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Topological effects on non-relativistic eigenvalue solutions under AB-flux field with pseudoharmonic- and Mie-type potentials

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Communications in Theoretical Physics 2023年第5期75卷 84-96页

作者： Faizuddin ahmed Department of Physics University of Science&Technology MeghalayaRi-BhoiMeghalaya-793101India

In this paper,we investigate the quantum dynamics of a non-relativistic particle confined by the Aharonov-Bohm quantum flux field with pseudoharmonic-type potential in the background of topological defect produced by a point-like global *** solve the radial Schrödinger equation analytically and determine the exact eigenvalue solution of the quantum ***,we consider a Mie-type potential in the quantum system and solve the radial equation analytically and obtain the eigenvalue *** analyze the effects of the topological defect and the quantum flux with these potentials on the energy eigenvalue and wave function of the nonrelativistic *** fact,it is shown that the energy levels and wave functions are influenced by the topological defect shifted the result compared to the flat space *** addition,the quantum flux field also shifted the eigenvalue solutions and an analogue of the Aharonov-Bohm effect for bound-states is ***,we utilize these eigenvalue solutions to some known diatomic molecular potential models and presented the energy eigenvalue and wave function.

关键词： topological defect non-relativistic wave equation physical potential geometric quantum phase special function solutions of wave equation:bound-state

Conservation Laws for Partially Conservative Variable Mass Systems via d＇Alembert＇s Principle

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Chinese Physics Letters 2008年第9期25卷 3181-3184页

作者： AFTAB ahmed NASEER ahmed QUDRAT Khan Department of Mathematics Quaid-I-Azam University 45320 Islamabad 44000 Pakistan

Conservation laws for partially conservative variable mass dynamical systems under symmetric infinitesimal transformations are determined. A generalization of Lagrange-d ＇Alembert＇s principle for a variable mass system in terms of asynchronous virtual variation is presented. The generalized Killing equations are obtained such that their solution yields the transformations and the associated conservation laws. An example illusstrative of the theory is furnished at the end as well.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Boundary layer flow of Maxwell fluid due to torsional motion of cylinder: modeling and simulation

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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 667-680页

作者： M.KHAN A.ahmed J.ahmed Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

This paper investigates the boundary layer flow of the Maxwell fluid around a stretchable horizontal rotating cylinder under the influence of a transverse magnetic *** constitutive flow equations for the current physical problem are modeled and analyzed for the first time in the *** torsional motion of the cylinder is considered with the constant azimuthal velocity *** partial differential equations(PDEs)governing the torsional motion of the Maxwell fluid together with energy transport are simplified with the boundary layer *** current analysis is valid only for a certain range of the positive Reynolds ***,for very large Reynolds numbers,the flow becomes ***,the governing similarity equations are simplified through suitable transformations for the analysis of the large Reynolds *** numerical simulations for the flow,heat,and mass transport phenomena are carried out in view of the bvp4c scheme in *** outcomes reveal that the velocity decays exponentially faster and reduces for higher values of the Reynolds numbers and the flow penetrates shallower into the free stream *** is also noted that the phenomenon of stress relaxation,described by the Deborah number,causes to decline the flow fields and enhance the thermal and solutal energy transport during the fluid *** penetration depth decreases for the transport of heat and mass in the fluid with the higher Reynolds *** excellent validation of the numerical results is assured through tabular data with the existing literature.

关键词： torsional motion Maxwell fluid magnetic field stretchable rotating cylinder bvp4c scheme

Reviving the use of inhibitors of matrix metalloproteases in spinal cord injury:a case for specificity

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Neural Regeneration Research 2023年第9期18卷 1925-1930页

作者： Zubair ahmed Neuroscience and Ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Center for Trauma Sciences Research University of BimringhamEdgbastonBirminghamUK

At present,there are no resto rative therapies in the clinic for spinal cord injury,with current treatments offering only palliative treatment *** role of matrix metalloproteases is well established in spinal cord injury,howeve r,translation into the clinical space was plagued by early designs of matrix metalloprotease inhibitors that lacked specificity and fears of musculos keletal syndrome prevented their further *** r,much more specific matrix metalloprotease inhibitors have revived the possibility of using these inhibitors in the clinic since they are much more specific to their to rget matrix ***,the evidence for use of matrix metalloproteases after spinal cord injury is reviewed and researche rs are urged to overcome their old fears rega rding matrix metalloprotease inhibition and possible side effects for the field to *** published work by us shows that inhibition of specific matrix metalloproteases after spinal cord injury holds promise since four key consequences of spinal cord injury could be alleviated by specific,next-gene ration matrix metalloprotease *** example,specific inhibition of matrix metalloprotease-9 and matrix metalloprotease-12 within 24 hours after injury and for 3 days,alleviates spinal cord injury-induced edema,blood-s pinal co rd barrier breakdown,neuro pathic pain and resto res sensory and locomotor *** are now underway to translate this therapy into the clinic.

关键词： axon regeneration blood-spinal cord barrier edema functional recovery matrix metalloprotease-9 matrix metalloproteses-12 pain spinal cord injury

Klein–Gordon oscillator with magnetic and quantum flux fields in non-trivial topological space-time

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Communications in Theoretical Physics 2023年第2期75卷 89-97页

作者： Faizuddin ahmed Department of Physics University of Science&Technology MeghalayaRi-BhoiMeghalaya—793101India

The relativistic quantum motions of the oscillator field(via the Klein–Gordon oscillator equation)under a uniform magnetic field in a topologically non-trivial space-time geometry are *** solve the Klein–Gordon oscillator equation using the Nikiforov-Uvarov method and obtain the energy profile and the wave *** discuss the effects of the non-trivial topology and the magnetic field on the energy *** find that the energy eigenvalues depend on the quantum flux field that shows an analogue of the Aharonov–Bohm ***,we obtain the persistent currents,the magnetization,and the magnetic susceptibility at zero temperature in the quantum system defined in a state and show that these magnetic parameters are modified by various factors.

