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中国有色金属学会会刊：英文版 2000年第S1期10卷 12-18页

作者： R. Du Plessis 1, J.D. Miller 1, J.C.Davidtz 2.1. department of Metallurgical Engineering, university of Utah, Salt Lake {2., Utah 84102. USA 2. department of Materials Science and Metallurgical Engineering, university of Pretoria, Pretoria 0002 Univ Utah Dept Met Engn Salt Lake City UT 84102 USA Univ Pretoria Dept Met Engn & Mat Sci ZA-0002 Pretoria South Africa

The redox potentials of xanthate/dixanthogen (dithiocarbonate/di dithiocarbonate, DTC/(DTC) 2. and trithiocarbonate/di trithiocarbonate (TTC/(TTC) 2. couples have been measured for the potassium salts. The spectroscopic characteristics of these sulfide mineral collectors were determined by FTIR and UV analysis. Electrochemically controlled contact angle measurements at a pyrite surface provided the basis to analyze the effect of the functional group ( O CS 2.versus S CS 2. on the hydrophobic surface state. Results from this preliminary examination are discussed with respect to the nature of collector adsorption and the pyrite flotation response.

关键词： redox potential trithiocarbonate collector sulfide mineral flotation

Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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Science China Chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2.& MO Tian2.1. college of Chemistry and Molecular Engineering, Peking university, Beijing 100871, China 2. {2. of Chemistry, Hong Kong Baptist university, Hong Kong, China 1. college of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. department of Chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2.), Cd^(2.), Pb^(2.), Cu^(2.), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

Antisense Oligodeoxynucleotide Inhibits Expression of Re-com binantPorcine Follicle-Stim ulating Horm one Receptor

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Journal of Huazhong university of Science and Technology(Medical Sciences) 1999年第3期19卷 175-180页

作者： ZHU Changhong 1, Mark D. Nixon 2. WANG Yifang 1, Andrew R. LaBarbera 3 1 Center of Reproductive medicine, Tongji Hospital, Tongji Medical university, Wuhan 430030 2.{2. of Obstetrics and Gynecology, university of Cincinnati college of medicine, Cincinnati, Ohio 452.7 052. 3 {2. of Molecular and Cellular Physiology, university of Cincinnati college of medicine, Cincinnati, Ohio 452.7 052. Center of Reproductive medicine Tongji Hospital Tongji Medical University Wuhan 430030

To assess the role of follicle stimulating hormone receptor(FSHR) gene expression in regulating expression of FSHR protein in the plasma membrane, the effects of a porcine FSHR cDNA antisense oligodeoxynucleotide (ODN) on FSHR mRNA levels and 12. I FSH binding were determined in Chinese hamster ovary cells expression recombinant porcine FSHR (pFSHR CHO cells). An 18 mer phosphorothioate endcapped antisense ODN that corresponded to the region surrounding the translation initiation codon of the porcine FSHR cDNA was synthesized. An 18 mer nonsense sequence of identical nucleotide composition, which had little homology to known DNA sequences, was synthesized for use as a control. pFSHR CHO cells were cultured in 2. well plates (10 5 cells/well) in the absence or presence of 1 2. μmol/L antisense or nonsense ODN for 2. h and then assayed for porcine FSHR mRNA, using quantitative reverse transcription and competitive polymerase chain reaction, and for 12. I FSH binding activity. Treatment with 10 μmol/L antisense ODN caused a paradoxical increase in porcine FSHR mRNA from 0.89±0.06 to 1.64±0.08 ng/mg total RNA ( P 2. I FSH by 13.6± 0.8 % ( P 2. h. Treatment of cells with antisense ODN (10 μmol/L) for 48 h resulted in a 76±1.5 % ( P 2. I FSH binding. In contrast, transfection with lipofectamine and 0.33 μmol/L antisense ODN at 0 h caused a 76.1±1.3 % ( P 2. h. Binding had returned to 52.3±2.3 % ( P < 0.05) of normal by 48 h. These results indicate

关键词： follicle stimulating hormone antisense oligodeoxynucleotide folliculogenesis mRNA spermatogenesis

The refined theory of deep rectangular beams based on general solutions of elasticity

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Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. college of Science, China Agricultural university, Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and {2. of Mechanics and Engi- neering Science, Peking university, Beijing 100871, China college of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems department of Mechanics Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

Structure and function of aggrecan

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Cell Research 2002年第1期12卷 19-32页

