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Joint probability distribution of winds and waves from wave simulation of 20 years (1989-2008) in Bohai Bay

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Water Science and Engineering 2013年第3期6卷 296-307页

作者： Xiao-chen YANG qing-he zhang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

The joint probability distribution of wind speed and significant wave height in the Bohai Bay was investigated by comparing the Gurnbel logistic model, the Gumbel-Hougaard （GH） copula function, and the Clayton copula function. Twenty years of wind data from 1989 to 2008 were collected from the European Centre for Medium-Range Weather Forecasts （ECMWF） database and the blended wind data of the Quick Scatterometer （QSCAT） satellite data set and re-analysis data from the United States National Centers for Environmental Prediction （NCEP）. Several typhoons were taken into account and merged with the background wind fields from the ECMWF or QSCAT/NCEP database. The 20-year data of significant wave height were calculated with the unstructured-grid version of the third-generation wind wave model Simulating WAves Nearshore （SWAN） under extreme wind process conditions. The Gumbel distribution was used for univariate and marginal distributions. The distribution parameters were estimated with the method of L-moments. Based on the marginal distributions, the joint probability distributions, the associated return periods, and the conditional probability distributions were obtained. The GH copula function was found to be optimal according to the ordinary least squares （OLS） test. The results show that wind waves are the prevailing type of wave in the Bohai Bay.

关键词： wind speed wave simulation joint probability distribution copula function,conditional probability distribution

Effects of organic matter and salinity on the flocculation of kaolinites in a settling column

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Journal of Hydrodynamics 2021年第1期33卷 150-156页

作者： Zhong-yue Li Jin-feng zhang qing-he zhang Xiao-teng Shen Tong-qing Chen State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration Tianjin UniversityTianjin 300350China Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210029China

The flocculation and the settling of the cohesive sediment play an important role in the sediment transport process,and they are affected by many *** the coasts and in the estuaries,the organic matter and the salinity are two significant *** this study,experiments are carried out to evaluate the flocculation and the settling of the kaolinite in cases of various organic matter and salinity solutions in quiescent *** optical multi-channel suspended concentration monitoring system is used to measure the sediment concentration and the floc *** results show that the settling velocity decreases with the increase of the organic matter content,and the floc size increases with the increase of the organic matter *** addition,an empirical formula for the settling velocity under the influence of the organic matter and the salinity based on the experimental results is proposed.

关键词： Kaolinite humic acid salinity settling velocity floc size distribution

An Improved H∞ Filter Design for Nonlinear System with Time-delay via T-S Fuzzy Models

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自动化学报 2010年第10期36卷 1454-1459页

作者： HUANG Sheng-Juan zhang Da-qing he Xi-Qin zhang Ning-Ning Science of School University of Science and Technology of Liaoning Anshan 114051 P. R. China

This paper is concerned with the filter design for nonlinear systems with time-varying delay via Takagi-Sugeno fuzzy model approach. Some sufficient conditions of the existence of fuzzy H ∞ filter are established through constructing an improved Lyapunov functional candidate, which could overcome the conservatism of the existing ones. The main technique used is the free weighting matrix method combined with a matrix decoupling approach. An illustrative example is given to show the effectiveness of the method

关键词：非线性系统自动化系统研究模糊性

Unified analytical solutions for a circular opening based on non-linear unified failure criterion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 71-79页

作者： Chang-guang zhang qing-he zhang Jun-hai ZHAO Fei XU Chuang-zhou WU MOE Key Laboratory of Geotechnical and Underground Engineering Tongji University Shanghai 200092 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China School of Civil Engineering Chang'an University Xi'an 710061 China Shanghai No. 1 Municipal Engineering Co. Ltd. Shanghai 200083 China

Unified analytical solutions are presented for the predictions of the stresses and displacements around a circular opening based on nonqinear unified failure criterion and the elastic-brittle-plastic softening model. Unified analytical solutions not only involve generally traditional solutions which are based on the Hock-Brown （H-B） failure criterion or the non-linear twin-shear failure criterion, but also involve other new results. The results of the radius of plastic zone, radial displacements and stresses are obviously different using three rock masses when different values of the unified failure criterion parameter or different material behavior models are used. For a given condition, the radius of plastic zone and radial displacements are reduced by increasing the unified failure criterion parameter. The latent potentialities of rock mass result from considering the effect of intermediate principal stress. It is shown that proper choices of the failure criterion and the material behavior model for rock mass are significant in the tunnel design.

