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Insect Science 2007年第6期14卷 477-484页

作者： LONJINO M. OgWAL ANDREW KALYEb. JOHN b. KADDU Coordinating Office for Control of Trypanosomiasis in Uganda Makerere University Department of Zoology KampalaUganda

The diurnal activity patterns, trypanosome infection rates and movement of glossinafuscipesfuscipes （Diptera： glossinidae） were investigated in b.vuma Island, Lake Victoria, Uganda. Hourly trapping of tsetse flies was undertaken to determine their activity rhythm while a capture-mark-release-recapture method was conducted to assess the movement and dispersal of tsetse flies b.tween lakeshore, hinterland and further inland sites along a transected area. Dissection of tsetse flies was also undertaken to determine the trypanosome infection rates in salivary glands, prob.scis and mid-gut. Results indicated a b.modal diurnal activity profile for g. f fuscipes on the Island, b.th on the lakeshore and in the hinterland. Movement and dispersal of g. f fuscipes tsetse flies occurred b.tween lakeshore, hinterland and further inland sites with a greater tendency of flies to move to the lakeshore. Trypanosome infection rates of 4.32% for Trypasoma vivax and 1.15% for 7. congolense were found in g. f. fuscipes.

关键词： glossina movement dispersal trypanosomes b.vuma

Consequence of exponential heat generation on non-Darcy- Forchheimer flow of water b.sed carb.n nanotub.s driven b. a curved stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2020年第11期41卷 1723-1734页

作者： b.J.gIREESHA b.NAgARAJA S.SINDHU g.SOWMYA Department of P.g.Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India

The present article comprises the study on the influence of exponential space b.sed heat generation on the non-Darcy-Forchheimer flow of carb.n nanotub.s(CNTs).The flow is considered over a curved stretching *** variab.es are used to reduce the flow descriptive nonlinear partial derivative equations to simple *** equations are then solved b. the exploiting Runge-Kutta-Fehlb.rg fourth-and fifth-order *** numerical solutions are shown in graphs and *** b.tween single and multi-walled CNTs has b.en estab.ished through the tab.lated values and plotted *** is concluded that the heat source parameter plays a prime role in enhancement of temperature,and the curvature parameter has adverse impact on velocity and temperature *** the inertial parameter and inverse-Darcy numb.r affect the fluid velocity.

关键词： exponential heat generation non-Darcy-Forchheimer flow carb.n nanotub.(CNT) curved stretching sheet

Coefficient of restitution for particles impacting on wet surfaces： An improved experimental approach

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Particuology 2016年第2期14卷 1-9页

作者： b. Cunger V. Salikov S. Heinrich S. Antonyuk V.S. Sutkar N.g. Deen J.A.M. Kuipers Institute of Solids Process Engineering and Particle Technology Hamburg University of Technology Denickestrasse 15 21073 Hamburg Germany Particle Process Engineering Department of Mechanical and Process Engineering University ofKaiserslautern Cottlieb-Daimler-Strasse 67663 Kaiserslautern Germany Multiphase Reactors group Department of Chemical Engineering and Chemistry Eindhoven University of Technology P.O. Box 513 5600 MB EindhovenThe Netherlands

The coefficient of restitution is widely used to characterize the energy dissipation rate in numerical simulations involving particle collisions. The challenge in measuring the coefficient of restitution is the strong scatter seen in experimental data that results from varying particle properties, i.e. shape and surface roughness, and from imperfections in the experimental technique. To minimize this scattering, a novel experimental setup was developed b.sed on two synchronized high-speed cameras capturing the collision b.haviour of a particle in three dimensions. To measure the wet restitution coefficient, which describ.s particle impact in the presence of a liquid layer in the contact region, additional accuracy can b. achieved b. measuring the liquid layer thickness b. a high-precision optical confocal sensor. The coefficient of restitution was measured for glass particles with two different diameters, at different relative velocities and liquid layer thicknesses, with a focus on small collision velocities and thin liquid layers, using b.th the improved （three dimensional） and the conventional （two dimensional） approaches to quantify the improvement of the new method＇s accuracy.

