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Journal of Iron and Steel Research International 2012年第10期19卷 64-73页

作者： g Subhash Chander g Madhusudhan Reddy A Venugopal Rao Swarna Bharathi Institute of Science and Technology Khammam 507002APIndia Defense Metallurgical Research Laboratory Kanchanbagh 500058APIndia

Fundamental investigation of continuous drive friction welding of austenitic stainless steel (AISI 304) and low alloy steel (AISI 4140) is described. The emphasis is made on the influence of rotational speed on the microstructure and mechanical properties such as hardness, tensile strength, notch tensile strength and impact toughness of the dissimilar joints. Hardness profiles across the weld show the interface is harder than the respective parent metals. In general, maximum peak hardness is observed on the stainless steel side, while other peak hardness is on the low alloy steel side. A trough in hardness distribution in between the peaks is located on the low alloy steel side. Peak hardness on the stainless steel and low alloy steel side close to the interface increases with a decrease in rotational speed. All transverse tensile joints fractured on stainless steel side near the interface. Notch tensile strength and impact toughness increase with increase in rotational speed up to 1 500 r/min and decrease thereafter. The mechanism of influence of rotational speed for the observed trends is discussed in the torque, displacement characteristics, heat generation, microstructure, fractography and mechanical properties.

关键词： friction welding dissimilar metal joint austenitic stainless steel low alloy steel microstructure impact toughness tensile strength

Diagnostic approach to patients with cholestatic jaundice

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World Journal of gastroenterology 1999年第3期5卷 252-262页

作者： Assy N Jacob g Spira g Edoute Y Liver Disease Unit and Department of Internal Medicine C Rambam Medical Center Haifa and Department of Anatomy the Bruce Rappaport Faculty of Medicine Technion-Israel Institute of Technology Haifa Israel

Conjugated hyperbilirubinemia due to any form of hepatobiliary disease is essentially the result of impairment in bile formation and/or bile flow, a condition known as cholestasis[1,2].

关键词： AIDS cell US ERCP ggT Diagnostic approach to patients with cholestatic jaundice PBC TPN

Injection molding of micro-porous titanium alloy with space holder technique

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Rare Metals 2011年第6期30卷 565-571页

作者： gülsah Engin Bülent Aydemir H.zkan gülsoy Marmara University Institute Graduate Studies Pure and Applied Sciences TUBITAK National Metrology Institute Marmara University Technical Education FacultyMaterials Department Tubitak-MRC Materials Technologies Research Institute

The powder space holder （PSH） and powder injection molding （PIM） methods have an industrial competitive advantage because they are capable of the net-shape production of micro-sized porous parts. In this study, micro-porous Ti6Al4V alloy （Ti64） parts were produced by the PSH-PIM process. Ti64 alloy powder and spherical polymethylrnethacrylate （PMMA） particles were used as a space holder material. After molding, binder debinding was performed by thermal method under inert gas. Debinded samples were sintered at 1250℃ for 60min in a vacuum （10-4 Pa）. Metallographic studies were conducted to determine densification and the corresponding microstructural changes. The surface of sintered samples was examined by SEM. The compressive stress and elastic modulus of the rificro-porous Ti64 samples were determined. The effects of fraction of PMMA on the properties of sintered micro-porous Ti64 alloy samples were investigated. It was shown that the fraction of PMMA could be controlled to affect the properties of the Ti alloy.

关键词： powder injection molding titanium powder porous metal sintering

Hadron spectroscopy from B-factories

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Chinese Physics C 2010年第9期34卷 1195-1200页

作者： g.Pakhlova Institute for Theoretical and Experimental Physics(Russia)

We review the recent experimental results on hadron spectroscopy from B-factories focusing on the exotic charmonium-like *** them we discuss the X（3872）,Y（3940）,Z（4430）＋,Z（4050）＋,Z（4250）＋ and Y（4140） states found in B-meson decays,the X（3940） and X（4160） states produced in double charmonium production,the Y（4260）,Y（4325）,Y（4660） and X（4630） states produced with initial-state radiation in e ＋ eannihilation and the X（3915）,Y（4350） states observed in two-photon collisions.

关键词： hadron spectroscopy charmonium charmonium-like states charm mesons cross section

glossary:A supplement to “Submarine fans:A critical retrospective(1950-2015)” in the Journal of Palaeogeography (2016,5[2])

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Journal of Palaeogeography 2016年第3期5卷 258-277页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at Arlington

In this gtossary, setected terms and concepts associated with submarine fans are defined.

