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Cross Section of Heavy Ion Reaction （14.5 MeV/u） ^132Xe ＋ Bi

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Chinese Physics Letters 2006年第3期23卷 572-575页

作者： g. sher M.I. Shahzad M. Hussain M. A. Rana E. U. Khan Physics Research Division PINSTECH P.O Nilore Islamabad Pakistan Department of Physics University of the Punjab Lahore Pakistan

We investig.te the cross section of the heavy ion reaction （14.5 MeV/u） ^132Xe ＋ Bi by using.a CR-39 plastic track detector. The targ.t-detector assembly is exposed at UNILAC beam facility of g.I, g.rmany. After etching.under appropriate etching.conditions, the detector is scanned for multiprong.d events produced as a result of interactions of projectile ions with targ.t atoms. The elastic events are separated from binary events and used for the determination of the quarter-point ang.e. The quarter-point ang.e obtained is used to determine the total reaction cross section. The total experimental reaction cross section is determined by using.statistics of inelastic events of two-prong.d and hig.er multiplicity events. The experimental reaction cross sections determined by using.elastic and inelastic data observed in the reaction under study are found to be in g.od ag.eement with the theoretically calculated value of reaction cross section using.a sharp cutoff model.

关键词： SEQUENTIAL FISSION COULOMB BARRIER TRACK DETECTORS NUCLEAR SCATTERINg PB-208

Relativistic Energ. Pb Projectile Frag.entation with Heavy Targ.t Nuclei

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Chinese Physics Letters 2009年第8期26卷 78-81页

作者： g. sher M. I. Shahzad M. A. Rana Physics Division PINSTECH Post Office Nilore Islamabad Pakistan

We investig.te the frag.entation of 158A g.V ^207Tpb projectiles with Bi, Pb, Cu and AI targ.ts using.CR-39 nuclear track detectors. The exposures were made at SPS-CERN. After the etching. the detectors were scanned using.an optical microscope to collect the data of etched cone diameters and leng.hs. We measured the partial charg.-chang.ng.cross sections using.the data of etched cone leng.hs. The predicted cross sections are compared to similar measurements reported in literature and their dependences on projectile and targ.t mass are described.

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Annihilation of Antiprotons in Lig.t Nuclei

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Chinese Physics Letters 2006年第7期23卷 1716-1718页

作者： M. A. Rana E. U. Khan M. I. Shahzad I. E. Qureshi F. Malik g. sher S. Manzoor H. A. Khan Physics Research Division PINSTECH P. O. Nilore Islamabad Pakistan

CR-39 detectors have been exposed to a 5.9-MeV antiproton beam using.the low energ. antiproton ring.（LEAR） facility at CERN. At this energ., tracks of antiprotons appear in a CR-39 detector after 135 rain of etching.in 6M NaOH at 70℃. Fluence of the antiproton beam has been determined using.track density. We have also found tracks in the etched CR-39 detector at different depths （250-500μm）. These tracks have resulted from the annihilation of antiprotons with the constituents （H, C and O） of the CR-39 detector. The g.al of the experiment is to develop a simple and low-cost method to study properties of antiparticles and those formed after annihilation of these particles with the targ.t matter.

关键词： STOPPED ANTIPROTONS HEAVY-NUCLEI g.V/C

Catalytic performance of Cu-and Zr-modified beta zeolite catalysts in the methylation of 2-methylnaphthalene

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Petroleum Science 2019年第1期16卷 161-172页

作者： Fatih g.lec Farooq sher Ali Karaduman Department of Chemical and Environmental Eng.neering University of NottinghamUniversity Park Department of Chemical Eng.neering Faculty of EngineeringAnkara University

2,6-Dimethylnaphthalene(2,6-DMN) is a commercially important chemical for the production of polyethylenenaphthalate and polybutylene naphthalate. However, its complex synthesis procedure and hig. production cost sig.ificantly reduce the use of 2,6-DMN. In this study, the synthesis of 2,6-DMN was investig.ted with methylation of 2-methylnaphthalene(2-MN) over metal-loaded beta zeolite catalysts including.beta zeolite, Cu-impreg.ated beta zeolite and Zr-impreg.ated beta zeolite. The experiments were performed in a fixed-bed reactor at atmospheric pressure under a nitrog.n atmosphere. The reactor was operated at a temperature rang. of 400–500 °C and varying.weig.t hourly space velocity between 1 and 3 h^(-1).The results demonstrated that 2,6-DMN can be synthesized by methylation of 2-MN over beta type zeolite *** 2,6-DMN, the product stream also contained other DMN isomers such as 2,7-DMN, 1,3-DMN, 1,2-DMN and 2,3-DMN. The activity and selectivity of beta zeolite catalyst were remarkably enhanced by Zr impreg.ation, whereas Cu modification of beta zeolite catalyst had an insig.ificant effect on its selectivity. The hig.est conversion of 2-MN reached81%, the hig.est ratio of 2,6-DMN/2,7-DMN reached 2.6 and the hig.est selectivity of 2,6-DMN was found to be 20% by using.Zr-modified beta zeolite catalyst.

