检索结果-南通市图书馆

Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de biología molecular Severo Ochoa(Cbm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： latin potential lasting

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2023年第4期44卷 653-668页

作者： b.J.GIREESHA m.l.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current *** periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer *** modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDm).The results are displayed through graphs and *** effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are *** is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against *** analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

A theoretical investigation of the band alignment of type-I direct band gap dilute nitride phosphide alloy of GaN_xAs_yP_(1-x-y)/GaP quantum wells on GaP substrates

在线全文

学校读者我要写书评

暂无评论

Chinese Physics b 2014年第7期23卷 640-644页

作者： O l nsal b Gnül m Temiz Department of Engineering Physics University of Gaziantep

The GaP-based dilute nitride direct band gap material Ga（NAsP） is gaining importance due to the monolithic integra- tion of laser diodes on Si microprocessors. The major advantage of this newly proposed laser material system is the small lattice mismatch between GaP and Si. However, the large threshold current density of these promising laser diodes on Si substrates shows that the carrier leakage plays an important role in Ga（NAsP）/GaP QW lasers. Therefore, it is necessary to investigate the band alignment in this laser material system. In this paper, we present a theoretical investigation to optimize the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs on GaP substrates. We examine the effect of nitrogen （N） concentration on the band offset ratios and band offset energies. We also provide a comparison of the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs with that of the GaNxAsyP1-x-y/Al2Ga1-2P QWs on GaP substrates. Our theoretical calculations indicate that the incorporations of N into the well and AI into the barrier improve the band alignment compared to that of the GaAsP/GaP QW laser heterostructures.

关键词： quantum well band alignment carrier confinement dilute nitride phosphide alloy

A Search on Dirac Equation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics letters 2007年第11期24卷 3024-3027页

作者： m. Kocak, b. Gonül Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

The solutions, in terms of orthogonal polynomials, of Dirac equation with analytically solvable potentials are investigated within a novel formalism by transforming the relativistic equation into a Schrodinger-like one. Earlier results are discussed in a unified framework, and some solutions of a large class of potentials are given.

关键词： coated conductor buffer layer self-epitaxy CeO2

Remarks on Exact Solvab.lity of Quantum Systems with Spatially Varying Effective mass

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics letters 2005年第11期22卷 2742-2745页

作者： b. Goenül m. Kocak Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.

关键词： DEPENDENT EFFECTIVE mASSES SUPERSYmmETRIC APPROACH SCHRODINGER-EQUATION PERTURbATION-THEORY POTENTIAlS SEmICONDUCTORS STATES

The C–V and G/ω–V Electrical Characteristics of ^(60)Co γ-Ray Irradiated Al/Si_(3)N_(4)/p-Si (mIS) Structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics letters 2013年第7期30卷 193-197页

作者： S.Zeyrek A.Turan m.m.b.lb.l Department of Physics Faculty of Arts and SciencesDumlupınar University43100KütahyaTurkey Department of Physics Faculty of SciencesGazi University06500BeşevlerAnkaraTurkey

The influence of ^(60)Co(γ-ray)irradiation on the electrical characteristics of Al/Si_(3)N_(4)/p-Si(mIS)structures is investigated using capacitance-voltage(C–V)and conductance-voltage(G/ω–V)*** mIS structures are exposed to a ^(60)Coγradiation source at a dose of 0.7 kGy/h,with a total dose range of 0–100 *** C–V and G/ω–V properties are measured before and after ^(60)Coγ-ray irradiation at 500 kHz and room *** is found that the capacitance and conductance values decrease with the increase in the total dose due to the irradiation-induced defects at the *** results also indicate thatγradiation causes an increase in the barrier height Фb,Fermi energy EF and depletion layer width W_(D).The interface state density(N_(ss)),using the Hill–Coleman method and dependent on radiation dose,is determined from the C–V and G/ω–V measurements and decreases with an increase in the radiation *** decrease in the interface states can be attributed to the decrease in the recombination centers and the passivation of the Si surface due to the deposition insulator layer(Si_(3)N_(4)).In addition,it is clear that the acceptor concentration NA decreases with increasing radiation *** profile of series resistance Rs for various radiation doses is obtained from forward and reverse-biased C–V and G/ω–V measurements,and its values decrease with increasing radiation dose,while it increases with increasing voltage in the accumulation region.

关键词： capacitance interface attributed

Unsteady generalized Couette flow in composite microchannel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2011年第1期32卷 23-32页

作者： m.l.KAURANGINI b.K.JHA Department of mathematical Sciences Kano University of Science and Technology Department of mathematics Ahmadu Bello University

A numerical study is reported on the fully developed unsteady laminar fluid flow in microchannel parallel-plates partially filled with a uniform porous medium and partially filled with a clear fluid. The flow is induced by the movement of one of the plates and the pressure gradient. The brinkman-extended Darcy model is utilized to model the flow in the porous region, while the Stokes equation is used in the clear fluid region. A theoretical analysis is also presented for the fully developed steady flow to find closed- form expressions for the interracial velocity and the velocity and skin frictions at the bounding plates. Numerical computations shows excellent agreement between the closedform solutions for fully developed steady flow and the numerical solution to unsteady flow at large values of time.

