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CARBIDE FORMATIOn In AUSTEMPERED DUCTILE IROn ALLOYED WITH nICKEL AnD COPPER

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 190-194页

作者： FA n Zhikang (Xi’an University of Technology, China)SMALLMAnRE(University of Birmingham,UK) Xi'an Univ of Technology Xi'an China

Carbide formation in austempered ductile iron (ADI) alloyed with ni and Cu has been studied by use of TEM. The results show that η carbide precipitates in the bainitic ferrite when austempered at 350℃.for 6h, but no carbide was found at the austenite/.ferrite interfaces. When austempered at 300℃, two kinds of. s carbides appear in the bainitic ferrite when austempering time reached I h, and X carbide also precipitates at the austenite /ferrite interfaces when austempering time was extended up to 6h. The bainitic. ferrite and the retained austenite follow the nishiyama- Wasserman relationship,

关键词： carbide austempered ductile iron

High-temperature thermodynamics of silver:Semi-empirical approach

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Chinese Physics B 2017年第11期26卷 400-407页

作者： R H Joshi B Y Thakore P R Vyas A R Jani n K Bhatt Department of Physics Sardar Patel University Department of Physics School of Sciences Gujarat University Sardar Patel Center for Science and Technology Department of Physics M.K.Bhavnagar University

We report high-temperature thermodynamics for fcc silver by combining ab initio phonon dynamics to empirical quadratic temperature-dependent term for anharmonic part of Helmholtz free energy. The electronic free energy is added through an interpolation scheme, which connects ambient condition free electron gas model to Thomas-Fermi *** present study shows good agreement with experimental and reported findings for several thermal properties, and the discrepancy observed in some caloric properties is addressed. The decreases in the product of volume thermal expansion coefficient and isothermal bulk modulus and in the constant volume anharmonic lattice specific heat at high temperature are the clear evidences of proper account of anharmonicity. The present study also reveals that T-2-dependent anharmonic free energy is sufficient for correct evaluation of thermal pressure and conventional Grüneisen parameter. We observe that the intrinsic phonon anharmonicity starts dominating above characteristic temperature, which is attributed to higher order anharmonicity and can be related to higher order potential derivatives. We conclude that the uncorrelated and largeamplitude lattice vibrations at high temperature raise dominating intrinsic thermal stress mechanism, which surpasses the phonon-anharmonism and requires future consideration.

关键词： thermodynamics anharmonicity Grüneisen parameter silver

Ezrin： a regulator of actin microfilaments in ce unctions of the rat testis

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Asian Journal of Andrology 2015年第4期17卷 653-658页

作者： n Ece Gungor-Orduer Ciler Celik-Ozenci C Yan Cheng The Mary M. Wohlford Laboratory for Male Contraceptive Research Center for Biomedical Research Population Council New York USA Department of Histology andEmbryology Faculty of Medicine Akdeniz University Antalya Turkey.

Ezrin, radixin, moesin and merlin （ERM） proteins are highly homologous actin-binding proteins that share extensive sequence similarity with each other. These proteins tether integral membrane proteins and their cytoplasmic peripheral proteins （e.g., adaptors, nonreceptor protein kinases and phosphatases） to the microfilaments of actin-based cytoskeleton. Thus, these proteins are crucial to confer integrity of the apical membrane domain and its associated junctional complex, namely the tight junction and the adherens junction. Since ectoplasmic specialization （ES） is an F-actin-rich testis-specific anchoring junction-a highly dynamic ultrastructure in the seminiferous epithelium due to continuous transport of germ cells, in particular spermatids, across the epithelium during the epithelial cycle-it is conceivable that ERM proteins are playing an active role in these events. Although these proteins were first reported almost 25 years and have since been extensively studied in multiple epithelia/endothelia, few reports are found in the literature to examine their role in the actin filament bundles at the ES. Studies have shown that ezrin is also a constituent protein of the actin-based tunneling nanotubes （TnT） also known as intercellular bridges, which are transient cytoplasmic tubular ultrastructures that transport signals, molecules and even organelles between adjacent and distant cells in an epithelium to coordinate cell events that occur across an epithelium. Herein, we critically evaluate recent data on ERM in light of recent findings in the field in particular ezrin regarding its role in actin dynamics at the ES in the testis, illustrating additional studies are warranted to examine its physiological significance in spermatogenesis.

