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MG132 Induced Apoptosis Pathway in HL-60 Cells and Impact of Allogeneic Mixed Lymphocyte Reaction 被引量:2
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作者 Yong-ming Zhou Wei Guo +3 位作者 Hao Zhou Jin-hua Zhang Zhi-ping Liu Mei-xia Yu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2009年第4期333-339,共7页
Objective: To investigate the proteasome inhibitor MG132-induced apoptosis pathway in HL-60 cells and the role of allogeneic mixed lymphocyte reaction. Methods: Cell apoptosis was analyzed by flow cytometry. The ex... Objective: To investigate the proteasome inhibitor MG132-induced apoptosis pathway in HL-60 cells and the role of allogeneic mixed lymphocyte reaction. Methods: Cell apoptosis was analyzed by flow cytometry. The expressions of p21 protein, p27 protein and p53 protein in HL-60 ceils treated with MG132 were measured by Western blot. The proliferation of, peripheral blood mononuclear cells (PBMNCs) after treatment with 75 Gy irradiated HL-60 cells treated with MG132 was measured with CCK-8. Results: High-dose MG132 induced apoptosis in HL-60 cells. No significant change was observed in MG132-induced apoptosis after inhibiting caspase-8 and caspase-9 pathway. The expressions of p21 protein and p27 protein increased in MG132-induced apoptosis. HL-60 cells treated with low-dose MG132 improved the proliferation of PBMNCs from healthy volunteers. Conclusion: High-dose MG132 induced apoptosis and directly killed HL-60 ceils. MG132 induced apoptosis in a caspase-8- and caspase-9-independent pathway, p21 protein and p27 protein were involved in MG132-induced apoptosis in HL-60 cells. HL-60 cells treated with Low-dose MG132 improved the effect of promoting the proliferation of PBMNCs from healthy volunteers. 展开更多
关键词 Proteasome inhibitor MG132 APOPTOSIS p21 protein p27 protein Allogeneic mixed lymphocyte reaction
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IMPAIRED AUTOLOGOUS MIXED LYMPHOCYTE REACTION CORRELATED WITH DECREASED EXPRESSION OF HLA-Ⅱ ANTIGENS ON MONOCYTES IN PATIENTS WITH MYELOID LEUKEMIA
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作者 龚非力 H.Grosse Wilde 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第2期14-20,共7页
The proliferative response of T-cells to autolo-gous non-T-cells is referred to as the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that AMLR represents a mechanism of immune regulation i... The proliferative response of T-cells to autolo-gous non-T-cells is referred to as the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that AMLR represents a mechanism of immune regulation in vivo. We investigated AMLR in patients with acute- and chronic myeloid leukemia (AML and CML). AMLR was found to be significantly depressed (P<0.001) in AML patients (n=17, cpm=532±95) and CML patients (n=13, cpm=688±99) when compared with that of their healthy HLA-identical siblings serving as controls (n=17, cpm=4152±619 and n=13 cpm=4086±421, respectively). In order to understand the cellular basis of the defective AMLR in patients with AML end CML, we performed mitogen-treated T-cell cultures analysis of T-cell subsets and HLA-Ⅱ antigen detection on monocytes. The results indicated that the defect of AMLR in patients resided at the stimulator monocyte level rather than at the responder T-cell level. Enumeration of monocytes reactive with monoclonal antibody Tu22, which recognizes determinants of HLA-DQ, demonstrated that ML patients had a significantly decreased (P<0.091) number of circulating Tu22+ monocytes when compared with normal controls. These studies suggest that a deficiency of HLA-DQ+ monocytes contributes to the depression of AMLR in ML and possibly underlies the abnormalities of immune response present in this disease. 展开更多
关键词 AMLR IMPAIRED AUTOLOGOUS mixed lymphocyte reaction CORRELATED WITH DECREASED EXPRESSION OF HLA ANTIGENS ON MONOCYTES IN PATIENTS WITH MYELOID LEUKEMIA
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Ni_(3)Fe/Ni_(4)S_(3)/Ni/C Mixed Crystal Composite Nanofibers Prepared by Electrospinning and Heat Treatment Methods for Oxygen Evolution Reaction 被引量:2
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作者 LI Tao ZHONG Shujie +5 位作者 LOU Qiongyue LING Shuai CHEN Jian MA Guohua YANG Mao WU Xiaoqiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期267-273,共7页