作者： CHRIS KiaNI, LIWEN CHEN, YAO JIONG WU, ALBERT J YEE, BURTON B YANG, Sunnybrook and Women’s college Health Sciences Centre and department of Laboratory {2. and Patobiology, 2.department of Surgeny, Faculty of {2., university of Toronto, Canada 1Sunnybrook and Women s college Health Sciences Centre and department of Laboratory {2. and Pathobiology University of Toronto Canada 1Sunnybrook and Women s college Health Sciences Centre and department of Laboratory {2. and Pathobiology University of Toronto Canada 1Sunnybrook and Women s college Health Sciences Centre and department of Laboratory {2. and Pathobiology University of Toronto Canada 2.unnybrook and Women s college Health Sciences Centre and department of Surgeny Faculty of Medicine University of Toronto Canada 1Sunnybrook and Women s college Health Sciences Centre and department of Laboratory {2. and Pathobiology University of Toronto Canada

Aggrecan is the major proteoglycan in the articular cartilage. This molecule is important in the proper functioning of articular cartilage because it provides a hydrated gel structure (via its interaction with hyaluronan and link protein) that endows the cartilage with load-bearing properties. It is also crucial in chondroskeletal morphogenesis during development. Aggrecan is a multimodular molecule expressed by chondrocytes. Its core protein is composed of three globular domains (G1, G2. and G3) and a large extended region (CS) between G2.and G3 for glycosaminoglycan chain attachment. G1 comprises the amino terminus of the core protein. This domain has the same structural motif as link protein. Functionally, the G1 domain interacts with hyaluronan acid and link protein, forming stable ternary complexes in the extracellular matrix. G2.is homologous to the tandem repeats of G1 and of link protein and is involved in product processing. G3 makes up the carboxyl terminus of the core protein. It enhances glycosaminoglycan modification and product secretion. Aggrecan plays an important role in mediating chondrocyte-chondrocyte and chondrocyte-matrix interactions through its ability to bind hyaluronan.

关键词： Proteoglycan chondroitin sulfate glycosaminoglycan G1 domain G3 domain.

The refined theory of transversely isotropic piezoelectric rectangular beams

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. college of Science, China Agricultural university, Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and {2. of Mechanics and Engi- neering Science, Peking university, Beijing 100871, China 1. college of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

1.55 μm Wavelength Operation of E_r^(3+) -Doped Optical Fiber Bistability

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Wuhan university Journal of Natural Sciences 1999年第4期4卷 435-438页

作者： SONG Qian 1, ZHANG Yuan cheng 2.1. college of Electronics Information, Wuhan university, Wuhan 430072. China 2. {2. of Physics, Wuhan university, Wuhan 430072. China Wuhan university College of Electronics Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) Wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

An all optical all fiber optical bistability operation has been realized in an all fiber cavity consisted with Er doped fiber and optical fiber loop mirrors. The experimental bistability threshold is consistent w... 详细信息

关键词： optical nonlinearity optical bistability Er doped fiber all fiber device

Minimal symmetric submanifolds in compact Riemannian symmetric spaces

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Chinese Science Bulletin 1998年第21期43卷 1786-1789页

作者： LiaNG Ke 1 and JIN Quanqin 1,2.1. department of Mathematics, Nankai university, Tianjin 300071, China 2. department of Mathematics, Hebei university, Baoding 071002. China department of Mathematics Nankai University Tianjin China department of Mathematics Hebei University Baoding China

A necessary and sufficient condition for a symmetric submanifold to be minimal in its ambient compact Riemannian symmetric space is given. By this condition a complete classification of non- minimal symmetric submanif... 详细信息

关键词： symmetric space symmetric submanifold mean curvature vector.

Cartesian closedness of categories of completely distributive lattices

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Chinese Science Bulletin 1998年第24期43卷 2059-2063页

作者： ZHANG Dexue 1 and YANG Zhongqiang 2.1. department of Mathematics, Sichuan university, Chengdu 610064, China 2. department of Mathematics, Shaanxi Normal university, Xi’an 710062. China department of Mathematics Sichuan University Chengdu China department of Mathematics Shaanxi Normal University Xi’an China

The category of completely distributive lattices with Scott continuous functions is cartesian closed. Neither the category of completely distributive lattices with arbitrary union preserving mappings nor the category ... 详细信息

关键词： completely distributive lattice continuous lattice cartesian closedness.

A ROBUST DECOMPOSITION OF LINEAR PROGRAMMING USING A GOAL-PARTITIONING METHOD

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Systems Science and Mathematical Sciences 1991年第1期4卷 68-77页

作者：陶惠民朱纪善 department of Mathematics Tianjin Institute of TechnologyTianjin 300191China department of Management Sciences The University of IowaIowa cityU.S.A.

The Dantzig/Wolfe linear programming decomposition algorithm has had important economicinterpretations as well as a widespread impact on solving large scale linear programming *** paper we consider a similar underlying structure,where however there is only one couplinginequality or *** this simplification,we demonstrate how to achieve an equitable partitionof the overall coupling resource to individual subproblem constraints through a simple iterationprocedure which appears to be very efficient.

关键词： Linear programming decomposition principal optimal resource partition economic interpretation robust goals