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A Fully Flexible Potential Model for Carbon Dioxide

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Chinese Journal of Chemical Engineering 2009年第2期17卷 268-272页

作者：朱爱梅张新波刘庆林张秋根 National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Department of Chemical and Biochemical Engineering College of Chemistry & Chemical Engineering Xiaman University Xiamen 361005 China

A fully flexible potential model for carbon dioxide has been developed to predict the vapor-liquid coexistence properties using the NVT-Gibbs ensemble Monte Carlo technique(GEMC).The average absolute deviation between our simulation and the literature experimental data for saturated liquid and vapor densities is 0.3% and 2.0%,*** with the experimental data,our calculated results of critical properties(7.39 MPa,304.04 K,and 0.4679 g?cm-3) are acceptable and are better than those from the rescaling the potential parameters of elementary physical model(EPM2).The agreement of our simulated densities of supercritical carbon dioxide with the experimental data is acceptable in a wide range of pressure and *** radial distribution function estimated at the supercritical conditions suggests that the carbon dioxide is a nonlinear molecule with the C O bond length of 0.117 nm and the O C O bond angle of 176.4°,which are consistent with Car-Parrinello molecular-dynamics(CPMD),whereas the EPM2 model shows large deviation at supercritical *** predicted self-diffusion coefficients are in agreement with the experiments.

关键词： molecular simulations radial distributions fully flexible potential model carbon dioxide

Recipient dendritic cells modified by RNA interference targeting CD80 and CD86 elicit T cell hyporesponsiveness via enhanced T cell apoptosis

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Chinese Medical Journal 2013年第11期126卷 2139-2144页

作者： HONG Jun GU Xiao-dong XIANG Jian-bin ZHANG Zhe ZANG Yi-wen ZHANG Qun-hua QIAN Shi-guang CHEN Zong-you Department of General Surgery Huashan Hospital FudanUniversity Shanghai 200040 China Department of Immunology and General Surgery Lerner ResearchInstitute Cleveland Clinic Foundation Cleveland OH 44195 USA

Background Despite extensive research, the mechanism of immature dendritic ceils （DCs） induced immune hyporesponsiveness remains incompletely understood. Methods Recipient DCs from C3H mouse bone marrow cells were incubated with donor antigen from splenic lymphocytes of C57BL/6 mouse; these DCs were transfected with CD80/86 specific siRNA using lentiviral vectors. Flow cytometry was used to evaluate expression of CD80/86 on the antigen-pulsed recipient DCs. Immune regulatory activity was examined by mixed lymphocyte reaction, in which irradiated DCs were cultured with C3H spleen T cells. After the reaction, interleukin （IL）-2, IL-4, IL-10, and interferon （INF）-~ levels of mixed lymphocyte reaction culture supernatant were measured by enzyme-linked immunosorbent assay. The apoptotic T lymphocytes were identified by Annexin V and CD3 staining. Results There was a significant inhibition of CD80/86 expression in DCs transfected with CD80/86 lentiviral vectors compared with the control groups （P 〈0.05）, indicating the specificity of RNA interference. Enzyme-linked immunosorbent assay results showed a significant reduction of INF-γ, IL-2 and IL-10 in the CD80/86 lentivirus transfected group compared to the control groups （P 〈0.05）. There was no significant difference in IL-4 levels between the groups （P 〉0.05）. We also showed that CD80/86 low DCs loaded with alloantigen （1） stimulated low T cell proliferative responses via the indirect recognition pathway and （2） enhanced apoptotic activity （P 〈0.05） in co-cultured T cells. Conclusions Lentiviral vector transfection can effectively and specifically knock down target genes in DCs. The CD80/86 low DCs may show tolerogenic activity via induction of T-cell apoptosis, thereby modulating the activity of recipient-derived DCs. The use of this approach may potentially be clinicallv applicable.

关键词： dendritic cell T cell apoptosis RNA interference

Four optimal design approaches of high-order finite-impulse response filters based on neural network

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Journal of Central South University of Technology 2007年第1期14卷 94-99页

作者：王小华何怡刚刘美容 School of Electrical and Information Engineering Hunan University

Four optimal approaches of high-order finite-impulse response(FIR) digital filters were developed for designing four types filters using neural network algorithms. The solutions were presented as parallel algorithms to approximate the desired frequency response specification. Therefore, these methods avoid matrix inversion, and make a fast calculation of the filter’s coefficients possible. The convergence theorems of these proposed algorithms were presented and proved to illustrate them stable, and the implementation of these methods was described together with some design guidelines. The simulation results show that the ripples of the designed FIR filters are significantly little in the pass-band and stop-band, and the proposed algorithms are of fast convergence.

