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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 637-654页

作者： Lijun ZHANG m.b.ARAIN m.m.bHATTI A.ZEESHAN H.HAL-SULAmI College of mathematics and Systems Science Shandong University of Science and Technology Nonlinear Analysis and Applied mathematics (NAAm)-Research Group Department of Mathematics Faculty of Science King Abdulaziz University Department of mathematics and Statistics International Islamic University

The three-dimensional(3D) nano?uid ?ow among the rotating circular plates ?lled with nanoparticles and gyrotactic microorganisms is studied. A generalized form of the magnetic Reynolds number is used for the mathematical modeling of the ferro-nano?uid ?ow. The torque e?ects on the lower and upper plates are calculated.A di?erential transform scheme with the Pad′e approximation is used to solve the coupled highly nonlinear ordinary di?erential equations. The results show that the squeeze Reynolds number signi?cantly suppresses the temperature, microorganism, and nanoparticle concentration distribution, and agree well with those obtained by the numerical method.

关键词： swimming of microorganism generalized magnetic Reynolds number nanofluid differential transform solution circular rotating plate

mETHOD OF mOmENT EXCITATION IN TESTING OF STRUCTURES

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Acta mechanica Solida Sinica 1995年第3期8卷 277-282页

作者： b.m.Gibbs Acoustics Research Unit Liverpool University P.O.Box 147Liver pool L69 3BXU.K.

The method of the moment excitation in the studies of the structure-borne sound using a moment actuator is introduced. Some design considerations for the moment actuator are presented. A standard mechanical system is established to calibrate the performance of the moment actuator. The frequency and mechanical power performances of the actuator are discussed.

关键词： mOmENT ACTUATOR ANALOGOUS CIRCUIT CROSS-SPECTRUm mETHOD

New turbulence modeling for air/water stratified flow

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Journal of Ocean Engineering and Science 2020年第1期5卷 55-67页

作者： m.Ghafari m.b.Ghofrani Department of Energy Engineering Sharif University of TechnologyAzadi Ave.TehranIran

The prediction of interfacial turbulence characteristics is one of the still challenging of two-phase stratified *** evaluation of some important parameters such as interfacial heat transfer coefficient based on turbulence kinetic energy and turbulence dissipation rate in some models,intensifies the importance of turbulence flow correct *** gradient of velocity and turbulence kinetic energy at the interface of two-phase stratified flow leads to a major overestimation or underestimation of flow characteristics without any special *** of a source function of turbulence eddy frequency at the interface is one of the common solution employed in past *** this solution remedies some shortcomings of traditional methods in smooth stratified flow,its application in wavy stratified flow needs the other *** examination of turbulence characteristics near the free surface reveals that,in addition to turbulence eddy frequency,the other source function of turbulence kinetic energy should be considered near the free ***,a new source function of turbulence kinetic energy is proposed at the interface based on flow *** new method has been employed for Fabre et al.(1987)experiment designed for air/water stratified *** results of simulation have a good agreement with experimental data and turbulence characteristic can be captured near the free surface.

关键词： Stratified flow Turbulence model Turbulence kinetic energy Source function

metal-enhanced fluorescence of graphene oxide by palladium nanoparticles in the blue-green part of the spectrum

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Chinese Physics b 2016年第11期25卷 576-583页

作者： A Omidvar m R Rashidian Vaziri b Jaleh N Partovi Shabestari m Noroozi Department of Physics Bu-Ali Sina University Laser and Optics Research School NSTRI Tehran Iran Center for Research and Development of Petroleum Technologies at Kermanshah Research Institute of Petroleum Industry (RIPI)

Graphene oxide（GO） has a wide fluorescence bandwidth,which makes it a prospective candidate for numerous *** many of these applications,the fluorescence yield of GO should be further *** sp2-hybridized carbons in GO confine the π-*** recombination of electron-hole pairs in such sp2 clusters is the source of fluorescence in this *** nanoparticles are good catalysts for sp2 bond *** report on the preparation of GO,palladium nanoparticles and their nanocomposites in two different *** is shown that palladium nanoparticles can considerably enhance the intrinsic fluorescence of GO in the blue-green part of the visible light *** enhancement has been attributed to the catalytic role of palladium nanoparticles in increasing the number of sp2 bonds of GO with the molecules of the surrounding *** is shown that palladium nanoparticles could be the nanoparticle of choice for fluorescence enhancement of GO because of their catalytic role in sp2 bond formation.

