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Journal of magnesium and Alloys 2022年第10期10卷 2761-2774页

作者： m.Passing C.Pistidda G.Capurso J.Jepsen O.metz m.Dornheim T.Klassen Institute of Hydrogen Technology Helmholtz-Zentrum HereonMax-Planck-Straße 1 DGeestacht 21502Germany Institute of materials Technology Helmut Schmidt UniversityHolstenhofweg 85 DHamburg 22043Germany

With the increased use of renewable energy sources,the need to store large amounts of energy will become increasingly important in the near future.A cost efficient possibility is to use the reaction of recycled mg waste with hydrogen as thermo-chemical energy *** to the high reaction enthalpy,the moderate pressure and appropriate temperature conditions,the broad abundance and the recyclability,the mg/Al alloy is perfectly suitable for this *** further development of a previous work,in which the performance of recycled mg/Al waste was presented,a kinetic model for hydro-and dehydrogenation is derived in this *** and pressure dependencies are determined,as well as the rate limiting step of the *** experiments are carried out in an autoclave with a scaled-up powder mass,which is also used to validate the model by simulating the geometry with the scaled-up experiments at different conditions.

关键词： Thermo-chemical energy storage Hydrogen storage metal hydride magnesium based waste Recycling

Influence of Al_2O_3 particle pinning on thermal stability of nanocrystalline Fe

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Journal of materials Science & Technology 2018年第4期34卷 599-604页

作者： G.B.Shan Y.Z.Chen m.m.Gong H.Dong B.Li F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Second-phase particle pinning has been well known as a mechanism impeding grain boundary （GB） migration, and thus, is documented as an efficient approach for stabilizing nanocrystalline （NC） materials at elevated temperatures. The pinning force exerted by interaction between small dispersed particles and GBs strongly depends on size and volume fraction of the particles. Since metallic oxides, e.g. Al2O3, exhibit great structural stability and high resistance against coarsening at high temperatures, they are expected as effective stabilizers for NC materials. In this work, NC composites consisting of NC Fe and Al2O3 nanoparticIes with different amounts and sizes were prepared by high energy ball milling and annealed at various temperatures （Tann） for different time periods （tann）. microstructures of the ball milled and annealed samples were examined by X-ray diffraction and transmission electron microscopy. The results show that the addition of Al2O3 nanoparticles not only enhances the thermal stability of NC Fe grains but also reduces their coarsening rate at elevated temperatures, and reducing the particle size and/or increasing its amount enhance the stabilizing effect of the Al2O3 particles on the NC Fe grains.

关键词： Iron Nanocrystalline materials Ball milling Zener pinning Grain growth Thermal stability

Turbine Blade Boundary Layer Separation Suppression via Synthetic Jet: an Experimental and Numerical Study

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Journal of Thermal Science 2012年第5期21卷 404-412页

作者： Bernardini C. Carnevale m. manna m. martelli F. Simoni D. Zunino P. Università degli Studi di Firenze Firenze Italy Università degli Studi di Napoli Federico Ⅱ Napoli Italy Università degli Studi di Firenze FirenzeItaly Università degli Studi di Genova Genova Italy

The present paper focuses on the analysis of a synthetic jet device (with a zero net massflow rate) on a separated boundary layer. Separation has been obtained on a flat plate installed within a converging-diverging test section specifically designed to attain a local velocity distribution typical of a high-lift LPT blade. Both experimental and numerical investigations have been carried out. Unsteady RANS results have been compared with experiments in terms of time-averaged velocity and turbulence intensity distributions. Two different Reynolds number cases have been investigated, namely Re = 200,000 and Re = 70,000, which characterize low-pressure turbine operating conditions during take-off/landing and cruise. A range of synthetic jet aerodynamic parameters (Strouhal number and blowing ratio) has been tested in order to analyze the features of control-separated boundary layer interaction for the aforementioned Reynolds numbers.

关键词： Synthetic Jet Separated Flow Active Flow Control Unsteady Flow Ultra High Lift LPT.

