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A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2.F film optically transparent electrode

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Science china Chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2.& NIU Shuyan1,2.1. College of Chemistry and Molecular engineering, Qingdao {2. of Science and Technology, Qingdao 2.6042. china 2. College of Chemistry and Chemical engineering, ocean university of china, Qingdao 2.6003, china Correspondence should be addressed to Jiao Kui College of Chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao China College of Chemistry and Chemical engineering Ocean University of China Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2.F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. College of Civil engineering, Hunan {2., Changsha 410082. china 2. Department of Civil engineering, Tsinghua {2., Beijing 100084, china College of Civil engineering Hunan University Changsha China Department of Civil engineering Tsinghua University Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2.1. Department of Civil engineering,Shanghai university,Shanghai 2.0072.{2. 2. School of Transportation engineering,Tongji university,Shanghai 2.0092.{2. Department of Civil engineering Shanghai University Shanghai China School of Transportation engineering Tongji University Shanghai China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4 asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2. TAN Zhi-xiang1, 2. DENG Ka-zhong1, 2.1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 2.1116, china 2. Jiangsu Key Laboratory of Resources and Environmental Information engineering, china university of Mining and Technology, Xuzhou 2.1116, china Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of Resources and Environmental Information engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2.] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

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 university of Technology, Zibo 2.5049, china 2. Civil {2. Department, Dalian university of Technology, Dalian 11602., china 3. Mathematics Department, ocean university of china, Qingdao 2.6071, 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.

Analysis on the long term discharge of a catchment

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Journal of Environmental Sciences 2000年第3期12卷 279-285页

作者： HONG Lin 1, TAKASE Keiji 2. SATO Koichi 2.(1. Wuhan university of Hydraulic and Electric engineering, Wuhan 430072. {2. 2. Ehime university, Japan) Wuhan university of Hydraulic and Electric engineering Wuhan 430072 China Ehime university Japan

In this study, the characteristics of the long term discharge of a Terraced Paddy Field Catchment are studied. 2.Kind of Tank Models are proposed and used to simulate the discharge of the catchment. The characteristics of the model simulations of the discharge of the catchment are analyzed and compared with those of a forest catchment.

关键词： long term discharge model simulation terraced paddy field catchment

Chinese expert consensus on the clinical application of drugcoated balloon(2.(nd) Edition)

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Journal of Geriatric Cardiology 2024年第2期21卷 135-152页

作者： The Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon(2.(nd)Edition) Jun-Bo GE Yun-Dai CHEN 不详 Zhongshan Hospital Fudan University Chinese PLA General Hospital

Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and restenosis rates of target vessels and improved patient prognosis, making drug-eluting stents the mainstream interventional treatment for coronary artery disease. In recent years, drug-coated balloons(DCBs) have become a new treatment strategy for coronary artery disease, and the drugs used in the coating and the coating technology have progressed in the past years. Without permanent implant, a DCB delivers antiproliferative drugs rapidly and uniformly into the vessel wall via the excipient during a single balloon dilation. Many evidence suggests that DCB angioplasty is an effective measure for dealing with in-stent restenosis and de novo lesions in small coronary *** more clinical studies are published, new evidence is emerging for the use of DCB angioplasty in a wide range of coronary diseases, and the indications are expanding internationally. Based on the latest research from china and elsewhere, the Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon has updated the previous DCB consensus after evidence-based discussions and meetings in terms of adequate preparation of in-stent restenosis lesions, expansion of the indications for coronary de novo lesions, and precise guidance of DCB treatment by intravascular imaging and functional evaluation.

关键词： balloon drugs dealing

Boundary conditions for the bending of a piezoelectric beam

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2.& ZHAO BaoSheng3 1 College of Science, china Agricultural {2., Beijing 100083, china 2.College of engineering, ocean university of china, Qingdao 2.6071, china 3 School of Mechanical engineering, {2. of Science and Technology Liaoning, Anshan 114044, china College of Science China Agricultural University Beijing China College of engineering Ocean University of China Qingdao China School of Mechanical engineering University of Science and Technology Liaoning Anshan China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Mixed boundary conditions for piezoelectric plates

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2.&ZHAO BaoSheng 3 1College of Science,china Agricultural {2.,Beijing 100083,china 2.ollege of engineering,ocean university of china,Qingdao 2.6071,china 3 School of Mechanical engineering,{2. of Science and Technology of Liaoning,Anshan 114044,china College of Science China Agricultural University Beijing China College of engineering Ocean University of China Qingdao China School of Mechanical engineering University of Science and Technology of Liaoning Anshan China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems