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Chinese Journal of Structural Chemistry 2006年第11期25卷 1369-1374页

作者： wang qing-Wei LI Xiu-Mei HAN Jing College of Chemistry. dilin Normal University Siping 136000 China Department of Chemistry. Tonghua Teachers College Tonghua 134002 China College of Chemistry Jilin University Changchun 130023 China

A novel metal-organic coordination polymer {[Co2（4-sphth）2（4,4＇-bpyh（H2O）4]- [Co（4,4＇-bpy）2（H2O）4]}, （4-sphth = 4-sulfophthalic acid, 4,4＇-bpy = 4,4＇-bipyridine） 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and magnetic susceptibility measurements. The complex crystallizes in monoclinic, space group C2/c with a = 18.893（6）, b = 23.080（7）, c = 22.473（7） A, fl = 107.311 （4）°, V = 9356（5） A^3, C76H70Co3N12O22S2, Mr = 1744.35, De = 1.238 g/cm^3,μ（MoKα） = 0.640 mm^-1, F（000） = 3596, Z = 4, the final R = 0.0444 and wR = 0.0846 for 9178 observed reflections （I 〉 2σ（I））. It exhibits a novel three-dimensional supramolecular network formed by hydrogen-bonding and π-π interactions. Variable-temperature magnetic measure shows an overall anti-ferromagnetic behavior for compound 1.

关键词： hydrothermal synthesis supramolecular network magnetic properties

Effects of model size and particle size on the response of sea-ice samples created with a hexagonal-close-packing pattern in discrete-element method simulations

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Particuology 2018年第1期16卷 106-113页

作者： Shaocheng Di Yanzhuo Xue Xiaolong Bai qing wang College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

We investigated the effects of model size and particle size on the simulated macroscopic mechanical properties, uniaxial compressive strength, Young＇s modulus, and flexural strength of sea-ice samples, using the discrete-element method （DEM） with a bonded-particle model. Many different samples with a hexagonal-close-packing pattern and a unique particle size were considered, and several ratios of particle size to sample dimension （D/L） were studied for each sample. The macroscopic mechanical properties simulated by the DEM decrease monotonously with an increase in D/L. For different samples with different particle sizes, the macroscopic mechanical properties will be identical when D/L is constant. The quanti- tative relationships between macroscopic mechanical properties and ratio of particle size to sample size are important aspects in engineering applications of the DEM method. The results provide guidance on the choice of a particle size in the DEM simulation for numerical samples with a hexagonal-close-packing pattern.

关键词： Discrete-element method Bonded-particle model Sample size Particle size Size effect

Reconstruction of symmetric models composed of analytic curves and surfaces from point cloud

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1351-1362页

作者： qing wang Wei-dong ZHU Ying-lin KE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

This paper presents a method to reconstruct symmetric geometric models from point cloud with inherent symmetric structure. Symmetry types commonly found in engineering parts, i.e., translational, reflectional and rotational symmetries are considered. The reconstruction problem is formulated as a constrained optimization, where the objective function is the sum of squared distances of points to the model, and constraints are enforced to keep geometric relationships in the model. First, the explicit representations of symmetric models are presented. Then, by using the concept of parameterized points (where the coor-dinate components are represented as functions rather than constants), the distances of points to symmetric models are deduced. With these distance functions, symmetry information, for both 2D and 3D models, is uniformly represented in the process of reconstruction. The constrained optimization problem is solved by a standard nonlinear optimization method. Owing to the explicit representation of symmetry information, the computational complexity of our method is reduced greatly. Finally, examples are given to demonstrate the application of the proposed method.

