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Spark plasma sintering of a high-energy ball milled mg-10 wt% Al alloy

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Journal of magnesium and Alloys 2020年第2期8卷 319-328页

作者： m.U.f.khan A.Patil J.Christudasjustus T.Borkar R.k.Gupta Department of Chemical Biomolecularand Corrosion EngineeringThe University of AkronAkronOH 44325United States Department of mechanical Engineering Washkevicz College of EngineeringCleveland State UniversityClevelandOH 44115United States

The influence of spark plasma sintering(SPS)temperature on microstructure,hardness and corrosion behavior of a high-energy ball milled mg-10wt%Al alloy was investigated in this *** holding time and sintering pressure for SPS were kept constant while varying the sintering temperature from 200 to 350℃.The grain size and microstructure were studied using X-ray diffraction analysis,scanning electron microscopy,energy dispersive X-ray spectroscopy,and Archimedes'based density *** behavior was investigated using potentiodynamic polarization *** nanocrystalline regime(grain sizem)was maintained even after SPS up to 350℃.The density of the alloy increased with increasing the SPS ***'hardness and corrosion performance improved up to 300℃ followed by a decrease after SPS at 350℃.Possible reasons for densification,strengthening,and corrosion behavior have been discussed in the light of reduced porosity and microstructural changes.

关键词： Nanocrystalline alloy magnesium High energy ball milling Spark plasma sintering Corrosion

HREm STUDY Of THE AUSTENITE/mARTENSITE INTERfACES IN AN fe-9Ni ALLOY

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Acta metallurgica Sinica(English Letters) 1997年第5期10卷 386-391页

作者： Li, G.L. meng, X.m. Zhang, f.T. Wu, Y.k. Inst of metal Research Chinese Acad of Sciences Shenyang China

The atomic level structures of fcc/bcc interfaces in an fe-9Ni alloy have been examined by means of HREm. It has been found that the orientation of γ prime /α interface had great effects on its atomic structure. These interfaces with different orientations may be composed of only structural ledges, structural ledges with misfit dislocations, superledges with misfit dislocations or only misfit dislocations. A structural model of growth ledge was suggested. The terrace of growth ledge was composed of structural ledges or misfit dislocations. The atomic structure of the riser of growth ledge was the same as that of the side facet of γ prime lath, which is composed of superledges with misfit dislocations.

关键词： Austenite Electron microscopy Interfaces (materials) martensite Nickel alloys

Remodeling of the plasma for sperm-egg recognition： proteins membrane in preparation roles of acrosomal

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Asian Journal of Andrology 2015年第4期17卷 574-582页

作者： Nongnuj Tanphaichitr kessiri kongmanas Hathairat kruevaisayawan Arpornrad Saewu Clarissa Sugeng Jason fernandes Puneet Souda Jonathan B Angel k.m f faull R John Aitken Julian Whitelegge Daniel Hardy Trish Berger mark Baker Chronic Disease Program Ottawa Hospital ResearchInstitute Ottawa Ontario Canada Department ofObstetrics and Gynaecology University of OttawaOntario Canada Department of Biochemistry Microbiology and Immunology University of OttawaOntario Canada Department of Anatomy Faculty ofMedical Sciences Naresuan University PhitsanulokThailand Division of Infectious Diseases OttawaHospital - General Campus Ottawa Ontario Canada Pasarow mass Spectrometry Laboratory Universityof California Los Angeles California USA TheARC Centre of Excellence in Biotechnology andDevelopment School of Environmental and LifeSciences University of Newcastle Callaghan NewSouth Wales Australia Department of Cell Biologyand Biochemistry Health Sciences Center Texas TechUniversity Texas USA Department of Animal ScienceUniversity of California Davis California USA

