify and retain some high-related auxiliary tasks according to the information of relative positions and dominance ***,an improved tentative method is designed to find and transfer useful knowledge among *** results on three benchmark test suites and 11 realworld problems with different numbers of constraints show better or competitive performance of the proposed method when compared with eight state-of-the-art peer methods.

关键词： Constrained multi-objective optimization(CMOPs) evolutionary multitasking knowledge transfer single constraint.