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Research on design of adaptive connecting mechanisms for the cable-net and panels of FAST

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Research in Astronomy and Astrophysics 2017年第9期17卷 119-130页

作者： Peng Jiang qing-Wei Li ren-Dong Nan National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Key Laboratory of Radio Astronomy Beijing 100012China

The reflector system of the Five-hundred-meter Aperture Spherical radio Telescope （FAST） is designed to incorporate 4450 rigid panels supported by a flexible cable-net structure. The shapechanging operation that occurs in the process of observation will lead to a relative displacement between adjacent nodes in the cable-net. In addition, three nodes on a rigid panel are fixed with respect to each other. Thus, adaptive connecting mechanisms between panels and the cable-net are certainly needed. The present work focuses on the following aspects. Firstly, the degrees of freedom of adaptive connecting mechanisms were designed so that we can not only adapt the panel to the deformation of the cable- net, but also restrict the panel to its right place. Secondly, finite element and theoretical analyses were applied to calculate the scope of motion in adaptive connecting mechanisms during the cable-net＇s shape-changing operation, thus providing input parameters for the design size of the adaptive connecting mechanisms. In addition, the gap size between the panels is also investigated to solve the trade-off between avoiding panel collisions and increasing the observation efficiency of FAST.

关键词： telescopes -- Astronomical Instrumentation, Methods and Techniques -- methods ana-lytical -- methods data analysis

3D Effects on Vortex-Shedding Flow and Hydrodynamic Coefficients of A Vertically Oscillating Cylinder with A Bottom-Attached Disk

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China Ocean Engineering 2017年第4期31卷 428-437页

作者： WANG Quan KOU Yu-feng ZHU ren-qing CHEN Hong State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and deep-Sea Exploration Shanghai 200240China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhengjiang 212002China Shanghai Waigaoqiao Shipbuilding CO. LTD.Shanghai 200240China

Vortex-shedding flow induced by the vertical oscillation of a cylinder with bottom-attached disks of different diameter ratio Dd/Dc and thickness ratio td/Dc is studied by a 3D （three-dimensional） numerical model developed in this paper, and compared with the results obtained through 2D （two-dimensional） numerical model. The high-order upwind scheme is applied to stabilize the computation, and convergence is accelerated by the multi-grid method. Qualitative and quantitative analyses of the differences between the 2D and 3D simulation results reveal the 3D effect on the flow field characteristics and hydrodynamic coefficients of the vertically oscillating cylinder with a bottom-attached disk. The 3D effect on the fluid field is mainly reflected in the significance of three vortex-shedding patterns： ωx has a greater effect on the flow fields around the sharp edges relative to the vortices generated in the 2D simulation. In the slice along the axial orientation, the vortex effect of ωy along the radial axis is smaller than that of ωx along the circumferential direction, indicating the radial effect on the velocity more pronounced than the circumferential effect around the sharp edges of the disk. The rotational interaction ωz of the fluid in the horizontal plane during the heave motion is insignificant. Based on the 2D and 3D simulation results, the turning points that separate the increasing regimes of the added mass coefficient and damping ratio are identified. The dependence of the turning point on the diameter ratio Dd/Dc and thickness ratio td/Dc are discussed in detail.

关键词： 3D effect vortex-shedding pattern added mass coefficient damping ratio vertical oscillation

detection and projection of climatic comfort changes in China's mainland in a warming world

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Advances in Climate Change Research 2022年第4期13卷 507-516页

作者： Jin-Tao ZHANG Guo-Yu ren qing-Long YOU Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China National Climate Center China Meteorological Administration Beijing 100081China department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China department of Atmospheric Science School of Environmental StudiesChina University of GeosciencesWuhan 430074China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China

Climatic comfort,which refers to the comfort of the human body's thermal sensations,is important for the human *** considerable efforts have been provided to examine changes in climatic comfort response to global warming from a partial perspective,the trajectory shift in past and future climatic comfort conditions in China's mainland based on uniform indicators has not been *** spatiotemporal pattern of climatic comfort over historical and future periods was investigated in this study,using China's mainland as an *** temperature-humidity index was adopted on the basis of homogenised meteorological station observations and high-resolution climate model simulations to analyse the trends of comfort/discomfort days from 1960 to 2017 and project changes in climatic comfort under representative concentration pathway scenarios in the late 21st century(2071-2100).Results show a substantial decrease in colduncomfortable days and a moderate increase in comfortable and warm-uncomfortable days from 1960 to *** the late 21st century,the signals of increasing warm-uncomfortable and decreasing cold-uncomfortable days are projected to enhance significantly while the direction of changes in comfortable days exhibits a north-south *** uneven changes in warm-and cold-uncomfortable days and an overall decrease in comfortable days in the late 21st century dominate the future trends in climatic comfort in the densely populated southeast half of *** measures taken for adapting to and mitigating global climate warming can considerably avoid the adverse impact of the projected change.