The interaction of sperm with the egg＇s extracellular matrix, the zona pellucida （ZP） is the first step of the union between male and female gametes. The molecular mechanisms of this process have been studied for the past six decades with the results obtained being both interesting and confusing. In this article, we describe our recent work, which attempts to address two lines of questions from previous studies. first, because there are numerous ZP binding proteins reported byvarious researchers, how do these proteins act together in sperm-ZP interaction？ Second, why do a number of acrosomal proteins have ZP affinity？ Are they involved mainly in the initial sperm-ZP binding or rather in anchoring acrosome reacting/reacted spermatozoa to the ZP？ Our studies reveal that a number of ZP binding proteins and chaperones, extracted from the anterior sperm head plasma membrane, coexist as high molecular weight （HmW） complexes, and that these complexes in capacitated spermatozoa have preferential ability to bind to the ZP. Zonadhesin （ZAN）, known as an acrosomal protein with ZP affinity, is one of these proteins in the HmW complexes. Immunoprecipitation indicates that ZAN interacts with other acrosomal proteins, proacrosin/acrosin and sp32 （ACRBP）, also present in the HmW complexes. Immunodetection of ZAN and proacrosin/acrosin on spermatozoa further indicates that both proteins traffic to the sperm head surface during capacitation where the sperm acrosomal matrix is still intact, and therefore they are likely involved in the initial sperm-ZP binding step.

关键词： SPERm CAPACITATION ANDSPERm-ZONA PELLUCIDAINTERACTION- BACkGROUND ANDCONfUSION IN THE fIELDS

Numerical investigation of a double-junction a:Si Ge thin-film solar cell including the multi-trench region

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Journal of Semiconductors 2015年第6期36卷 53-57页

作者： k.kacha f.Djeffal H.ferhati D.Arar m.meguellati LEA Department of Electronics University of Batna LEPCm University of Batna

We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new multi-trench region in the intrinsic layer, in order to modulate the total resistance of the solar cell. Based on 2- D numerical investigation and optimization of amorphous SiGe double-junction （a-Si：H/a-SiGe：H） thin film solar cells, in the present paper numerical models of electrical and optical parameters are developed to explain the impact of the multi-trench technique on the improvement of the double-junction solar cell electrical behavior for high performance photovoltaic applications. In this context, electrical characteristics of the proposed design are analyzed and compared with conventional amorphous silicon double-junction thin-film solar cells.

关键词： amorphous efficiency SiGe thin-film solar cell multi-trench

Interactive data styling and multifocal visualization for a multigrid web-based Digital Earth

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International Journal of Digital Earth 2021年第3期14卷 288-310页

作者： m.J.Sherlock.m.Hasan f.f.Samavati Department of Computer Science University of CalgaryCalgaryCanada

Globe-based Digital Earth(DE)is a promising system that uses 3D models of the Earth for integration,organization,processing,and visualization of vast multiscale geospatial *** growing size and scale of geospatial datasets present significant obstacles to interactive viewing and meaningful visualizations of these DE *** address these challenges,we present a novel web-based multiresolution DE system using a hierarchical discretization of the globe on both server and client *** presented web-based system makes use of a novel data encoding technique for rendering large multiscale geospatial datasets,with the additional capability of displaying multiple simultaneous *** the data needed for the current views and scales are encoded and *** leverage the power of GPU acceleration on the client-side to perform real-time data rendering and dynamic *** rendering of multiple views allows us to support multilevel focus+context visualization,an effective approach to navigate through large multiscale global *** client–server interaction as well as the data encoding,rendering,styling,and visualization techniques utilized by our presented system contribute toward making DE more accessible and informative.

关键词： Digital Earth Discrete Global Grid System data integration data fusion multilevel focus+context visualization spatial resolution context awareness

modified Burzynski criterion with non-associated flow rule for anisotropic asymmetric metals in plane stress problems

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Applied mathematics and mechanics(English Edition) 2015年第3期36卷 303-318页

作者： f.mOAYYEDIAN m.kADkHODAYAN Department of mechanical Engineering Ferdowsi University of Mashhad

The Burzynski criterion is developed for anisotropic asymmetric metals with the non-associated flow rule （NAfR） for plane stress problems. The presented pressure depending on the yield criterion can be calibrated with ten experimental data, i.e., the tensile yield stresses at 0°, 45°, and 90°, the compressive yield stresses at 0°, 15°, 30°, 45°, 75°, and 90° from the rolling direction, and the biaxial tensile yield stress. The corresponding pressure independent plastic potential function can be calibrated with six experimental data, i.e., the tensile R-values at 0°, 15°, 45°, 75°, and 90° from the rolling direction and the tensile biaxial R-value. The downhill simplex method is used to solve these ten and six high nonlinear equations for the yield and plastic potential functions, respectively. The results show that the presented new criterion is appropriate for anisotropic asymmetric metals.

