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Transport of Jeffrey fluid in a rectangular slit of the microchannel under the effect of uniform reabsorption and a porous medium

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Communications in Theoretical Physics 2021年第11期73卷 31-46页

作者： h Mehboob K Maqbool r Ellahi Sadiq M Sait Department of Mathematics and Statistics International Islamic UniversityIslamabadPakistan Center for Modeling&Computer Simulation Research InstituteKing Fahd University of Petroleum&MineralsDhahran-31261Saudi Arabia Fulbright Fellow Department of Mechanical EngineeringUniversity of California RiversideUnited States of America Centre for Communications and IT research Research InstituteKing Fahd University of Petroleum&MineralsDhahran-31261Saudi Arabia

This research explores the transport of a Jeffrey fluid through a permeable slit of microchannel under the effect of a porous medium and constant *** laws of fluid mechanics are used to study the flow in a cross-sectional area of a narrow slit which generates a highly nonlinear system of partial differential equation with nonhomogeneous boundary *** solve the complex boundary value problem;a recursive(Langlois)approach is used and explicit expressions for velocity,pressure,stream function,flux,shear stress and fractional reabsorption are *** is noticed that the flow rate at the centre line of slit and shear stress on the walls of slit decay due to the presence of porous medium and viscoelastic fluid *** is also quantitatively observed that more pressure is required for the fluid flow when the slit is filled with a porous medium and reabsorption on the walls is *** mathematical results of the present research have significant importance in the field of biofluid mechanics and medical industry,therefore the application of a diseased rat kidney is also included in this research:and reabsorption velocities in the case of a diseased and a healthy rat kidney are calculated with the effects of a porous medium and constant re-absorption.

关键词： creeping flow Jeffrey fluid uniform re-absorption porous medium permeable slit micro channel Langlois approach

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A new approach for modelling the damped helmholtz oscillator:applications to plasma physics and electronic circuits

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Communications in Theoretical Physics 2021年第3期73卷 119-130页

作者： S A El-Tantawy Alvaro h Salas M r Alharthi Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt research Center for Physics(rCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia Department of Mathematics Universidad National de ColombiaUniversidad National de Colombia-Nubia Campus Derpartment of Mathematics and Statistics FIZMAKO Research GroupColombia Department of Mathematics and Statistics College of ScienceTaif UniversityPO Box 11099Taif 21944Saudi Arabia

In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear helmholtz equation(hE)in terms of the Weiersrtrass elliptic *** exact solution for undamped hE(integrable case)and approximate/semi-analytical solution to the damped hE(non-integrable case)are given for any arbitrary initial *** a special case,the necessary and sufficient condition for the integrability of the damped hE using an elementary approach is *** general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic *** addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in ***,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two ***,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be *** real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in rLC series circuits and in various plasma models such as electronegative complex plasma model.

关键词： damped and undamped helmholtz equation Korteweg-de Vries type equation plasma oscillations nonlinear rLC circuits Weierstrass ellliptic function periodical solution

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Energy conditions of the f(T,B) gravity dark energy model with the validity of thermodynamics

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Communications in Theoretical Physics 2020年第8期72卷 109-118页

作者： S h Shekh V r Chirde P K Sahoo Department of Mathematics S.P.M.Science and Gilani Arts and Commerce CollegeGhatanjiYavatmalMaharashtra-445301India Department of Mathematics G.S.G.MahavidyalayaUmarkhed-445206India Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In this article, the analysis of Tsallis holographic dark energy(which turns into holographic dark energy for a particular choice of positive non-additivity parameter δ) in modified f(T, B) gravity with the validity of thermodynamics and energy conditions for a homogeneous and isotropic FLrW Universe has been studied. The enlightenment of the field equation towards f(T,B)=αT^m+βB^n, made possible by the fact that the model is purely accelerating,corresponds to q=-0.54(Mamon and Das 2017 Eur. Phys.J.C 77 49). The generalized second law of thermodynamics is valid not only for the same temperature inside the horizon, but also for the apparent horizon for a change in temperature. The essential inspiration driving this article is to exhibit the applicability that the holographic dark energy achieved from standard Tsallis holographic dark energy and the components acquired from f(T, B) gravity are identical for the specific bounty of constants. The analysis of energy conditions confirms that the weak energy condition and the null energy condition are fulfilled throughout the expansion, while violation of the strong energy condition validates the accelerated expansion of the *** the expansion, the model becomes a quintessence dominated model. The dominant energy condition is not observed initially when the model is filled with genuine baryonic matter,whereas it appears when the model is in the quintessence dominated era.