OER catalyst of Ni_(3)Fe/Ni_(4)S_(3)/Ni/C(NiFeSC series)mixed crystal composite nanofibers was prepared by electrospinning and atmospheric heat treatment process.The testing results indicate that the diameters of Ni_(... OER catalyst of Ni_(3)Fe/Ni_(4)S_(3)/Ni/C(NiFeSC series)mixed crystal composite nanofibers was prepared by electrospinning and atmospheric heat treatment process.The testing results indicate that the diameters of Ni_(3)Fe/Ni_(4)S_(3)/Ni/C composite nanofibers is about 200 nm,the grains size is about 1-3 nm,and the fiber surface is rough.The electrochemical test results show that the heterojunction of the prepared Ni_(3)Fe/Ni_(4)S_(3)/Ni/C hybrid crystal composite nanofiber has synergistic effect with sulfide,and exhibits good electrocatalytic activity of water decomposition and OER in alkaline system.The OER electrocatalytic performance of Ni_(3)Fe/Ni_(4)S_(3)/Ni/C composite electrode prepared via a heat treatment at 1000℃process was tested in 1 mol/L KOH electrolytes.The results show that the overpotential is about 298 mV,the Tafel slope is about 74 mV?dec-1,and the surface resistance is about 1.69Ω·cm^(2),at the current density of 10 mA·cm^(-2). 展开更多
关键词 mixed crystal composite material NANOFIBER NiFeSC oxygen evolution reaction(OER)
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Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO_(2)into glycerol carbonate
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作者 Xufang Chen Xin Shu +5 位作者 Yanru Zhu Jian Zhang Zhigang Chai Hongyan Song Zhe An Jing He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期153-163,共11页
Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The dire... Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The direct carbonylation from glycerol with CO_(2)is considered a promising route,but still tough work due to the thermodynamic stability and the kinetic inertness of CO_(2).In this work,highlyselective direct carbonylation of glycerol and CO_(2)into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides(MgInCe-MMO),which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides(MgInCe-LDHs).By precisely modulating the surface basic-acidic properties and the oxygen vacancies,an efficient carbonylation of glycerol with CO_(2)has been achieved with a selectivity of up to>99%to glycerol carbonate.Deep investigation into the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified. 展开更多
关键词 Catalytic reaction engineering Glycerol carbonate Direct carbonylation from glycerol Carbon dioxide mixed metal oxides Synergistic catalysis
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Effect of New Immunosuppressant-Rapamycin on One-way Mixed Lymphocyte Culture
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作者 夏国伟 张元芳 丁强 《Journal of Nanjing Medical University》 2004年第6期323-325,共3页
Objective: Observing human to mouse one-way mixed lymphocyte culture(xMLC) and the effect of new immunosuppressant-Rapamycin on XMLC. Methods: Mouse splenic lymphocyte were collected and treated by mitomycin as activa... Objective: Observing human to mouse one-way mixed lymphocyte culture(xMLC) and the effect of new immunosuppressant-Rapamycin on XMLC. Methods: Mouse splenic lymphocyte were collected and treated by mitomycin as activating cell; Human Peripheral blood lymphocytes(hPBL)were separated and gathered as reacting cell; Mouse splenic lymphocyte and hPBL wee mixed to incubate for 1 week; The researchers designed control、RPM groups,and experiment(drugs)grup have different concentration. Results: HPBL in the experiment groups (mixed mouse lymphocyte)proliferated obviously,the amount of3H-TdR in corporation increased evidently(P<0 05,The mean percentage of CD 4, CD 8, LgG, LgM positive cells rose markedly. HPBL in the experiment groups less proliferated,the amount of 3H-TdR incorporation declined,RPM's ic50(50%inhibition concentration)approximately in 1.5 nmol/L; the mean percentage of CD 4, CD 8, IgG, IgM positive cells fell obviously. Conclusion: The human to mouse one-way MLC has obvious lymphocyte proliferation. New immunosuppressants-Rapamycin have powerful effete on XMLC. 展开更多
关键词 mixed lymphocyte culture IMMUNOSUPPRESSANT RAPAMYCIN
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Mixed lymphocyte reaction induced by multiple alloantigens and the role for IL-10 in proliferation inhibition 被引量:2
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作者 Junyi Zhou Weifeng He +1 位作者 Gaoxing Luo Jun Wu 《Burns & Trauma》 SCIE 2014年第1期24-28,共5页
