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Study on the two and three-parameter working stability regions of 3Y-TZP suspension

Science China(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1. 2, ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. department of Chemistry,{1., qingdao 266071, China 2. department of Chemistry, Tsinghua university, Beijing 1.0084, China 3. department of physics,{1., qingdao 266071, China department of Chemistry Qingdao University Qingdao China department of Chemistry Tsinghua University Beijing China department of {1. Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

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Research on dual-stator winding multi-phase high-speed induction generator with rectifier load

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Science China(Technological Sciences) 2008年第6期51卷 683-692页

作者： WANG XiangHeng1.& WU XinZhen2 1.department of Electrical Engineering, Tsinghua {1., Beijing 1.0084, China 2 department of Electrical Engineering, qingdao university, qingdao 266071, China department of Electrical Engineering Tsinghua University Beijing China department of Electrical Engineering Qingdao University Qingdao China

Based on analysis and calculation of the relation between current harmonics and MMF harmonics in the dual-stator winding multi-phase high-speed induction gen-erator with a rectifier load, a new idea, which divides the generator system into two sub-systems to be analyzed individually, is presented. For the sub-system of the 1.-phase power winding with a rectifier load, the loop current method is used to establish network equation set in terms of the network graph theory. The numerical stability problem is solved by alternating use of fixed time-step and varied time-step, and the voltage and current with their fundamental components of the power winding are obtained. For the other sub-system of the induction generator with dual-stator winding and solid cage rotor, the electromagnetic field analysis method and the multi-variable optimization approach are combined to get the con-trol winding current and stator frequency. Calculated results well match experiment results, indicating that the new proposed method is of effectiveness and high ac-curacy.

关键词： dual-stator winding induction generator rectifier load MMF analysis loop current method finite element method optimization approach

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Virtualities of quark and gluon in QCD vacuum

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Science China(physics,Mechanics & Astronomy) 2008年第10期51卷 1439-1447页

作者： ZHOU LiJuan1. QIN SongMei2, WU Qing3 & MA WeiXing4 1.Collaboration Group of Hadron physics and Non-perturbative QCD Study, Guangxi {1. of Tech- nology, Liuzhou 545006, China 2 department of physics, Guangxi {1., Nanning 540003, China 3 department of physics, qingdao university, qingdao 266071, China 4 Institute of High Energy physics, Chinese Academy of Sciences, Beijing 1.0049, China Collaboration Group of Hadron physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou China department of {1. Guangxi University Nanning China department of {1. Qingdao University Qingdao China Institute of High Energy physics Chinese Academy of Sciences Beijing China

The non-local vacuum condensates of quantum chromodynamics (QCD) describe the distributions of quarks and gluons in the non-perturbative QCD vacuum state. Physically, this means that vacuum quarks and gluons have a nonzero mean-squared momentum in the vacuum, called virtuality. The quark virtuality is given by the ratio of the local quark-gluon mixed vacuum condensate to the quark local vacuum condensate. The gluon virtuality is expressed by gluon vacuum condensates and four-quark vacuum condensates. We study the two virtualities by solving Dyson-Schwinger Equations and calculating quark and gluon vacuum condensates. Our theoretical results for quark virtuality are in good agreement with many other theoretical model predictions such as QCD sum rules and lattice QCD calculations. Our calculation on gluon virtuality is initial and the results are quite interesting.

关键词： quark gluon virtuality QCD vacuum condensate non-perturbative QCD

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Analysis on cohesive crack opening displacement considering the strain softening effect

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Science China(physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1. XU Shilang2 & ZHAO Xiqiang3 1. Mechanics department, Shandong {1. of Technology, Zibo 255049, China 2. Civil Engineering department, Dalian {1. of Technology, Dalian 1.6024, China 3. Mathematics department, Ocean {1. of China, qingdao 266071, China Mechanics department Shandong University of Technology Zibo China Civil Engineering department Dalian University of Technology Dalian China Mathematics department Ocean University of China Qingdao China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

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Polypeptide from Chlamys farreri attenuates murine thymocytes damage induced by ultraviolet B

