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3-d Temperature Fields in Laminated Shells Subjected to Thermo-Loads

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Structural durability & Health Monitoring 2018年第4期12卷 281-298页

作者： Hai Qian ding Zhou Bin Gu Rathnayaka Mudiyanselage d.M.S. Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang212013PR.China College of Civil Engineering Nanjing Tech UniversityNanjing211816PR.China University of Queensland QueenslandAustralia

The temperature fields in the laminated shells were studied, including opencylindrical shells and cylindrical shells, according to the thermal theory. Analyticalsolution of the temperature in the shells with the known temperature on the surfaces waspresent. The thinning layer approach was introduced to simplify the three-dimensionalheat conduction equation. Firstly, the layered shell was divided into N thinner layers. Thegoverning equation was simplified by replacing the variable r by r0 in the center line ofevery thin layer. The general solutions of temperature satisfying the simplified threedimensionalgoverning equation in single-layered shell were deduced in the cylindricalcoordinate system. Then, the temperature and heat flux relationships between the surfacescould be found by transferring matrixes. According to the continuities of temperature andheat flux in the interface of the laminates, the temperature and heat flux relationships ofthe surfaces were derived. With the temperature condition on the surfaces, the unknowncoefficients in the general solution of temperature were obtained. Finally, the effects fromthe thinning layer approach were eliminated by analyzing different numbers of thin *** validity and accuracy of the proposal method were proved from the convergence andcomparison studies. And several numerical examples were studied to investigated thetemperature effects from surface temperatures, geometric size of the shells andcomposition of layers.

关键词： Analytical solution temperature laminated Shells the analytical method thetransfer matrix method

Air Pollution, Government Pollution Regulation, and Industrial Production in China

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Journal of Systems Science & Complexity 2020年第4期33卷 1064-1079页

作者： CAO dong RAMIREZ Carlos d. School of Economics and Management Xidian UniversityXi’an 710071China department of Economics George Mason UniversityFairfaxVAUnited States

Over the last four decades,a severe deterioration in air quality has accompanied China’s rapid *** a result,the Chinese government has implemented stricter policies and regulation to control air *** this paper,the authors create a measure of government policies on air pollution by tracking all pollution-related government announcements in Chinese *** authors then use this variable,along with measures of actual pollution,to investigate how air pollution,industrial production,and government policies on air pollution are *** authors conduct this investigation nationwide,as well as in five large cities in China.A vector autoregression model suggests that,nationwide,government policies seem to decrease air pollution without significantly affecting industrial ***,the effect appears to be short-lived,dissipating after a few *** addition,the authors find that the dynamic relationship among these variables differs by *** instance,following an adverse air quality shock in Beijing,government efforts to control pollution seem to have an ameliorating city-wide effect,decreasing local air pollution in subsequent *** Shanghai and Guangzhou,while the local government reacts to adverse air pollution shocks,the ameliorating effects are not statistically *** Chengdu and Shenyang,the authors detect no significant local government reaction to adverse air pollution ***,in these cities,local government policies do not impart a statistically measurable effect on air pollution.

关键词： pollution. pollution nationwide

Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.SRINIVASACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

(Super)paramagnetic nanoparticles as platform materials for environmental applications: From synthesis to demonstration

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 15-23页

作者： Wenlu Li John d.Fortner department of Chemical and Environmental Engineering Yale UniversityNew HavenCT 06520USA

Over the past few decades,engineered,(super)paramagnetic nanoparticles have drawn extensive research attention for a broad range of applications based on their tunable size and shape,surface chemistries,and magnetic *** review summaries our recent work on the synthesis,surface modification,and environmental application of(super)paramagnetic *** utilizing high-temperature thermo-decomposition methods,first,we have broadly demonstrated the synthesis of highly monodispersed,(super)paramagnetic nanoparticles,via the pyrolysis of metal carboxylate salts in an organic *** uniform magnetic nanoparticles with various size,composition,and shape can be precisely tuned by controlled reaction parameters,such as the initial precursors,heating rate,final reaction temperature,reaction time,and the *** materials can be further rendered water stable via functionalization with surface mono/bi-layer coating structure using a series of tunable ionic/non-ionic ***,we have demonstrated platform potential of these materials for heavy metal ions sensing,sorption,and separation from the aqueous phase.

关键词： Superparamagnetic nanoparticles Surface functionalization Environmental sensing Heavy metal ion sorption

Further Observation on Tin Whisker from Electroplated Sn-Mn Alloy

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稀有金属材料与工程 2012年第S1期41卷 280-282页

作者： Wilcox G d department of Materials Loughborough UniversityLE11 4EQUK

Tin whiskers from Sn-(0-49 wt%)Mn alloy electroplating on polished mild steel were examined with FEG-SEM with *** raw materials were Hull Cell samples kept in an office ambient with different storage time,up to 240 *** is found that,depending on Mn content and plating microstructure,Sn-Mn alloy shows various types of *** for the whisker forest found previously in Sn-20Mn,there exists another in Sn-(1%-5%)*** latter also has a very short incubation time,less than 4 *** interesting finding is that one type of whiskering with surface cap supports an established model.

