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An adjustment method for active reflector of large high-frequency antennas considering gain and boresight

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Research in Astronomy and Astrophysics 2017年第5期17卷 39-50页

作者： Cong-Si Wang Lan Xiao Wei Wang Qian Xu Bin-Bin Xiang Jian-Feng Zhong Li Jiang Hong Bao Na Wang Key Laboratory of Electronic Equipment Structure Design Ministry of EducationXidian UniversityXi'an710071China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Huawei Technologies Co. Ltd.Shenzhen 518129China Nanjing Research Institute of Electronics Technology Nanjing 210039China CETC No.39 Research Institute Xi'an 710065China

The design of the Qitai 110 m Radio Telescope（QTT） with large aperture and very high working frequency（115 GHz） was investigated in Xinjiang, china. The results lead to a main reflector with high surface precision and high pointing precision. In this paper, the properties of active surface adjustment in a deformed parabolic reflector antenna are analyzed. To assure the performance of large reflector antennas such as gain and boresight, which can be obtained by utilizing an electromechanical coupling model, and satisfy them simultaneously, research on active surface adjustment applied to a new parabolic reflector as target surface has been done. Based on the initial position of actuators and the relationship between adjustment points and target points, a novel mathematical model and a program thatdirectly calculates the movements of actuators have been developed for guiding the active surface adjustment of large reflector antennas. This adjustment method is applied to an 8 m reflector antenna,in which we only consider gravity deformation. The results show that this method is more efficient in adjusting the surface and improving the working performance.

关键词： adjustment reflector antenna pointing deformed utilizing gravity adjusting considering guiding

Bimodal microstructure – A feasible strategy for high-strength and ductile metallic materials

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Journal of Materials science & Technology 2018年第2期34卷 257-264页

作者： Min Zha Hong-Min Zhang Zhi-Yuan Yu Xuan-He Zhang Xiang-Tao Meng Hui-Yuan Wang Qi-Chuan Jiang State Key Laboratory of Automotive Simulation and Control Jilin University Key Laboratory of Automobile Materials of Ministry of Education & School of Materials science and Engineering Nanling Campus Jilin University

Introducing a bimodal grain-size distribution has been demonstrated an efficient strategy for fabricating high-strength and ductile metallic materials, where fine grains provide strength, while coarse grains enable strain hardening and hence decent ductility. Over the last decades, research activities in this area have grown enormously, including interesting results onfcc Cu, Ni and Al-Mg alloys as well as steel and Fe alloys via various thermo-mechanical processing approaches. However, investigations on bimodal Mg and other hcp metals are relatively few. A brief overview of the available approaches based on thermo- mechanical processing technology in producing bimodal microstructure for various metallic materials is given, along with a summary of unusual mechanical properties achievable by bimodality, where focus is placed on the microstructure-mechanical properties and relevant mechanisms. In addition, key factors that influencing bimodal strategies, such as compositions of starting materials and processing parameters, together with the challenges this research area facing, are identified and discussed briefly.

关键词： Nanocrystalline and ultrafine-grained metals Mechanical milling Severe plastic deformation Bimodal microstructure Strength and ductility

Isolation and identifi cation of antimicrobial metabolites from sea anemone-derived fungus Emericella ***01

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Journal of Oceanology and Limnology 2021年第3期39卷 1010-1019页

作者： Yang YUE Huahua YU Rongfeng LI Linfeng HU Song LIU Rong’e XING Pengcheng LI Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Drugs and Bioproducts Pilot Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China School of Chemistry and Chemical Engineering Henan Institute of Science and TechnologyXinxiang 453003China

Marine symbiotic fungi represent an intriguing source of discovery of novel secondary metabolites with various biological *** anemones are benthic marine invertebrates,however,the cultivable symbiotic fungi residing in the sea anemones are paid few attentions compared to those derived from their cnidarian *** we show the identification of antimicrobial secondary metabolites from the sea anemone-derived symbiotic *** offive isolated fungal strains,only the strain SMA01 showed strong antimicrobial activities,which was assigned into the genus Emericella based on the morphological characteristics and the ITS *** swift from liquid fermentation to solid rice medium presented little influence on its antibacterial activity.A chemical investigation of the ethyl acetate extract of the Emericella ***01 led to discovery of the primary antibiotic metabolite phenazine-1-carboxylic *** IC_(50) values of the phenazine-1-carboxylic acid against Phytophthora capsici,Gibberella zeae,and Verticillium dahliae were determined to be 23.26-53.89μg/*** the best of our knowledge,this was the first report of Emericella *** sea *** current study may benefit understanding of the defensive chemical interactions between the symbiotic fungi and their host sea anemones.