关键词： Tsallis holographic dark energy f(T B)gravity energy conditions thermodynamics

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Microstructural and mechanical characteristics of Al-alloyed ductile iron upon casting and annealing

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 812-820页

作者： N. haghdadi B. Bazaz h.r. Erfanian-Naziftoosi A.r. Kiani-rashid Department of Materials Engineering Faculty of Engineering Ferdowsi University of Mashhad 91775-111 Mashhad Iran School of Metallurgy and Materials Engineering College of Engineering University of Tehran 11365-4563 Tehran Iran

Ductile iron containing 6.16wt% A1 was developed to investigate the effects of aluminum on both its microstructure and hardness. It was found that aluminum not only increases the nodule count and pearlite content but also improves the hardness in both sand mold and metal mold castings. Annealing treatments were conducted to attain a homogenous microstructure and improve high-temperature serviceabil- ity. A ferrite/carbide or ferritic matrix was gained depending on the annealing temperature. It is also discovered that annealing has inverse in- fluences on the hardness of the bulk alloy and the ferrite phase. Although it causes a small decrease in the bulk hardness of the specimens, it leads to an increase in the microhardness of the ferrite. Micro-segregation of the alloying elements was also investigated by means of electron probe micro-analysis for the specimens with different annealing durations and the as-cast specimen as well. An optimum annealing time was proposed to result in the least amount of micro-segregation of aluminum and silicon between graphite nodules.

关键词： cast iron casting annealing microstructure hardness

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A strategy for designing stable nanocrystalline alloys by thermo-kinetic synergy

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Journal of Materials Science & Technology 2020年第8期36卷 21-31页

作者： h.r.Peng B.S Liu F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Analytical and Testing Center Northwestern Polytechnical UniversityXi’an710072China

Aiming to design stable nanocrystalline(NC)materials,so far,it has been proposed to construct nanostructure stability maps in terms of thermodynamic parameters,while kinetic stabilization has seldom been considered,despite the synergy of thermodynamics and ***,the thermodynamically stabilized NC materials may be easily subjected to grain growth at high temperatures due to the weakly kinetic *** from the thermo-kinetic synergy,a stabilization criterion is proposed as a function of intrinsic solute parameters(*** activation energy for bulk diffusion and the segregation enthalpy),intrinsic solvent parameters(*** intrinsic activation energy for GB migration and the GB energy)and processing parameters(*** grain size,the temperature and the solute concentration).Using first-principles calculations for a series of combinations between fifty-one substitutional alloying atoms as solute atoms and Fe atom as fixed solvent atom,it is shown that the thermal stability neither simply increases with increasing the segregation enthalpy as expected by thermodynamic stabilization,nor monotonically increases with increasing the activation energy for bulk diffusion as described by kinetic *** combination of thermodynamic and kinetic contributions,the current stabilization criterion evaluates quantitatively the thermal stability,thus permitting convenient comparisons among NC materials involved by various combinations of the solute atoms,the solvent atoms,or the processing *** of this thermo-kinetic stabilization criterion has been tested by current experiment results of Fe-Y alloy and previously published data of Fe-Ni,Fe-Cr,Fe-Zr and Fe-Ag alloys,etc.,which opens a new window for designing NC materials with sufficiently high thermal stability and sufficiently small grain size.

关键词： Thermo-kinetic Synergy Criterion Thermal stability Nanocrystalline materials

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Effect of Quantum Interference from Incoherent Pumping Field and Spontaneous Emission on Controlling the Optical Bistability and Multi-Stability

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Communications in Theoretical Physics 2013年第2期59卷 199-204页

作者： h.r. hamedi Ali Sari M. Sahrai S.h. Asadpour research Institute for Applied Physics and Astronomy University of Tabriz Department of Electrical Engineering Islamic Azad University Young researchers Club Islamic Azad University

Optical bistability （0t3） and optical multi-stability （OM） of a four-level A-type atomic system with two fold lower levels inside a unidirectional ring cavity is investigated. The effect of quantum interference arising from spontaneous emission and incoherent pumping on 013 and OM is discussed. It is found that the threshold of OB and OM can be controlled by quantum interference mechanisms. In addition intensity of coupling field and the rate of an incoherent pumping field on behavior of OB and OM are then discussed.

关键词： optical bistability optical multistability quantum interference incoherent pumping

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rice (Oryza sativa L.) nutrient management using mycorrhizal fungi and endophytic herbaspirillum seropedicae

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Journal of Integrative Agriculture 2016年第6期15卷 1385-1394页

作者： h hoseinzade M r Ardakani A Shahdi h Asadi rahmani G Noormohammadi M Miransari Department of Agronomy Science and Research Branch Islamic Azad University Tehran *** Iran Department of Agronomy Islamic Azad University Karaj branch 86319615 Iran rice research Institute of Iran Rasht 43114843 Iran Soil and Water research Institute Karaj 394923973 Iran Department of Book&Article Abtin Berkeh L td Company Isfahan *** Iran