The frequency of T cells that can respond to alloantigens is unusually high.It remains unclear how T cells would respond when stimulated by multiple major histocompatibility complex(MHC)disparate alloantigens in the s... The frequency of T cells that can respond to alloantigens is unusually high.It remains unclear how T cells would respond when stimulated by multiple major histocompatibility complex(MHC)disparate alloantigens in the same cultures.In this report,we examined potential interactions of T cell clones that were stimulated simultaneously by two sets of complete MHC disparate alloantigens using mixed lymphocyte reaction(MLR).In this assay,we observed that proliferation of B6 lymphocytes(H-2b)stimulated by both BALB/c(H-2d)and C_(3)H(H-2k)allogeneic cells was not increased but rather reduced as compared to B6 cells stimulated with either BALB/c or C_(3)H allogeneic cells.Interestingly,interleukin(IL)-10 expressions at both protein level and mRNA level was signifi cantly increased in cultures stimulated with the two MHC alloantigens,while IL-2,tumor necrosis factor(TNF)-α,transforming growth factor(TGF)-β1 production did not show any differences.In addition,Foxp_(3) mRNA expression was comparable amongst all groups.In conclusion,we observed an inhibitory effect in T cell proliferation in response to multiple MHC mismatched alloantigens in MLR,and this effect might be associated with the upregulation of IL-10 expression. 展开更多
关键词 INTERLEUKIN-10 T-lymphocyteS intraclonal competition mixed lymphocyte reaction
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Thermal Behavior,Nonisothermal Decomposition Reaction Kinetics of Mixed Ester Double-base Gun Propellants 被引量:6
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作者 YI Jian-hua ZHAO Feng-qi XU Si-yu GAO Hong-xu HU Rong-zu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第5期608-614,共7页
The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate(TEGDN) and nitroglycerin(NG) were investigated by... The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate(TEGDN) and nitroglycerin(NG) were investigated by thermogravimetry(TG) and differential thermogravimetry(DTG), and differential scanning calorimetry(DSC) under the high-pressure dynamic ambience. The results show that the thermal decomposition processes of the mixed nitric ester gun propellants have two mass-loss stages. Nitric ester evaporates and decomposes in the first stage, and nitrocellulose and centralite II(C2) decompose in the second stage. The mass loss, the DTG peak points, and the terminated temperatures of the two stages are changeable with the difference of the mass ratio of TEGDN to NG. There is only one obvious exothermic peak in the DSC curves under the different pressures. With the increase in the furnace pressure, the peak temperature decreases, and the decomposition heat increases. With the increase in the content of TEGDN, the decomposition heat decreases at 0.1 MPa and rises at high pressure. The variety of mass ratio of TEGDN to NG makes few effect on the exothermic peak temperatures in the DSC curves at different pressures. The kinetic equation of the main exothermal decomposition reaction of the gun propellant TG0601 was determined as: dα/dt=1021.59(1-α)3e-2.60×104/T. The reaction mechanism of the process can be classified as chemical reaction. The critical temperatures of the thermal explosion(Tbe and Tbp) obtained from the onset temperature(Te) and the peak temperature(Tp) are 456.46 and 473.40 K, respectively. ΔS≠, ΔH≠, and ΔG≠ of the decomposition reaction are 163.57 J·mol^-1·K^-1, 209.54 kJ·mol^-1, and 133.55 kJ·mol^-1, respectively. 展开更多
关键词 mixed nitric ester gun propellant Triethyleneglycol dinitrate Thermal behaviors Nonisothermal decomposition reaction kinetics
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Numerical investigation of variable viscosities and thermal stratification effects on MHD mixed convective heat and mass transfer past a porous wedge in the presence of a chemical reaction 被引量:2
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作者 I. Muhaimin R. Kandasamy Azme B. Khamis 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1353-1364,共12页
An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid... An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid past a porous wedge in the presence of a chemical reaction. The wall of the wedge is embedded in a uniform nonDarcian porous medium in order to allow for possible fluid wall suction or injection. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically with finite difference methods. Numerical calculations up to the thirdorder level of truncation are carried out for different values of dimensionless parameters. The results are presented graphically, and show that the flow field and other quantities of physical interest are significantly influenced by these parameters. The results are compared with those available in literature, and show excellent agreement. 展开更多
关键词 variable viscosity chemical reaction non-Darcy flow mixed convection thermal stratification magnetic effect
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Mixed convection effects on heat and mass transfer in a non Newtonian fluid with chemical reaction over a vertical plate