关键词： sea anemone symbiotic fungi phenazine-1-carboxylic acid antimicrobial activity

Research on the hierarchical structure of the metropolitan system and economic development of the provincial capital urban circle in Shandong

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Chinese Journal of Population,Resources and Environment 2015年第1期13卷 78-86页

作者： Xiaoyong Qiao Yanchun Meng Xiangyu Zhu School of Economics and Management Beijing University of Technology School of Public Policy and Management Tsinghua University

Regional development is the trend for future urbanization,and the urban circle is a highly efficient economic spatial pattern of regional *** study selects statistical data of urban area population,GDP,and the output value of tertiary industry for seven cities in china- Jinan,Zibo,Tai'an,Laiwu,Dezhou,Liaocheng,and Binzhou- in the Shandong provincial capital urban circle from 2005 to *** uses the principles and Zipf model,rank-size rule,and Lotka logarithmic model to analyze and study the hierarchical structure of the metropolitan system and economic development of the Shandong provincial capital urban *** on the above research,this paper provides references for decisionmaking on enhancement of the metropolitan system structure,improvement in core city primacy index,the optimal adjustment of industrial structure and the optimal allocation of essential resources.

关键词： hierarchical structure economic development metropolitan system Shandong provincial capital urban circle

Photoelectrochemical Biosensor for 5-Formylcytosine Based on WS_(2)/Bi/Bi_(2)O_(2)CO_(3) Nanocomposite and Rolling Circle Amplification

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Chinese Journal of Chemistry 2022年第2期40卷 247-255页

作者： Qian Wang Huanshun Yin Yunlei Zhou Lulu Cao Zhengkun Yu Yamin Xu Shiyun Ai College of Chemistry and Material science Food Safety Analysis and Test Engineering Technology Research Center of Shandong ProvinceShandong Agricultural UniversityTaianShandong 271018China

As a key epigenetic modification,5-formylcytosine(5fC)controls many important cell functions,such as gene expression and cell ***,5fC exists in mammalian tissues and cells with low content,and its structure is highly similar to 5-methylcytosine(5mC),5-hydroxymethylcytosine(5hmC)and 5-carboxycytosine(5caC), which requires the detection method for detecti ng 5fC with high sensitivity and *** this experiment,WS_(2)/Bi/Bi_(2)O_(2)CO_(3) was used as the photoactive material,5fC antibody was used as the target molecule recog nition reage nt,and rolling amplification(RCA)was employed as the signal amplification strategy to con struct a no vel photoelectrochemical biose nsor for detecti ng 5-formylcytosi ne deox ynu cleotide(SfdCTP).

关键词： Semicon ductors Photoelectrochemistry Biosensor Epigenetic modification Toxicology

Recent advances in transition metal chalcogenides for lithium-ion capacitors

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Rare Metals 2022年第9期41卷 2971-2984页

作者： Lei Wang Xiong Zhang Chen Li Xian-Zhong Sun Kai Wang Fang-Yuan Su Fang-Yan Liu Yan-Wei Ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing100190China School of Engineering sciences University of Chinese Academy of SciencesBeijing100049China Institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan250013China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian116023China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan030001China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

Transition metal chalcogenides(TMCs)and TMCs-based nanocomposites have attracted extensive attention due to their versatile material species,low cost,and rich physical and chemical *** anode materials of lithium-ion capacitors(LICs),TMCs have exhibited high theoretical capacities and pseudocapacitance storage ***,there are many intrinsic challenges,such as low electrical conductivity,repeatedly high-volume changes and sluggish ionic diffusion ***,many traditional and unconventional techniques have been reported to solve these critical problems,and many innovative strategies are also used to prepare high quality anode materials for *** this mini review,a detailed family member list and comparison of TMCs in the field of lithium-ion capacitors have been summarized ***,many rectification stratagems and recent researches of TMCs have been exhibited and *** the end,as an outcome of these discussions,some further challenges and perspectives are envisioned to promote the application of TMCs materials for lithium-ion c apacitors.

关键词： Energy storage Transition metal chalcogenides(TMCs) Lithium-ion capacitors(LICs) Performance optimization

Dynamic Stiffness nalysis and Experimental Verific tion of Axial Magnetic Bearing Based on Air Gap Flux Variation in Magnetically Suspended Molecular Pump

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Chinese Journal of Mechanical Engineering 2020年第4期33卷 147-157页

作者： Jinji Sun Wanting Wei Jiqiang Tang Chun-E Wang Key Laboratory of Fundamental science for National Defense Novel Inertial Instrument and Navigation System Technology School of Instrument Science and Opto-Electronics Engineering Beihang University State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Beijing Institute of Automatic Control Equipment

