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Nonlocal buckling of embedded magnetoelectroelastic sandwich nanoplate using refined zigzag theory

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Applied mathematics and mechanics(English Edition) 2018年第4期39卷 529-546页

作者： A.GHORBANPOUR-ARANI F.KOLAHDOUZAN m.ABDOLLAHIAN Faculty of mechanical Engineering University of Kashan Institute of Nanoscience & Nanotechnology University of Kashan

This paper is concerned with a buckling analysis of an embedded nanoplate integrated with magnetoelectroelastic(mEE) layers based on a nonlocal magnetoelectroelasticity theory. A surrounding elastic medium is simulated by the Pasternak foundation that considers both shear and normal loads. The sandwich nanoplate(SNP) consists of a core that is made of metal and two mEE layers on the upper and lower surfaces of the core made of Ba Ti O3/Co Fe2 O4. The refined zigzag theory(RZT) is used to model the SNP subject to both external electric and magnetic potentials. Using an energy method and Hamilton’s principle, the governing motion equations are obtained, and then solved analytically. A detailed parametric study is conducted, concentrating on the combined effects of the small scale parameter, external electric and magnetic loads, thicknesses of mEE layers, mode numbers, and surrounding elastic medium. It is concluded that increasing the small scale parameter decreases the critical buckling loads.

关键词： sandwich nanoplate(SNP) refined zigzag theory(RZT) nonlocal magnetoelectroelasticity theory buckling magnetostrictive layer

An investigation of reaction furnace temperatures and sulfur recovery

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Frontiers of Chemical Science and Engineering 2011年第3期5卷 362-371页

作者： S.ASADI m.PAKIZEH m.POURAFSHARI CHENAR Chemical Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhad P.O.Box 91775-1111Iran

In a modern day sulfur recovery unit(SRU),hydrogen sulfide(H_(2)S)is converted to elemental sulfur using a modified Claus unit.A process simulator called TSWEET has been used to consider the Claus *** effect of the H_(2)S concentration,the H_(2)S/CO_(2) ratio,the input airﬂow rate,the acid gasﬂow of the acid gas(AG)splitter and the temperature of the acid gas feed at three different oxygen concentrations(in the air input)on the main burner temperature have been *** the effects of the tail gas ratio and the catalytic bed type on the sulfur recovery were *** bed temperatures were optimized in order to enhance the sulfur recovery for a given acid gas feed and air *** when the fraction of AG splitterﬂow to the main burner was increased,the temperature of the main burner increased to a maximum but then decreased sharply when theﬂow fraction was further increased;this was true for all three concentrations of ***,if three other parameters(the concentration of H_(2)S,the ratio H_(2)S/CO_(2) and theﬂow rate of air)were increased,the temperature of the main burner increased *** increase had differ-ent slopes depending on the oxygen concentration in the input ***,by increasing the temperature of the acid gas feed,the temperature of the main burner *** general,the concentration of oxygen in the input air into the Claus unit had little effect on the temperature of the main burner(This is true for all parameters).The optimal catalytic bed temperature,tail gas ratio and type of catalytic bed were also determined and these conditions are a minimum temperature of 300°C,a ratio of 2.0 and a hydrolysing Claus bed.

关键词： Claus unit concentration of H_(2)S tail gas ratio sulfur recovery catalytic bed

The Response of the Earth's Lower Ionosphere to Gamma-Ray Solar Flares and their Associated X-ray

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Research in Astronomy and Astrophysics 2022年第4期22卷 137-152页

作者： mahmoud mohery Hussein m.Farid Alaa Ali Dept.of Phys College of ScienceUniversity of JeddahJeddahSaudi Arabia Astronomy Space Science&Meteorology DepartmentFaculty of ScienceCairo UniversityGiza 12613Egypt Astronomy Dept. Faculty of ScienceKing Abdulaziz University21589 JeddahSaudi Arabia

The present work aims to explore the impact of solar gamma-ray fiares(GRFs),detected by the Fermi-Large Area Telescope(LAT),and their associated X-ray fiares(XRFs)on the Earth’s lower *** data of ionospheric parameter fmin were collected from the Yamagawa mid-latitude ionosonde station in *** most of the GRFs used in this study are associated with soft X-ray(SXR)emissions,detected by the Geostationary Operational Environmental Satellite(GOES),we classified them into three types:simultaneous(S),delayed(D)and not associated(N),refiecting the phase occurrence of the solar ***,the ionospheric D layer responds strongly to XRFs more than *** temporal profiles of the ionospheric parameter fmin show distinct behaviors as a response to the various GRF *** the case of the S-type,a single strong peak,with an average value of 5.2 mHz,emanates in the fmin profile within an average interval of time of less than half an *** the case of the D-type,two successive peaks appear in the fmin profile,with an average value of 6.0 mHz for the second peak through a time interval of one hour after the onset of gamma-ray(GR)*** response of the fmin parameter to the N-type fiares appears as a single peak with an average value of 4.8 mHz within about an *** notice that the difference between the fmin peak values and the corresponding reference ones(dfmin)is more convenient and representative than the fmin values,where the median GR fiux of the S-,D-and N-types tends to increase as the average dfmin increases.