关键词： high-order finite-impulse response digital filter frequency response neural network convergence theorem

Stochastic stability of networked control systems with network-induced delay and data dropout

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控制理论与应用（英文版） 2008年第4期6卷 405-409页

作者： Xiaomei ZHANG Yufan ZHENG Guoping LU School of Science Nantong University Nantong Jiangsu 226007 China Institute of Systems Science Shanghai University Shanghai 200436 China College of Electrical Engineering Nantong University Nantong Jiangsu 226007 China

This paper deals with the stochastic stability of networked control systems with the presence of network- induced delay and transmitted data dropout. Based on the Lyapunov approach, sufficient conditions for the mean-square stability of the networked control system are derived subject that the sequence of transmission interval is driven by an identically independently distributed sequence and by a finite state Markov chain, respectively. Stabilization controllers are constructed in terms of linear matrix inequalities correspondingly. An example is provided to illustrate our results.

关键词： Networked control systems Network-induced delay Data dropout Lyapunov method Linear matrix inequalities

The Flow Simulation and Experimental Study of Low-Specific-Speed High-Speed Complex Centrifugal Impellers

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Chinese Journal of Chemical Engineering 2006年第4期14卷 435-441页

作者：崔宝玲朱祖超张剑慈陈鹰 State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 china Zhejiang Provincial Key Lab of Modern Textile Machinery Zhejiang Sci-Tech University Hangzhou 310018 china Department of Mechanical Engineering Western College Zhejiang University of Technology Quzhou 324000 china State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 china

Based on the Navier-Stokes equations and the Spalart-Allmaras turbulence model, three-dimensional turbulent flow in four low-specific-speed centrifugal impellers are simulated numerically and analyzed. The relative velocity distribution, pressure distribution and static pressure rise at the design point are obtained for the regular impeller with only long blades and three complex impellers with long, mid or short blades. It is found that the back flow region between long-blade pressure side and mid-blade suction side is diminished and is pushed to pressure side of short blades near the outlet of impeller at suction side by the introduction of mid, short blades, and the size of back flow becomes smaller in a multi-blade complex impeller. And the pressure rises uniformly from inlet to outlet in all the impellers. The simulated results show that the complex impeller with long, mid and short blades can improve the velocity distribution and reduce the back flow in the impeller channel. The experimental results show that the back flow in the impeller has an important influence on the performance of pump and a more-blade complex impeller with long, mid and short blades can effectively solve low flow rate instability of the low-specific-speed centrifugal pump.

关键词： centrifugal pump low-specific-speed complex impeller flow simulation high speed experimental study

Relativistic Brueckner-Hartree-Fock Theory for Finite Nuclei

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Chinese Physics Letters 2016年第10期33卷 40-44页

作者：申时行胡金牛梁豪兆孟杰 Peter Ring 张双全 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University RIKEN Nishina Center Department of Physics Nankai University Department of Physics Graduate School of ScienceThe University of Tokyo School of Physics and Nuclear Energy Engineering Beihang University Department of Physics University of Stellenbosch Physik-Department der Technischen Universitt München

Starting with a bare nucleon-nucleon interaction, for the first time the full relativistic Brueckner Hartree-Fock equations are solved for finite nuclei in a Dirac-Woods-Saxon basis. No free parameters are introduced to calculate the ground-state properties of finite nuclei. The nucleus 160 is investigated as an example. The resulting groundstate properties, such as binding energy and charge radius, are considerably improved as compared with the non-relativistic Brueckner-Hartree-Fock results and much closer to the experimental data. This opens the door for ab initio covariant investigations of heavy nuclei.