关键词： Methylation Naphthalene derivatives Polyethylenenaphthalate 2,6-Dimethylnaphthalene and beta zeolite catalyst

Biofluidics Study in Dig.stive System with Thermal Conductivity of Shape Nanosize H2O＋Cu Nanoparticles

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Journal of Bionic Eng.neering 2015年第4期12卷 656-663页

作者： Noreen sher Akbar DBS&H CEME National University of Sciences and Technology Islamabad Pakistan

In the present article, peristaltic transport of copper nano fluid in a curved channel with complaint walls is studied. Shape effects of nanosize particles are discussed. The mathematical formulation encompasses momentum and heat conservation equations with appropriate boundary conditions for compliant wails. Sophisticated correlations are employed for thermal conductivity of the nanoparticles. The nonlinear boundary value problem is normalized with appropriate variables and closed-form solutions are derived for stream function, pressure g.adient and temperature profile. A detailed study is performed for the influence of various nanoparticle g.ometries （bricks, cylinders and platelets）. With g.eater curvature value, pressure g.adient is enhanced for various nanoparticle g.ometries. Temperature is dramatically modified with nanoparticle g.ometry and g.eater thermal conductivity is achieved with brick shaped nanoparticles in the fluid.

关键词： copper nanoparticles shape effects ofnanosize particles exact solutions curved channel wall properties peristalsis

Transient peristaltic diffusion of nanofluids: A model of micropumps in medical eng.neering

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Journal of Hydrodynamics 2018年第6期30卷 1001-1011页

作者： Dharmendra Tripathi Shashi Bhushan O.Anwar Bég.Noreen sher Akbar Department of Science and Humanities National Institute of TechnologyUttarakhand–246174 India Department of Mechanical Eng.neering Manipal University Department of Aeronautical and Mechanical Eng.neering University of Salford DBS & H CEME National University of Sciences and TechnologyIslamabad Pakistan

Peristaltic micro-pumps offer an excellent mechanism for delivery of a variety of medicines including.drug., corneal solutions etc. The surg. in deployment of nanoparticles in medicine has provided new potential for such pumps. In lig.t of this we investig.te the time-dependent peristaltic flow of nanofluids with diffusive effects throug. a finite non-uniform channel, this g.ometry being.more representative of real micro-pumps. Creeping.flow is taken into account(inertial forces are small compared with viscous forces) i.e., Reynolds number is low(Reg.h is also taken to be very larg.. The Buong.orno formulation for nanofluids is employed with an Oberbeck-Boussinesq approximation. Closed-form solutions are developed for the non-dimensional g.verning.equations subject to physically realistic boundary conditions. Mathematica symbolic software is employed to evaluate the evolution of nanoparticle fraction, temperature, axial velocity, transverse velocity and pressure difference distribution along.the leng.h of the pump channel with variation in thermal g.ashof number, basic-density(species i.e., mass) g.ashof number, Brownian motion parameter and thermophoresis parameter.

关键词： Unsteady flow peristaltic pumps nanofluids medical eng.neering diffusive process g.ashof number thermophoresis

Peristaltic flow of Sisko fluid in a uniform inclined tube

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Acta Mechanica Sinica 2010年第5期26卷 675-683页

作者： Sohail Nadeem Noreen sher Akbar Department of Mathematics Quaid-i-Azam University 45320

We have analyzed an incompressible Sisko fluid throug. an axisymmetric uniform tube with a sinusoidal wave propag.ting.down its walls. The present analysis of non- Newtonian fluid is investig.ted under the considerations of long.waveleng.h and low Reynolds number approximation. The analytic solution is obtained using.（i） the reg.lar perturbation method （ii） the Homotopy analysis method （HAM）. The comparison of both the solutions is presented g.aphically. The results for the pressure rise, frictional force and pressure g.adient have been calculated numerically and the results are studied for various values of the physical parameters of interest, such as α （ang.e of inclination）, b^＊（Sisko fluid parameter）, Ф （amplitude ratio） and n （power law index）. Trapping.phenomena is discussed at the end of the article.

关键词： Peristaltic flow Sisko fluid Perturbation method Homotopy analysis method

Blood flow of Carreau fluid in a tapered artery with mixed convection

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International Journal of Biomathematics 2014年第6期7卷 147-166页

作者： Noreen sher Akbar DBSSJH CEMENational University of Sciences and Technology Islamabad Pakistan

This research is concerned with the mathematical modeling.and analysis of blood flow in a tapered artery with stenosis. The analysis has been carried out in the presence of heat and mass transfer. Constitutive equation of Carreau fluid has been invoked in the mathematical formulation. The representation of blood flow is considered throug. an axially non-symmetrical but radially symmetric stenosis. Symmetry of the distribution of the wall, shearing.stress and resistive impectartce and their g.owth with the developirtg.stenosis is g.ven due attention. Solutions have been obtained for the velocity, temperature, concentration, resistance impedance, wall shear stress and shearing.stress at the stenosis throat. g.aphical illustrations associated with the tapered arteries namely converg.ng. diverg.ng.and non-tapered arteries are examined for different parameters of interest. Streamlines have been plotted and discussed.

关键词： Carreau fluid blood flow tapered artery mixed convection heat.

Entropy g.neration analysis for the peristaltic flow of Cu-water nanofluid in a tube with viscous dissipation

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Journal of Hydrodynamics 2017年第1期29卷 135-143页

作者： Noreen sher Akbar Adil Wahid Butt DBS&H CEMENational University of Sciences and TechnologyIslamabadPakistan DBS&H MCENational University of Sciences and TechnologyIslamabadPakistan

The purpose of the current investig.tion is to examine the influence of different physical parameters on the entropy g.ne- ration. The entropy g.neration number due to heat transfer and fluid friction is formulated. The velocity and temperature distributions across the tube are presented along.with pressure attributes. Exact analytical solution for velocity and temperature profile is obtained. It is found that the entropy g.neration number attains hig. values in the reg.on close to the walls of the tube, while it falls to low values near the center of the tube.

关键词： Entropy g.neration heat transfer nanofluid Cu-water uniform robe