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Acta Pharmacologica Sinica 2007年第10期28卷 1665-1670页

作者： Hai-ying CHEN~(2,3),Xiao CHU~4,Chun-ling YAN~5,Xue-hong CHEN~5,Mi SUN~6,Yue-jun WANG~6,Chun-bo WANG~(3,7),Wen-gong YU~(2,7)~2 department of Pharmacochemistry,Ocean {1. of China,qingdao 266003,China ~3 department of Pharmacology,Medical College,qingdao{1.,qingdao 266021,China ~4 qingdao Municipal Hospital,qingdao 266010,China ~5 department of Pathophysiology,MedicalCollege,qingdao {1.,qingdao 266021,China ~6 Yellow Sea Fishery Research Institute,qingdao {1.},China department of Pharmacochemistry Ocean University of China Qingdao China department of Pharmacology Medical College Qingdao University Qingdao China qingdao Municipal Hospital Qingdao China department of Pathophysiology Medical College Qingdao University Qingdao China Yellow Sea Fishery Research Institute Qingdao China

Aim:Polypeptide from Chlamys farreri (PCF,molecular mass is 879) is a newmarine polypeptide compound isolated from Chlamys *** study investi-gates the possible protective roles and the mechanism of PCF against ultravioletB (UVB)-induced apoptosis in murine ***:The rate of apoptosisand caspase-3 activation was measured by flow *** expression ofstress-response genes c-fos and c-jun was observed by *** blotanalysis was performed to determine the release of cytochrome ***:It wasfound that UVB induced murine thymocyte *** cells treated with UVBshowed an increase in cytochrome c release,caspase-3 activity,as well as in theexpression of c-fos and *** addition,all were involved in UVB-induced ***:Our present observations pointed to the ability of PCF toavert UVB-induced apoptosis in thymocytes by modulating c-fos and c-junexpression,cytochrome c release,and the consequent activation of caspase-3,which were essential components of the UV-induced cell apoptotic *** suggested that PCF is a promising protective substance against UVradiation.

关键词： polypeptide from Chlamys farreri (PCF) ultraviolet B apoptosis cytochrome c caspase-3

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Symmetries and exact solutions of discrete nonconservative systems

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Science China(physics,Mechanics & Astronomy) 2010年第9期53卷 1699-1706页

作者： FU JingLi1.LI XiaoWei2,LI ChaoRong1.ZHAO WeiJia3 & CHEN BenYong4 1.Institute of Mathematical physics,Zhejiang Sci-Tech {1.,Hangzhou 31.01.,China 2 department of physics,Shangqiu Normal {1.,Shangqiu 476000,China 3 department of Mathematics,qingdao {1.,qingdao 266071,China 4 Faculty of Mechanical Engineering & Automation,Zhejiang Sci-Tech {1.,Hangzhou 31.01.,China Institute of Mathematical physics Zhejiang Sci-Tech University Hangzhou China department of {1. Shangqiu Normal University Shangqiu China department of Mathematics Qingdao University Qingdao China Faculty of Mechanical Engineering & Automation Zhejiang Sci-Tech University Hangzhou China

Based on the property of the discrete model entirely inheriting the symmetry of the continuous system,we present a method to construct exact solutions with continuous groups of transformations in discrete nonconservative *** Noether's identity of the discrete nonconservative system is *** symmetric discrete Lagrangian and symmetric discrete nonconservative forces are defined for the *** quasi-extremal equations of discrete nonconservative systems are *** conserved quantities are derived with symmetries associated with the continuous *** have also found that the existence of the one-parameter symmetry group provides a reduction to a conserved quantity;but the existence of a two-parameter symmetry group makes it possible to obtain an exact solution for a discrete nonconservative *** examples are discussed to illustrate these results.