关键词： Sun:X-rays gamma-rays Earth:ionosphere satellites

Proposed models for Subcritical Water Extraction of Essential Oils

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Chinese Journal of Chemical Engineering 2009年第3期17卷 359-365页

作者： m.Khajenoori A.Haghighi Asl F.Hormozi Chemical Engineering Department Faculty of EngineeringSemnan University

mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to deter-mine whether the extractions were limited primarily by the near equilibrium partitioning of the analyte between the matrix and solvent (i.e. partitioning thermodynamics) or by the rates of analyte desorption from the matrix (i.e. ki-netics). Four simple models have been applied to describe the extraction profiles obtained with SW: (1) a model based solely on the thermodynamic distribution coefficient KD, which assumes that analyte desorption from the ma-trix is rapid compared to elution; (2) one-site kinetic model, which assumes that the extraction rate is limited by the analyte desorption rate from the matrix, and is not limited by the thermodynamic (KD) partitioning that occurs dur-ing elution; (3) two-site kinetic model and (4) external mass transfer resistance model. For SW extraction, the thermodynamic elution of analytes from the matrix was the prevailing mechanism as evidenced by the fact that ex-traction rates increased proportionally with the SW flow rate. This was also confirmed by the fact that simple re-moval calculations based on determined KD (for major essential oil compounds) gave good fits to experimental data for flow rates from 1 to 4 ml·min-1. The results suggested that the overall extraction mechanism was influenced by solute partitioning equilibrium with external mass transfer through liquid film.

关键词： essential oils Zataria multiflora Boiss. subcrltlcal water extraction mechanisn

Al–TiO_2–Gr powder metallurgy hybrid composites with cold upset forging

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Rare metals 2014年第6期33卷 686-696页

作者： m.Ravichandran A.Naveen Sait V.Anandakrishnan Department of mechanical Engineering Chendhuran College of Engineering and Technology Department of Production Engineering National Institute of Technology

The cold upsetting studies were carried out for the aluminium metal matrix hybrid composites in the present study. Aluminium metal matrix hybrid composites were synthesised through powder metallurgy route from ball-milled powders to yield the following compositions：Al ＋ 2.5 wt% TiO2＋ 2 wt% Gr, Al ＋ 2.5 wt% TiO2＋ 4 wt% Gr, Al ＋ 5.0 wt% TiO2＋ 2 wt% Gr and Al ＋ 5.0 wt% TiO2＋ 4 wt% Gr. The compaction process was carried out using suitable punch and die in 40 k N hydraulic press, and sintering was done in an electric muffle furnace at the temperature of 590 °C for 3 h. The sintered preforms were subjected to incremental compressive loading of 10 k N until the cracks were found at the free surface. The true axial stress, true hoop stress, true hydrostatic stress and true effective stress were calculated for all the preforms, and all these stresses are correlated with the true axial strain. The stress ratio parameters（rz/reff, rh/reff, rz/rmand rh/rm） of the all preforms were correlated with true axial strain. The maximum true axial stress, true hoop stress, true effective stress and hydrostatic static stress are obtained for the composite containing5 wt% of TiO2 and 4 wt% of graphite and the minimum ones are obtained for composite containing 2.5 wt% of TiO2 and 2 wt% of graphite.

关键词： metal matrix composites Cold upsetting Powder metallurgy

Surface plasmon polariton at the interface of dielectric and graphene medium using Kerr effect

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Chinese Physics B 2018年第11期27卷 522-527页

作者： Bakhtawar muhammad Haneef B A Bacha H Khan m Atif Lab of Theoretical Physics Department of Physics Hazara University Department of Physics University of Malakand

We theoretically investigate the control of surface plasmon polariton（SPP） generated at the interface of dielectric and graphene medium under Kerr nonlinearity. The controlled Kerr nonlinear signal of probe light beam in a dielectric medium is used to generate SPPs at the interface of dielectric and graphene medium. The positive, negative absorption, and dispersion properties of SPPs are modified and controlled by the control and Kerr fields. A large amplification（negative absorption） is noted for SPPs under the Kerr nonlinearity. The normal/anomalous slope of dispersion and propagation length of SPPs is modified and controlled with Kerr nonlinearity. This leads to significant variation in slow and fast SPP propagation. The controlled slow and fast SPP propagation may predict significant applications in nano-photonics, optical tweezers, photovoltaic devices, plasmonster, and sensing technology.