关键词： Reverse engineering Model reconstruction Constrained optimization Symmetry

Adhesion and peeling of a Fugu coal molecule on a graphene substrate: molecular dynamics simulations

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Science China(Physics,Mechanics & Astronomy) 2020年第9期63卷 58-65页

作者： Peng Hao Ya Lin Luan qing wang JianLin Liu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China

Controlling coal dust produced in the process of underground coal mining is imperative because it can cause serious health problems,such as *** the present work,we have conducted a comprehensive investigation of the adhesion and peeling process of a coal molecule on graphene using molecular dynamics(MD)***,we simulate the adhesion of a coal molecule on a graphene substrate,where the critical adhesion distance and adhesion force are ***,the process of a coal molecule peeled from the substrate is simulated,the equilibrium configurations,loading position,peeling force,and peeling angle of which are *** comparing the MD simulation results with those of continuum models,we conclude that they are in excellent *** analyses have deepened our understanding of the interplay between coal molecules and solid surfaces,which may prove beneficial when creating scientific methods of dust control.

关键词： coal molecule adhesion peeling force peeling angle molecular dynamics

Inappropriate secretion of antidiuretic hormone:a rare complication after common bile duct exploration

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Hepatobiliary & Pancreatic Diseases International 2009年第5期8卷 544-546页

作者： Ruan, Yu Zhang, Wei wang, qing-qing Zhejiang Univ Sch Med Dept Endocrinol Sri Run Run Shaw Hosp Hangzhou 310016 Zhejiang Peoples R China Zhejiang Univ Sir Run Run Shaw Inst Clin Med Hangzhou 310016 Zhejiang Peoples R China Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Surg Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) as a dilutional hyponatremia is due to a pathological increase of antidiuretic hormone (ADH). It is characterized by hyponatremia and decreased serum osmolarity as well as an increase in urinary osmolarity. The most common etiological factors of this syndrome include diseases or trauma of the central nervous system and malignant tumor or inflammation of the lung. SIADH following abdominal surgery is rare. METHODS: We report the case of a 68-year-old woman who developed, 24 hours after common bile duct exploration and stone removal, continuous hyponatremia for 20 days and clinical manifestations of nausea, vomiting, and lethargy without focal neurological signs. RESULT: Laboratory examinations supported the diagnosis of SIADH. After therapy with fluid restriction, the patient recovered. CONCLUSION: There are diverse causes for SIADH. It is important to have kept this clinical possibility in mind in the differential diagnosis of refractory hyponatremia under any circumstances.

关键词： inappropriate antidiuretic hormone syndrome surgery hyponatremia

Switched adaptive active disturbance rejection control of variable structure near space vehicles based on adaptive dynamic programming

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Chinese Journal of Aeronautics 2019年第7期32卷 1684-1694页

作者： Chaoyang DONG Chen LIU qing wang Ligang GONG School of Aeronautic Science and Engineering Beihang UniversityBeijing100083China Beijing Institute of Electric System Engineering Beijing100854China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100083China

Based on the switched nonlinear system, a switched adaptive Active Disturbance Rejection Control(ADRC) law is proposed for the Variable Structure Near Space Vehicle(VSNSV) with unknown uncertainties and external disturbances. The reduced-order Extended State Observers(ESOs) are constructed for the attitude angle system and the angular rate system to estimate the total disturbance in real time. With the extended state introduced to counteract the effects of uncertainties and disturbances, a systematic procedure is presented for the synthesis of the switched adaptive ADRC strategy. Rigorous proof shows that the estimation errors of the reduced-order ESOs would converge to a small neighborhood of zero in finite time, and that the output of the closedloop system can track a given signal stably for a class of switching signals with average dwell time via the proposed approach. The variable gain control strategy based on Adaptive Dynamic Programming(ADP) with the actor-critic structure is also designed to improve the dynamic performance of the system. Simulation results verify the effectiveness and advantage of the proposed control scheme.