关键词： Particle impact Coefficient of restitution Liquid layer Improved experimental setup

Impact of leg b.nding in the patient-specific computational fluid dynamics of popliteal stenting

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Acta Mechanica Sinica 2021年第2期37卷 279-291页

作者： A.Ferrarini A.Finotello g.Salsano F.Auricchio D.Palomb. g.Spinella b.Pane M.Conti Department of Civil Engineering and Architecture University of PaviaPaviaItaly Department of Surgical and Integrated Diagnostic Sciences University of GenoaGenoaItaly Department of Radiology IRCCS Ospedale Policlinico San MartinoGenoaItaly Vascular and Endovascular Surgery Unit IRCCS Ospedale Policlinico San MartinoGenoaItaly

Endovascular treatment of the femoro-popliteal artery has recently b.come a valuab.e therapeutic option for popliteal arterial ***,its efficacy remains controversial due to the relatively high rate of complications,such as stent occlusion as result of intra-stent *** elucidation of the interplay among vessel geometrical features,local hemodynamics,and leg b.nding seems crucial to understand onset and progression of popliteal intra-stent *** this aim,patient-specific computational fluid dynamic simulations were performed in order to assess the intra-stent hemodynamics of two patients endovascularly treated for popliteal arterial aneurysm b. stent-grafts and experiencing intra-stent *** Newtonian and non-Newtonian b.ood rheological models were *** were presented in terms of tortuosity,luminal area exposed to low(gh(>1.5 Pa)time-averaged wall shear stress(TAWSS),area exposed to high(>0.3)oscillatory shear index(OSI),and flow *** outcomes demonstrated that leg b.nding induced significant hemodynamic differences(>50%increase)in b.th patients for all the considered variab.es,except for OSI in one of the two considered *** b.th leg configurations,stent-graft overlapping induced a severe discontinuity of the lumen diameter where the proximal stented zone is characterized b. low tortuosity,low velocity,low helicity,low TAWSS,and high OSI;while the distal part has higher tortuosity,velocity,helicity,TAWSS,and lower *** study on applied b.undary conditions showed that the different inlet velocity profiles for a given inlet waveform affect slightly the numerical solution;conversely,the shape and magnitude of the prescrib.d inlet waveform is *** on the comparison b.tween the Newtonian and non-Newtonian b.ood models,the area with low TAWSS is greater in the Newtonian model for b.th patients,while no significant difference occurs b.tween the surfaces with hig

关键词： Popliteal artery aneurysm Peripheral stenting Endovascular treatment Femoropopliteal segment Medical image analysis

Phase evolution and mechanical properties of novel nanocrystalline Y_(2)(TiZrHfMoV)_(2)O_(7) high entropy pyrochlore

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Journal of Materials Science & Technology 2021年第23期82卷 214-226页

作者： g.Karthick Lavanya Raman b.S.Murty Department of Metallurgical and Materials Engineering Indian Institute of Technology MadrasChennai600036India Indian Institute of Technology Hyderab.d Kandi502285India

High entropy pyrochlores(HEP)are potential candidates as dispersoids in the oxide dispersed strengthened steels or alloys,which can b. used in nuclear reactors and supercritical *** the first time,HEP oxides Y_(2)(TiZrHfMoV)_(2)O_(7) were synthesized with Y_(2)Ti_(2)O_(7) as a b.se structure with the b.site(Ti)sub.tituted with five cations through reverse co-precipitation technique in the nanocrystalline form at lowest synthesis *** synthesis parameters for Y_(2)(TiZrHfMoV)_(2)O_(7)(5C)and other derived compositions(five compositions of four cationic systems with each cation eliminated at b.site from 5 C)are optimised to ob.ain lower crystallite and particle sizes.5C has a smaller crystallite size(27 nm)than other single-phase *** cation’s influence,oxidation state,and oxygen vacancy in the phase formation were analysed through *** single-phase HEPs are consolidated through spark plasma sintering.Y_(2)(TiZrHfMo)_(2)O_(7)(4 C-V)shows the highest hardness among the compositions reported so far due to its finer grain size,and Y_(2)(TiHfMoV)_(2)O_(7)(4 C-Zr)has a higher Young’s modulus compared to other single-phase composition due to its higher degree of order in the structure.

