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A simple and distinguished nebulizer approach to prepare cdS thin films

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Journal of Energy chemistry 2017年第3期26卷 398-405页

作者： M.Girish r.Sivakumar c.Sanjeeviraja r.Gopalakrishnan Department of Physics Alagappa UniversityKaraikudi 630003India Department of Physics Alagappa Chettiar College of Engineering and TechnologyKaraikudi 630003India Department of Physics Anna UniversityChennai 600025India

In this paper, we report the substrate temperature induced change in structural, optical, morphological,luminescence and photoelectrochemical properties of cdS films deposited by a simple and facile approach called nebulized spray pyrolysis technique. X-ray diffraction study confirmed the deposited cdS films belong to hexagonal wurtzite structure, with preferential orientation along c-axis,(002) direction perpendicular to the substrate plane. The crack free, unifor., and homogeneously distributed spherical particles are witnessed from AFM image. Various optical parameters like energy band gap, optical conductivity,refractive index, extinction coefficient, dielectric constants, and dispersion energy parameters of the films were evaluated. The strong band edge emission observed in the PL study may be attributed to the recombination of excitations and/or shallowly trapped electron-hole pairs. The first and second overtone of LO modes of cdS at 302 and 600 cm-1are observed in the raman study. The photoelectrochemical properties of the films were also tested.

关键词： Semiconductors chemical synthesis Optical properties X-ray diffraction

Simple shear extrusion versus equal channel angular pressing:A comparative study on the microstructure and mechanical properties of an Mg alloy

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Journal of Magnesium and Alloys 2023年第5期11卷 1769-1790页

作者： A.rezaei r.Mahmudi c.cayron r.E.Logé School of Metallurgical and Materials Engineering College of EngineeringUniversity of TehranNorth Kargar StreetTehran 14395-515Iran Laboratory of Thermomechanical Metallurgy-PX Group chair Ecole Polytechnique Fédérale de Lausanne(EPFL)Neuchâtel CH-2002Switzerland

Two severe plastic defor.ation(SPD)techniques of simple shear extrusion(SSE)and equal channel angular pressing(EcAP)were employed to process an extruded Mg-6Gd-3Y-1.5Ag(wt%)alloy at 553 K for.1,2,4 and 6 *** microstructural evolutions were studied by electron back scattered diffraction(EBSD)analysis and transmission electron microscopy(TEM).The initial grain size of 7.5μm in the extruded alloy was reduced to about 1.3μm after 6 SPD *** dynamic recrystallization was suggested to be operative in both SSE and EcAP,with also a potential contribution of continuous dynamic recrystallization at the early stages of *** difference in the shear strain paths of the two SPD techniques caused different progression rate of dynamic recrystallization(DrX),so that the alloys processed by EcAP exhibited higher fractions of recrystallization and high angle grain boundaries(HAGBs).It was revealed that crystallographic texture was also significantly influenced by the difference in the strain paths of the two SPD methods,where dissimilar basal plane texture components were *** compression tests,perfor.ed along extrusion direction(ED),indicated that the compressive yield stress(cYS)and ultimate compressive strength(UcS)of the alloys after both SEE and EcAP augmented continuously by increasing the number of ***-processed alloys had lower values of cYS and UcS compared to their counterparts processed by *** difference in the mechanical responses was attributed to the different configurations of basal planes with respect to the loading direction(ED)of each SPD technique.

关键词： Mg-Gd-Y alloys Severe plastic defor.ation Simple shear extrusion Equal channel angular pressing Dynamic recrystallization Mechanical properties

Growth response of three plantation species of the tropics exposed to elevated cO_2 levels

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Journal of for.stry research 2013年第3期24卷 449-456页

作者： rekha r. Warrier c. Buvaneswaran P. Priyadharshini r.S.c. Jayaraj Institute of for.st Genetics and Tree Breeding Forest CampusR. S. Puram Coimbatore 641002 India

The response of for.st trees, the largest carbon sinks on the earth, to continuing rise in atmospheric carbon levels is unknown. re- ports state that increasing levels of atmospheric cO2 will stimulate pho- tosynthesis and productivity in most ecosystems. However, the duration and magnitude of this stimulation, particularly in the tropics, remains a question. To investigate the effects of cO2 fertilization on plant growth, seedlings of three common plantation species, casuarina equisetifolia, Ailanthus excelsa and Tectona grandis were grown in closed chambers enriched with cO2. After 180 days of treatment, morphological traits of seedling height, biomass of root and shoot and root-shoot allometric co-efficient were measured. The activity of carbonic anhydrase and con- tents of chlorophylls, total carbohydrates and soluble proteins were de- termined. In Tectona grandis, significant effects of cO2 supply were found on chlorophylls, root-shoot allometric ratio and seedling quality index. Ailanthus excelsa showed significant effect on only the shoot characteristics on exposure to elevated cO2 but the root characteristics and concentrations of chlorophylls were not significantly different. ca- suarina equisetifolia also showed significant effects on exposure to ele- vated cO2 in terms of shoot characteristics and concentrations of chlo- rophylls. Total sugars, the major photosynthates, did not show any sig- nificant variation to elevated cO2 in any of the three species. carbonic anhydrase, the key enzyme responsible for.transfer of cO2 into the tis- sues significantly increased in all three species. Overall, all the variables responded to elevated cO2, reflecting the positive effects of one parame- ter of climate change conditions on seedling quality. A positive response of these three plantation species to elevated cO2 content is a good indi- cation for.their future existence in potentially changed climatic eonditions.