Thermal behaviour analysis in a porcelainhoused ZnO surge arrester by computer simulations and thermography

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High Voltage 2019年第3期4卷 173-177页

作者： Arthur F.Andrade Edson G.Costa Josué m.B.Fernandes Helem m.m.Alves Cícero R.C.Amorim Filho Centre of Electrical Engineering and Informatics Federal University of Campina GrandeCampina GrandeBrazil Department of Electrical Engineering Federal University of Campina GrandeCampina GrandeBrazil

In this article,an analysis of heat transfer in a porcelain-housed ZnO surge arrester is *** to the fact that ZnO-based surge arresters are key components for protection and reliability of electrical systems,it is necessary to seek techniques to assure correct *** porcelain-housed arresters,the air gap leads to an increased thermal resistance between the ambient and the varistor ***,a thermal analysis must consider convection and radiation heat transfer mechanisms,besides heat *** study proposes the use of computational simulations in combination with thermography as a tool for a temperature-based estimation of the varistor *** the analysis,temperature rise tests were performed in a 69-kV ceramic-housed arrester to measure material emissivity and produce data to fit the simulated ***,the thermal response of the surge arresters subject to an impulsive energy input was *** simulations allow to relate varistors temperature and housing temperature with regard to a specified amount of dissipated *** obtained results show that the used technique can be an effective method for arrester monitoring and may allow to define assessing criteria for a porcelain-housed arrester based on housing temperature measurements.

关键词： behaviour specified ambient

Systematic study of rotational energy formulae for superdeformed bands in La and Ce isotopes

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Chinese Physics C 2017年第12期41卷 55-66页

作者： Honey Sharma H.m. mittal Dr. B.R. Ambedkar National Institute of Technology Jalandhar 144011 India

The experimental rotational spectra of superdeformed（SD） bands of 130La, 131Ce（1,2）, 132Ce（1,2,3） and133 Ce（1,2,3） in the A～130 mass region are systematically analyzed with the four parameter formula, power index formula, nuclear softness formula, and VmI model. It is observed that out of all the formulae, the four parameter formula suits best for the study of the 130La, 131Ce（1,2）, 132Ce（2,3） and 133Ce（1,2,3） SD bands. The four parameter formula works efficiently in determining the band head spin of the 130La, 131Ce（1,2） 132Ce（2,3） and 133Ce（1,2,3） SD bands. Good agreement is seen between the calculated and observed transition energies whenever the accurate spin is assigned. In 132Ce（1）, the power index formula is found to work better than the other three formulae. The dynamic moment of inertia is also calculated for all the formulae and its variation with the rotational frequency is investigated.

关键词： superdeformed bands four parameter formula power index formula nuclear softness formula VmI model

Growth performance,haematology,serum biochemistry and meat quality characteristics of Japanese quail(Coturnix coturnix japonica)fed canola meal-based diets

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Animal Nutrition 2018年第1期4卷 37-43页

作者： Caven m.mnisi Victor mlambo Department of Animal Science School of Agricultural SciencesFaculty of AgricultureScience and TechnologyNorth-West University Food Security and Safety Niche Area Faculty of AgricultureScience and TechnologyNorth-West University

The present study investigated the effect of partial replacement of soybean meal(Glycine max) with canola meal(Cm)(Brassica napus) on the growth performance,haematology,serum biochemistry and meat quality characteristics of female Japanese quails in a 35-day feeding *** hundred and forty6-week-old quails 158.28 ± 11.919 g were randomly allocated to 5 isonitrogenous and isoenergetic experimental diets: control diet(Cm0; with no Cm inclusion); Cm0 with 2.5%(Cm25),5.0%(Cm50),12.5%(Cm125) and 17.5%(Cm175) soybean meal replaced with *** weekly gain(AWG) and feed conversion efficiency(FCE) were ***,serum biochemistry,carcass traits and meat quality parameters were determined at *** fed Cm175 had the lowest(P mong the other 4 *** dietary effects on AWG,FCE and haematological parameters were *** biochemical parameters were not influenced by diets with the exception of alkaline phosphatase(ALP),where quails fed Cm25 had higher ALP(161.0 U/L) than those fed Cm0(37.25 U/L).Quails fed Cm25 had the highest chroma(7.39) while those fed Cm125 had the lowest(3.58) at 24 h *** had no influence(P > 0.05) on cooking losses and peak positive force of quail *** was concluded that Cm can replace soybean in quail diets up to 12.5% without compromising growth performance,health and quality of *** levels beyond 12.5% promoted poor voluntary feed intake and thus may require feed additives to enhance utilization.