关键词： palladium formations considerably bonds Palladium attributed numerous Fluorescence visible bandwidth

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

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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

Design concerns of room and pillar retreat panels

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International Journal of mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted m. Sears morgan m. Tulu Ihsan b. mining Engineer Ground Control branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do some room and pillar retreat panels encounter abnormal conditions？ What factors deserve the most consideration during the planning and execution phases of mining and what can be done to mitigate those abnormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details observations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences observed among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions between primary and secondary support, but produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the obse^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. both the Lamodel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of both models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overburden load. both models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not be overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety multiple seam

Numerical Investigation of the Flow inside the Combustion Chamber of a Plant Oil Stove

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Journal of Thermal Science 2013年第5期22卷 491-496页

作者： b. Pritz m. Werler H. Wirbser m. Gabi Institute of Fluid machinery Karlsruhe Institute of Technology (KIT)Kaiserstr. 12 76131 Karlsruhe Germany Institute of Technical Thermodynamics KITKaiserstr. 12 76131 Karlsruhe Germany

Recently a low cost cooking device for developing and emerging countries was developed at KIT in cooperation with the company bosch und Siemens Hausger^ite GmbH. After constructing an innovative basic design further development was required. Numerical investigations were conducted in order to investigate the flow inside the combustion chamber of the stove under variation of different geometrical parameters. beyond the performance improvement a further reason of the investigations was to rate the effects of manufacturing tolerance problems. In this paper the numerical investigation of a plant oil stove by means of RANS simulation will be presented. In or- der to reduce the computational costs different model reduction steps were necessary. The simulation results of the basic configuration compare very well with experimental measurements and problematic behaviors of the ac- tual stove design could be explained by the investigation.

关键词： plant oil stove cooking device fuel evaporation combustion chamber CFD RANS

Effect of Pearlite Interlamellar Spacing on Predominant Abrasive Wear mechanism of Fully Pearlitic Steel

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材料热处理学报 2004年第05B期25卷 1207-1213页

作者： J. Ahmadi m. monirvaghefi m. Salehi b. Niroumand merat poolad engineering company Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan Iran

The aim of this investigation was the determination of the predominant wear mechanism on three-body abrasion of fully pearlitic low alloy steel. Furthermore, the effect of pearlite interlamellar spacing on wear behavior was investigated. For this purpose, the samples were subjected to the different heat treating to attaining different interlamellar spacing. mechanical properties such as hardness, yield strength, tensile strength, elongation, and impact toughness were evaluated. Three body abrasion tests were conducted under ASTm standard condition using a rubber wheel abrasion test apparatus. Abraded surface and wear debris were investigated by light optical microscopy and scanning electron microscopy. The results showed that wear resistance of fully pearlitic steel depended to pearlite interlamellar spacing the and lower spacing has the greater wear resistance, so it may be due to subsurface work hardening and interlamellar spacing and cementite in fine and/or coarse pearlite, that influence on surface destruction during wear. Although during wear process the several mechanisms play roles, but study of surface and debris shows that with decreasing interlamellar spacing, the predominant mechanism wear changed from ploughing to cutting mode.

关键词：层间距珠光体三体磨损钢

Uniform Query Framework for Relational and NoSQL Databases

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Computer modeling in Engineering & Sciences 2017年第2期113卷 171-181页

作者： J.b.Karanjekar m.b.Chandak Shri Ramdeobaba College of Engineering and management NagpurIndia and Izel Technologies Pvt Ltd.PuneIndia Shri Ramdeobaba College of Engineering and management NagpurIndia

As the data managed by applications has evolved over the years with the arrival of Web 2.0,a large number of new databases have been developed to manage various types of *** the traditional relational databases continue to exist,NoSQL databases which are document oriented or key-value stores or columnar continue to evolve and are embraced very rapidly across the *** is not just the type of data handled by these databases that is different but also the query language they use is also *** paper talks about a uniform query framework that can be used for traditional relational databases and NoSQL *** query framework can also perform joins,aggregates,filter on data from various data sources in a single query.

关键词： NoSQL RDbmS data tetrieval inter-database joins SQL Cassandra mongoDb Calcite mySQL

Simulation of the spatio-temporal evolution of the electron energy distribution function in a pulsed hollow-cathode discharge

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Plasma Science and Technology 2023年第3期25卷 87-94页

作者： N A ASHURbEKOV K O ImINOV K m RAbADANOV G S SHAKHSINOV m Z ZAKARYAEVA m b KURbANGADZHIEVA Dagestan State University Department of Physics Harbin Institute of Technology Institute of Physics Dagestan Federal Research CenterRussian Academy of Sciences

This article presents the 2D simulation results of a nanosecond pulsed hollow cathode discharge obtained through a combination of fluid and kinetic *** spatio-temporal evolution of the electron energy distribution function(EEDF)of the plasma column and electrical characteristics of the nanosecond pulsed hollow cathode discharge at a gas pressure of 5 Torr are *** results show that the discharge development starts with the formation of an ionization front at the anode *** ionization front splits into two parts in the cathode cavity while propagating along its lateral *** ionization front formation leads to an increase in the fast isotropic EEDF component at its front,as well as in the anisotropic EEDF *** accelerated electrons enter the cathode cavity,which significantly contributes to the formation of the highenergy EEDF component and EEDF anisotropy.

关键词： pulsed nanosecond discharge electron energy distribution fuinction hollow cathode electron kinetics gas discharge