关键词： blood-testis barrier ectoplasmic specialization ezrin spermatogenesis testis

Plinthite and Its Associated Evolutionary Forms in Soils and Landscapes:A Review

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Pedosphere 2014年第2期24卷 153-166页

作者： P.n.EZE T.K.UDEIGWE M.E.MEADOWS Department of Environmental & Geographical Science University of Cape Town Department of Plant and Soil Science Texas Tech University

At elevated temperature regimes and abundant precipitation, mobilization and accretion of weathered iron oxides are promoted especially in a reduced environments in the tropics. This may lead to the formation of plinthite, which hardens irreversibly upon repeated wetting and drying to form petroplinthite. The need for this review stems from the seemingly dearth of information on the subject and a need to clarify different terms used in describing plinthite. We review various research works on plinthite and its associated pedogenic forms in the tropics. Furthermore, we proffer recommendations as to the most appropriate land use management practices that could help minimise the environmental and agronomic problems associated with plinthite and its related pedogenic forms. Parent material, temperature, seasonality and geomorphology are critical factors that influence soil water regime which in turn affect the pedogenesis of plinthite. Soil pH and mineralogy are additional factors that could also promote plinthite formation. Fossil plinthic soils are potential proxies for palaeoenvironmental reconstruction. Measures used in the management of plinthic soils include mechanically breaking the hardpans and the use of organic and inorganic amendments to modify the structure and chemistry of the soils. Avoidance of practices that would predispose soils to erosion would also prevent plinthization. We call for the relinquishment of the term ＂[aterite＂ which is a generM term for all forms of iron oxide-enriched earthy materials as used for plinthite. Plinthic horizon should also be incorporated into the United States Department of Agriculture Soil Taxonomy in view of its growing importance in soils.

关键词： agronomy pedogenesis petroplinthite soil taxonomy tropics

D-Dimensional Dirac Equation for Energy-Dependent Pseudoharmonic and Mie-type Potentials via SUSYQM

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Communications in Theoretical Physics 2014年第4期61卷 436-446页

作者： A.n.Ikot H.Hassanabadi E.Maghsoodi S.Zarrinkamar Theoretical Physics Group Department of PhysicsUniversity of Uyo Department of Basic Sciences Shahrood BranchIslamic Azad University Civil Engineering Group Alaodoleh Semnani Institute of Higher Education

We investigate the approximate solution of the Dirac equation for energy-dependent pseudoharmonic and Mie-type potentials under the pseudospin and spin symmetries using the supersymmetry quantum mechanics. We obtain the bound-state energy equation in an analytical manner and comment on the system behavior via various figures and tables.

关键词： Dirac equation spin symmetry pseudospin symmetry energy-dependent potential pseudohar-monic potential Mie-type potential

Effect of nodule count and austempering heat treatment on segregation behavior of alloying elements in ductile cast iron

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China Foundry 2016年第3期13卷 217-222页

作者： E.Akbarzadeh Chiniforush n.Iranipour S.Yazdani Faculty of Materials Engineering Sahand University of Technology Deakin University Institute for Technology Research and Innovation

The equilibrium partition ratio, k, has been measured for Mn, Mo, Si, ni and Cu in a ductile iron with composition(wt.%): 3.45 C, 0.25 Mn, 0.25 Mo, 2.45 Si, 0.5ni and 0.5Cu with different nodule counts obtained from different section sizes of13, 25, 75 mm in the as cast, austenitized(at 870 °C for times 1, 4 and 6 hours) and austempered(at 375 °C for times 1 to 1,440 min) samples. Results show that Mn and Mo segregate positively at cell boundaries, but Si, ni and Cu concentrate in an inverse manner in the vicinity ofgraphite nodules and there is a depletion ofthese elements at cell boundaries. Segregation curves for ni and Cu are more smooth than for Si. Carbide formation has been observed at cell boundaries. Based on the results, the partition ratios for all elements decrease with increasing the nodule count. More carbide with coarser morphology has been observed in the microstructure with a lower nodule count. Austenitization for a longer time can decrease partition ratio, but cannot eliminate it entirely. Increasing the austenitization temperature has the same effect. Austenitizing parameters have no significant effect on carbides volume fraction. The kinetics ofaustempering is faster in higher nodule counts and subsequently better mechanical properties including higher ductility, strength and toughness have been observed for all austempering conditions studied.

