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Development，Application，Markets，and　Patent　Situation　of　Magnetostrictive　TERFENoL－D

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Journal of Rare Earths 1995年第4期13卷 295-301页

作者： McMasters, o.D. ETREMA Products Inc. 2500 North Loop Drive Ames Iowa 50010

The development of the giant magnetostrictive rare earth-iron materials is reported from their discovery in the early 1970's to their present use in transducer and sensor applications. Fifteen broad market areas, ranging from miniature devices in the medical industry to high powder sonar and seismic sources have been identified. A world-wide customer base in these high technology fields has been established and the superior properties of these materials are responsible for the rapid growth of the magnetostrictive transducer industries. The critical design criteria that lead to efficient devices are reported and the performance of several of these products is presented. The key patents associated with these giant magnetostrictive materials and devices using these materials are reviewed. The present and future of these technologies in reference to commercialization, market growth and the impact on the many transduction industries are discussed. (Author abstract) 9 Refs.

关键词： Magnetostrictive Situation Patent TERFENoL and Development Application

Breakage of drops and bubbles in a stirred tank： A review ofexperimental studies

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Chinese Journal of Chemical Engineering 2017年第6期25卷 698-711页

作者： Basim o. Hasan Department of Chemical Engineering Technical University of Berlin 6ermany Department of Chemical Engineering AI-Nahrain University lraq

The rate of breakage of drops and bubbles(fluid particles) in stirred systems is of great consequence on mass,heat, and momentum transport phenomena. Therefore, over the years, the topic has gained a considerable attention from the researchers to study and characterize this phenomenon. In present work, the experimental studies of breakage phenomenon in a stirred tank in the last four decades were reviewed. The review highlighted the investigated experimental conditions and the major findings concerning the breakage mechanism and the effect of operating conditions. The discrepancy and contradictions of the outcomes of those studies were specified and discussed. Experimental observations and conclusions concerning the breakage characterization parameters,such as deformation, breakage probability, breakage time, and breakage location were presented and commented on. Possible future refinements and prospective were recommended. The review indicated that there are clear discrepancies and contradictions between previous studies regarding the effect of some operating parameters and the values of breakage time, breakage probability, number of daughter particles, and breakage location relative to the impeller. In addition, there are still many scientific gaps that need to be studied and characterized in future by overcoming specific experimental difficulties and uncertainties.

关键词： Drop Bubble Breakage Stirred tank Review Breakage rate

Hydrodynamics of marine and offshore structures

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Journal of Hydrodynamics 2014年第6期26卷 835-847页

作者： FALTINSEN o.M. Centre for Autonomous Marine operations and Systems (AMoS) Department of Marine Technology

An overview of hydrodynamic problems related to the broad variety of ships and sea structures involved in transportation, oil and gas exploration and production, marine operations, recovery of oil-spill, renewable energy, infrastructure and aquaculture is given. An approximate hydroelastic model for wave and current induced response of a floating fish farm with circular plastic collar and net cage is discussed. Weakly nonlinear potential-flow problems such as slow-drift motions and stationkeeping, springing of ships and ringing are given special attention. Body-fixed coordinate system is recommended in weakly nonlinear potential-flow analysis of bodies with sharp corners. Dynamic ship instabilities, Mathieu-type instabilities, chaos and two-phase flow involving interface instabilities are discussed. It is advocated that slamming must be coupled with structural mechanics in order to find important time scales of the many physical effects associated with slamming and that both water entry and exit matter in describing the global wetdeck slamming effects. Further, sloshing-induced slamming in prismatic LNG tanks is perhaps the most complicated slamming problem because many fluid mechanic and thermodynamic parameters as well as hydroelasticity may matter.

关键词： hydroelastic model slow-drift motion instability slamming

Comparison of Impact Properties for Carbon and Low Alloy Steels

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Journal of Materials Science & Technology 2011年第10期27卷 931-936页

作者： o.H.Ibrahim Metallurgy Dept. Nuclear Research CentreAtomic Energy Authority

The impact properties of hot rolled carbon steel （used for the manufacture of reinforcement steel bars） and the quenched ＆ tempered （Q＆T） low alloy steel （used in the pressure vessel industry） were determined. The microstructure of the hot rolled carbon steel contained ferrite/pearlite phases, while that of the quenched and tempered low alloy steel contained bainite structure. Impact properties were determined for both steels by instrumented impact testing at temperatures between -150 and 200℃. The impact properties comprised total impact energy, ductile to brittle transition temperature, crack initiation and propagation energy, brittleness transition temperature and cleavage fracture stress. The Q＆T low alloy steel displayed much higher resistance to ductile fracture at high test temperatures, while its resistance to brittle fracture at low test temperatures was a little higher than that of the hot rolled carbon steel. The results were discussed in relation to the difference in the chemical composition and microstructure for the two steels.

关键词： Ferritic/pearlitic steel Bainitic steel Impact properties

High-temperature mechanical properties of aluminium alloys reinforced with titanium diboride (TiB_2) particles

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Rare Metals 2011年第2期30卷 200-205页

作者： J.ooro Ingeniería y Ciencia de los Materiales ETSI IndustrialesUniversidad Politécnica de Madridc/José Gutiérrez Abascal2.28006 MadridSpain

The physical and mechanical properties of metal matrix composites were improved by the addition of reinforcements. The mechanical properties of particulate-reinforced metal-matrix composites based on aluminium alloys （6061 and 7015） at high temperatures were studied. Titanium diboride （TiB2） particles were used as the reinforcement. All the composites were produced by hot extrusion. The tensile properties and fracture characteristics of these materials were investigated at room temperature and at high temperatures to determine their ultimate strength and strain to failure. The fracture surface was analysed by scanning electron microscopy. TiB2 particles provide high stability of the alumin- ium alloys （6061 and 7015） in the fabrication process. An improvement in the mechanical behaviour was achieved by adding TiB2 particles as reinforcement in both the aluminium alloys. Adding TiB2 particles reduces the ductility of the aluminium alloys but does not change the microscopic mode of failure, and the fracture surface exhibits a ductile appearance with dimples formed by coalescence.

