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microsystems & Nanoengineering 2022年第3期8卷 163-176页

作者： elsbeth g.b.m.bossink Anke R.Vollertsen Joshua T.Loessberg-Zahl Andries D.van der meer Loe l.Segerink mathieu Odijk bIOs Lab on a Chip group MESA+instituteTechnical Medical CenterMax Planck Institute for Complex Fluid DynamicsUniversity of TwenteEnschedeThe Netherlands Applied Stem Cell Technologies group Technical Medical CenterUniversity of TwenteEnschedeThe Netherlands

Integrated valves enable automated control in microfuidic systems,as they can be applied for mixing,pumping and compartmentalization *** automation would be highly valuable for applications in organ-on-chip(OoC)***,OoC systems typically have channel dimensions in the range of hundreds of micrometers,which is an order of magnitude larger than those of typical microfluidic *** most-used fabrication process for integrated,normally open polydimethylsiloxane(PDmS)valves requires a reflow photoresist that limits the achievable channel *** addition,the low stroke volumes of these valves make it challenging to achieve flow rates of microliters per minute,which are typically required in OoC ***,we present a mechanical'macrovalve'fabricated by multilayer soft lithography using micromilled direct *** demonstrate that these valves can close off rounded channels of up to 700μm high and 1000μm ***,we used these macrovalves to create a peristaltic pump with a pumping rate of up to 48μL/min and a mixing and metering device that can achieve the complete mixing of a volume of 6.4μL within only 17 *** initial cell culture experiment demonstrated that a device with integrated macrovalves is biocompatible and allows the cell culture of endothelial cells over multiple days under continuous perfusion and automated medium refreshment.

关键词： pumping mixer pump

Comparisons of electrical and optical properties between graphene and silicene A review

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Chinese Physics b 2018年第2期27卷 299-313页

作者： Wirth-Lima A J Silva m g Sombra A S b Laboratory of Telecommunications and materials Science and Engineering-www.locem.ufc.br-Fortaleza CearaBrazil Department of Physics Science CenterFederal University of Ceara(U.F C.)-FortalezaCear4Brazil State University of Vale do Acarau SobralCeardBrasil

Two-dimensional （2D） metamaterials are considered to be of enormous relevance to the progress of all exact sciences. Since the discovery of graphene, researchers have increasingly investigated in depth the details of electrical/optical proper- ties pertinent to other 2D metamaterials, including those relating to the silicene. In this review are included the details and comparisons of the atomic structures, energy diagram bands, substrates, charge densities, charge mobilities, conductivities, absorptions, electrical permittivities, dispersion relations of the wave vectors, and supported electromagnetic modes related to graphene and silicene. Hence, this review can help readers to acquire, recover or increase the necessary technological basis for the development of more specific studies on graphene and silicene.

关键词： graphene silicene electrical/optical properties

Electro-magneto-hydrodynamic flow of couple stress nanofluids in micro-peristaltic channel with slip and convective conditions

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Applied mathematics and mechanics(English Edition) 2021年第4期42卷 593-606页

作者： K.RAmESH m.g.REDDY b.SOUAYEH Department of mathematics Symbiosis Institute of TechnologySymbiosis International(Deemed University)Pune 412115India Department of mathematics Acharya Nagarjuna UniversityOngole CampusOngole 523001India Department of Physics College of ScienceKing Faisal UniversityAl-Ahsa 31982Saudi Arabia Laboratory of Fluid mechanics Physics DepartmentFaculty of Sciences of TunisUniversity of Tunis El ManarTunis 2092Tunisia

This study explores the effects of electro-magneto-hydrodynamics,Hall currents,and convective and slip boundary conditions on the peristaltic propulsion of nanofluids(considered as couple stress nanofluids)through porous symmetric *** phenomena of energy and mass transfer are considered under thermal radiation and heat source/*** governing equations are modeled and non-dimensionalized under appropriate dimensionless *** resulting system is solved numerically with mATHEmATICA(with an in-built function,namely the Runge-Kutta scheme).graphical results are presented for various fluid flow quantities,such as the velocity,the nanoparticle temperature,the nanoparticle concentration,the skin friction,the nanoparticle heat transfer coefficient,the nanoparticle concentration coefficient,and the trapping *** results indicate that the nanoparticle heat transfer coefficient is enhanced for the larger values of thermophoresis ***,an intriguing phenomenon is observed in trapping:the trapped bolus is expanded with an increase in the Hartmann ***,the bolus size decreases with the increasing values of both the Darcy number and the electroosmotic parameter.

关键词： peristalsis magnetohydrodynamics(mHD) nanofluid Hall current porous medium thermal radiation

High Temperature Deformation behavior of 4340 Steel: Activation Energy Calculation and modeling of Flow Response

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Journal of Iron and Steel Research International 2013年第12期20卷 133-139页

作者： S V Sajadifar g g Yapici m Ketabchi b bemanizadeh mechanical Engineering Department Ozyegin University mining and metallurgical Engineering Department Amirkabir University of Technology Islamic Azad University Karaj Branch

The 4340 steel is extensively utilized in several industries including automotive and aerospace for manufac- turing a large number of structural components. Due to the importance of thermo-mechanical processing in the pro- duction of steels, the dynamic recrystallization （DRX） characteristics of 4340 steel were investigated. Namely, hot compression tests on 4340 steel have been performed in a temperature range of 900-- 1200 ℃ and a strain rate range of 0.01--1 s-1 and the strain of up to 0.9. The resulting flow stress curves show the occurrence of dynamic recrys- tallization. The flow stress values decrease with the increase of deformation temperature and the decrease of strain rate. The microstrueture of 4340 steel after deformation has been studied and it is suggested that the evolution of DRX grain structures can be accompanied by considerable migration of grain boundaries. The constitutive equations were developed to model the hot deformation behavior. Finally based on the classical stress-dislocation relations and the kinematics of the dynamic recrystallization; the flow stress constitutive equations for the dynamic recovery period and dynamic reerystallization period were derived for 4340 steel, respectively. The validity of the model was demon- strated by demonstrating the experimental data with the numerical results with reasonable agreement.