关键词： segregation ductile iron austenitization austempering

Energy management of micro renewable energy source and electric vehicles at home level

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Journal of Modern Power Systems and Clean Energy 2017年第6期5卷 979-990页

作者： Ibán JUnQUERA MARTínEZ Javier GARCíA-VILLALOBOS Inmaculada ZAMORA Pablo EGUíA Department of Electrical Engineering University of the Basque CountryLeioaSpain

As renewable energy source(RES)tend to be integrated more and more at home and electric vehicles(EVs)take a greater share in the personal automobile market,users see a chance to charge their EVs by *** this context,this paper presents a review about opportunities and challenges needed to be overcome by the EV users to implement a vehicle to home system in their homes,as well as the integration of *** practical scenarios are presented,with different demand profiles,by integrating renewable energy that could be used to charge the EV.

关键词： Plug-in electric vehicles(PEV) Vehicle to home(V2H) Micro renewable energy source(micro-RES) Challenges

Effects of noise on fishes: What we can learn from humans and birds

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Integrative Zoology 2015年第1期10卷 29-37页

作者： Robert J.DOOLInG Marjorie R.LEEK Arthur n.POPPER Department of Psychology University of MarylandCollege ParkMarylandUSA national Center for Rehabilitative Auditory Research PortlandVA Medical CenterPortlandOregonUSA Department of Biology University of MarylandCollege ParkMarylandUSA

In this paper we describe the masking of pure tones in humans and birds by manmade noises and show that similar ideas can be applied when considering the potential effects of noise on fishes,as well as other aquatic *** from many studies on humans and birds,both in the field and in the laboratory,show that published critical ratios can be used to predict the masked thresholds for pure tones when maskers consist of complex manmade and natural *** argue from these data that a single,simple measure,the species critical ratio,can be used to estimate the effect of manmade environmental noises on the perception of communication and other biologically relevant *** also reason that if this principle holds for species as diverse as humans and birds,it probably also applies for all other vertebrates,including fishes.

关键词： behavior communication manmade noise masking sound

Cellulose Fibre from Schinus molle and Its Characterization

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Journal of Renewable Materials 2022年第10期10卷 2593-2606页

作者： Abir Razzak Faten Mannai Ramzi Khiari Younes Moussaoui Mohamed n.Belgacem Laboratory for the Application of Materials to the Environment Waterand Energy(LR21ES15)Faculty of Sciences of GafsaUniversity of GafsaGafsa2112Tunisia Faculty of Sciences of Gafsa University of GafsaGafsa2112Tunisia Laboratory of Environmental Chemistry and Cleaner Process(LR21ES04) University of MonastirMonastir5019Tunisia Higher Institute of Technological Studies(ISET)of Ksar-Hellal Ksar-Hellal5070Tunisia University of Grenoble Alpes CNRSGrenoble INPLGP2GrenobleF-38000France Organic Chemistry Laboratory(LR17ES08) Faculty of Sciences of SfaxUniversity of SfaxSfax3029Tunisia

The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil *** this perspective,the main objective of this work is the extraction and the characterization of natural lignocellulosic fibers from the Schinus *** cellulose fibre extraction was investigated employing conditions of alkali *** the alkaline steps,a bleaching treatment was done and let to a yield about 45%pure *** identification of the chemical composition of Schinus molle reveals that this raw material contains a high level of biopolymers with a cellulose rate of 53.2%.Extracted cellulose fibers have been characterized by several techniques such as scanning electron microscopy,Fourier transform infrared,X-ray diffraction,Morfi,and by the determination of their degree of ***-IR results confirm the purity of the cellulosic fibers,and XRD analysis reveals that the crystallinity increases after the delignification and bleaching treatments.

关键词： Schinus molle cellulose alkaline treatment morphological studies