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春小麦产量对不同气候年型的响应及其与品种干旱敏感性的关系

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南京农业大学学报 2025年第1期48卷 97-107页

作者：赵福年刘江杨红燕张强雷俊陈莉中国气象局兰州干旱气象研究所/甘肃省干旱气候变化与减灾重点实验室/中国气象局干旱气候变化与减灾重点开放实验室甘肃兰州730020 甘肃农业大学资源与环境学院甘肃兰州730070 聊城市农业技术推广服务中心山东聊城252000 定西市气象局甘肃定西743000 定西市农产品质量安全监测检测站甘肃定西743000

[目的]本研究旨在分析旱地春小麦产量增加的品种特性及其与气候条件的关系,为区域小麦品种选育和作物布局提供参考依据。[方法]在半干旱雨养农业区布设春小麦长期定位试验(雨养处理),开展不同播期以及播前和生育期间不同灌水处理试验,采... 详细信息

[目的]本研究旨在分析旱地春小麦产量增加的品种特性及其与气候条件的关系,为区域小麦品种选育和作物布局提供参考依据。[方法]在半干旱雨养农业区布设春小麦长期定位试验(雨养处理),开展不同播期以及播前和生育期间不同灌水处理试验,采用K-means聚类分析方法划分春小麦气候年型,并利用参数化后的春小麦生长发育模型设置不同气候情景,模拟研究半干旱区雨养春小麦产量对气候年型的响应及其与品种干旱敏感性之间的关系。[结果]春小麦生长发育的气候条件可以分为5个不同的年型,其主要由播前土壤含水量和生育期大气干湿程度(潜在蒸散与降水量之差)决定;所构建的春小麦模型对发育期、地上部生物量、收获指数以及产量的模拟值与实测值相比,一致性指数均大于0.8,相对均方根误差均小于30%。通过模型模拟发现,在播期与播前土壤含水量固定的情形下,当生育期降水量小于140 mm时,对干旱敏感的春小麦品种产量高于对干旱呈中性的品种,而在生育期降水量大于200 mm时,对干旱不敏感的春小麦品种产量最高。[结论]本研究所构建的春小麦模型能够较为准确地模拟春小麦发育期、地上部生物量、收获指数及产量形成。对干旱敏感的春小麦品种在极端干旱气候年型下更容易获得较高的产量,而对干旱不敏感的春小麦品种则在水分条件相对适宜的气候年型下容易高产。

关键词：作物模型春小麦等水和非等水性极端干旱气候年型

Flow-Induced Vibration of Four Cantilever Cylinders Arranged in A Square Configuration

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China Ocean Engineering 2021年第6期35卷 891-904页

作者： ZHU Hong-jun LIU Wen-li WANG jun-lei State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450000China

Flow-induced vibration(FIV)of four separately mounted cantilever cylinders are experimentally investigated in a water *** four cylinders with top ends screwed vertically into a turntable platform are subjected to uniform flows with Reynolds number ranging from 3840 to 16520.A non-intrusive measurement with high-speed cameras is employed to simultaneously capture the time-varying in-line and cross-flow vibrations in the reduced velocity range of *** results highlight the continuous adjustment of flow regime caused by the spatial-temporal alteration of ***,the space-time varying flow interference contributes to the occurrence of multiple response *** transition from a dominant frequency to a broad-band response illustrates the enhancement of wake *** combination of wake flow interactions results in the irregular oscillation trajectories and the appearance of a response trough with the associated switching in vortex shedding *** dual-resonance phenomenon is observed in the four cylinders due to the complicated wake-structure *** greatest mechanical energy possessed by the four cylinders in an in-line square arrangement is mainly resulted from the downstream cylinders,signifying the positive role of wake excitation in extracting hydrokinetic energy from ambient flow.

关键词： flow-induced vibration mechanical energy cantilever cylinder time-varying spacing attack angle

Aerodynamic stability of cable-supported bridges using CFRP cables

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 693-698页

作者： ZHANG Xin-jun YING lei-dong College of Civil Engineering and Architecture Zhejiang University of Technology Hangzhou 310014 China

To gain understanding of the applicability of carbon fiber reinforced polymer (CFRP) cable in cable-supported bridges, based on the Runyang Bridge and Jinsha Bridge, a suspension bridge using CFRP cables and a cable-stayed bridge using CFRP stay cables are designed, in which the cable’s cross-sectional area is determined by the principle of equivalent axial stiffness. Numerical investigations on the aerodynamic stability of the two bridges are conducted by 3D nonlinear aerodynamic stability analysis. The results showed that as CFRP cables are used in cable-supported bridges, for suspension bridge, its aerodynamic stability is superior to that of the case using steel cables due to the great increase of the torsional frequency; for cable-stayed bridge, its aerodynamic stability is basically the same as that of the case using steel stay cables. Therefore as far as the wind stability is considered, the use of CFRP cables in cable-supported bridges is feasible, and the cable’s cross-sectional area should be deter-mined by the principle of equivalent axial stiffness.

