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Hybrid-panel-based new design idea for large reflector antenna

Science China(Technological Sciences) 2023年第1期66卷 115-126页

作者： LIAN PeiYuan YAN YueFei WANG CongSi QIN Long xue song WANG Na XU Qian ZHAO WuLin ZHENG YuanPeng School of Mechano-Electronic Engineering Xidian UniversityXi'an 710071China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300llChina China Electronics Technology Group Corporation No.39 Research Institute Xi'an 710065China China Electronics Technology Group Corporation No.54 Research Institute Shijiazhuang 050081China

Large reflector antennas are widely used as radio telescopes and active main reflectors are generally applied to improve the surface accuracy. Considering that the high cost has been one important problem in engineering, it is worth discussing whether it is necessary to install actuators on all the panels. Thus, in this paper, a hybrid-panel-based new design idea for large reflector antenna is proposed. Assuming that the actuators are installed only in the region of the reflector with large deformations and there are no actuators in other region to reduce the actuator number, the surface accuracies and the corresponding electromagnetic(EM) performances calculated by three different panel adjustment strategies are compared. The most effective method is that the deformed reflector should be first preadjusted to reduce the gravity deformation and then the panels equipped with actuators should be adjusted to the locations determined by the best fitting reflector(BFR) derived by the deformed reflector with no actuators. A 35 m reflector antenna is adopted as an example to calculate the surface accuracy and EM performance when parts of the panels are equipped with actuators. The simulation results show that there is no need to install actuators on all panels and the presented method can greatly reduce the number of actuators with guaranteed surface accuracy. Thus, during the antenna structural design phase, once the surface accuracy requirement is given, the number of actuators can be minimized to reduce the manufacturing and maintenance costs as much as possible. This paper can provide valuable guidance for the design of an active main reflector with hybrid panels.

关键词： reflector antenna hybrid panel actuator distribution adjustment strategy surface accuracy power pattern

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Characteristics, preservation mechanisms, and significance of aragonite in lacustrine shale: A case study from the Jiyang Depression,Bohai Bay Basin

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Petroleum Science 2024年第5期21卷 3001-3015页

作者： Zhou-Hai Xiong Ying-Chang Cao song xue Guan-Min Wang Chao Liang Ke-Yu Liu School of Earth Science and Engineering Xi'an Shiyou University State Key Laboratory of Deep Oil and Gas China University of Petroleum(East China) Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Exploration and Development Research Institute Jilin Oilfield Company PetroChina

Aragonite is a metastable mineral, which is easily transformed into calcite, and generally difficult to preserve in the stratum. However, large amounts of aragonites were found in the Paleogene shale of the Jiyang Depression. The characteristics and preservation mechanisms of these aragonites were analyzed through a series of analytical methods, including cathodoluminescence, field-emission scanning electron microscopy(FESEM), laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS), microarea carbon and oxygen isotopes, Sr isotopes, and dissolution simulation experiments under high temperature and high pressure. The research results show that:(1)Aragonite in the Paleogene shale of the Jiyang Depression is related to algal microbial fossils, primarily composed of coccoliths and characterized by two emission peaks at 420 nm and 480 nm in cathodoluminescence;(2)The primary factor allowing biological aragonite to be preserved is the immaturity of the organic matter and the deficiency of abundant organic acids necessary for its dissolution or transformation, which is confirmed by the evidence of organic matter maturity and simulation experiments of organic acid dissolution on aragonite under high-temperature and high-pressure conditions. Additional factors that may aid in the preservation of aragonite are the ideal sedimentation conditions, the defense of organic coating, and the enclosed environment with tiny pores, low porosity, and low permeability;(3)These aragonite-rich shales, characterized by coccolithophores, provide a solid evidence for seawater intrusion into terrestrial lake basin, and have a significant implication for the source and storage of shale oil.