关键词： metal-matrix composites aluminium high-temperature properties titanium diboride

Cracking Susceptibility After Post-Weld Heat Treatment in Haynes 282 Nickel Based Superalloy

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 747-753页

作者： L.o.osoba A.K.Khan S.o.Adeosun Department of Metallurgical and Materials Engineering University of Lagos Department of Mechanical and Manufacturing Engineering University of Manitoba

This paper presents a study of the standard post-weld heat treatment （PWHT） behaviour of autogenous laser welded γ＇ age-hardenable precipitation strengthened nickel based superalloy Haynes 282 （HY 282）. The study involves a careful and detailed microstructural characterisation as well as an analysis of the weld cracking susceptibility during welding and Gleeble thermo-mechanical physical simulation. Various factors that could influence post-weld cracking in superalloys weld were experimentally examined. our microstructural exami- nation of the as-solution heat treated （SHTed） material and the thermo-mechanically refined grain material shows that intergranular heat affected zone （HAZ） cracking is observable in only the as-welded SHTed material. There was no indication of post-weld heat treatment cracking in all welded materials. our conclusion, in this study, is that the chemistry of superalloy HY 282 which aids the preclusion/formation of deleterious so- lidification microconstituents during welding as well as its relatively slow aging kinetics enhances its resistance to PWHT cracking.

关键词： Cracking Microstructure Analysis Nickel based Superalloy

Results from a comprehensive GPS Network: natural gas pipeline GPS Network

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International Journal of Digital Earth 2013年第S02期6卷 67-80页

作者： o.Yildirim Faculty of Engineering and Natural Sciences Gaziosmanpas¸a UniversityTokatTurkey

Developing the Nabucco engineering infrastructure was the most challenging task imaginable and required state-of-the-art *** this purpose,a NabuccoGlobal Positioning System(GPS)Network was *** is 762 km ***-hundred and two ground control unit points were *** order to provide the relationship with ITRF96 datum,it was surrounded by TFNGN(Turkish Fundamental National GPS Network)and TNVCN(Turkish National Vertical Control Network)*** observations were evaluated in the form of a unique *** being reduced to projection segments,coordinates in ED50 datum were provided between datums by 2D-Helmert *** heights related to the GPS Network were obtained by the improvement of TG-03 data based on a GPS/leveling *** objective of the study is to present the results of a comprehensive engineering project which involved many geodetic considerations including GPS,orthometric heights,and geoid undulations and gives insight into the accuracy and precision of such large projects in terms of recent geodetic *** this study,a Global Navigation Satellite System(GNSS)-based geodetic infrastructure is presented,methods to obtain the necessary precision requirements are provided,and experience is shared in order to provide an example of a large-scale pipeline project,and to provide insight into the planning necessary for future similar engineering projects.

关键词： ITRF96 ED50 datum GPS/leveling accuracy

operations on 3-Dimensional Small Covers

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Chinese Annals of Mathematics,Series B 2010年第3期31卷 393-410页

作者： Shintaro KURoKI Department of Mathematical Science KAIST 335 Gwahangno (373-1 Guseong-dong) Yuseong-gu Daejeon 305-701 Korea School of Mathematical Sciences Fudan University

The purpose of this paper is to study relations among equivariant operations on 3-dimensional small covers. The author gets three formulas for these operations. As an application, the Nishimura＇s theorem on the construction of oriented 3-dimensional small covers and the Lu-Yu＇s theorem on the construction of all 3-dimensional small covers are improved. Moreover, for a construction of 3-dimensional 2-torus manifolds, it is shown that all operations can be obtained by using the equivariant surgeries.

关键词： Equivariant surgery Finite group action Small cover 3-dimensional manifold 3-dimensional simple polytope

Male obesity and subfertility, is it really about increased adiposity？

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Asian Journal of Andrology 2015年第3期17卷 450-458页

作者： Nicole o McPherson Discipline of obstetrics and Gynaecology School of Paediatrics and Reproductive Health The Robinson Institute The University of Adelaide South Australia 5005 Australia Freemasons Foundation Center for Mens Health The University of Adelaide South Australia 5005 Monash IVF Group Melbourne Victoria 3168 Australia

The prevalence of overweight and obesity in reproductive-aged men is increasing worldwide, with 〉70% of men 〉18 years classified as overweight or obese in some western nations. Male obesity is associated with male subfertility, impairing sex hormones, reducing sperm counts, increasing oxidative sperm DNA damage and changing the epigenetic status of sperm. These changes to sperm function as a result of obesity, are further associated with impaired embryo development, reduced live birth rates and increased miscarriage rates in humans. Animal models have suggested that these adverse reproductive effects can be transmitted to the offspring; suggesting that men＇s health at conception may affect the health of their children, in addition to higher adiposity, male obesity is associated with comorbidities, including metabolic syndrome, hypercholesterolemia, hyperleptinemia and a pro-inflammatory state, all which have independently been linked with male subfertility. Taken together, these findings suggest that the effects of male obesity on fertility are likely multifactorial, with associated comorbidities also influencing sperm, pregnancy and subsequent child health.

关键词： embryo fertility infertility inflammation metabolic syndrome sperm