关键词： surface plasmon polariton Kerr nonlinearity graphene

Geochemistry of metasedimentary rocks of the Sonakhan and mahakoshal greenstone belts,Central India:Implications for paleoweathering,paleogeography and mechanisms of greenstone belt development

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Acta Geochimica 2022年第1期41卷 64-83页

作者： Hamidullah Wani m.E.A.mondal Iftikhar Ahmad Department of Geology Government Degree College for Women PulwamaJammu and Kashmir 192301India Department of Geology Aligarh Muslim UniversityAligarhUttar Pradesh 202002India

A comparative study of the Precambrian Sonakhan(SGB)and mahakoshal(mGB)greenstones belts of Central India has been undertaken to decipher their provenance,paleoweathering,paleogeography,and *** compared to the Upper Continental Crust(UCC),the mGB samples are enriched while the SGB samples are depleted in mafic elements indicating the presence of mafic rocks in the source of the *** is complemented by the Ni–Cr *** REE concentrations,LREE fractionated patterns and negative Eu anomalies of the mGB and SGB samples indicate derivation of sediments from a highly fractionated granitic *** mGB samples also contain the geochemical signature of mafic rocks,it is,therefore proposed that the mGB clastic load were derived from two sources(mafic+felsic)with arc *** is attested by Cr and Zr relationships,and LILE enrichment,and HFSE *** features suggest that the SGB developed as autochthonous while the mGB developed as an allochthonous *** chemical alteration indices such as chemical index of alteration(CIA),plagioclase index of alteration(PIA),and index of compositional variability for mGB samples indicate that they were dominantly derived as the first cycle(with minor recycled)sediments from bimodal sources(dominantly continental arcs)by intense chemical weathering as compared to the SGB samples,which were derived from felsic sources(dominantly cratonic rocks),and partly by recycling through a low chemical *** CIA and PIA values of the samples reveal a change in the climatic conditions from Late Archean to Late *** change is interpreted in terms of migration of the Indian plate from high latitudes in the Late Archean to lower latitudes during the Late *** is consistent with the paleomagnetic data that placed India in the configuration of 2.45 Ga Ur and 1.78 Ga Columbia supercontinents.

关键词： Central Indian Shield Sonakhan and mahakoshal greenstone belts Paleoweathering and paleogeography Greenstone belt development

Fluorescence-guided hepatobiliary surgery with long and short wavelength fluorophores

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Hepatobiliary Surgery and Nutrition 2020年第5期9卷 615-639页

作者： Thinzar m.Lwin Robert m.Hoffman michael Bouvet Department of Surgery University of California San DiegoSan DiegoCAUSA AntiCancer Inc.San DiegoCAUSA VA San Diego Healthcare System San DiegoCAUSA

Importance:Fluorescence-guided surgery(FGS)is a potentially powerful tool for hepatobiliary(HPB)*** high sensitivity of fluorescence navigation is especially useful in settings where tactile feedback is ***:The present narrative review evaluates literature on the use of FDA-approved fluorophores such as methylene blue(mB),5-aminolevulinic acid(5-ALA),and indocyanine green(ICG)for clinical intra-operative image-guidance during HPB *** Review:Approaches such as dosing,timing,imaging devices and comparative endpoints are *** feasibility and safety of fluorophores in visualizing the biliary tree,identify biliary leaks,outline anatomic hepatic segments,identify tumors,and evaluate perfusion and graft function in liver transplants are ***:Tumor-specific probes are a promising advancement in FGS with a greater degree of *** current status of tumor-specific probes being evaluated in clinical trials are *** and Relevance for Reviews:Relevant discussion of promising tumor-specific probes in pre-clinical development are ***-guidance in HPB surgery is relatively new,but current literature shows that the dyes are reliably able to outline desired structures with a variety of dosing,timing,and imaging devices to provide real-time intra-operative anatomic information to *** of tumor-specific probes will further advance the field of HPB surgery especially during oncologic resections.

关键词： Fluorescence-guided surgery(FGS) methylene blue(mB) 5-aminolevulinic acid(5-ALA) indocyanine green(ICG) hepatobiliary surgery(HPB surgery) tumor-specific probes near-infrared fluorescence(NIR fluorescence)

Linear matrix inequality approach for synchronization control of fuzzy cellular neural networks with mixed time delays

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Chinese Physics B 2012年第4期21卷 586-596页

作者： P.Balasubramaniam m.Kalpana R.Rakkiyappan Department of mathematics Gandhigram Rural Institute-Deemed UniversityGandhigram-624302TamilnaduIndia Department of mathematics Bharathiar UniversityCoimbatore-641046TamilnaduIndia

Fuzzy cellular neural networks （FCNNs） are special kinds of cellular neural networks （CNNs）. Each cell in an FCNN contains fuzzy operating abilities. The entire network is governed by cellular computing laws. The design of FCNNs is based on fuzzy local rules. In this paper, a linear matrix inequality （LmI） approach for synchronization control of FCNNs with mixed delays is investigated. mixed delays include discrete time-varying delays and unbounded distributed delays. A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network. By constructing the Lyapunov-Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LmIs. The controller can be easily obtained by solving the derived LmIs. A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method.

关键词： asymptotic stability chaos fuzzy cellular neural networks linear matrix inequalities synchronization