关键词： Adaptive control ADP ADRC Attitude control Switched nonlinear system VSNSV

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： Chao-Yue Sun Wen Li Hai-qing wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

Electronic transport and magnetic performance of Ni-Nb-Zr metallic glasses

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Rare Metals 2017年第11期36卷 894-898页

作者： Hai-Bin wang qing wang Chong-Lin Chen Chuang Dong School of Materials Science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Department of Physics and Astronomy University of Texas at San Antonio San Antonio TX 78249 USA

The electronic transport and magnetic perfor- mances of Ni-Nb-Zr metallic glasses under low temperature were investigated. X-ray diffraction （XRD） analysis indicates that the Ni-Nb-Zr ribbons prepared by induction melting and melt spinning method have single amorphous phase. The electrical transport property results of these metallic glass alloys indicate that the Ni-Nb-Zr metallic glasses have negative resistivity temperature coefficients （RTC） and low- temperature drift. The negative RTC and corresponding pos- sible values of Fermi energy of Ni-Nb-Zr metallic glasses are interpreted by the extended Ziman-Faber diffraction theory. The magnetic measurements indicate that the magnetic in- tensities of the Ni-Nb-Zr metallic glasses are related to Ni content and atomic sizes while the low temperature has few influences on the magnetic properties.

关键词： Metallic glass Electrical resistance Magneticproperties

Transgenic Brassica chinensis plants expressing a bacterial codA gene exhibit enhanced tolerance to extreme temperature and high salinity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第11期11卷 851-861页

作者： qing-bin wang Wen XU qing-zhong XUE Wei-ai SU Department of Agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Shanghai Institute of Plant Physiology and Ecology Chinese Academy of Science Shanghai 200032 China School of Resource and Environment Management Guizhou College of Finance and Economics Guiyang 550004 China

Transgenic Brassica compestris *** plants expressing a choline oxidase(codA) gene from Arthrobacter globiformis were obtained through Agrobacterium tumefaciens-mediated *** the transgenic plants,codA gene expression and its product transportation to chloroplasts were detected by the enzyme-linked immunosorbent assay(ELISA) examination,immunogold localization,and 1 H-nuclear magnetic resonance( 1 H-NMR) . Stress tolerance was evaluated in the T3 plants under extreme temperature and salinity *** plants of transgenic line 1(L1) showed significantly higher net photosynthetic rate(Pn) and Pn recovery rate under high(45°C,4 h) and low temperature(1°C,48 h) treatments,and higher photosynthetic rate under high salinity conditions(100,200,and 300 mmol/L NaCl,respectively) than the wild-type *** enhanced tolerance to high temperature and high salinity stresses in transgenic plants is associated with the accumulation of betaine,which is not found in the wild-type *** results indicate that the introduction of codA gene from Arthrobacter globiformis into Brassica compestris *** could be a potential strategy for improving the plant tolerance to multiple stresses.

关键词： Brassica compestris L. spp. chinensis codA Stress Glycine betaine Net photosynthetic rate (Pn)

Deformation measurement by single spherical near-field intensity measurement for large reflector antenna

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Research in Astronomy and Astrophysics 2021年第10期21卷 175-186页

作者： Qian Ye Bo-Yang wang Qiang Yao Jin-qing wang qing-Hui Liu Zhi-Qiang Shen Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Mechanical Engineering Shanghai Jiao Tong UnversityShanghai 200240China

This paper presents a new method to obtain the deformation distribution on the main reflector of an antenna only by measuring the electric intensity on a spherical surface with the focal point as the center of the sphere,regardless of *** the differential geometry theory with geometric optics method,this paper has derived a deformation-intensity equation to relate the surface deformation to the intensity distribution of a spherical near-field *** on the finite difference method(FDM)and GaussSeidel iteration,deformation has been calculated from intensity simulated by geometrical optics(GO)and physical optics(PO)methods,respectively,with relatively small errors,which prove the effectiveness of the equation proposed in this *** means of this method,it is possible to measure the deformation only by scanning the electric intensity of a single hemispherical near-field whose area is only about 1/15 of the *** measurement only needs a plane wave at any frequency as the incident wave,which means that both the signals from the outer space satellite and the far-field artificial beacon could be used as the *** scanning can be realized no matter what attitude and elevation angle the antenna is in because the size and angle of the hemisphere are changeable.

关键词： telescopes waves line:profiles scattering