关键词： discrete nonconservative system symmetry conserved quantity quasi-extremal equation exact solution

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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science China(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1.2, SUN Weiguo1. HOU Shilin3 & FENG Hao4 1. Institute of physics, College of Chemical Engineering, Sichuan {1., Chengdu 61.065, China 2. Institute of Theoretical physics, Xihua Normal {1., Nanchong 637002, China 3. department of physics, China Oceanography {1., qingdao 266003, China 4. College of physics, Sichuan {1., Chengdu 61.065, China Institute of physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical physics Xihua Normal University Nanchong China department of {1. China Oceanography University Qingdao China College of physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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Science China Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1.2,LIN XueHui1.2,YAO De3,4 & GUO WeiDong5 1.Key Laboratory of Marine Oil and Gas Resources and Marine Environment,Ministry of Land and Resources,qingdao {1.,China 2 qingdao Institute of Marine Geology,China Geological Survey,qingdao {1.,China 3 Institute of Resources and Environment,Shandong university of Technology,Zibo 255049,China 4 Institute of Oceanology,Chinese Academy of Sciences,qingdao {1.,China 5 department of Oceanography,Xiamen university,Xiamen 361.05,China Key Laboratory of Marine Oil and Gas Resources and Marine Environment Ministry of Land and Resources Qingdao China qingdao Institute of Marine Geology China Geological Survey Qingdao China Institute of Resources and Environment Shandong University of Technology Zibo China Institute of Oceanology Chinese Academy of Sciences Qingdao China department of Oceanography Xiamen University Xiamen China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

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Structure of a pair of anticyclonic vortices in northern part of the South China Sea in autumn of 1.94

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Acta Oceanologica Sinica 2002年第2期21卷 203-216页

作者： Fu Gang, Toshio Yamagata1. department of Marine Meteorology, Ocean {1. of qingdao, qingdao 266003, China2. department of Earth and Planetary physics, {1. of Tokyo, Japan department of Marine Meteorology Ocean University of Qingdao Qingdao 266003 China department of Earth and Planetary {1. University of Tokyo Japan

A pair of remarkable meso-scale anticyclonic vortices, one formed closely to another, inthe northern part of the South China Sea during the period from the later August to early September of 1.94 were documented by the in situ observation data. Their spatial structures were examined in detail from the horizontal and two nearly perpendicular/vertical angles of view. It was shown that the horizontal scales of these two vortices were around 1.0, 50 km, and their vertical scales were about 500, 1.00 m, respectively. Two 'warm core' structures associated with these two vortices were found in their horizontal and vertical analyses. The closer spacing of these two vortices (namely, 60 km), which was smaller than the Rossby radius of deformation, suggested that they might merge with each other during their next evolution stages and form into a larger vortex eventually.

关键词： The South China Sea a pair of anticyclonic vortices warm core Rossby radius of deforma-tion

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Preparation and Characterization of Bi_4Ti_3O_(1.) Platelets by a Novel Low-temperature Molten Salt System

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Journal of Wuhan university of Technology(Materials Science) 2009年第2期24卷 241-244页

作者：隋万美 College of physics Science Qingdao University

Bismuth titanate （Bi4Ti3O1.） platelets were prepared by molten salt method in a new salt system of CaCl2·NaCl at 650-750℃, using bismuth nitrate pentahydrate （Bi （NO3）3·H2O） and titanium butoxide （Ti （OC4H9）4） as raw materials. The synthesis temperature of Bi4Ti3O1. platelets was decreased to 650℃ from 900-1.00℃. The phase compositions and crystalline morphology of Bi4Ti3O1. platelets were investigated by XRD and SEM. The experimental results indicate that Bi4Ti3O1. platelets containing tetragonal and orthorhombic phase with the size of 1.3μm can be synthesized at 650℃ for 2 h, and the orthorhombic phase becomes the dominant phase at 750℃ for 5 h. The size and proportion of Bi4Ti3O1. platelets increase with the increment of the calcining temperature and holding time. The proportion of platelets increases to about ninety percent, and the platelets grow up to about 3-1.μm at 750℃ for 5 h from 1.2μm at 650℃ for 2 h. This technical route provides a new low-temperature molten salt system for preparing platelets by molten salt methods.

关键词： CaCl2-NaC1 molten salt Bi4Ti3O1. platelets

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