关键词： Analytical solution Elastic-brittle-plastic rock Non-linear unified failure criterion Intermediate principal stress Dilatancy

Pheromone-trapping the nun moth, Lymantria monacha （Lepidoptera： Lymantriidae）in Inner Mongolia, China

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Insect Science 2017年第4期24卷 631-639页

作者： Peng Wang Guo-Fa Chen Jun-Sheng zhang Qi Xue Jin-Hua zhang Chao Chen qing-he zhang Station of Forest Pest Control and Quarantine Daxinganling Forestry Administration Yakeshi Inner Mongolia China General Station of Forest Pest control NFA Shenyang China Kuduer Forestry District Daxinganling Forestry Administration Kuduer Inner Mongolia China Wuerqihan Forestry District Daxinganling Forestry Administration Wuerqihan Inner Mongolia China Arshan Forestry District Daxinganling Forestry Administration Arshan Inner Mongolia China Sterling International Inc. Spokane Washington USA

The nun moth, Lymantria monacha L., is one of the most important defoliators of Eurasian coniferous forests. Outbreaks during 2011-2015 in the natural/planted larch, and larch-birch mixed forests of the Greater Khingan Range in Inner Mongolia, China, caused tremendous timber losses from severe defoliation and tree mortality. A series of trapping experiments were conducted in these outbreak areas to evaluate the efficacy of a synthetic species-specific pheromone lure based on the female pheromone blend of European nun moth populations. Our results clearly show that the nun moth in Inner Mongolia is highly and specifically attracted to this synthetic pheromone, with few gypsy moths （Lymantria dispar） captured. Flight activity monitoring ofL. monacha male moths using pheromone-baited Unitraps at 2 locations during the summer of 2015 indicated that the flight period started in mid-July, peaking in early August at both locations. Based on male moth captures, there was a strong diurnal rhythm of flight activity throughout the entire scotophase, peaking between 22：00 and 24：00. Unitraps and wing traps had significantly and surprisingly higher catches than the gypsy moth traps. Unitraps fastened to tree trunks 2 m above ground caught significantly more male moths than those at the ground level or at 5 m height. Male L. monacha moths can be attracted to pheromone- baited traps in open areas 150-200 m distant from the infested forest edge. Our data should allow improvement on the performance of pheromone-baited traps for monitoring or mass-trapping to combat outbreaks of this pest in northeastern China.

关键词： disparlure 2-methyl-(Z)-7-octadecene monachalure monitoring phero-mone trap

Field responses of the Asian larch bark beetle, Ips subelongatus, to potential aggregation pheromone components＂ disparity between two populations in northeastern China

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Insect Science 2011年第3期18卷 311-319页

作者： Li-Wen Song qing-he zhang Yue-Qu Chen Tong-Tong Zuo Bing-Zhong Ren School of Life Sciences Northeast Normal University Changchun Institute of Forest Protection Jilin Provincial Academy of Forestry Sciences Changchun China Sterling International Inc. Spokane Washington USA

Behavioral responses of the Asian larch bark beetle, lps subelongatus Motsch. to three potential aggregation pheromone components, ipsenol （racemic or [-]- enantiomer）, ipsdienol （racemic or [＋]-enantiomer） and 3-methyl-3-buten- l-ol, were tested using partial or full factorial experimental designs in two provinces （Inner Mongolia and Jilin） of northeastern China. Our field bioassays in Inner Mongolia （Larix principis- rupprechtii Mayr. plantation） clearly showed that ipsenol, either racemic or 97%-（-）- enantiomer, was the only compound that significantly attracted both sexes of 1. subelongatus, while all other compounds （singly or in combinations） were unattractive. There were no two- or three-way synergistic interactions. However, in Jilin Province （L. gmelini [Rupr.] Rupr. Plantation）, all the individual compounds tested were inactive, except a very weak activity by 97%-（-）-ipsenol in 2004 when the beetle population was very high. While a combination of ipsenol and ipsdienol （racemates or enantiomerically pure natural enantiomers） showed a significant attraction for both sexes of I. subelongatus, indicat- ing a two-way synergistic interaction between these two major components, addition of 3-methyl-3-buten-l-ol to these active binary blend（s） did not have any effects on trap catches, suggesting that ipsenol and ipsdienol are the synergistic aggregation pheromone components of I. subelongatus in Jilin Province. It seems that 97%-（-）-ipsenol in Inner Mongolia or the binary blend of 97%-（-）-ipsenol and 97%-（＋）-ipsdienol in Jilin Province are superior to their corresponding racemates, which might be due either to weak inhibitory effects of the antipode enantiomers or to reduced release rates of the active natural enan- tiomer（s） in the racemate（s）. Our current bioassay results suggest that there is a strong geographical variation in aggregation pheromone response of L subelongatus in northeastern China. Future research on the pheromone production and response of 1. s