关键词： relativistic wave equations -solutions of wave equations:bound-state geometric quantum phases magnetic fields

Transient flow of magnetized Maxwell nanofluid: Buongiorno model perspective of Cattaneo-Christov theory

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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 655-666页

作者： M.KHAN A.ahmed J.ahmed Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

The present research article is devoted to studying the characteristics of Cattaneo-Christov heat and mass fluxes in the Maxwell nanofluid flow caused by a stretching sheet with the magnetic field *** Maxwell nanofluid is investigated with the impact of the Lorentz force to examine the consequence of a magnetic field on the flow characteristics and the transport of *** heat and mass transport mechanisms in the current physical model are analyzed with the modified versions of Fourier’s and Fick’s laws,***,the well-known Buongiorno model for the nanofluids is first introduced together with the Cattaneo-Christov heat and mass fluxes during the transient motion of the Maxwell *** governing partial differential equations(PDEs)for the flow and energy transport phenomena are obtained by using the Maxwell model and the Cattaneo-Christov theory in addition to the laws of *** transformations are used to convert the PDEs into a system of nonlinear ordinary differential equations(ODEs).The homotopic solution methodology is applied to the nonlinear differential system for an analytic *** results for the time relaxation parameter in the flow,thermal energy,and mass transport equations are discussed *** is noted that higher values of the thermal and solutal relaxation time parameters in the Cattaneo-Christov heat and mass fluxes decline the thermal and concentration fields of the ***,larger values of the thermophoretic force enhance the heat and mass transport in the ***,the Brownian motion of the nanoparticles declines the concentration field and increases the temperature *** validation of the results is assured with the help of numerical tabular data for the surface velocity gradient.

关键词： transient flow Cattaneo-Christov theory Maxwell nanofluid Buongiorno model homotopy analysis method (HAM) solution

Thermal analysis in swirl motion of Maxwell nanofluid over a rotating circular cylinder

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Applied Mathematics and Mechanics(English Edition) 2020年第9期41卷 1417-1430页

作者： A.ahmed M.KHAN J.ahmed Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

In this paper,the mechanism of thermal energy transport in swirling flow of the Maxwell nanofluid induced by a stretchable rotating cylinder is *** rotation of the cylinder is kept constant in order to avoid the induced axially secondary ***,the novel features of heat generation/absorption,thermal radiation,and Joule heating are studied to control the rate of heat *** effects of Brownian and thermophoretic forces exerted by the Maxwell nanofluid to the transport of thermal energy are investigated by utilizing an effective model for the nanofluid proposed by *** whole physical problem of fluid flow and thermal energy transport is modelled in the form of partial differential equations(PDEs)and transformed into nonlinear ordinary differential equations(ODEs)with the help of the suitable flow *** acquired results through the technique bvp4c are reported graphically with physical *** analysis reveals that there is higher transport of heat energy in the Maxwell nanoliquid for a constant wall temperature(CWT)as compared with the prescribed surface temperature(PST).Both thermophoretic and Brownian forces enhance the thermal energy transport in the flowing Maxwell ***,the temperature distribution increases with increasing values of the radiation parameter and the Eckert *** is also noted that an increase in Reynolds number reduces the penetration depth,and as a result the flow and transport of energy occur only near the surface of the cylinder.

关键词： Maxwell nanofluid rotating cylinder heat source/sink Joule heating convective condition numerical solution

Aharonov-Bohm effect for bound states on spin-0 massive charged particles in a Gödel-type space-time with Coulomb potential

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Communications in Theoretical Physics 2020年第7期72卷 36-41页

作者： Faizuddin ahmed Ajmal College of Arts and Science Dhubri-783324AssamIndia

In this paper,we investigate the relativistic quantum dynamics of spin-0 massive charged particles in a G?del-type space-time with electromagnetic *** derive the radial wave equation of the Klein-Gordon equation with an internal magnetic flux field and Coulombtype potential in the Som-Raychaudhuri space-time with cosmic *** solve this equation and analyze the analog effect in relation to the Aharonov-Bohm effect for bound states.

关键词： Göodel-type metrics relativistic wave equations bound states electromagnetic potential energy spectrum wave-functions

Dry face milling of titanium alloys

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Journal of University of Science and Technology Beijing 2004年第6期11卷 545-548页

作者： ahmed Hassan Manufacturing and Automation Department

In machining titanium alloys, cutting tools generally wear out very rapidlybecause of the high cutting temperature resulted from the low thermal conductivity and density ofthe work material. In order to increase the tool life, it is necessary to suppress the cutting heatas much as possible by applying an abundant amount of coolant, but this will entail serioustechno-environmental and biological problems. To study the performance and avoid these limitations,a PVD-coated insert was used to the dry face mill of (alpha + beta) titanium alloys. As a result itwas found that the inserts exhibit an excellent cutting performance at low cutting speeds and feedrates, and there is no significant difference in the dominant insert failure mode between the wetand dry cutting in discontinuous cutting.

关键词： carbide tool face milling titanium alloy