关键词： modified Burzynski criterion pressure dependent asymmetric metal down-hill simplex method non-associated flow rule (NAfR)

A passive-biped model with multiple routes to chaos

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Acta mechanica Sinica 2011年第2期27卷 277-284页

作者： f. farshimi m. Naraghi Department of mechanical Engineering Amirkabir University of Technology Tehran Iran

This paper presents a new passive-biped model consisting of a simplest walking model beneath an upper body, with no kinematic constraint. The upper body is attached to the legs with a linear torsional spring. The model is a passive dynamic walker, so it walks down a slope without energy input. The governing equations of motion are derived and simulated for the parameter analysis purposes. Simulation results reveal some different routes to chaos that have not been observed in previous models.

关键词： Passive-biped Routes to chaos Upper body Bifurcation

Effect of ultrasonic irradiation and /or halogenation on the catalytic performance of γ-Al_2O_3 for methanol dehydration to dimethyl ether

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燃料化学学报 2013年第9期41卷 1077-1084页

作者： Sameh m.k.Aboul-fotouh Ain Shams University Faculty of EducationChemistry DepartmentRoxyCairo 11566Egypt

Dimethyl ether(DmE) is amongst one of the most promising alternative,renewable and clean fuels being considered as a future energy *** this study,the comparative catalytic performance of the halogenated γ-Al 2 O 3 prepared from two halogen precursors(ammonium chloride and ammonium fluoride) is *** impact of ultrasonic irradiation was evaluated in order to optimize both the halogen precursor for the production of DmE from methanol in a fixed bed *** catalysts were characterized by SEm,XRD,BET and NH *** reaction conditions where the temperature ranged from 200 to 400 ℃ with a WHSV = 15.9 h-1was found that the halogenated catalysts showed higher activity at all reaction ***,the halogenated alumina catalysts prepared under the effect of ultrasonic irradiation showed higher performance of γ-Al 2 O 3 for DmE *** chlorinated γ-Al 2 O 3 catalysts showed a higher activity and selectivity for DmE production than fluorinated versions.

关键词：化学原理方法化学动力学

Experimental Investigation of Separation and Transition Processes on a High-Lift Low-Pressure Turbine Profile Under Steady and Unsteady Inflow at Low Reynolds Number

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Journal of Thermal Science 2010年第1期19卷 26-33页

作者： Satta f Simoni D Ubaldi m Zunino P Bertini f DImSET-Università di Genova Via Montallegro 1I-16145 GenovaItaly Avio R&D V.I Maggio99 I-10040 Rivalta(TO)-Italy

The effects induced by the presence of incoming wakes on the boundary layer developing over a high-lift low-pressure turbine profile have been investigated in a linear cascade at *** tested Reynolds number is 70000,typical of the cruise operating *** results of the investigations performed under steady and unsteady inflow conditions are *** unsteady investigations have been performed at the reduced frequency of f+=0.62,representative of the real engine operating *** aerodynamic loadings as well as boundary layer velocity profiles have been measured to survey the separation and transition *** analysis has been also performed to better understand the phenomena associated with the transition process under steady *** the unsteady case,a phase-locked ensemble averaging technique has been employed to reconstruct the time-resolved boundary layer velocity distributions from the hot-wire instantaneous signal *** ensemble-averaging technique allowed a detailed analysis of the effects induced by incoming wakes-boundary layer interaction in separation ***-resolved results are presented in terms of mean velocity and unresolved unsteadiness time-space plots.

关键词： boundary layer separation boundary layer transition wake-boundary layer interaction high-liftprofile low-pressure turbine