关键词： Comfort Climate change Temperature-humidity index Projection China's mainland

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基于复杂网络的全球铜产业持股结构研究

中国矿业 2025年第2期34卷 346-359,2页

作者：孟子钰李华姣任帅刘妍心管青安鹏丽中国地质大学(北京)经济管理学院北京100083 自然资源部资源环境承载力评价重点实验室北京100083 首都经济贸易大学管理工程学院北京100070 中国地质大学(北京)信息工程学院北京100083 中国地质大学(武汉)管理科学与工程系湖北武汉430074

随着铜资源在全球经济中的战略重要性不断上升,各国通过投资和并购来强化自身在铜资源领域的地位。传统上,直接持有上市公司的股份是增强影响力的主要方式。然而近年来,间接持股形式逐渐兴起,使得利益分配和实际控制权变得更为复杂且不... 详细信息

随着铜资源在全球经济中的战略重要性不断上升,各国通过投资和并购来强化自身在铜资源领域的地位。传统上,直接持有上市公司的股份是增强影响力的主要方式。然而近年来,间接持股形式逐渐兴起,使得利益分配和实际控制权变得更为复杂且不透明。因此,本文研究旨在解析这种转变,并识别出在全球铜产业中占据关键位置的国家。本文研究采用了复杂网络分析的方法论,对来自OSIRIS数据库的主要股东持股信息进行了系统性分析。这不仅包括直接持股比例的数据,还涵盖了间接持股路径的追踪,从而全面了解不同国家在全球铜产业中的角色。研究结果表明,间接持股关系的增长削弱了地理因素和政治因素的传统影响,使股东背景更加国际化。美国在直接持股方面保持领先地位,而意大利和新加坡则在间接持股领域显示出了显著的影响力。资源丰富的国家倾向于通过直接持股巩固其矿产所有权,而非资源国更多地采用间接持股策略以提升其市场地位。本文研究揭示了全球铜产业内部隐含的所有权动态,即非资源国通过间接持股增强了在全球市场的影响力,而资源国则继续依赖于直接持股来维持其优势。这一发现对于理解国际资本流动的新模式具有重要意义,并为政策制定者提供了宝贵的视角,鼓励其采取措施促进对铜产业的投资,进而提升各自国家在全球铜市场上的竞争力。此外,研究突出了复杂网络分析方法在探索跨国企业间隐蔽联系方面的应用潜力,为未来类似研究提供了一个新框架。

关键词：铜产业持股关系复杂网络直接持股间接持股

development of gated fiber detectors for laser-induced strong electromagnetic pulse environments

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Nuclear Science and Techniques 2021年第6期32卷 36-44页

作者： Po Hu Zhi-Guo Ma Kai Zhao Guo-Qiang Zhang de-qing Fang Bao-ren Wei Chang-Bo Fu Yu-Gang Ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

With the development of laser technologies,nuclear reactions can happen in high-temperature plasma environments induced by lasers and have attracted a lot of attention from different physical ***,studies on nuclear reactions in plasma are still limited by detecting *** is mainly due to the fact that extremely high electromagnetic pulses(EMPs)can also be induced when high-intensity lasers hit targets to induce plasma,and then cause dysfunction of many types of traditional ***,new particle detecting technologies are highly *** this paper,we report a recently developed gated fiber detector which can be used in harsh EMP *** this prototype detector,scintillating photons are coupled by fiber and then transferred to a gated photomultiplier tube which is located far away from the EMP source and shielded *** those measures,the EMPs can be avoided which may result that the device has the capability to identify a single event of nuclear reaction products generated in laser-induced plasma from noise EMP *** new type of detector can be widely used as a time-of-flight(TOF)detector in high-intensity laser nuclear physics experiments for detecting neutrons,photons,and other charged particles.

关键词： Gated fiber detector Radiation detection High-intensity laser Strong electromagnetic pulses

Gravitational deformation Measurement Method for the Main Reflector and Sub-reflector of the 70 m Antenna by Laser Scanner

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Research in Astronomy and Astrophysics 2022年第9期22卷 1-9页

作者： Lian-Bo Fu Jian-Jun Liu Wei Yan de-qing Kong Xin ren Chen-Di Liu Hong-Bo Zhang Key Laboratory of Lunar and dep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBejing 100101China Urunaivreyr of Chinese Academy of Sciences Beijing 100049China

Large antennas play an important role in deep space exploration and astronomical research. However, their performances are inevitably affected by the main reflector surface deformation and sub-reflector displacement resulting from the factors of wind, temperature, and gravity, among which the effect of gravity is especially pronounced. In this work, a three-dimensional laser scanner was employed to measure the main reflector and subreflector gravitational deformation of the Tianjin 70 m antenna at different elevation angles. Here, we solved the antenna main reflector deformation and sub-reflector displacement, and analyzed the deformation law of the antenna under the action of gravity. A new measurement method of antenna main reflector deformation and subreflector displacement is realized by mutual verification of the measured results and theoretical simulations. This method will help to improve the antenna performance and provide a reference to optimize the design of largeaperture antennas.