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作者 D.R.V.S.R.K.Sastry A.S.N.Murti +1 位作者 P.K.Kameswaran T.P.Kantha 《Theoretical & Applied Mechanics Letters》 CAS 2011年第4期64-67,共4页
This paper studies mixed convection,double dispersion and chemical reaction effects on heat and mass transfer in a non-Darcy non-Newtonian fluid over a vertical surface in a porous medium under the constant temperatur... This paper studies mixed convection,double dispersion and chemical reaction effects on heat and mass transfer in a non-Darcy non-Newtonian fluid over a vertical surface in a porous medium under the constant temperature and concentration.The governing boundary layer equations,namely,momentum,energy and concentration,are converted to ordinary differential equations by introducing similarity variables and then are solved numerically by means of fourth-order Runge-Kutta method coupled with double-shooting technique.The velocity,temperature concentration,heat and mass transfer profiles are presented graphically for various values of the parameters,and the influence of viscosity index n,thermal and solute dispersion,chemical reaction parameter χ are observed. 展开更多
关键词 chemical reaction double dispersion mixed convection heat and mass transfer
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Unsteady mixed convection flow over stretching sheet in presence of chemical reaction and heat generation or absorption with non-uniform slot suction or injection
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作者 R.RAVINDRAN N.SAMYUKTHA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第10期1253-1272,共20页
The article examines the unsteady mixed convection flow over a vertical stretching sheet in the presence of chemical reaction and heat generation or absorption with non-uniform mass transfer. The unsteadiness is cause... The article examines the unsteady mixed convection flow over a vertical stretching sheet in the presence of chemical reaction and heat generation or absorption with non-uniform mass transfer. The unsteadiness is caused by the time dependent free stream velocity varying arbitrarily with time. Non-similar solutions are obtained nu- merically by solving the coupled nonlinear partial differential equations using the quasi- linearization technique in combination with an implicit finite difference scheme. To reveal the tendency of the solutions, typical results for the local skin friction coefficient and the local Nusselt and Sherwood numbers are presented for different values of parameters. The effects of various parameters on the velocity, temperature, and concentration distributions are discussed here. The present numerical results are compared with the previously published work, and the results are found to be in excellent agreement. 展开更多
关键词 unsteady mixed convection non-similar solution non-uniform slot suction stretching sheet chemical reaction heat generation
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Discrete formulation of mixed finite element methods for vapor deposition chemical reaction equations
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作者 罗振东 周艳杰 朱江 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第5期665-675,共11页
The vapor deposition chemical reaction processes, which are of extremely extensive applications, can be classified as a mathematical model by the following governing nonlinear partial differential equations containing... The vapor deposition chemical reaction processes, which are of extremely extensive applications, can be classified as a mathematical model by the following governing nonlinear partial differential equations containing velocity vector, temperature field, pressure field, and gas mass field. The mixed finite element (MFE) method is employed to study the system of equations for the vapor deposition chemical reaction processes. The semidiscrete and fully discrete MFE formulations are derived. And the existence and convergence (error estimate) of the semidiscrete and fully discrete MFE solutions are demonstrated. By employing MFE method to treat the system of equations for the vapor deposition chemical reaction processes, the numerical solutions of the velocity vector, the temperature field, the pressure field, and the gas mass field can be found out simultaneously. Thus, these researches are not only of important theoretical means, but also of extremely extensive applied vistas. 展开更多
关键词 vapor deposition chemical reaction equation the mixed finite element method semidiscrete formulation fully discrete formulation
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Effects of the Water in Mixed Solvent on the Epoxidation Reaction of Propylene with TS-1 Catalyst
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作者 苏泉声 王彪 +1 位作者 张玉梅 王华平 《Journal of Donghua University(English Edition)》 EI CAS 2001年第4期70-73,共4页
