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Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2.& XU WeiSheng 2.1 college of Hydraulic and environmental {2.,china Three Gorges University,Yichang 443002.china 2.college of Hydropower {2.,Xi’an University of Technology,Xi’an 710048,china college of Hydraulic and environmental {2. China Three Gorges University Yichang China college of Hydropower engineering Xi’an University of Technology Xi’an China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

Polyaniline Supported 12.Tungstosilicic Acid as the Catalyst for Acetals and Ketals Synthesis

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 371-375页

作者：杨永金 PHILIPPE G Merle hubei Key Laboratory of Pollutant Analysis & Reuse Technology College of Chemistry and Environmental Engineering Hubei Normal University department of Chemistry and Biochemistry Concordia University

A novel environmental friendly catalyst, H4SiW12.40/PAn was prepared and identified by FT-IR, XRD and TG/DTA. The optimal synthetic protocol was a PAn to H4SiW12.40 mass ratio of 1 ： 1, a 2. mL of methanol and a reaction time of 2.h at reflux. It was used in catalytic synthesis of ten important ketals and acetals with a high catalytic activity. With an aldehyde/ketone to glycol molar ratio of 1 ： 1.5 and a 1 wt% catalyst loading, the yields of ketals and acetals could reach 60.0%- 93.8 % after 1 h.

关键词： 12.tungstosilicic acid polyaniline acetal ketal catalysis

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2.YANG Mo1 & XU PeiWei2.1 college of Power engineering,University of Shanghai for Science and Technology,Shanghiai 2.0093,{2. 2.department of environmental engineering,Jilin Architectural and Civil engineering Institute,Changchun 13002.,{2. college of Power engineering University of Shanghai for Science and Technology Shanghiai China department of environmental {2. Jilin Architectural and Civil Engineering Institute Changchun China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

Oxidation rate in the preparation of polyferric sulfate coagulant

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Journal of environmental Sciences 2001年第1期13卷 104-107页

作者： CHANG Qing (department of environmental {2., Lanzhou Railway college, Lanzhou 730070, china.E\|mail:changq@***) 兰州铁道大学甘肃兰州 730070

The oxidation rate of ferrous sulfate was investigated in the preparation of polyferric sulfate(PFS) coagulant. It was proved that this reaction is zero order with respect to Fe2., first order with respect to NO2.g) and first order with respect to the interface area between gas phase and liquid phase. If the partial pressure of NO2.g) in gas phase is increased or the interface area is increased, the time needed to complete the reaction will be decreased.

关键词： coagulant flocculant polyferric sulfate PFS oxidation rate water treatment

Formation of the Inclusion Complex of Orange Ⅱ with β-Cyclodextrin and Its Photostability

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Wuhan University Journal of Natural Sciences 2003年第4期 1147-1152页

作者： Lu Ping 1,2., Liu Bin 1,3 , Zhang Zhe 1 , Wu Feng 1 , Deng Nan-sheng 1 1. college of Resource and environmental Science, Wuhan University, Wuhan 430072.{2., china 2. School of Chemistry and environmental engineering, Jianghan University , Wuhan 430056,{2., china 3. department of environmental and Chemical engineering, Huangshi Polytechnic college, Huangshi 435003,{2., china

Inclusion complex of Orange II with β-Cyclodextrin （β-CD） and the anti-photolysis effect under UV-light were investigated. The molar ratio of inclusion complex of β-Cyclodextrin and Orange Ⅱ is 1∶1. The formation constant K=1.2.6×10 3 L/mol was determined by the UV and Fluorescence spectra respectively, which was quite in accordance with the calculation with a modified Benesi-Hildbrand equation. The inclusion complex was characterized by the IR spectra and the molar ratio of inclusion complex is 1∶1 too. The formation constant K=1.2.6×10 3 L/mol was determined by 1 H NMR analysis and was nearly the same by UV and fluorescence spectra. The photocatalytic decolorization rate of Orange Ⅱ solutions containing β-CD and TiO_ 2.was smaller by 51.9% than that of the Orange Ⅱ solutions only containing TiO_ 2., while in the case of direct photolysis of Orange Ⅱ solutions, β-CD can lower the photolysis rate by 48.1% under UV-light. This result indicates β-CD can inhibit the photolysis and photocatalytic decolorization of Orange Ⅱ under UV-light. The β-CD inclusion complex was found to be persistent to UV-light photolysis.

关键词： β-Cyclodextrin Orange Ⅱ inclusion complex photostability

The refined theory of deep rectangular beams for symmetrical deformation

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 919-925页

作者： GAO Yang1 & WANG MinZhong2.1 college of Science, china {2. University, Beijing 100083, china 2.State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace engineering, Peking University, Beijing 100871, china college of Science China Agricultural University Beijing China State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace engineering Peking University Beijing China

Based on elasticity theory, various one-dimensional equations for symmetrical deformation have been deduced systematically and directly from the two-dimensional theory of deep rectangular beams by using the Papkovich-Neuber solution and the Lur'e method without ad hoc assumptions, and they construct the refined theory of beams for symmetrical deformation. It is shown that the displacements and stresses of the beam can be represented by the transverse normal strain and displacement of the mid-plane. In the case of homogeneous boundary conditions, the exact solutions for the beam are derived, and the exact equations consist of two governing differential equations: the second-order equation and the transcendental equation. In the case of non-homogeneous boundary conditions, the approximate governing differential equations and solutions for the beam under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively, and the correctness of the stress assumptions in classic extension or compression problems is revised. Meanwhile, as an example, explicit expressions of analytical solutions are obtained for beams subjected to an exponentially distributed load along the length of beams.

关键词： deep rectangular beams the refined theory symmetrical deformation the Papkovich-Neuber solution the Lur’e method

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 {2. University, Beijing 100083, china 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science, Peking University, Beijing 100871, china college of Science China Agricultural University Beijing China State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and engineering Science Peking University Beijing 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

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

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.

Synthesis and luminescent properties of Eu^(3+)-doped Na_(2.)As_2._(2.)O_(83)

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Rare Metals 2003年第2期22卷 95-97页

作者： YANGShuijin YUANLiangjie SUNJutang departmentofChemistryandenvironmental{2. HubeiNormalUniversityHuangshi435002China collegeofChemistryandMolecularSciences WuhanUniversityWuhan430072China

The Eu^(3+)-doped Na^(2.)As_2._(2.)O_83 phosphor has been prepared by solidstare reaction from Na_3AsO_4.12._2., Na_2.O_4.2._2. and WO_3, and characterized by elementalanalysis, infrared spectroscopy and powder X-ray diffractometry. According to the measurements withX-ray diffraction, this material belongs to orthorhombic system with its lattice constants: avelence 1.4750 nm, b velence 1.1944 nm, c velence 1.1062.nm, it is consistent with space groupD_2.4-P2.12.12.1 (No.19). The emission and excitation spectra were measured. The luminescentproperties of Eu^(3+)-doped Na^(2.)As_2._(2.)O_83 and mechanism of energy transfer were discussed.

关键词： Heteropolytungstate europium ion crystal structure synthesis luminescence