关键词： aggregation pheromone enantiomers geographical variation Ips subelongatus ipsdienol ipsenol

Population divergence of aggregation pheromone responses in Ips subelongatus in northeastern China

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Insect Science 2016年第5期23卷 728-738页

作者： Da-Feng Chen Ye-Jing Li qing-he zhang Su-Fang zhang Hong-Bin Wang Zhen zhang Li-Lin Zhao Xiang-Bo Kong Key Laboratory of Forest Protection of State Forestry Administration Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China Sterling International Inc. Spokane Washington USA

The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern Chin

关键词： aggregation pheromone GC-EAD field trapping Ips subelongatus mtDNA-COI population divergence

Vertically grown MoS_(2)nanosheets on graphene with defect-rich structure for efficient sodium storage

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Rare Metals 2024年第3期43卷 1062-1071页

作者： Ying Wang Jia-Peng he Han-qing Pan qing-Peng Wang Lei zhang Yong-Chang Liu qing-Hong Wang School of Chemistry&Materials Science Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal UniversityXuzhou221116China Institute of Biopharmaceutical Research Liaocheng UniversityLiaocheng252059China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing100083China Centre for Catalysis and Clean Energy Gold Coast CampusGriffith UniversityGold CoastQLD4222Australia

The synthesis of a perpendicular growth structure of MoS_(2)nanosheets on graphene for efficient sodium storage is challenging yet ideal due to the benefits of open ion diffusion channels and high electronic *** this study,we have successfully fabricated a novel structure of vertical MoS_(2)nanosheets on graphene,with ZnS nanoparticles serving as bonding points(MoS_(2)/ZnS/G),through a facile hydrothermal *** the synthesis process,Zn^(2+)not only acts as a landing site for the vertical growth of MoS_(2)nanosheets but also triggers the formation of a defect-rich structure in the final *** unique architecture of MoS_(2)/ZnS/G effectively combines the advantages of a vertically aligned geometry and a defectrich structure for energy *** resulting structure displays shortened transport paths for electrons/ions,enhanced conductivity,improved structural integrity,and an increased number of active sites for promising electrochemical *** expected,when used as anode for sodium-ion batteries,the as-synthesize d MoS_(2)/ZnS/G exhibits excellent rate capability(high capacity of 298 mAh·g^(-1)at 5 A·g^(-1))and good cycling stability(a capacity decay of 0.056%per cycle after 500 cycles at 1 A·g^(-1)).According to the kinetic investigations,the electrochemical process of the MoS_(2)/ZnS/G sample is primarily governe d by a pseudocapacitive behavior,which enhances the charge/discharge kinetics and allows the MoS_(2)/ZnS/G structure to remain intact during cycling.

关键词： MoS_(2) Perpendicular growth Graphene Sodium storage Electrochemical performance

Physics of cavitation near particles

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Journal of Hydrodynamics 2024年第1期36卷 102-118页

作者： Jia-xin Yu Xiao-yu Wang Jun-wei Shen Jin-sen Hu Xiang-qing zhang Da-qing he Yu-ning zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The combined effect of cavitation and silt abrasion presents a great challenge and threat to secure the operation and the efficiency of hydraulic machineries working in sediment-laden *** present paper critically reviews the current research progress on the interaction mechanisms of the bubbles and the ***,the analytical models including boundary treatment methods for predicting the jet dynamics of the bubble collapse near particles are ***,the bubble collapsing dynamics,jet dynamics and shock wave characteristics near particles are revealed both experimentally and ***,the bubble-particle-wall system is investigated with a focus on microjets.

关键词： Cavitation bubble particle jet shock wave