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Note on characteristics of homogeneous-heterogeneous reaction in flow of Jeffrey fluid

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Applied mathematics and mechanics(English Edition) 2015年第10期36卷 1319-1328页

作者： m.FAROOQ A.ALSAEDI t.HAYAt Department of mathematics Quaid-i-Azam University Nonlinear Analysis and Applied mathematics (NAAm) Research Group Faculty of Science King Abdulaziz University

this letter describes the characteristics of homogeneous-heterogeneous re- action in the boundary layer flow of a Jeffrey fluid due to an impermeable horizontal stretching sheet. An analysis is carried out through the similar values of reactant and auto catalyst diffusion coefficients. Heat released by the reaction is not accounted. the exact solution for the flow of the Jeffrey fluid is constructed. the series solution for the concentration equation is derived. the velocity and concentration fields reflecting the impact of interesting parameters are plotted and examined.

关键词： Jeffrey fluid stretching sheet homogeneous-heterogeneous reaction

Effects of homogeneous-heterogeneous reactions in flow of Powell-Eyring fluid

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Journal of Central South University 2015年第8期22卷 3211-3216页

作者： t.Hayat m.Imtiaz A.Alsaedi Department of mathematics Quaid-I-Azam University NAAm Research Group Department of Mathematics Faculty of ScienceKing Abdulaziz University

the steady two-dimensional flow of Powell-Eyring fluid is investigated. the flow is caused by a stretching surface with homogeneous-heterogeneous reactions. the governing nonlinear differential equations are reduced to the ordinary differential equations by similarity transformations. the analytic solutions are presented in series forms by homotopy analysis method(HAm). Convergence of the obtained series solutions is explicitly discussed. the physical significance of different parameters on the velocity and concentration profiles is discussed through graphical illustrations. It is noticed that the boundary layer thickness increases by increasing the Powell-Eyring fluid material parameter(ε) whereas it decreases by increasing the fluid material parameter(δ). Further, the concentration profile increases when Powell-Eyring fluid material parameters increase. the concentration is also an increasing function of Schmidt number and decreasing function of strength of homogeneous reaction. Also mass transfer rate increases for larger rate of heterogeneous reaction.

关键词： Powell-Eyring fluid boundary layer flow stretching sheet homogeneous-heterogeneous reactions

time-Dependent Cylindrical and Spherical Solitary Structures and Double Layers of Dust Ion-Acoustic Waves in Ultra-Relativistic Dense Plasma

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Communications in theoretical Physics 2013年第6期59卷 745-750页

作者： t.Akhter m.m.Hossain A.A.mamun Department of Physics Jahangirnagar University

Cylindrical and spherical (nonplanar) solitary waves (SWs) and double layers (DLs) in a multi-ion plasma system (containing inertial positively as well as negatively charged ions, non-inertial degenerate electrons, and negatively charged static dust) are studied by employing the standard reductive perturbation method. the modified Gardner (mG) equation describing the nonlinear propagation of the dust ion-acoustic (DIA) waves is derived, and its nonplanar SWs and DLs solutions are numerically analyzed. the parametric regimes for the existence of SWs, which are associated with both positive and negative potential, and DLs which are associated with negative potential, are obtained. the basic features of nonplanar DIA SWs, and DLs, which are found to be different from planar ones, are also identified.

关键词： solitary waves double layers ultra-relativistic dense plasma dust ion acoustic waves Gardnerequation

Numerical and Experimental Investigation on the In-Flight melting Behaviour of Granulated Powders in Induction thermal Plasmas

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Plasma Science and technology 2009年第1期11卷 71-77页

作者：姚耀春 md.m.HOSSAIN t.WAtANABE National Engineering Laboratory of Vacuum metallurgy Kunming University of Science and Technology Department of Environmental Chemistry and Engineering Tokyo Institute of Technology Department of Electronics and Communications Engineering East West University

An innovative in-flight glass melting technology with thermal plasmas was developed for the purpose of energy conservation and environment protection. In this study, modelling and experiments of argon-oxygen induction thermal plasmas were conducted to investigate the melting behaviour of granulated soda-lime glass powders injected into the plasma. A two-dimensional local thermodynamic equilibrium （LtE） model was performed to simulate the heat and momentum transfer between plasma and particle. Results showed that the particle temperature was strongly affected by the flow rate of carrier gas and the particle size of raw material. A higher flow rate of carrier gas led to lower particle temperature and less energy transferred to particles which resulted in lower vitrification. the incomplete melting of large particles was attributed to the lower central temperature of the particle caused by a larger heat capacity. the numerical analysis explained well the experimental results, which can provide valuable practical guidelines for the process control in the melting process for the glass industry.

关键词： induction thermal plasmas size. heat transfer numerical modelling carrier gas flow rate particle

Boundary layer flow of Oldroyd-B fluid by exponentially stretching sheet

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Applied mathematics and mechanics(English Edition) 2016年第5期37卷 573-582页

作者： t.HAYAt m.ImtIAZ A.ALSAEDI Department of mathematics Quaid-i-Azam University Department of mathematics Faculty of Science King Abdulaziz University

the present paper investigates the steady flow of an Oldroyd-B fluid. the fluid flow is induced by an exponentially stretched surface. Suitable transformations reduce a system of nonlinear partial differential equations to a system of ordinary dif- ferential equations. Convergence of series solution is discussed explicitly by a homotopy analysis method （HAm）. Velocity, temperature and heat transfer rates are examined for different involved parameters through graphs. It is revealed that for a larger retardation time constant, the velocity is enhanced and the temperature is lowered. It is noted that relaxation time constant and the Prandtl number enhance the heat transfer rate.