关键词： 4340 steel hot deformation activation energy dynamic recrystallization, modeling strain rate sen- sitivity

Effects of of Habitats and Pesticides on Aerobic Capacity and Survival of Soil Fauna

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biomedical and Environmental Sciences 2005年第3期18卷 169-175页

作者： g. TRIPATHI b. m. SHARmA Department of Zoology J. N. Vyas University Jodhpur-342 001 IndiaDepartment of Zoology J. N. Vyas University Jodhpur-342 001 India

Objective Faunal health is largely dependent on their soil environment and available litter quality. So the effects of different soil habitats and pesticides on citrate synthase (CS) activity of soil fauna and its population were studied. methods The soil animals were collected from different pedoecosystems for habitat study. Whereas Vigna radiata based system was selected for pesticidal observations. The field was divided into five equal plots for control and treatment of γ-bHC, quinalphos, carbaryl and cypermethrin. Soil fauna was collected by quadrat method and extracted by Tullgren funnel. Individuals of a species having similar sizes were collected for the estimation of CS activity. They were homogenized and fractions were obtained by differential centrifugation. The activity of CS was assayed spectrophotometrically. Results Citrate synthase (CS) activity of beetle (Rasphytus fregi), woodlouse (Porcellio laevis) and centipede (Scolopendra morsitans) varied significantly with respect to changes in different soil habitats. Though the CS activity of R. fregi, P. laevis, and S. morsitans differed among themselves but the highest activity of CS in these animals was in V. radiata and lowest in A. nilotica based pedoecosystem. The aerobic capacity of centipede was maximum followed by woodlouse and beetle. The treatment of γ-bHC, quinalphos, carbaryl and cypermethrin significantly reduced the CS activity of these animals. γ-bHC showed maximum reduction in CS activity indicating highly toxic effect of organochlorine on aerobic metabolism of soil fauna. However, minimum reduction was observed in response to carbaryl (in beetle) or cypermethrin (in woodlouse/centipede) leading to impairment of aerobic capacity. The differences in pesticide effects might be assigned to the differences in chemical nature of pesticides and their interactions with below-ground fauna. Treatment of γ-bHC and quinalphos reduced the population of Acari, Coleoptera, Collembola, other arthropods as

关键词： Citrate synthase Habitat Pesticide Soil fauna and desert

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

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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

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

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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

mitochondria–cgAS–STINg axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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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

Fauna-associated Changes in Chemical and biochemical Properties of Soil

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biomedical and Environmental Sciences 2006年第6期19卷 422-426页

作者： g. TRIPATHI b. m. SHARmA Department of Zoology J. N. V. UniversityJodhpur-342 001India

Objective To study the impacts of abundance of woodlice, termites, and mites on some functional aspects of soil in order to elucidate the specific role of soil fauna in improving soil fertility in desert. methods Fauna-rich sites were selected as experimental sites and adjacent areas were taken as control, Soil samples were collected from both sites. Soil respiration was measured at both sites. The soil samples were sent to laboratory, their chemical and biochemical properties were analyzed. Results Woodlice showed 25% decrease in organic carbon and organic matter as compared to control site. Whereas termites and mites showed 58% and 16% decrease in organic carbon and organic matter. In contrast, available nitrogen （nitrate and ammonical both） and phosphorus exhibited 2-fold and 1.2-fold increase, respectively. Soil respiration and dehydrogenase activity at the sites rich in woodlice, termites and mites produced 2.5-, 3.5- and 2-fold increases, respectively as compared to their control values. Fauna-associated increase in these biological parameters clearly reflected fauna-induced microbial activity in soil. maximum decrease in organic carbon and increase in nitrate-nitrogen and ammonical-nitrogen, available phosphorus, soil respiration and dehydrogenase activity were produced by termites and minimum by mites reflecting termite as an efficient soil improver in desert environment. Conclusion The soil fauna-associated changes in chemical （organic carbon, nitrate-nitrogen, ammonical-nitrogen, phosphorus） and biochemical （soil respiration, dehydrogenase activity） properties of soil improve soil health and help in conservation of desert pedoecosystem.

关键词： Soil fauna Organic carbon Nitrogen Phosphorus Soil respiration Dehydrogenase activity

ON PERTURbED AbSTRACT FUNCTIONAL INTEgRODIFFERENTIAL EQUATION

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Acta mathematica Scientia 1988年第3期8卷 263-282页

作者： m.b.Dhakne,b.g.Pachpatte Dept.of math.& Stat. marathwada Univ. Aurangabad India Dept.of math.& Stat. marathwada Univ. Aurangabad India

In the present paper the existence of a unique strong solution of a general nonlinear perturbed abstract functional integ odifferential equation is investigated. The technique used in the proof of our main r esult is based on Kato's approach recently extended by Kartsatos and Parrott to evolution equations involving functional perturbations.

关键词： lim Holder 一夕