Current and displacement stiffness are important parameters of axial magnetic bearing(AMB) and are usually con-sidered as constants for the control system. However, in actual dynamic work situations, time-varying force leads to time-varying currents and air gap with a specific frequency, which makes the stiffness of appear decrease and even worsens control performance for the whole system. In this paper, an AMB dynamic stiffness model considering the flux variation across the air gap due to frequency is established to obtain the accurate dynamic stiffness. The dynamic stiffness characteristics are analyzed by means of the dynamic equivalent magnetic circuit method. The analytical results show that the amplitude of current and displacement stiffness decreases with frequency increasing. Moreover, compared with the stiffness model without considering the variation of flux density across the air gap, the improved dynamic stiffness results are closer to the actual results. Through the dynamic stiffness measurement method of AMB, experiments of AMB in magnetically suspended molecular pump(MSMP) are carried out and the experimental results are consistent with theoretical analysis results. This paper proposes the dynamic stiffness model of axial magnetic bearing considering the variation of flux density across the air gap, which improves the accuracy of the AMB stiffness analysis.

关键词： Axial magnetic bearing (AMB) Dynamic stiffness Magnetically suspended molecular pump (MSMP)

Current understanding of osteoarthritis pathogenesis and relevant new approaches

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Bone Research 2022年第4期10卷 627-643页

作者： Liping Tong Huan Yu Xingyun Huang Jie Shen Guozhi Xiao Lin Chen Huaiyu Wang Lianping Xing Di Chen Research Center for Computer-aided Drug Discovery Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518005China Faculty of Pharmaceutical sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Orthopedic Surgery School of MedicineWashington University in St.LouisSt.LouisMO 63110USA School of Medicine Southern University of Science and TechnologyShenzhen 518055China Department of Wound Repair and Rehabilitation State Key Laboratory of TraumaBurns and Combined InjuryDaping HospitalArmy Medical UniversityChongqing 400042China Research Center for Human Tissues and Organs Degeneration Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Pathology and Laboratory of Medicine Center for Musculoskeletal ResearchUniversity of Rochester Medical CenterRochesterNY 14642USA

Osteoarthritis(OA)is the most common degenerative joint disease that causes painful swelling and permanent damage to the joints in the *** molecular mechanisms of OA are currently *** is a heterogeneous disease that affects the entire joint,and multiple tissues are altered during OA *** better understand the pathological mechanisms of OA,new approaches,methods,and techniques need to be used to understand OA *** this review,we first focus on the epigenetic regulation of OA,with a particular focus on DNA methylation,histone modification,and microRNA regulation,followed by a summary of several key mediators in OA-associated *** then introduce several innovative techniques that have been and will continue to be used in the fields of OA and OA-associated pain,such as CRISPR,scRNA sequencing,and lineage ***,we discuss the timely updates concerning cell death regulation in OA pathology,including pyroptosis,ferroptosis,and autophagy,as well as their individual roles in OA and potential molecular targets in treating ***,our review highlights new directions on the role of the synovial lymphatic system in *** improved understanding of OA pathogenesis will aid in the development of more specific and effective therapeutic interventions for OA.

关键词： pathogenesis swelling concerning

深埋TBM隧洞岩爆事件微震释放能及等级认定——以Neelum-Jhelum水电工程为例

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Journal of Central South University 2023年第5期30卷 1695-1709页

作者：丰光亮马金刚陈炳瑞肖亚勋江权李鹏翔吝曼卿 State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Resources and Safety Engineering Wuhan Institute of TechnologyWuhan 430073China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines(Northeastern University) Shenyang 110819China

深埋全断面隧道掘进机(TBM)开挖诱发的岩爆灾害严重危害施工安全,开展TBM隧洞岩爆研究具有重要意义。基于巴基斯坦Neelum-Jhelum水电站深埋TBM隧洞的43个岩爆案例及原位微震实时监测信息,对TBM隧洞岩爆事件发生时刻的微震释放能及岩爆... 详细信息

深埋全断面隧道掘进机(TBM)开挖诱发的岩爆灾害严重危害施工安全,开展TBM隧洞岩爆研究具有重要意义。基于巴基斯坦Neelum-Jhelum水电站深埋TBM隧洞的43个岩爆案例及原位微震实时监测信息,对TBM隧洞岩爆事件发生时刻的微震释放能及岩爆等级认定标准进行了研究。采用距离判别法对岩爆事件进行预处理以扩充岩爆案例,研究了不同等级不同岩性条件下TBM隧洞岩爆事件的微震释放能特征。利用微震释放能定量参数,建立了不同条件下微震释放能TBM隧洞岩爆等级的认定标准。岩爆等级越高,微震释放能的定量阈值越大,两者呈现非线性关系;相同等级岩爆,砂岩的阈值要高于粉砂岩。因此,在对岩爆事件的等级进行认定时,有必要区分岩性。基于工程实例对所建立的认定标准进行验证分析,证明所建立的认定标准可用可靠。该研究成果可为深埋TBM隧洞岩爆认知和预警提供依据。

关键词：隧洞全断面隧道掘进机岩爆等级微震释放能 Neelum-Jhelum水电站