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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

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

The landslide problem

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Journal of Palaeogeography 2015年第2期4卷 109-166页

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

The synonymous use of the general term ＂landslide＂, with a built-in reference to a sliding motion, for all varieties of mass-transport deposits （MTD）, which include slides, slumps, debrites, topples, creeps, debris avalanches etc. in subaerial, sublacustrine, sub- marine, and extraterrestrial environments has created a multitude of conceptual and nomen- clatural problems. In addition, concepts of triggers and Iong-runout mechanisms of mass movements are loosely applied without rigor. These problems have enormous implications for studies in process sedimentology, sequence stratigraphy, palaeogeography, petroleum geol- ogy, and engineering geology. Therefore, the objective of this critical review is to identify key problems and to provide conceptual clarity and possible solutions. Specific issues are the fol- lowing：（1） According to ＂limit equilibrium analyses＂ in soil mechanics, sediment failure with a sliding motion is initiated over a shear surface when the factor of safety for slope stability （F） is less than 1. However, the term landslide is not meaningful for debris flows with a flowing mo- tion. （2） Sliding motion can be measured in oriented core and outcrop, but such measurement is not practical on seismic profiles or radar images. （3） Although 79 MTD types exist in the geological and engineering literature, only slides, slumps, and debrites are viable depositional facies for interpreting ancient stratigraphic records. （4） The use of the term landslide for high- velocity debris avalanches is inappropriate because velocities of mass-transport processes cannot be determined in the rock record. （5） Of the 21 potential triggering mechanisms of sediment failures, frequent short-term events that last for only a few minutes to several hours or days （e.g., earthquakes, meteorite impacts, tsunamis, tropical cyclones, etc.） are more relevant in controlling deposition of deep-water sands than sporadic long-term events that last for thousands to millions of years （e.g.,

关键词： debris flows landslides mass-transport deposits (MTD) slides slumps soilstrength triggering mechanisms reservoir characterization

Recent results on hadron spectroscopy from BES

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Chinese Physics C 2010年第6期34卷 638-643页

作者： Klaus gtzen gSI Helmholtzzentrum für Schwerionenforschung gmbH

The BES-Ⅲ Detector is a very versatile multipurpose device located at the Institute of High Energy Physics （IHEP） in Beijing, China. Concerning the physics program it ties stringently up to the past BES and BES-Ⅱ experiments. Since start of the data taking in the middle of 2008 the accumulated dataset of 200.10^6 J/ψ events and 100.10^6 ψ＇ events already exceeds the world data on these resonances. In addition to studies of the charmonium systems the data offers great opportunity for investigations in the light hadron sector. In detail it will be reported about the confirmation of the enhancement in pp invariant mass in radiative J/ψ decays, the search for decays Y（2175） → K＊0K＊0, observation of a charged K^± in K^±π^0 and observation of a new excited baryon N＊（2065） decaying to pπ^0 and charged onjugate. The first result is based on data taken by BES-Ⅱ and BES-Ⅲ, the latter three on data collected by BES-Ⅱ only.

关键词： light hadrons BES X(1860) Y(2175) k^+ N*(2065)

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

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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

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

Retzius-sparing robotic radical prostatectomy

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Asian Journal of Andrology 2020年第2期22卷 149-151页

作者： Christopher g Eden Department of Urology The Royal Surrey County HospitalGuildford GU27XXUK

Traditional approach to the prostate during radical prostatectomy(RP)when performed by open,laparoscopic,or robotic means has been from its anterior aspect first and has involved suture ligation and division of the dorsal vein complex(DVC),division of the puboprostatic ligaments,and incision of the endopelvic fascia on either side of the *** steps are necessary to liberate the prostate from its surrounding attachments,even though concern has always existed about the likely association between disruption of these structures and postprostatectomy incontinence(PPI).Although perineal prostatectomy leaves these structures intact,it has failed to become widely accepted because of the small incidence of postoperative fecal incontinence and the difficulty in performing a pelvic lymphadenectomy(PLND)when this is indicated.

关键词： robotic radical steps

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

Fluidity and Temperature Profile of Ductile Iron in Thin Sections

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Journal of Iron and Steel Research International 2012年第8期19卷 52-59页

作者： Marcin górny Department of Cast Alloys and Composites Engineering AGH University of Science and Technology

It has been shown that it is possible to produce thin wall ductile iron (TWDI) castings of considerable length using an Archimedes spirals with a wall of 1, 2 or 3 mm in thickness. The fluidities for different moulding materials [(classical mould, chemically bonded silica sand and chemically bonded low-density alumina-silicate ceramic sand (LDASC)], chemical composition, and pouring temperature were estimated. There is a significant temperature drop in thin sections (contrary to typical sections) during the mould filling. A profile of real temperature drop is presented along with theoretical predictions. The high temperature drop of liquid iron results in an increased cooling rate (before the eutectic equilibrium solidification temperature), which in turn affects the solidification and microstructure of TWDI castings. Microstructures were characterized quantitatively using an image analyser. Structure parameters for different wall thicknesses and moulding materials (graphite nodule count, ferrite and cementite fraction) are plotted, which is versus distance from the entrance to the mould cavity. It has been shown that the thin wall castings have a gradient structure. Moreover, a strong influence of LDASC sand (material with low ability to absorb the heat) on the structure parameters of TWDI castings is presented.

关键词： fluidity ductile iron thin wall casting Archimedes spiral