关键词： Oldroyd-B fluid homotopy analysis method (HAm) exponentially stretch-ing sheet

Review:Resuspension of wall deposits in spray dryers

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1762-1774页

作者： HANUS m.J. LANGRISH t.A.G. School of Chemical and Biomolecular Engineering University of Sydney Sydney NSW 2006 Australia

Wall deposition occurs in spray dryers when dried or partially dried particles contact and adhere to the walls during operation, thus reducing the yield of product collected. Wall deposits also present a product contamination risk and a fire or explosion risk when spray drying products that oxidize exothermically, such as milk powder. Re-entrainment is the resuspension of spray dryer wall deposits into the main gas stream for collection as product. Literature suggests that the process for re-entrainment of particles from spray dryer wall deposits is strongly dependent on particle size and gas velocity.

关键词： Wall deposition Spray dryers Dried particles Re-entrainment Adhesive forces

Biological transformation,kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure

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Journal of Environmental Sciences 2008年第7期20卷 878-884页

作者： m A mottaleb J H Zimmerman t W moy Department of Chemistry and Biochemistry Baylor UniversityP.O.Box 97348WacoTX 76798USA. U.S.Environmental Protection Agency National Exposure Research LaboratoryEnvironmental Sciences Division944 East Harmon AveLas VegasNV 89119USA

Low levels (ng/g) of musk ketone (mK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other ***,aquatic organisms can be continuously exposed to *** this study,kinetics and dose-response assessments of 2-amino-mK (AmK) metabolite,bound to cysteine-hemoglobin (Hb) in rainbow trout,formed by enzymatic nitro-reduction of mK have been *** were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg mK/g ***...

关键词： biotransformation kinetics hemoglobin adducts dose-response nitro musks biomarker fish

Studies of multilayer structure in depth direction by soft X-ray spectroscopy

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Nuclear Science and techniques 2006年第5期17卷 257-267页

作者： m. WAtANABE t. EJImA N. mIYAtA t. ImAZONO m. YANAGIHARA Shanghai Dianji University Institute of Composite materials Shanghai Jiaotong University Shanghai 200030 China Saga University Synchrotron Light Application Center Japan Institute of multidisciplinary Research for Advanced materials Tohoku University Japan Institute of multidisciplinary Research for Advanced materials Tohoku University

It is demonstrated that two kinds of soft X-ray spectroscopy are useful as nondestructive methods to in- vestigate multilayer structures modified by interdiffusion or by chemical reaction of adjoining layers in depth direc- tion. One is the total electron yield (tEY) spectroscopy involving angular dependence measurement. Using this method, it was found that in LiF/Si/LiF trilayers, the Si layers exhibited a characteristic similar to porous Si, and in CaF2/Si/CaF2 trilayers, it was found that CaF2 segregated through the Si layer. moreover, it has been shown that the thickness of the top layer of a mo/Si X-ray multilayer can be determined by analyzing tEY signals generated by the standing wave. the other is the soft X-ray emission spectroscopy involving spectral shape analysis. Using this method, it was found that in mo/Si X-ray multilayers, the interdiffusion or chemical reaction giving rise to deterioration of re- flectance character occurs in as-deposited samples as well as in heated samples. In antiferromagnetic Fe/Si multilay- ers, it was confirmed that there was no existence of pure Si layers, but insulating FeSi2 layers were present. this result suggests that the source of antiferromagnetic coupling is not conduction electrons but quantum wave interference.

关键词：软X射线能谱多层结构景深方向总电子流量驻波硅化合物

High-frequency induction heated sintering of ball milled Fe-WC nanocomposites

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International Journal of minerals,metallurgy and materials 2013年第7期20卷 693-699页

作者： m. Zakeri t. Zanganeh A. Najafi Ceramic Department Materials and Energy Research Center P.O. Box 31787/316 Karaj Iran Department of materials Saveh Branch Islamic Azad University Saveh Iran

Fe-WC nanocomposites were successfully fabricated by high-frequency induction heated sintering of ball milled nanostructure powders. the ball milled powders were characterized by X-ray diffraction. Density measurements by the Archimedes method show that all sintered samples have the relative density higher than 95%. Studies on the effects of WC content, milling speed, and milling time indicate that a higher milling speed and a more WC content lead to the improvement of mechanical properties. there is a very good distribution of WC particles in the Fe matrix at the milling speed of 650 r/rain. For the sintered sample 20-5-650 （20wt% WC, milling time of 5 h, and milled speed of 650 r/min）, the maximum Brinell hardness and yield stress are obtained to be 3.25 GPa and 858 mPa, respectively. All sintered samples have brittle fracture during compression test except the sample 20-5-650.

关键词： nanocomposites metallic matrix composites iron tungsten carbide induction heating sintering mechanicalproperties