The epoxidation reaction of propylene and hydrogen peroxide with zeolite catalyst containing titaniumsilicalite (TS-1)has been studied, and the reaction in the mixed solvent of water/methanol has been discussed. It is... The epoxidation reaction of propylene and hydrogen peroxide with zeolite catalyst containing titaniumsilicalite (TS-1)has been studied, and the reaction in the mixed solvent of water/methanol has been discussed. It is shown that the selective of epoxidation propylene decreases while the selective of propylene glycol increases, when the water content increases in the mixed solvent of methanol/water. 展开更多
关键词 titanium-silicalite TS-1/SiO2 epoxidation reaction methanol/water mixed solvent
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A Second Order Characteristic Mixed Finite Element Method for Convection Diffusion Reaction Equations
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作者 Tongjun Sun 《Journal of Applied Mathematics and Physics》 2017年第6期1301-1319,共19页
A combined approximate scheme is defined for convection-diffusion-reaction equations. This scheme is constructed by two methods. Standard mixed finite element method is used for diffusion term. A second order characte... A combined approximate scheme is defined for convection-diffusion-reaction equations. This scheme is constructed by two methods. Standard mixed finite element method is used for diffusion term. A second order characteristic finite element method is presented to handle the material derivative term, that is, the time derivative term plus the convection term. The stability is proved and the L2-norm error estimates are derived for both the scalar unknown variable and its flux. The scheme is of second order accuracy in time increment, symmetric, and unconditionally stable. 展开更多
关键词 mixed Finite Element METHOD CHARACTERISTIC METHOD Second Order Accuracy CONVECTION Diffusion reaction EQUATIONS
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STUDIES ON THE CHROMOPHORIC REACTIONS OF MIXED POLYNUCLEAR COMPLEXES OF RARE EARTH-ARSENAZO Ⅲ-COPPERO-PHENANTHROLINE
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作者 沈含熙 凌蓉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第3期218-223,共6页
In an acidic solution the mixed polynuclear complexes could be formed by association of rareearth-arsenazo Ⅲ complexing anions with copper o-phenanthrolinate cations.In this paper the formationconditions of lanthanum... In an acidic solution the mixed polynuclear complexes could be formed by association of rareearth-arsenazo Ⅲ complexing anions with copper o-phenanthrolinate cations.In this paper the formationconditions of lanthanum-arsenazo Ⅲ-copper-o-phenanthroline complex and its related reaction mechanismhave been studied in detail.The complex exhibits an absorption maximum at 663 nm and its apparent molarabsorptivity is found to be 1.22×105L·mol-1·cm-1.The molar ratio of the components in the complex isestimated to be La:arsenazo Ⅲ:Cu:Phen=1:1:1:3.Its possible molecular formula can expressed as[Cu(Phen)3](La-arsenazo Ⅲ).The reaction is used to determine micro amounts of lanthanum(or rareearths)in copper containning synthetic samples and satisfactory results are obtained. 展开更多
关键词 La STUDIES ON THE CHROMOPHORIC reactionS OF mixed POLYNUCLEAR COMPLEXES OF RARE EARTH-ARSENAZO COPPERO-PHENANTHROLINE
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MHD Mixed Convection Flow of a Casson Fluid over an Exponentially Stretching Surface with the Effects of Soret, Dufour, Thermal Radiation and Chemical Reaction
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作者 Kankanala Sharada Bandari Shankar 《World Journal of Mechanics》 2015年第9期165-177,共13页
The present study deals with MHD (magneto hydrodynamics) mixed convection flow of a Casson fluid over an exponentially stretching sheet with the effects of Soret and Dufour, thermal radiation, chemical reaction. The g... The present study deals with MHD (magneto hydrodynamics) mixed convection flow of a Casson fluid over an exponentially stretching sheet with the effects of Soret and Dufour, thermal radiation, chemical reaction. The governing partial differential equations are converted into ordinary differential equations by using similarity transformations. These equations are then solved numerically by applying finite difference scheme known as the Keller Box method. The effects of various parameters on velocity, temperature and concentration profiles are presented graphically to interpret and the results are discussed. 展开更多
关键词 Casson Fluid Magneto Hydrodynamics mixed Convection EXPONENTIALLY STRETCHING Surface SORET and Dufour EFFECTS Thermal Radiation Chemical reaction