Integrated nutrient management with biological and chemical fertilizers can improve rice （Oryza safiva L.） productivity, bio-fortification, soil health and fertility. Accordingly, this study was planned to evaluate the combined effects of biological fertilizers including arbuscular mycorrhizal （AM） fungi （Glomus mosseae） and free-living nitrogen-fixing bacteria （herbaspi- rillum seropedicae）, as well as chemical fertilizers on the yield and nutrient contents of wetland rice under field conditions. Seedlings were inoculated with AM fungi and the bacteria in the nursery and were then transplanted to the field. The experi- ment was carried out as a split factorial design with three replicates. Treatments included three rates of nitrogen （N 1, N2 and N3） and phosphorous （P1, P2 and P3） fertilizers （100, 75 and 50% of the optimum level） in the main plots and mycorrhizal and bacterial treatments in the sub plots. The total of urea （g） used per plot was equal to N1=200, N2=150 and N3=100 at three different growth stages （seeding, tillering and heading） and the total of P （g） per plot used once at seeding using triple super phosphate including P1 =16, P2=13 and P3=10. Plant growth and yield as well as the concentration of nitrogen （N）, phosphorous （P）, potassium （K）, iron （Fe）, and zinc （Zn） were measured in the soil, straw and grains. N-fertilizer and biological fertilizers had significant effects on root, shoot and grain yield of rice, however, P-fertilizer just significantly affected root and shoot dry weights. Interestingly, analyses of variance indicated that biological fertilization significantly affected all the experimental treatments except straw N. AM fungi, N1 and P1 resulted in the highest rate of rice growth and yield. The interactions of chemical and biological fertilization resulted in significant effects on grain Zn, Fe, P, and N as well as soil Fe, K and N. The highest rate of grain nutrient uptake was resulted by the combined use of biological fertilizatio

关键词： bio-fortification nutrient management yield biological fertilizer rice (Oryza sativa L.)

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Intra-and inter-clonal tree growth variations of hevea brasiliensis

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Journal of Forestry research 2012年第3期23卷 429-434页

作者： h.r.Naji M.h.Sahri Department of Forest Production Faculty of ForestryUniversiti Putra MalaysiaSelangor43400Malaysia Department of Forestry Faculty of AgricultureIlam UniversityIlam69315-516Iran

We evaluated the effects of planting densities （500, 1,000, 1,500 and 2,000 ***-1） on tree growth performance （diameter at base, diameter at breast height, and clear bole height） of two clones （rrIM 2020 and PrIM 2025） of nine years old plantations of rubber tree （hevea brasiliensis Muell. Arg） in Malaysia. For the four planting densities of the two clones, basal area and diameter at breast height declined with increasing planting density. Clear bole heights were greatest at 1,500 *** lowest at 500 ***-1 for the clone rrIM 2020, and at 2,000 ***-1and 500 *** clone rrIM 2025. We conclude that the ideal planting density is 2,000 ***＂l for obtaining high volume of wood production and 500 trees-ha-1 for high wood quality.

关键词： clone planting density tree growth hevea brasiliensis

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In-situ measurement of the surface temperature during holographic recording

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Chinese Optics Letters 2008年第1期6卷 25-28页

作者： A.Draude r.Meinhardt h.Franke Y.Zhao r.A.Lessard Department of Physics/Applied Physics University of Duisburg-Essen Département de chimie Universitéde SherbrookeSherbrookeQuébec COPL Département de physiquegénie physique et optiqueUniversité LavalQuébec

Photo-induced processes in organic materials mostly occur on molecular levels. Excited molecules may split to form radicals, starting a polymerization process with diffusing monomers. The azo-dyes perform an optically induced cis-trans isomerization. During pattern formation like a holographic grating, the local temperature increase, especially in thin films, is up to date a subject of estimation from absorption and dissipation data. however, the exact knowledge of the surface temperature would help a lot in understanding the resulting refractive index and thickness patterns during holographic exposure. In this paper, in-situ pyrometer measurements are presented. As examples, different photosensitive materials, varying from a photopolymer to polycrystalline azo dyes, are used in order to outline the magnitude of this effect and demonstrate the feasibility of this technique.

关键词： holographic gratings holographic recording Photosensitive materials refractive index Surface measurements Thin films

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Power transmission through double-walled laminated composite panels considering porous layer-air gap insulation

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Applied Mathematics and Mechanics(English Edition) 2014年第11期35卷 1447-1466页

作者： M.h.ShOJAEIFArD r.TALEBITOOTI B.rANJBAr r.AhMADI School of Mechanical Engineering Iran University of Science & Technology School of Automotive Engineering Iran University of Science & Technology

The acoustic behavior of double-walled laminated composite panels consisting of two porous and air gap middle layers is studied within the classical laminated plate theory （CLPT）. Thus, viscous and inertia coupling in a dynamic equation, as well as stress transfer, thermal and elastic coupling of porous material ave based on the Biot theory. In addition, the wave equations are extracted according to the vibration equation of composite layers. The transmission loss （TL） of the structure is then calculated by solving these equations simultaneously. Statistical energy analysis （SEA） is developed to divide the structure into specific subsystems, and power transmission is extracted with balancing power flow equations of the subsystems. Comparison between the present work and the results reported elsewhere shows excellent agreement. The results also indicate that, although favorable enhancement is seen in noise control particularly at high frequencies, the corresponding parameters associated with fluid phase and solid phase of the porous layer are important on TL according to the boundary condition interfaces. Finally, the influence of composite material and stacking sequence on power transmission is discussed.

关键词： laminated composite plate double panel sound transmission loss porousmaterial statistical energy analysis (SEA)

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