关键词： Fine-grained sedimentary rocks Shale oil Aragonite Sedimentation Diagenesis

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Effect of Interchain Coupling on Quantum Lattice Fluctuation and Fluctuation Induced Interchain Order Transition in Trans-polyacetylene

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Chinese Physics Letters 1997年第9期14卷 694-697页

作者： ZENG Shang-you RAO xue-song WU Chang-qin SUN xin Department of Physics Fudan UniversityShanghai 200433

Based on the modified Su-Schrieffer-Heeger Harniltonian and by adding the interchain hopping term,we consider the effect of interchain coupling on quantum lattice fluctuation in *** has been found that the interchain coupling does not always weaken quantum lattice *** overcoming a barrier of 1 eV or so,the quantum lattice fluctuation can induce a transition of interchain *** physical meaning of these features is discussed.

关键词： order. quantum lattice

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Zero-Point Motions in Trans-Polyacetylene

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Chinese Physics Letters 1998年第9期15卷 674-676页

作者： FU Rong-tang RAO xue-song SUN Xin Y.Kawazoe Department of Physics Fudan UniversityShanghai 2004331 Institute for Materials Research Tohoku UniversitySendai 980-77Japan

In order to substantiate the applicability of the Takayama-Lin-Liu-Maki model to conducting polymer,the Su-Schrieffer-Heeger model is generalized to include the effects of lattice zero-point motions on electronic *** the treatment of the white-noise approximation,some significant electronic properties of Peierls-Fröhlich states are *** finding shows that the correlation of lattice motions suppresses the effects of zero-point motions on the electronic properties more seriously.

关键词： properties lattice electronic

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Vacuum joints of dispersion-strengthened copper and its applications in synchrotron radiation front end

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Nuclear Science and Techniques 2016年第6期27卷 74-78页

作者： Yong-Jun Li song xue Min Zhang Dan-Dan Jia Dong-Bai Dou Yu Gao Shanghai Institute of Applied Physics Chinese Academy ofSciencesZhangJiangShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China SKY Technology Development Co. LtdChinese Academyof SciencesShenyang 110179China

Masks are critical elements of synchrotron radiation front end that are exposed to high temperature and *** absorber material is typically comprised of dispersion-strengthened copper,which can retain high performance at elevated *** processes under vacuum,including brazing and electron beam welding,are novel approaches for prolonging the absorber and for reducing power *** mechanical properties of brazed joints and electron beam welded joints of dispersion-strengthened copper workpieces are evaluated by tensile testing at 20,100,and 200 *** testing results indicate that the tensile strength and elongation of both vacuum joints decrease with increasing *** to brazed joints,electron beam welded joints have higher tensile strength,better ductility,and more stable performance.A novel welded mask with a total length of 600 mm is presented and shown to be practical for use in the highest heat load front end in the Shanghai synchrotron radiation facility phase-Ⅱ beamline project.

关键词：上海同步辐射装置弥散强化铜焊接接头前端真空电子束焊接应用钎焊接头

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New Terms for Compact Form of Electroweak Chiral Lagrangian

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Communications in Theoretical Physics 2008年第3期49卷 723-724页

作者： ZHANG Hong-Hao YAN Wen-Bin J.K. Parry LI xue-song School of Physics and Engineering Sun Yet-Sen University Gunagzhou 510275 China Center for High Energy Physics ＆ Department of Physics Tsinghua University Beijing 100084 China Science College Hunan Agricultural University Changsha 410128 China Department of Physics and Astronomy State University of New York at Stony Brook New York 11794 USA

The compact form of the electroweak chiral Lagrangian is a reformulation of its original form and is expressed in terms of chiral rotated electroweak gauge fields, which is crucial for relating the information of underlying theories to the coefficients of the low-energy effective Lagrangian. However the compact form obtained in previous works is not complete. In this letter we add several new chiral invariant terms to it and discuss the contributions of these terms to the original electroweak chiral Lagrangian.

