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Solubilities of CO2 in some glycol ethers under high pressure by experimental determination and correlation

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Chinese Journal of Chemical Engineering 2016年第3期24卷 373-378页

作者： Wei Wang zhi Yun zhigang Tang xia Gui College of Chemistry and Chemical Engineering Nanjing University of TechnologyNanjing 210009China State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

The binary vapor–liquid equilibrium data of CO_2 in diethylene glycol(monomethyl,monoethyl,monobutyl,dimethyl,diethyl,dibutyl)ether were determined from 288.15 to 318.15 K at pressure up to 6 MPa based on the constant-volume *** was found by contrast that the ether group in solvents can promote the CO_2 absorption,but the hydroxyl group will inhibit the CO_2 ***,the solubilities of CO_2 showed an upward trend with the increasing molecular lengths of *** experimental data were also correlated with a modified Patel–Teja equation of state(PT EOS)combined with the traditional van der Waals one-fluid mixing rules and the results showed a satisfactory agreement between the model and the experimental data.

关键词： Vapor-liquid equilibrium CO2D iethylene glycol ethers PT EOS

Evaluation of vehicle-track-bridge interacted system for the continuous CRTS-II non-ballast track slab

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Science China(Technological Sciences) 2014年第10期57卷 1895-1901页

作者： ZHANG nan ZHOU Shuang xia He SUN Lu School of Civil Engineering Beijing Jiaotong University School of Transportation Southeast University

Considering the CRTS-II track slab,which is commonly used in the Chinese high-speed railway system,a vehicle-track-bridge dynamic analysis method is proposed in which the vehicle subsystem equations are established by the rigid body dynamics method,the track subsystem and the bridge subsystem equations are established by the FEM,the wheel-rail contact relation is defined by the corresponding assumption in vertical direction and the Kalker linear creep theory in lateral *** in-span spring element is derived to model the track-bridge interaction;the equal-band-width storage is adopted to fit the track structure with multilayer uniform section beam;and the dynamic equilibrium equations are solved by the inter-history iteration *** a case study,the response of a CRH2 high-speed train transverses a simply-supported bridge with successive 31.5m double bound pre-stress beams is *** result shows that using the vehicle-track-bridge interaction model instead of the vehicle-bridge interaction model helps predict the rotation angle at beam ends and choose an economic beam vertical stiffness.

关键词： vehicle-track-bridge interacted system CRTS-II track slab in-span spring element equal-band-width storage

Vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges

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Science China(Technological Sciences) 2015年第2期58卷 236-247页

作者： LI Yong Le SU Yang xia Fei Long ZHANG nan Department of Bridge Engineering Southwest Jiaotong University MOE Key Laboratory of High Speed Railway Engineering Southwest Jiaotong University Department of Bridge Engineering Northern Jiaotong University

An analytical model is presented to study vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges based on an explicit dynamic analysis *** the model,the train,ballastless track and bridge are treated as a coupled vibration system with *** simulating the dynamic process of the system,this paper discusses the distribution law of dynamic responses of the bridge deck and the bed *** shows the necessity of a base plate for the ballastless track on the long-span plate-truss cable-stayed *** of the influence of different train speeds and stiffness of the elastic vibration-damping pad on the dynamic responses of the bridge deck and the bed slab is also *** reasonable stiffness value of elastic vibration-damping pad is proposed.

关键词： long-span cable-stayed bridge plate-truss girder ballastless track train-induced vibration vehicle-bridge system

The model study of water mass and energy exchange between the inland water body and atmosphere

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Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1010-1021页

作者： SUN ShuFen YAN JinFeng xia nan LI Qian LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China Graduate University of Chinese Academy of Sciences Beijing 100010China

Based on a one-dimensional eddy diffusion model,a model to study the water mass and energy exchange between the water body(such as lake and wetland) and the atmosphere is developed,which takes the phase change process due to the seasonal melting and freezing of water and the convection mixing process of energy caused by temperature stratification into consideration. The model uses enthalpy instead of temperature as predictive variable,which will help to deal with the phase change process and to design an efficient numerical scheme for obtaining the solution more easily. The performance of the model and the rationality of taking convection mixing into the consideration are validated by using observed data of Kinneret Lake in Israel and Lower Two Medicine Lake in Montana State in America. The comparison of model results with observed data indicates that the model presented here is capable of describing the physical process of water mass and energy between the water body(lake and wetland) and atmosphere. Comparison of the result from wetland with shallow and deep lakes under the same forcing conditions shows that the evaporation from wetland is much greater than that from lakes,which accords with the real observation fact and physical mechanism.

关键词： water body model wetland and lake environment fluid heat exchange between water body and atmosphere latent heat

Recursion Formulae for Obtaining Surfaces with Constant MeanCurvature inR^2,1

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Communications in Theoretical Physics 2007年第2期47卷 203-208页

作者： TIAN Yong-Bo nan zhi-Jie TIAN Chou Department of Mathematics University of Science and Technology. of China Hefei 230026China

Though the Bǎcklund transformation on time-like surfaces with constant mean curvature surfaces in R^2,1 has been obtained, it is not easy to obtain corresponding surfaces because the procedure of solving the related integrable system cannot be avoided when the Bǎcklund transformation is used, For sake of this, in this article, some special work is done to reform the Bǎcklund transformation to a recursion formula, by which we can construct time-like surfaces with constant mean curvature form known ones just by quadrature procedure.