关键词： in with for of Relativistic Brueckner-Hartree-Fock Theory for Finite Nuclei RHF been body is

Preparation and properties of gradient Al_2O_3-ZrO_2 ceramic foam by centrifugal slip casting method

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china Foundry 2012年第4期9卷 337-343页

作者： i Qiang Yu Jingyuan Tang Ji Qi Guochao Li Xiaodong College of Materials Science and Engineering Liaoning University of TechnologyJinzhou 121001China Shenyang Research Institute of Foundry Shenyang 110022China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110004China

The aim of the present research is to provide a novel technique for preparing gradient Al 2 O 3-ZrO 2 ceramic *** technique used epispastic polystyrene spheres to array templates and centrifugal slip casting to obtain cell struts with gradient distribution of Al 2 O 3 and ZrO 2 particles and high packing *** Al 2 O 3-20vol.% ZrO 2 slurries with 20vol.% solid contents were prepared and the dispersion and rheological characteristics of the slurries were *** settling velocity and mass segregation of Al 2 O 3 and ZrO 2 particles at different centrifugal accelerations were calculated and *** drying behavior,macrostructure,microstructure,compressive property and resistance to thermal shock of the sintered products were also *** results show that the difference of settling velocity of Al 2 O 3 and ZrO 2 particles increases and mass segregation becomes acute with an increase in centrifugal *** cell struts prepared at a centrifugal acceleration of 1,690 g have high sintered density(99.0% TD) and continuous gradient distribution of Al 2 O 3 and ZrO 2 *** sintered at 1,550 o C for 2 h,the cell size of gradient Al 2 O 3-ZrO 2 foam is approximately uniform,about 1.1 *** the porosity of gradient Al 2 O 3-ZrO 2 ceramic foams increasing from 75.3% to 83.0%,the compressive strength decreases from 4.4 to 2.4 MPa,and the ceramic foams can resist 8-11 repeated thermal shock from 1,100 o C to room temperature.

关键词： ceramic foam centrifugal slip casting settling velocity gradient distribution compressive property

MIXED DISCONTINUOUS GALERKIN TIME-STEPPING METHOD FOR LINEAR PARABOLIC OPTIMAL CONTROL PROBLEMS

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Journal of Computational Mathematics 2015年第2期33卷 158-178页

作者： Tianliang Hou Yanping Chen School of Mathematical Sciences South China Normal University Guangzhou 510631 China School of Mathematics and Statistics Beihua University Jilin 132013 China

In this paper, we discuss the mixed discontinuous Galerkin （DG） finite element ap- proximation to linear parabolic optimal control problems. For the state variables and the co-state variables, the discontinuous finite element method is used for the time dis- cretization and the Raviart-Thomas mixed finite element method is used for the space discretization. We do not discretize the space of admissible control but implicitly utilize the relation between co-state and control for the discretization of the control. We de- rive a priori error estimates for the lowest order mixed DG finite element approximation. Moveover, for the element of arbitrary order in space and time, we derive a posteriori L2（O, T; L2（Ω）） error estimates for the scalar functions, assuming that only the underlying mesh is static. Finally, we present an example to confirm the theoretical result on a priori error estimates.

关键词： A priori error estimates A posteriori error estimates Mixed finite element,Discontinuous Galerkin method Parabolic control problems.

Microstructure evolution and oxidation states of Co in perovskite-type oxide Ba_(1.0)Co_(0.7)Fe_(0.2)Nb_(0.1)O_(3-δ) annealed in CO_2 atmosphere

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Journal of Energy Chemistry 2014年第5期23卷 575-581页

作者： Chengzhang Wu He Wang Xingxing Zhang Yuwen Zhang Weizhong Ding Chenghua Sun Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University School of Chemistry Monash University Clayton VIC 3800 Australia

Ba1.0Co0.7Fe0.2Nb0.1O3-γ（BCFN） oxide with perovskite cubic structure was synthesized by solid state reaction method. COa corrosion of BCFN membrane was investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, diffuse reflectance infrared Fourier- transformed spectroscopy （DRIFT） and X-ray absorption fine structure spectroscopy （XAFS）. Cobalt （Co） K-edge absorption spectra of BCFN annealed in COa reveal that the oxidation states of Co in all the samples were larger than ＋3 and they decreased with the increase of calcination time. At 800 ℃, 1% CO2 introduced into He could speed up the reduction of Co cations in comparison with pure He. In addition, sulfate ions in the bulk of BCFN membrane preferred to migrate to the surface under CO2 calcination and form monoclinic Ba（CO3）0.9（SO4）0.1 besides orthorhombic witherite. Moreover, SEM results indicate that the nucleation and growth of carbonates grains started at the grain boundary of the membrane.

关键词： perovskite oxygen permeation carbon dioxide corrosion sulfate