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Analysing the cause of sever blood transfusion reaction caused by mixed anti-body of anti-Jk^b and anti-E
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《中国输血杂志》 CAS CSCD 2001年第S1期381-,共1页
关键词 body Analysing the cause of sever blood transfusion reaction caused by mixed anti-body of anti-Jk^b and anti-E
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Mixed Reaction to Proposed Dual Standards for Birth Control
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《China Population Today》 2002年第Z1期19-20,共2页
关键词 mixed reaction to Proposed Dual Standards for Birth Control
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Application of donor dendric cell mediated recipieut lymphocyte reaction after related kidney transplantation in individualized immunosuppressive therapy
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作者 黄赤兵 《外科研究与新技术》 2011年第4期283-284,共2页
Objective To explore the feasibility of mediating recipient lymphocyte reaction with donor dendritic cells ( Dcs) in renal allograft recipients to guide individualized immunosuppressive therapy. Methods From Jan. 2008... Objective To explore the feasibility of mediating recipient lymphocyte reaction with donor dendritic cells ( Dcs) in renal allograft recipients to guide individualized immunosuppressive therapy. Methods From Jan. 2008 to Jan. 2010,30 recipients received living related kidney transplantation were successively and divided into 展开更多
关键词 Application of donor dendric cell mediated recipieut lymphocyte reaction after related kidney transplantation in individualized immunosuppressive therapy
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Reaction process of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl_2 被引量:12
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作者 吴文远 边雪 +2 位作者 吴志颖 孙树臣 涂赣峰 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第4期864-868,共5页
The decomposition reactions of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2 were studied by means of TG-DTA and XRD. The results show that the process of the minerals decomposed by CaO... The decomposition reactions of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2 were studied by means of TG-DTA and XRD. The results show that the process of the minerals decomposed by CaO involves two steps. The first step occurs in the temperature range of 425-540 ℃, and the main reactions are bastnaesite decomposition, i.e. REOF reacts with CaO to produce RE2O3 and CaF2, and Ce2O3 is oxidized to CeO2. During this step, CaCO3 is formed at about 500 ℃. The second step takes place in the temperature range of 610-700 ℃, and the reactions are monazite decomposition into RE2O3, Ca5F(PO4)3 and Ca3(PO4)2 by CaO and CaF2. In this process, the decomposition ability is improved because CaO from CaCO3 decomposing has high chemical activity. In calcining process, the new formed Ca5F(PO4)3 restrains fluorine that can escape in form of gaseous compound. The decomposition ratio of the mixed rare earth minerals reaches 90.8% at 700 ℃. 展开更多
关键词 稀土矿物 煅烧 氧化钙 氯化钠 氯化钙 氟碳铈矿 独居石 分解反应
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Preparation and characterization of Cu-Ce-La mixed oxide as water-gas shift catalyst for fuel cells application 被引量:2
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作者 智科端 刘全生 +2 位作者 赵瑞岗 何润霞 张利峰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第4期538-543,共6页
Cu-Ce-La mixed oxides were prepared by three precipitation methods (coprecipitation, homogeneous precipitation, and deposition precipitation) with variable precipitators and characterized using X-ray diffraction, BE... Cu-Ce-La mixed oxides were prepared by three precipitation methods (coprecipitation, homogeneous precipitation, and deposition precipitation) with variable precipitators and characterized using X-ray diffraction, BET, temperature-programmed reduction, and catalytic reaction for the water-gas shift. The Cu-Ce-La mixed oxide prepared by coprecipitation method with NaOH as precipitator presented the highest activity and thermal stability. Copper ion substituted quadrevalent ceria entered CeO2 (111) framework was in favor of activity and thermal stability of catalyst. The crystallinity of fresh catalysts increased with the reduction process. La^3+ or Ce^4+ substituted copper ion entered the CeO2 framework during reduction process. The coexistence of surface copper oxide (crystalline) and pure bulk crystalline copper oxide both contributed to the high activity and thermal stability of Cu-Ce-La mixes oxide catalyst. 展开更多
关键词 Cu-Ce-La mixed oxide water-gas shift reaction PRECIPITATION precipitator rare earths
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