关键词： Japanese quail Haematology meat Feed intake Canola meal

Superhydrophobic surface of mg alloys:A review

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Journal of magnesium and Alloys 2018年第1期6卷 59-70页

作者： m.Yeganeh N.mohammadi Department of materials Science and Engineering Faculty of EngineeringShahid Chamran University of AhvazAhvazIran

In the present review,the formation of superhydrophobic(SHP)structures on the surface of mg alloys was *** methods including hydrothermal technique,chemical and electrochemical deposition,conversion and polymer coating,and etching routes were *** superhydrophobicity could form on the surface of mg alloys by the application of different chemical,electrochemical,and physical methods followed by the immersion of these alloys in the solution containing modifying agents including fatty acids or long-chain *** formed morphology,composition,and contact angle were reported and the effect of synthesis route on these characteristics was reviewed.

关键词： mg alloys Superhydrophobic surfaces Chemical deposition Electrochemical coating Conversion coating Polymer coating Etching

microstructure and Fracture Behavior of 316L Austenitic Stainless Steel Produced by Selective Laser melting

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Journal of materials Science & Technology 2016年第8期32卷 738-744页

作者： R.Casati J.Lemke m.Vedani Department of mechanical Engineering Politecnico di Milano

Selective laser melting is an additive manufacturing method based on local melting of a metal powder bed by a high power laser beam. Fast laser scans are responsible for severe thermal gradients and high cooling rates which produce complex hydrodynamic fluid flow. These phenomena affect crystal growth and orientation and are believed to be the cause of material spattering and microstructural defects, e.g. pores and incompletely melted particles. In this work, the microstructure and texture of 316L bars built along two different orientations and the effect of different distribution of defects on their mechanical response and failure mechanisms were investigated. Partially molten powder particles are believed to be responsible for the scattering in elongation to failure, reduced strength, and premature failure of vertical samples.

关键词： AISI 316L Additive manufacturing Selective laser melting microstructural analysis Fracture behavior

A CASE FOR SERVICE SYSTEmS ENGINEERING

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Systems Science and Systems Engineering 2003年第1期12卷 13-38页

作者： James m.TIEN Daniel BERG Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute Troy New York 12110-3590U.S.A.Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute TroyNew York 12110-3590U.S.A.

A case is made for further developing a branch of systems engineering that focuses on problems and issues which arise in the service sector. We promulgate this special focus not only because of the size and importance of the service sector but also because of the unique opportunities that systems engineering can exploit in the design and joint production and delivery of services. We begin by considering the economic, technological and demographic contexts within which the service sector has flourished; we then address both services, especially emerging services, and systems engineering, followed by a discussion of how to advance the field of service systems engineering, and concluding with several remarks. In particular, a number of service systems engineering methods are identified to enhance the design and production/delivery of services, especially taking advantage of the unique features that characterize services - namely, services, especially emerging services, are information-driven, customer-centric, e-oriented, and productivity-focused.

关键词： Service sector systems engineering information technology decision technologies customer-centric productivity

Interplay between strong Allee effect, harvesting and hydra effect of a single population discrete-time system

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International Journal of Biomathematics 2016年第1期9卷 65-89页

作者： Debaldev Jana Elsayed m. Elsayed Ecological modelling LaboratoryDepartment of Zoology Visva-Bharati University Santiniketan 731235 India mathematics DepartmentFaculty of Science King Abdulaziz UniversityP. O. Box 80203 Jeddah 21589 Saudi Arabia Department of mathematicsFaculty of Science Mansoura University Mansoura 35516 Egypt

The dynamics of a single population with non-overlapping generations can be described deterministically by a scalar difference equation in this study. A discrete-time Beverton- Holt stock recruitment model with Allee effect, harvesting and hydra effect is proposed and studied. model with strong Allee effect results from incorporating mate limitation in the Beverton-Holt model. We show that these simple models exhibit some interesting （and sometimes unexpected） phenomena such as the hydra effect, sudden collapses and essential extinction. Along with this, harvesting is a socio-economie issue to continue any system generation after generation. Different dynamical behaviors for these situations have been illustrated numerically also. The biological implications of our analytical and numerical findings are discussed critically.

关键词： Beverton-Holt model hydra effect harvesting Allee effect.