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Chinese Physics Letters 2012年第6期29卷 211-214页

作者： s.hussain Theoretical Plasma Physics Division PINSTECHNiloreIslamabad 44000Pakistan Department of Physics and Applied Mathematics PIEAs NiloreIslamabad 44000Pakistan

Nonlinear ion-acoustic solitary wave structures in collisionless,non-relativistic,homogenous,magneto-rotating plasma,in which the electron species follow the kappa distribution function,are *** Korteweg-de Vries (KdV) equation is derived by using the reductive perturbation method,and the effects of different plasma parameters on the obliquely propagating nonlinear solitary wave structures in the magneto-rotating plasma are *** is noticed that the spectral index parameter κ significantly modifies the nonlinear wave structure.

关键词： structure rotating solitary

Reliable Field Distortion spark Gap for Plasma Focus

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Plasma science and Technology 2007年第4期9卷 504-507页

作者： s.hussain M.ZAKAULLAH Department of Physics University of Sargodha40100 SargodhaPakistan Department of Physics Quaid-i-Azam University45320 IslamabadPakistan

A simple, low cost, easily maintained, and reliable field distortion spark gap has been developed to operate at a voltage up to 30 kV. The header construction necessary to attach the spark gap switch to a single 12.5 μF, 40 kV （10 k J） capacitor is described. The main features of the spark gap are its wide range of voltage operation, high current capacity, low inductance and long lifetime. The performance of spark gap has been tested in a plasma focus and results are presented in this report.

关键词： field distortion spark gap plasma focus

ON A CLAss OF ANALYTIC FUNCTIONs RELATED TO CONIC DOMAINs AND AssOCIATED WITH CARLsON-sHAFFER OPERATOR

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Acta Mathematica scientia 2012年第4期32卷 1399-1407页

作者： s.hussain J.sokól Mathematics Department COMSATS Institute of Information TechnologyAbbottabadPakistan Department of Mathematics Rzeszów University of Technologyul.W.Pola 235-959 RzeszówPoland

Making use of the Carlson-shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. some applications are also discussed.

关键词： Hadamard product (or convolution) differential subordination Carlson-shaffer operator k-starlike functions k-uniformly convex function

Physiological Flow of Jeffrey six Constant Fluid Model due to Ciliary Motion

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Communications in Theoretical Physics 2016年第12期65卷 701-708页

作者： A.shaheen s.hussain s.Nadeem Department of Mathematics Capital University of Science and Technology Department of Mathematics Quaid-i-Azam University

The main purpose of this article is to present a mathematical model of ciliary motion in an annulus. In this analysis, the peristaltic motion of non-Newtonian Jeffrey six constant fluid is observed in an annulus with ciliated tips in the presence of heat and mass transfer. The effects of viscous dissipation are also considered. The flow equations of non-Newtonian fluid for the two-dimensional tube in cylindrical coordinates are simplified using the low Reynolds number and long wave-length approximations. The main equations for Jeffrey six constant fluid are considered in cylindrical coordinates system. The resulting nonlinear problem is solved using the regular perturbation technique in terms of a variant of small dimensionless parameter α. The results of the solutions for velocity, temperature and concentration field are presented graphically. B_k is Brinkman number, sT is soret number, and sH is the schmidth number. Outcome for the longitudinal velocity, pressure rise, pressure gradient and stream lines are represented through graphs. In the history, the viscous-dissipation effect is usually represented by the Brinkman number.

关键词： ciliary motion metachronal wave Jeffrey six-constant fluid viscous dissipation effects and perturbation method

Non Planar Electrostatic solitary Wave structures in Negative Ion Degenerate Plasma

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Chinese Physics Letters 2011年第4期28卷 148-151页

作者： s.hussain N.Akhtar saeed-ur-Rehman Theoretical Plasma Physics Division PINSTECHNiloreIslamabad Department of Physics and Applied Mathematics PIEAs NiloreIslamabad

Theoretical and numerical studies are performed for quantum ion acoustic solitons in planar and non-planar geometries in an unmagnetized homogenous plasma consisting of warm positive and negative ions with nonthermal electrons.A deformed Korteweg de Vries(DKdV)equation is derived by using the reductive perturbation *** numerical solution to the DKdV equation indicates that the quantum parameter,temperatures of positive ions,temperture of negative ions and electron density blatantly influence the propagation speed and the structure of quantum ion acoustic *** geometrical effects on the structure of quantum ion acoustic wave are *** is shown that the amplitude and propagation speed in spherical geometry is larger as compared to cylinderical and planar geometries for different values of the above-mentioned parameters.

关键词： method quantum planar

Magnetosonic shocks in Ultra-Relativistic Dissipative Degenerate Plasmas

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Chinese Physics Letters 2016年第8期33卷 77-80页

作者： s.hussain N.Akhtar N.Mustafa Theoretical Physics Division PINSTECHP.O.Nilore

Magnetosonic shock structures in dissipative magnetized degenerate electron ion plasma are studied. The two fluid quantum magnetohydrodynamic equations for non-degenerate ions and ultra-relativistic degenerate electron fluids with the Maxwell equations are presented. Using the reductive perturbation technique the Korteweg de Vries Burgers （KdVB） equation is derived and its solution is presented with the tanh method. Astrophysical plasma parameters are used to study the effects of variation of plasma density, magnetic field intensity and kinematic viscosity on the propagation characteristics of nonlinear shock structures in such plasma systems.