关键词： Plantation Elevated cO2 Tropical trees India carbonicanhydrase

OH and O radicals production in atmospheric pressure air/ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： N c rOY M r TALUKDEr A N cHOWDHUrY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial research Laboratory rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for.the characterization of plasmas and for.identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. relative intensities of OH and O radicals indicate that their production rates are increased with increasing ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(rOS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Dynamic response of composite Materials with 2D reduced Micromorphic Model

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Acta Mechanica Solida Sinica 2022年第4期35卷 603-615页

作者： A.r.El Dhaba c.W.Lim Department of Mathematics Faculty of ScienceDamanhour UniversityDamanhourEgypt Department of architecture and civil Engineering City University of Hong KongKowloonHong Kong SARChina

In this article,we introduce a complete set of constitutive relations and field equations for.the linear reduced micromorphic *** further investigate the internal variables and their relationship in the case of two-dimensional(2D)wave *** dynamic response is investigated for.composite materials,which is due to an external wave in two dimensions applied at the boundary of the considered *** solutions for.the model are unavailable at this stage due to dependency of the field equations on spatial and time variables in a complicated manner.A finite element approach is adopted to derive approximate solutions for.the field equations,and numerical finite element solutions for.the internal fields are presented in detail and discussed.

关键词： composite materials Finite element method(FEM) reduced micromorphic model Wave propagation

Impact of the blockage ratio on the transport of sediment in the presence of a hydrokinetic turbine: Numerical modeling of the interaction sediment and turbine

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International Journal of Sediment research 2021年第6期36卷 696-710页

作者： Fatima Khaled Sylvain Guillou Yann Méar Ferhat Hadri University of caen Normandy LISV University of Versailles conservatoire National des arts et Métiers University of Caen Normandy

Interactions between hydrokinetic turbines and near scale and far scale bed sediment particles are considered a critical area of assessment; however, a limited number of research studies have been published to address this issue. The current paper explores the influence of the blockage ratio on the morphology evolution downstream from a hydrokinetic turbine. A modeling framework is derived to predict the significant transport induced by a turbine installed on the erodible fluvial sandy bed surface,such as the Eulerian multi-phase model for.the sediment and the Blade Element Momentum Theory(BEMT) for.the turbine, using the open source platfor. OpenFOAM. Two configurations of different blockage ratios are considered. The configurations show differences in the bed morphology and the sediment transport. It has been shown for.both configurations that the scour capabilities are enhanced below the turbine due to the acceleration of the flow and increasing local shear stress on the sediment.

关键词： Environmental impact Blockage effects Euler-Euler multiphase Hydrokinetic turbine Numerical simulations OpenFOAM

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： r.A.JAFarI-TALOOKOLAEI H.GHANDVar E.JUMAEV S.KHATIr T.cUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science center for.Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external for.e are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the for.e vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and for.e vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy

Fine mapping and identification of candidate genes for.the peach powdery mildew resistance gene Vr3

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Horticulture research 2020年第1期7卷 343-351页

作者： Neus Marimon Jordi Luque Pere arús Iban Eduardo centre for.research in Agricultural Genomics(crAG)cSIc-IrTA-UAB-UB Campus UAB08193 BellaterraBarcelonaSpain IrTA(Institut de recerca i Tecnologia Agroalimentàries) BarcelonaSpain Plant Pathology IRTA CabrilsCarretera de Cabrils km 208348 CabrilsSpain

Powdery mildew is one of the major diseases of peach(Prunus persica),caused by the ascomycete Podosphaera ***,it is controlled through calendar-based fungicide treatments starting at petal fall,but an alternative is to develop resistant peach *** studies mapped a resistance gene(Vr3)in interspecific populations between almond(‘Texas’)and peach(‘Earlygold’).To obtain molecular markers highly linked to Vr3 and to reduce the number of candidate genes,we fine-mapped Vr3 to a genomic region of 270 kb with 27 annotated *** find evidence supporting one of these positional candidate genes as being responsible of Vr3,we analyzed the polymorphisms of the resequences of both parents and used near-isogenic lines(NILs)for.expression analysis of the positional candidate genes in symptomatic or asymptomatic *** differentially expressed between resistant and susceptible individuals were annotated as a Disease resistance Protein rGA2(Prupe2G111700)or an Eceriferum 1 protein involved in epicuticular wax biosynthesis(Prupe2G112800).Only Prupe2G111700 contained a variant predicted to have a disruptive effect on the encoded protein,and was overexpressed in both heterozygous and homozygous individuals containing the Vr3 almond allele,compared with susceptible *** infor.ation was also useful to identify and validate molecular markers tightly linked and flanking *** addition,the NILs used in this work will facilitate the introgression of this gene into peach elite materials,alone or pyramided with other known resistance genes such as peach powdery mildew resistance gene Vr2.

关键词： resistance peach mapping

Optimization of Machining characteristics for.Al/Sicp composites using ANN/GA

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Journal of Materials Science & Technology 2002年第1期18卷 47-50页

作者： r.Karthikeyan B.c.Pai 等 DepartmentofProductionEngineering AnnamalaiUniversityAnnamalainagar-608002India regionalresearchLaboratory ThiruvananthapuramIndia

The present work is focused on optimization of machining characteristics of AI/Sicp composites. The machining characteristics such as specific energy, tool wear and surface roughness were studied. The parameters such as volume fraction of Sic, cutting speed and feed rate were considered. artificial neural networks (ANN) was used to train and simulate the experimental data. Genetic algorithms (GA) was interfaced with ANN to optimize the machining conditions for.the desired machining characteristics. Validation of optimized results was also perfor.ed by confirmation experiments.

关键词： Al/Sicp composites artificial neural networks Genetic algorithms