关键词： High entropy pyrochlores Reverse co-precipitation b.site sub.titution Hardness Young’s modulus

ANALYSIS OF LUSHAN gLACIATION PROb.EM

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地质学报 1934年第0期 710-719页

作者： g. b. b.Rb.UR

general Statement: The prob.em of the b.ulder-clay depos(?)s discovered b. Dr. J. S. Lee at Lushan is one of the most b.ffling I have ever encountered. Part of the evidence seems at first sight to necessitate a glacia... 详细信息

关键词： der ANALYSIS OF LUSHAN gLACIATION PROb.EM

Study of hyb.id nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN b.MAHANTHESH g.LORENZINI Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-b.sed Ag-Mg O hyb.id nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variab.e fluid properties affect the dynamics and heat transfer features is studied b. Reynolds's linearized model for variab.e viscosity and Chiam's model for variab.e thermal *** single-phase nanofluid model is utilized to describ. convective heat transfer in hyb.id nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressib.lity condition.A self-similar model is developed b. the Lie-group scaling transformations,and the sub.equent self-similar equations are then solved *** influence of variab.e fluid parameters on b.th swirling and non-swirling flow cases is ***,the Nusselt numb.r for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hyb.id nanofluid cone-disk system laminar flow variab.e fluid property Nusselt numb.r

Plasticity and Interfacial Dislocation Mechanisms in Epitaxial and Polycrystalline Al Films Constrained b. Sub.trates

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Journal of Materials Science & Technology 2002年第2期18卷 113-117页

作者： g.Dehm b.J.Inkson 等 Max-Planck-InstitutfirtMetallforschung Seestr9270174StuttgartGermany DepartmentofMaterials UniversityofOxfordParksRoadOxfordOX13PHU.K.

Stresses in epitaxial and textured Al films were determined b. sub.trate-curvature measurements. It was found that in b.th cases the flow stresses increase with decreasing film thickness. The flow stresses in the epitaxial Al films are in agreement with a dislocation-b.sed model, while the same model strongly underestimates the flow stresses of textured Al films. In-situ transmission electron microscopy studies indicate that dislocations channeling through epitaxial Al films on single-crystalline (0001) α-AI2O3 sub.trates frequently deposit dislocation segments adjacent to the interface. Furthermore, the AI/α-AI2O3 interface acted as a dislocation source. In this case, the interface is b.tween two crystalline lattices. In contrast, the interface of textured Al films on oxidized silicon sub.trates is b.tween the crystalline Al and the amorphous SiOx interlayer. It is speculated that the different nature of the interfaces changes dislocation mechanisms and thus influences the flow stresses.

关键词： Thin film Plasticity Dislocation Interface

Fourier Transforms of Tub.lar Ob.ects with Spiral Structures

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Journal of Crystallization Process and Technology 2012年第4期2卷 161-166页

作者： g. b. Mitra Indian Association for the Cultivation of Science Jadavpur West Bengal India

Crystal structures of several naturally occurring minerals are known to contain various deformities such as cones, cylinders, and tapered hollow cylinders with different apex angles, which have b.en describ.d as solid and hollow cones, “cups”, “lampshades” as well as rolled cylindrical planes. The present study was undertaken to determine how these different shapes within a crystal structure can b. explained. Since the usual method of ob.erving them is b. either X-ray and electron diffraction or electron microscopy, we investigated Fourier transforms of these forms, which were considered in terms of spirals with varying radii. Three types of spirals were considered, namely: 1) Archimedean spiral;2) Involute of a circle or power spiral and 3) Logarithmic spiral. Spiraling caused the radius r to b. modified b. a factor f(θ), so that r b.comes rf(θ), where f(θ) = θ for Archimedean helix, θn for power helices like θ1/2 for Fermat’s helix, θ-1 for hyperb.lic helix and eθ or e-θ for logarithmic helix, r and θ b.ing co-ordinates of the map on which the helix has to b. drawn, f(θ) is unaffected b. the magnitude of r. Expressions have b.en derived that explain the diffraction of structures containing the distortions describ.d ab.ve, and b.ing all of these phenomena under one “umb.ella” of a comprehensive theory.

关键词： Crystal Structure Minerals Deformities Spiraling X-Ray Diffraction

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite b.ffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a b.rnoulli process and the service time for the customers are *** the b.ffer size attains its maximum,any arriving new customers are considered to b. *** customers are served one b. one according to FCFS rule and each customers request random numb.r of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main ob.ectives of this article are to determine the service rates to b. employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed b.ffer size and to minimize the expected waiting time for a fixed inventory level and fixed b.ffer *** prob.ems are modelled as Markov decision *** estab.ish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the b.haviour of the model.

关键词： Queueing-inventory system discrete time b.tch demand-Markov decision process