关键词： electroweak chiral Lagrangian beyond standard model

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Predicting Critical Conditions and Stress-Strain Curves for Dynamic Recrystallization in SPHC Steel

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Journal of Iron and Steel Research International 2010年第7期17卷 51-57页

作者： WU Lai-zhi LI xue-song CHEN Jun ZHANG Hong-bing CUI Zhen-shan Department of Plasticity Technology Shanghai Jiaotong University Shanghai 200030 China

The hot compression tests on an SPHC steel were carried out in the temperature range of 900-1150 ℃ and strain rate range of 0.1-10 s-1,in which the maximum true strain is *** activation energy of test steel was calculated,to be 299.4 kJ/*** critical stresses and strains for initiation of dynamic recrystallization were determined based on changes of the work hardening rate（θ）as a function of the flow stress（σ）or strain（ε）,*** dependence of the peak strain（εp）,the peak stress（σp）,and the steady state stress（σs）were determined based on the Zener-Hollomen *** mathematical models of the flow stress evolution were established in the hardening and dynamic recovery region and dynamic recrystallization region,*** average error between experimental curves and predicted ones was around 3.26%.

关键词： flow stress dynamic recrystallization critical stress critical strain SPHC steel

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A method of determining nonlinear large strain consolidation parameters of dredged clays

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Water Science and Engineering 2014年第2期7卷 218-226页

作者： Yu-peng CAO xue-song Wang Long DU Jian-wen Ding Yong-feng DENG Institute of Geotechnical Engineering Southeast University Municipal Facilities Authority Weifang Economic Development Zone

A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. （2010）, a relationship between the void ratio （e） and effective stress （a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient （k） and the ratio （e/eL） of the void ratio to the void ratio at the liquid limit （eL） is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. （1994）. Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g（e） defined by Gibson et al. （1981） and k/（1 ＋e） in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/（1 ＋e） increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.

关键词： initial void ratio permeability large strain consolidation parameter remolded yieldstress dredged clay

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Nickel trafficking system responsible for urease maturation inHelicobacter pylori

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World Journal of Gastroenterology 2013年第45期19卷 8211-8218页

作者： Rui-Guang Ge Dong-Xian Wang Ming-Cong Hao xue-song Sun Key Laboratory of Gene Engineering of the Ministry of Education and State Key Laboratory of Biocontrol College of Life Sciences Sun Yatsen University Laboratory of Proteomics the First Affiliated Hospital Sun Yat-sen University Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes Institute of Life and Health Engineering College of Life Science and Technology Jinan University

Helicobacter pylori(***)is a common human pathogen responsible for various gastric *** bacterium relies on the production of urease and hydrogenase to inhabit the acidic environment of the *** is an essential cofactor for urease and *** has to uptake sufficient nickel ions for the maturation of urease,and on the other way,to prevent the toxic effects of excessive nickel ***,*** has to strike a delicate balance between the import of nickel ions,its efficient intracellular storage,and delivery to nickel-dependent metalloenzymes when *** assembly and maturation of the urease enzyme is a complex and timely ordered process,requiring various regulatory,uptake,chaperone and accessory *** this review,we focus on several nickel trafficking proteins involved in urease maturation:NikR,NixA,HypAB,UreEFGH,HspA,Hpn and *** work will deepen our understanding of how this pathogenic bacterium adapts to severe habitant environments in the host.

关键词： Urease Histidine-rich protein NikR NixA Helicobacter pylori

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Molecular studies of the Medicago truncatula MtAnn3 gene involved in root hair deformation

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Chinese Science Bulletin 2012年第15期57卷 1803-1809页

作者： GONG ZiYing song xue CHEN GongYou ZHU JiaBi YU GuanQiao ZOU Huasong National Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological ScienceChinese Academy of SciencesShanghai 200032China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

The full-length annexin gene,MtAnn3,of Medicago truncatula was cloned by 5' *** with typical annexins,which contain a head domain and four homologous repeats in the conserved core domain,the MtAnn3 protein has only one repeat in the core ***3 can bind cell membranes when transiently expressed in onion epidermal *** rhizogenes-mediated transformation of MtAnn3 into Medicago roots revealed that overexpression of the gene can change the polarity of root hair growth in Ca2+-free *** plant hormone cytokinin was able to upregulate the expression of *** MtAnn3 transcripts were detected in young nodules,expression was not nodule-specific,and could be detected at high levels in the roots,stems and leaves as well.

关键词：蛋白基因苜蓿根分子生物学变形根毛膜联蛋白农杆菌介导细胞分裂素

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