关键词： Tin whisker microstructure electroplating

Messages from Powdery Mildew dNA:How the Interplay with a Host Moulds Pathogen Genomes

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Journal of Integrative Agriculture 2014年第2期13卷 233-236页

作者： Pietro d Spanu department of Life Sciences Imperial College LondonLondon SW7 2AZUnited Kingdom

The genomes of the barley, Arabidopsis and pea powdery mildew are significantly larger than those of related fungi. This is due to an extraordinary expansion of retro-trasposons that are evident as repetitive elements in the sequence. The protein coding genes are fewer than expected due to an overall reduction in the size of gene families, a reduction in the number of paralogs and because of the loss of certain metabolic pathways. Many of these changes have also been observed in the genomes of other taxonomically unrelated obligate biotrophic pathogens. The only group of genes that bucks the trend of gene loss, are those encoding small secreted proteins that bear the hall marks of effectors.

关键词： barley powdery mildew genome effectors

On some aspects of compressive properties and serrated flow in Mg-Y-Nd-Zr alloy

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Journal of Rare Earths 2013年第8期31卷 804-810页

作者： H.Azzeddine d.Bradai Faculty of Physics University of Sciences and Technology Houari BoumedieneBP32 El-Alia Bab Ezzouar 16111 Algiers Algeria

The deformation behavior of the Mg-Y-Nd-Zr （WE54） alloy at temperatures between 25 and 400 ℃ was investigated by uniaxial and plans strain compression tests at strain rate values of 10-2 and 10^-4 s^-1. The results showed that the flow stress had a strong dependency on the loading condition. Yield stress and peak stress decreased with increasing deformation temperature and with decrease in the strain rate for both deformation types. The serration flow behavior was observed markedly at high temperatures and under a strain rate of 10^-4S^-1. The serration amplitude for samples deformed by plans strain compression was larger than that by uni- axial compression. Serrated flow was attributed to the interaction of dislocations with precipitates at 300 ℃ and to dynamic discon- tinuous recrystallization effects at 400 ℃.

关键词： Mg-Y-Nd-Zr (WE54) alloy serrated flow dynamic precipitation hot deformation rare earths

Lag times in toe-to-heel air injection(THAI)operations explain underlying heavy oil production mechanisms

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Petroleum Science 2022年第3期19卷 1165-1173页

作者： Wei Wei Ian d.Gates department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaCanada

From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is *** oil combustion processes have a lag time between air injection and liquid production,but the common practice in production data analysis uses simultaneous injection and production data when seeking a relationship between *** this research,the time scales of production for the Kerrobert toe-to-heel air injection(THAI)heavy oil project in Saskatchewan,Canada,is analyzed by using cross correlation analysis,*** delay analysis between air injection and oil *** results reveal two time scales with respect to production response with two distinctive recovery mechanisms:(1)a short time scale response(nearly instantaneous)where oil production peaks right after air injection(directly after opening production well)reflecting cold heavy oil production mechanisms,and(2)a longer time scale(of order of 100-300 days)response where peak production occurs associated with the collective phenomena of air injection,heat generating reactions,heat transfer,and finally,heated mobilized heavy oil drainage to the production *** understanding of the two time scales and associated production mechanisms provides a basis for improving the performance of THAI.

关键词： Heavy oil In situ combustion Toe-to-heel air injection(THAI) Production analysis Lag time

Performance assessment of Alccofine with silica fume,fly ash and slag for development of high strength mortar

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Frontiers of Structural and Civil Engineering 2022年第5期16卷 576-588页

作者： Shivang d.JAYSWAL Mahesh MUNGULE Civil Engineering department Institute of InfrastructureTechnologyResearch and Management(IITRAM)Ahmedabad 380026India

Previous studies on concrete have identified silica fume(SF)as the most effective supplementary material,whereas fly ash(FA)and slag have been identified as economical materials with long term strength *** of blended cement mortar referred to as blended mortar(BM)requires similar *** present study explores the application of Alccofine(AL)as supplementary material and compares its performance with conventional materials namely SF,FA and ground granulated blast furnace slag(GGBS).The mortar specimens with binder to fine-aggregates(b/f)ratio of 1:2 are prepared at water to binder(w/b)ratios of 0.4 and *** strength values and stress-strain curve for control and BM specimens are obtained at 7,28,56,and 90 d curing *** assessment based on strength activity index,k-value method and strength estimation model confirms that AL,despite lower pozzolanic activity,contributes to strength gain,due to reduced dilution *** of stress-strain curves suggests that the effect of w/b ratio is more dominant on the elastic modulus of BM specimens than on control *** observations from the study identify enhanced strength gain,improved elastic modulus and higher energy absorption as key contributions of AL making it a potential supplementary material.

关键词： Alccofine high strength mortar efficiency factor dilution effect