关键词： telescopes techniques:radar astronomy planets and satellites:detection

Combustion Characteristics and Kinetics of Anthracite Blending with Pine Sawdust

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Journal of Iron and Steel Research International 2015年第9期22卷 812-817页

作者： Guo-qing LIU qing-cai LIU Xiao-qing WANG Fei MENG Shan ren Zhen-peng JI College of Materials Science and Engineering Chongqing University

The combustion characteristics and kinetics of anthracite,pine sawdust and their blends were investigated under combustion condition by thermogravimetric analysis,*** fractions of pine sawdust in the blended samples were set to be 30%,50%,and 80%.The results showed that the ignition and burnout temperatures of pine sawdust were lower and the maximum combustion rate was higher than those of *** the increase of pine sawdust content,the ignition temperature and burnout temperature of the blends decreased,while the maximum mass loss rate and the combustible index of the blends increased;that is,the comprehensive combustion property became *** kinetic parameters for the blends combustion under air condition were calculated based on experimental results using Coats-Redfern *** the pine sawdust content varied in the range of 30%-80%,the combustion processes of these blends could be divided into two stages and the combustion reactions belong to the first-order *** values of apparent activation energy at two individual stages decreased from 68.78to47.28kJ·mol-1 and from 113.53 to 46.43kJ·mol-1,respectively.

关键词： pine sawdust anthracite thermogravimetric analysis combustion characteristics apparent activation energy

基于漆酶一步催化法的羊毛织物原位染色及阻燃功能化

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纺织学报 2025年第2期46卷 161-169页

作者：郭庆毛阳顺任亚杰刘济民王怀芳朱平青岛大学纺织服装学院山东青岛266071 青岛大学功能纺织品与先进材料研究院山东青岛266071 青岛大学生物多糖纤维成形与生态纺织国家重点实验室山东青岛266071

针对羊毛织物的传统染色及阻燃整理工艺流程复杂、条件苛刻、损伤织物并可能污染环境等问题,采用生物酶法,以没食子酸(GA)和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为底物,通过漆酶催化作用,在温和条件下采用一步法在羊毛织物上同... 详细信息

针对羊毛织物的传统染色及阻燃整理工艺流程复杂、条件苛刻、损伤织物并可能污染环境等问题,采用生物酶法,以没食子酸(GA)和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为底物,通过漆酶催化作用,在温和条件下采用一步法在羊毛织物上同步实现染色和阻燃功能化。借助紫外-可见光谱仪、测色仪、氧指数仪、扫描电子显微镜、能量色散谱仪及红外光谱仪等对GA、DOPO、GA/DOPO混合物反应液及其处理后织物的形貌和化学组成进行测试与表征,对GA与DOPO及羊毛的反应机制进行分析,并对处理后织物的染色性能、阻燃性能、热稳定性、强力及手感性能等进行测试。结果表明:GA与DOPO之间能够发生共聚反应,并与羊毛通过接枝交联附着在羊毛织物表面,赋予其一定牢度的颜色与阻燃性能;经GA和DOPO共同处理后羊毛织物呈褐色,K/S值达到4.98,极限氧指数达到27.5%,织物强力较未处理羊毛提升46%左右,且处理得到的织物样品仍保持羊毛优良的手感。

关键词：漆酶没食子酸 9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物羊毛织物染色阻燃功能纺织品

On a Generalized Extended F-Expansion Method

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Communications in Theoretical Physics 2006年第1期45卷 15-28页

作者： ren Yu-Jie LIU Shu-Tian ZHANG Hong-qing department of Applied Mathematics Dalian University of Technology Dalian 116024 China department of Mathematics and Physics Dalian Institute of Light Industry Dalian 116034 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China

Making use of a new generalized ansatz, we present a new generalized extended F-expansion method for constructing the exact solutions of nonlinear partial differential equations in a unified way. Applying the generalized method with the aid of Maple, we consider the （2＋1）-dimentional breaking soliton equation. As a result, we successfully obtain some new and more general solutions including Jacobi elliptic function solutions, soliton-like solutions, trigonometric function solutions, and so on. As an illustrative sampler the properties of some soliton solutions for the breaking soliton equation are shown by some figures. Our method can also be applied to other partial differential equations.

关键词： (2+1)-dimentional breaking soliton equation generalized extended F-expansion method Jacobi elliptic function solution generalized ansatz soliton-like solution