关键词： Cable-supported bridges Carbon fiber reinforced polymer (CFRP) cable Aerodynamic stability

The classification and assessment of vulnerability of man-land system of oasis city in arid area

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Frontiers of Earth Science 2013年第4期7卷 406-416页

作者： Chao GAO jun lei Fengjun JIN Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of Science Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Oasis city system is the center of the man-land relationship in arid area and it is the most influential spatial and temporal multiple dynamic system. Oasis city system is not only the largest area where artificial disturbances occur at a regional scale but also the most concentrated area of human activity in arid area. In this study, we developed an applicable and convenient method to assess vulnerability of man-land system of oasis cities with vulnerability indicator system, respectively evaluating the sensitivity, adaptability and vulnerability of the eco- environment system, the economic system and the social system. The results showed that the sensitivity and vulnerability of oasis cities in Xinjiang, China have significant differences while their adaptability does little. In order to find the inherent differences in the vulnerability of oasis cities, triangle methodology has been adopted to divide Xinjiang oasis cities into five types. Some adaptive developing policies specific for individual cities are also proposed based on their vulnerability type and constrain- ing factors.

关键词： vulnerability sensitivity man-land system,oasis cities arid area

An automatic optimization method for minimizing supporting structures in additive manufacturing

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Advances in Manufacturing 2020年第1期8卷 49-58页

作者： Xiao-jun Chen jun-lei Hu Qing-Long Zhou Constantinus Politis Yi Sun Institute of Biomedical Manufacturing and Life Quality Engineering State Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240P.R.China OMFS-IMPATH Research Group Department of Imaging and PathologyFaculty of MedicineKatholieke Universiteit LeuvenLeuvenBelgium Department of Oral and Maxillofacial Surgery University Hospitals LeuvenLeuvenBelgium

The amount of supporting structure usage has been a major research topic in layer-based additive manufacturing(AM)over the past years as it leads to increased fabrication time and decreased surface *** studies focused on deformation and topology optimization to eliminate the number of support ***,during the actual fabrication process,the properties of shape and topology are ***,they should not be modified *** this study,we present an optimizer that reduces the number of supporting structures by identifying the prime printing *** rotation,models are projected in each direction in space,and the basis units involved in the generation of support structures are ***,the area of the supporting structures is ***,the prime printing direction with minimal supporting area is obtained through pattern-searching *** results of the experiment demonstrated that the printing area was reduced by up to 60%for some cases,and the surface quality was also improved ***,both the material consumption and fabrication time were decreased in most *** future work,additional factors will be considered,such as the height of the supporting S Xiao-jun Chen xiaojunchen@*** 1 Institute of Biomedical Manufacturing and Life Quality Engineering,State Key Laboratory of Mechanical System and Vibration,School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,*** 2 OMFS-IMPATH Research Group,Department of Imaging and Pathology,Faculty of Medicine,Katholieke Universiteit Leuven,Leuven,Belgium 3 Department of Oral and Maxillofacial Surgery,University Hospitals Leuven,Leuven,Belgium structures and the adhesion locations to improve the efficiency of this optimizer.

关键词： Printing direction Optimization Supporting structures

Graphite-polypyrrole coated 316L stainless steel as bipolar plates for proton exchange membrane fuel cells

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 53-58页

作者： Li-jun Yang Hai-jun Yu Li-jun Jiang lei Zhu Xu-yu Jian Zhong Wang Energy Materials and Technology Research Institute Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

316L stainless steel（SS 316L） is quite attractive as bipolar plates in proton exchange membrane fuel cells（PEMFC）.In this study,graphite-polypyrrole was coated on SS 316L by the method of cyclic *** surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy（SEM） and X-ray photoelectron spectroscopy（XPS）.A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS *** current densities in the simulated PEMFC anode and cathode conditions are around 3×10-9 and 9×10-5 A·cm-2,*** addition,the interfacial contact resistance（ICR） was also *** ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS ***,graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.

关键词： proton exchange membrane fuel cells polypyrrole graphite corrosion contact resistance stainless steel

Tungsten disulfide: synthesis and applications in electrochemical energy storage and conversion

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Tungsten 2020年第3期2卷 217-239页

作者： Wen lei jun‑lei Xiao Hai‑Peng Liu Quan‑Li Jia Hai‑jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Henan Key Laboratory of High Temperature Functional Ceramics Zhengzhou UniversityZhengzhou 450052China

Recently,two-dimensional transition metal dichalcogenides,particularly WS_(2),raised extensive interest due to its extraordi-nary physicochemical *** the merits of low costs and prominent properties such as high anisotropy and distinct crystal structure,WS_(2) is regarded as a competent substitute in the construction of next-generation environmentally benign energy storage and conversion *** this review,we begin with the fundamental studies of the structure,properties and preparation of WS_(2),followed by detailed discussions on the development of various WS_(2) and WS_(2)-based composites for electrochemical energy storage and conversion *** the end,some prospective prospects and promising develop-ments of WS_(2) in these fields are proposed.

关键词： Transition metal dichalcogenides Tungsten disulfide Exfoliation Energy storage and conversion

Oasis System and Its Reasonable Development in Sangong River Watershed in North of the Tianshan Mountains,Xinjiang,China

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Chinese Geographical Science 2006年第3期16卷 236-242页

作者： lei jun LUO Geping ZHANG Xiaolei LU Qi Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources structure, vegetation structure, economic structure and their corresponding functions. The results indicate that as a typical small-scale watershed, Sangong River watershed has the relatively complete mountain-basin structure, and ecological and productive function. Because of human drastic activity the utilization rate of water resources was as high as 98.7%, and the utilization of groundwater was not reasonable, which resulted in an average annual decline of 0.353m in the water table of alluvial-diluvial-fan oasis, and an average annual increase of 0.047m in the alluvial-plain. The layout of crop and shelter forest benefits to the utilization of water and land resources. The development of oasis economy is at low level, and its eco-economic function is weak.

关键词： oasis structure oasis function oasis economy Sangong River watershed

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang jun-lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

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