关键词： unsteady flow composite microchannel

Effects of stretching/shrinking on the thermal performance of a fully wetted convective-radiative longitudinal fin of exponential profile

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2022年第3期43卷 389-402页

作者： b.J.GIREESHA m.l.KEERTHI G.SOWmYA Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India Department of PG mathematics The National College(Auto)Bangalore 560070India

The present investigation focuses on the thermal performance of a fully wet stretching/shrinking longitudinal fin of exponential profile coated with a mechanism like a conveyer *** modeled equation is non-dimensionalized and solved by applying the Runge-Kutta-Fehlberg(RKF)*** effects of parameters such as the wet parameter,the fin shape parameter,and the stretching/shrinking parameter on the heat transfer and thermal characteristics of the fin are graphically analyzed and *** is inferred that the negative effects of motion and internal heat generation on the fin heat transfer rate can be lessened by setting a shrinking mechanism on the fin *** current examination is inclined towards practical applications and is beneficial to the design of fins.

关键词： fully wet longitudinal fin convection exponential profile internal heat generation moving fin

Effects of thermophoresis particle deposition and of the thermal conductivity in a porous plate with dissipative heat and mass transfer

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Sinica 2011年第3期27卷 389-398页

作者： Joaquín Zueco O.Anwar bég l.m.lpez-Ochoa Thermal Engineering and Fluids Department Technical University of CartagenaETSII Campus Muralla del Mar Aerospace Engineering Department of Engineering and MathematicsSheaf BuildingSheffield Hallam University mechanical Engineering Departament University of RiojaC/Luís de UlloaLogrono (La Rioja)20E-26004Spain

Network simulation method（NSm） is used to solve the laminar heat and mass transfer of an electricallyconducting,heat generating/absorbing fluid past a perforated horizontal surface in the presence of viscous and Joule heating problem. The governing partial differential equations are non-dimensionalized and transformed into a system of nonlinear ordinary differential similarity equations,in a single independent variable,畏. The resulting coupled,nonlinear equations are solved under appropriate transformed boundary conditions. Computations are performed for a wide range of the governing flow parameters,viz Prandtl number,thermophoretic coeffcient（a function of Knudsen number）,thermal conductivity parameter,wall transpiration parameter and Schmidt number. The numerical details are discussed with relevant applications. The present problem finds applications in optical fiber fabrication,aerosol filter precipitators,particle deposition on hydronautical blades,semiconductor wafer design,thermo-electronics and problems including nuclear reactor safety.

关键词： Thermophoresis . mHD . Network simulation model . Heat and mass transfer- Hartmann number

Dynamic Vehicular Clustering Enhancing Video on Demand Services Over Vehicular Ad-hoc Networks

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2022年第8期72卷 3493-3510页

作者： m.Almutiq l.Sellami b.Alaya Department of management Information Systems and Production management College of Business and EconomicsQassim University6633Buraidah51452Saudi Arabia CONPRI laboratory University of GabesTunisia IResComath laboratory University of GabesTunisia

Nowadays,video streaming applications are becoming one of the tendencies driving vehicular network *** this work,considering the unpredictable vehicle density,the unexpected acceleration or deceleration of the different vehicles included in the vehicular traffic load,and the limited radio range of the employed communication scheme,we introduce the“Dynamic Vehicular Clustering”(DVC)algorithm as a new scheme for video streaming systems over vehicular ad-hoc networks(VANET).The proposed algorithm takes advantage of the small cells concept and the introduction of wireless backhauls,inspired by the different features and the performance of the long Term Evolution(lTE)-Advanced *** are clustered together to form dynamically ad-hoc sub-networks included in the vehicular *** goal of our clustering algorithm is to take into account several characteristics,such as the vehicle’s position and acceleration to reduce latency and packet ***,each cluster is counted as a small cell containing vehicular nodes and an access point that is elected regarding some particular *** on the exceptional features of the lTE-Advanced network(small cells and wireless backhauls)the DVC algorithm is a promising scheme for video streaming services over VANET *** were carried out with a virtual topology of the VANET network created with four clusters to implement the DVC *** results were compared with other algorithms such as Virtual Trust-ab.lity Data transmission(VTD),Named Data Networking(NDN),and Socially Aware Security message Forwarding(SASmF).Our algorithm can effectively improve the transmission rate of data packets at the expense of a slight increase in end-to-end delay and control overhead.

关键词： 5G video-on-demand vehicular ad-hoc network mob.lity vehicular traffic load small cell wireless backhaul lTE-advanced latency packet loss