关键词： Submarine fans Submarine canyons Submarine channeLs Submarine Lobes Abyssal plains

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet g DOUgLAS Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

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Status of KLOE-2

Chinese Physics C 2010年第6期34卷 918-923页

作者： g.Venanzoni Laboratori Nazionali di Frascati dell'INFN

In a few months the KLOE-2 detector is expected to start data taking at the upgraded DAФNE φ-factory of INFN Laboratori Nazionali di Frascati. It aims to collect 25 fb^-1 at the φ（1020） peak, and about 5 fb^-1 in... 详细信息

关键词： electron-positron annihilation φ-factory kaon interferometry discrete symmetries γγ physics scalar spectroscopy hadronic cross sections g-2 αem

Production and characterization of ZnO nanoparticles and porous particles by ultrasonic spray pyrolysis using a zinc nitrate precursor

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 651-656页

作者： Burak Ebin Elif Arτg Burak zkal Sebahattin gürmen Metallurgical & Materials Engineering Department Istanbul Technical University

ZnO nanoparticles and porous particles were produced by an ultrasonic spray pyrolysis method using a zinc nitrate precursor at various temperatures under air atmosphere. The effects of reaction temperature on the size and morphology of ZnO particles were investi- gated. The samples were characterized by energy dispersive spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. ZnO particles were obtained in a hexagonal crystal structure and the crystallite shapes changed from spherical to hex- agonal by elevating the reaction temperature. The crystallite size grew by increasing the temperature, in spite of reducing the residence time in the heated zone. ZnO nanoparticles were obtained at the lowest reaction temperature and ZnO porous particles, formed by aggregation of ZnO nanoparticles due to effective sintering, were prepared at higher temperatures. The results showed that the properties of ZnO particles can be controlled by changing the reaction temperature in the ultrasonic spray pyrolysis method.

关键词： zinc oxide nanoparticles nanocrystallites porous materials ultrasonic applications spray pyrolysis

An approach for optimization of the wall thickness (weight) of a thick-walled cylinder under axially non-uniform internal service pressure distribution

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Defence Technology（防务技术） 2017年第3期13卷 150-157页

作者： Onur güngor MKE Kurumu Mühimmat Fabrikas Ar-ge Müdürlügü 71100 Merkez

Today, improving the weight/load carrying capacity ratio of a part is the matter of studies in most of the scientific and industrial *** dimensions, the amount of material removed from outer and inner radius while manufacturing and the service pressure applied affect the residual stress distribution throughout the wall thickness and hence the load-bearing capacity of a thick-walled cylinder. Calculation of residual stresses after autofrettage process and optimization of autofrettage outline dimensions by using the amount of service pressures applied are common issues in *** this study, mandrel-cylinder tube interference dimensions were renovated by using traditional methods for swage autofrettage process of a gun barrel. Also, the residual stresses in the cylinder after autofrettage process, inside and outside material removal process and the variable service pressure throughout the cylinder applied were taken into consideration and incorporated into the design. By using the constrained optimization method, wall thickness(thus the weight) was optimized(minimized)to achieve the specified safety factor along the length of the cylinder. For the same cylinder, the results of the suggested analytical/with residual stress calculation approach were compared to analytical/without residual stress calculation results and numerical topology optimization method calculation results. Since the experimental measurement results are not yet available, it was not possible to compare them with the calculation *** suggested approach enabled 22.9% extra weight reduction in proportion to numerical topology optimization and enabled 4.2% extra weight reduction in proportion to analytical/without residual stress *** this approach, the gain from residual stresses after autofrettage operation, the loss of residual stresses after material removal, and the effects of service pressures can be taken into account for each stage of design.

关键词：尺寸优化圆筒壁厚厚壁圆筒载重量残余应力分析非均匀应力计算方法自增强材料

Morphology and distribution of Pronoctiluca (Dinoflagellata, incertae sedis) in the Pacific Ocean

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Acta Oceanologica Sinica 2013年第4期32卷 71-76页

作者： góMEZ Fernando Department of Biological Oceanography Institute of Oceanography University of S o Paulo

The diversity and distribution of Pronoctiluca, a marine dinoflagellate of enigmatic systematic position, was studied in the vicinity of the Kuroshio and Oyashio Currents, the Philippines, Celebes, Sulu and South China Seas, western and central equatorial and southeast Pacific Ocean. The abundance of Pronoctiluca was high- er, with a wide vertical distribution, in eutrophic temperate regions, whereas it was nearly absent in surface waters of oligotrophic tropical regions. Most of the specimens corresponded to P. spinifera. Pronoctiluca pelagica, covered by hyaline layers and with no flagella, is considered as an encysted form. The bipartition was only observed in P. acuta-P, spinifera forms, that together with the occurrence of intermediate forms between P. spinifera and P. pelagica suggest that they may correspond to developmental stages of a single species. Pronoctiluca is essential to understanding the evolutionary history of the alveolates.

关键词： Alveolata basal dinoflagellates Dinophyceae heterotrophic flagellate Noctilucales plankton