关键词： in on is et de of that

Low Energy Plasma Focus as an Intense X-ray source for Radiography

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Plasma science and Technology 2004年第3期6卷 2296-2300页

作者： s.hussain M.Zakaullah shujaat Ali A.Waheed Department of Physics Quaid-i-Azam University 45320 Islamabad PakistanDepartment of Physics Quaid-i-Azam University 45320 Islamabad PakistanDepartment of Physics Quaid-i-Azam University 45320 Islamabad PakistanPINSTECH P. O. Box 2151 44000 Islamabad Pakistan

study on X-ray emission from a low energy (1.8 kJ) plasma focus devicepowered by a 9 μF capacitor bank, charged at 20 kV and giving peak discharge current of about 175kA by using a lead-inserted copper-tapered anode is reported. The X-ray yield in different energywindows is measured as a function of hydrogen filling pressure. The maximum yield in 4π-geometry isfound to be (27.3+-1.1) J and corresponding wall plug efficiency for X-ray generation is 1.52+-0.06%. X-ray emission, presumably due to bombarding activity of electrons in current sheath at theanode tip was dominant, which is confirmed by the pinhole images. The feasibility of the device asan intense X-ray source for radiography is demonstrated.

关键词： plasma focus X-ray source radiography

Conjugate natural convection of non-Newtonian hybrid nanofluid in wavy-shaped enclosure

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Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 447-466页

作者： s.hussain T.TAYEBI T.ARMAGHANI A.M.RAsHAD H.A.NABWEY Department of Mathematics Capital University of Science and TechnologyIslamabad 44000Pakistan Lehrstuhl III Department of MathematicsTechnical University of DortmundDortmund 44227Germany Faculty of sciences and Technology University of Bordj Bou ArreridjEl-Anasser 34030Algeria Department of Engineering West Tehran BranchIslamic Azad UniversityTehran 11365Iran Department of Mathematics Aswan UniversityFaculty of ScienceAswan 81528Egypt Department of Mathematics College of Science and Humanities in Al-KharjPrince Sattam Bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Basic Engineering science Faculty of EngineeringMenou¯a UniversityShebin El-Kom 32511Egypt

The present study concerns the modelization and numerical simulation for the heat and flow exchange characteristics in a novel configuration saturated with a nonNewtonian Ag-MgO hybrid *** wavy shaped enclosure is equipped with onequarter of a conducting solid *** system of equations resulting from the mathematical modeling of the physical problem in its dimensionless form is discretized via the higher-order Galerkin-based finite element method(GFEM).The dependency of various factors and their interrelationships affecting the hydro-thermal behavior and heat exchange rate are *** numerical experiments reveal that the best heat transfer rate is achieved for the pseudo-plastic hybrid nanoliquid with high Rayleigh number and thermal conductivity ratio and low Hartmann ***,the power-law index has a major effect in deteriorating the heat convection at high Rayleigh number.

关键词： natural convection waved-shaped cavity magnetic field hybrid nanofluid higher order finite element method(FEM)

Wheat-Exuded Organic Acids Influence Zinc Release from Calcareous soils

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Pedosphere 2011年第5期21卷 657-665页

作者： M.A.MAQsOOD s.hussain T.AZIZ M.AsHRAF Institute of soil and Environmental sciences University of Agriculture Department of soil science University of Sargodha

Rhizosphere drives plant uptake of sparingly soluble soil zinc(Zn).An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes(sehar-06 and Vatan),Zn fractions in 10 different calcareous soils from Punjab,Pakistan,and release of different soil Zn fractions by organic *** two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient *** a deficient Zn level,sehar-06 released more maleic acid in the rhizosphere than *** soils used in the present study had very different physicochemical properties;their total Zn and Zn distribution among different fractions varied *** release behaviour was determined by extracting the soils with 0.005 mol L-1 citric acid or maleic *** parabolic diffusion model best described Zn release as a function of *** diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different *** Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg-1 using maleic acid and from 0.37 to 11.84 mg kg-1 using citric *** the selected calcareous soils,the results of stepwise linear regression indicated significant release of Fe-Mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-effcient ***,release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.

关键词： citric acid maleic acid phytoavailability plant uptake rhizosphere

MHD stagnation Point Flow of Williamson Fluid over a stretching Cylinder with Variable Thermal Conductivity and Homogeneous/Heterogeneous Reaction

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Communications in Theoretical Physics 2017年第6期67卷 688-696页

作者： M.Bilal M.sagheer s.hussain Y.Mehmood Department of Mathematics Capital University of Science and Technology

The present study reveals the effect of homogeneous/hetereogeneous reaction on stagnation point flow of Williamson fluid in the presence of magnetohydrodynamics and heat generation/absorption coefficient over a stretching cylinder. Further the effects of variable thermal conductivity and thermal stratification are also considered. The governing partial differential equations are converted to ordinary differential equations with the help of similarity *** system of coupled non-linear ordinary differential equations is then solved by shooting technique. MATLAB shooting code is validated by comparison with the previously published work in limiting case. Results are further strengthened when the present results are compared with MATLAB built-in function bvp4c. Effects of prominent parameters are deliberated graphically for the velocity, temperature and concentration profiles. skin-friction coefficient and Nusselt number for the different parameters are investigated with the help of tables.

关键词： stagnation point flow homogeneous/heterogeneous reaction Williamson fluid stretching cylinder variable thermal conductivity thermal stratification