关键词： Bǎcklund transformation time-like surfaces with mean curvature Lax pairs recursion formula

Effect of interface behaviour on damage and instability of PBX under combined tension-shear loading

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Defence Technology（防务技术） 2023年第5期23卷 137-151页

作者： Quan-zhi xia Yan-qing Wu Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid system, which introduces a nonlinear plastic damage cohesion model to study the mechanical response and damage process. The parameters in the model were fitted and *** the crack growth rate as the feature, the damage state in each stage was determined, and the damage instability criterion was given. The effects of interfacial tensile strength and shear strength on the damage process of PBX were studied. On this basis, serrated and hemispherical structures interface of PBX has been developed, which affects the damage process and instability during the loading *** results indicate that damage state response of PBX experiences the process of stable load bearing,unstable propagation, and complete failure. At the critical moment of instability, the overall equivalent effective strain of material reaches 3024 με and instability loading displacement reaches 0.39 mm. The increase of interfacial tensile strength and shear strength significantly inhibits the damage of PBX. The effect of interfacial shear strength on critical instability of PBX is approximately 1.7 times that of the interfacial tensile strength. Further, interface opening along the normal direction is the main damage form at the interface. Serrated and hemispherical rough interfaces can significantly inhibit propagation of cracks, and the load bearing capacity is improved by 22% and 9.7%, respectively. Appropriate improvement of the roughness of the interface structure can effectively improve the mechanical properties. It is significantly important to have a better understanding of deformation, damage and failure mechanisms of PBX and to improve our predictive ability.

关键词： PBX explosives Interface behaviour Damage Instability Crack propagation

Recent advances in prevention of hepatitis B recurrence after liver transplantation

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World Journal of Gastroenterology 2015年第3期21卷 829-835页

作者： zhi-Feng Xi Qiang xia Department of Liver Surgery Ren Ji HospitalSchool of MedicineShanghai Jiaotong University

Liver transplantation is the only effective treatment for hepatitis B virus(HBV)-related end-stage liver ***,without antiviral prophylaxis,the recurrence rate of hepatitis B is as high as 80%-100%,which leads to a 50% mortality rate in the first 2 years after liver *** therapy of hepatitis B immunoglobulin(HBIG) and lamivudine demonstrated a higher efficacy of prophylaxis and further reduced the rate of recurrence to < 10%.The strategy of HBIG combined with lamivudine has been the standard treatment in many ***,the high rate of lamivudine resistance and the many disadvantages of HBIG have compelled surgeons to reconsider the longterm efficacy of this strategy for the prevention of HBV ***,new nucleos(t)ide analogues,such as entecavir and tenofovir,have been approved as first-line monotherapies for the treatment of chronic hepatitis B *** antiviral medicines have replaced lamivudine as the first choice in the prevention of HBV recurrence after liver *** therapies that are composed of entecavir,tenofovir,and lamivudine plus adefovir,with or without HBIG have been adopted in several liver transplant *** article reviews the recent advances in prophylaxis for the recurrence of hepatitis B after liver transplantation.

关键词： Liver transplantation Hepatitis B recurrence Hepat

Medium optimization for enhanced production of cytosine-substituted mildiomycin analogue (MIL-C) by Streptoverticillium rimofaciens ZJU 5119

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第1期9卷 77-84页

作者： Dan YE zhi-nan XU Pei-lin CEN Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Cytosine-substituted mildiomycin analogue （MIL-C） was produced effectively by supplementing cytosine into the culture of Streptoverticillium rimofaciens. In order to improve the yield of MIL-C, statistically-based experimental designs were applied to optimize the fermentation medium for S. rimofaciens ZJU 5119. Fifteen culture conditions were examined for their significances on MIL-C production using Plackett-Burman design. The Plackett-Burrnan design and one-variable-at-a-time design indicated that glucose and rice meal as the complex carbon sources, and peanut cake meal and NH4NO3 as the complex nitrogen sources were beneficial for MIL-C production in S. rimofaciens ZJU 5119. The results of further central composition design （CCD） showed that the optimal concentration of glucose, rice meal and peanut cake meal were 18.7 g/L, 64.8 g/L and 65.1 g/L, respectively. By using this optimal fermentation medium, the MIL-C concentration was increased up to 1336.5 mg/L, an approximate 3.8-fold improvement over the previous concentration （350.0 mg/L） with un-optimized medium. This work will be very helpful to the large-scale production of MIL-C in the future.

关键词： Cytosine-substituted mildiomycin analogue (MIL-C) Plackett-Burman design Response surface methodology Streptoverticillium rimofaciens Nucleoside antibiotic

A multiaxial elastic potential with error-minimizing approximation to rubberlike elasticity

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Acta Mechanica Sinica 2015年第5期31卷 637-646页

作者： zhi-xiang Gu Lu Yuan Zheng-nan Yin Heng xiao State Key Laboratory of Advanced Special Steels Shanghai University Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

This study is concerned with a new,explicit approach by means of which forms of the large strain elastic potential for multiaxial rubberlike elasticity may be obtained based on data for a single deformation *** a departure from usual studies,here for the first time errors may be estimated and rendered minimal for all possible deformation modes and,furthermore,failure behavior may be *** examples presented are in accurate agreement with Treloar＇s well-known data.

关键词： Rubberlike elasticity Large deformations Elastic potential Explicit approach Minimized errors