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Communications in Theoretical Physics 2019年第9期71卷 1127-1138页

作者： b.C.Lütfüoglu A.N.Ikot u.S.Okorie A.T.Ngiangia Department of Physics Faculty of ScienceAkdeniz University07058AntalyaTurkey Department of Physics Faculty of ScienceUniversity of Hradec KraloveRokitanskeho6250003Hradec KraloveCzechia Department of Physics Theoretical Physics GroupUniversity of Port HarcourtChobaPort HarcourtNigeria Department of Physics Akwa Ibom State UniversityIkot AkpadenP.M.B.1167UyoNigeria

In this article, we investigate the bound state solution of the Klein Gordon equation under mixed vector and scalar coupling of an energy-dependent deformed Hulthén potential in D dimensions. We obtain a transcendental equation after we impose the boundary conditions. We calculate energy spectra in four different limits and in arbitrary dimension via the Newton-Raphson method. Then, we use a statistical method, namely canonical partition function, and discuss the thermodynamic properties of the system in a comprehensive way. We find out that some of the thermodynamic properties overlap with each other, some of them do not.

关键词： Klein-Gordon equation energy-dependent deformed Hulthén potential energy bound state solution thermodynamic properties

Three-dimensional structured on-chip stacked zone plates for nanoscale X-ray imaging with high efficiency

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Nano Research 2014年第4期7卷 528-535页

作者： Stephan Werner Stefan Rehbein Peter Guttmann Gerd schneider Helmholtz-Zentrum berlin fur Materialien und Energie GmbH Institute for Soft Matter and Functional Materials Albert-Einstein-Straβe15 12489 Berlin Germany

Fresnel zone plates are the key optical elements for nanoscale focusing of X-ray beams with high spatial resolution. Conventional zone plates manufactured by planar nanotechnology processes are limited by the achievable aspect ratios of their zone structures. Additionally, ultra-high resolution X-ray optics with high efficiency requires three-dimensional （3-D） shaped tilted zones. The combination of high spatial resolution and high diffraction efficiency is a fundamental problem in X-ray optics. based on electrodynamical simulations, we find that the optimized zone plate profile for volume diffraction is given by zone structures with radially increasing tilt angles and decreasing zone heights. On-chip stacking permits the realization of such advanced 3-D profiles without significant loss of the maximum theoretical efficiency. We developed triple layer on-chip stacked zone plates with an overlay accuracy of sub-2 nm which fulfills the nanofabrication requirements. Efficiency measurements of on-chip stacked zone plates show significantly increased values compared to conventional zone plates.

关键词： X-ray optics Fresnel zone plates X-ray imaging X-ray microscopy volume diffraction

Photoproduction of multi-meson final states–recent results from the Crystal-barrel/TAPS experiment at ELSA-

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Chinese Physics C 2009年第12期33卷 1105-1112页

作者： u. Thoma HISKP Universitt Bonn Nussallee 14-16 53115 Bonn Germany

Multi-meson final states such as γp →pπ0π0 and γp →pπ0η have been investigated with the Crystal-barrel/TAPS experiment at ELSA. baryon cascades via △π and △η and also via higher mass baryon resonances are clearly observed. based on this data and on data from other reactions a partial wave analysis has been performed from which partial decay widths of various N＊ and △＊ states into the different pπ0π0 and pπ0η decay channels have been determined, leading partly to unexpected results. In addition, polarisation observables have been investigated. The beam asymmetry X has been determined for both reactions and double polarisation data using a longitudinally polarised target and a circularly or linearly polarised photon beam has been taken. Given the angular coverage of the Crystal-baxrel/TAPS experiment this data covers almost the full angular range and phase space. This data will provide new and important information for the partial wave analyses and bring us one step closer towards a complete experiment.

关键词： baryon spectroscopy photoproduction multi-meson final states polarisation observables

Instanton effects on the heavy-quark static potential

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Chinese Physics C 2017年第8期41卷 19-30页

作者： u.T.Yakhshiev Hyun-Chul Kim b.Turimov M.M.Musakhanov Emiko Hiyama Department of Physics Inha UniversityIncheon 22212Republic of Korea RIKEN Nishina Center RIKEN2-1 Hirosawa351-0115 SaitamaJapan School of Physics Korea Institute for Advanced Study(KIAS)Seoul 02455Republic of Korea Theoretical Physics Department National University of UzbekistanTashkent-174Uzbekistan

We investigate instanton effects on the heavy-quark potential, including its spin-dependent part, based on the instanton liquid model. Starting with the central potential derived from the instanton vacuum, we obtain the spin-dependent part of the heavy-quark potential. We discuss the results of the heavy-quark potential from the instanton vacuum. Finally, we solve the nonrelativistic two-body problem, associated with the heavy-quark potential from the instanton vacuum. The instanton effects on the quarkonia spectra are marginal but are required for quantitative description of the spectra.

关键词： instanton-induced interactions heavy-quark potential quarkonia

Numerical investigations of arc behaviour in gas metal arc welding using ANSYS CFX

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Frontiers of Materials Science 2011年第2期5卷 98-108页

作者： M. SCHNICK u. FuESSEL M. HERTEL A. SPILLE-KOHOFF A. b. MuRPHY Institute of Surface and Manufacturing Technology Technische Universitat Dresden Dresden Germany CFX berlin Software GmbH Berlin Germany CSIRO Materials Science and Engineering Lindfield NSW 2070 Australia

Current numerical models of gas metal arc welding（GMAW）are trying to combine magnetohydrodynamics （MRD） models of the arc and voiume of fluid （VoF） models of metal transfer They neglect vaporization and assume an argon atmosphere for the arc region, as it is common practice for models of gas tungsten arc welding, These models predict temperatures above 20 000K anda temperature distribution similar to tungsten inert gas （TIG） arcs： However. current spectroscopic temperature measuretemperatures. In contrast to TIG arcs temperature distrbution. The paper vapour and which is in a yery good res, Futhermore; the model is abile to predict the local central minimum in the radial temperature and the radial electric current density distributions for the first time. The axially symmetric model of the welding torch, the work piece, the wire and the arc （fluid domain） implements MHD as well as turbulent mixing and thermal demixing of metal vapour in argon. The mass fraction of iron vapour obtained from the simulation shows an accumulation in the arc core and another accumulation on the fringes of the arc at 2000 to 5000 K. The demixing effects lead to very low concentrations of iron between these two regions. Sensitive analyses demonstrate the influence of the transport and radiation properties of metal vapour, and the evaporation rate relative to the wire feed. Finally the model predictions are compared with the measuring results of Zielihska et al.

关键词： arc welding numericai simulation GMAW, ANSYS CFX

ADVANCED NICKEL-bASED AND NICKEL-IRON-bASED SuPERALLOYS FOR CIVIL ENGINEERING APPLICATIONS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 453-462页

作者： u. brill ThyssenKrupp VDM GmbH 58791 Werdohl Germany

The use of high-temperature materials is especially important in power station construction, heating systems engineering, furnace industry, chemical and petrochemical industry, waste incineration plants, coal gasification plants and for flying gas turbines in civil and military aircrafts and helicopters. Particularly in recent years, the development of new processes and the drive to improve the economics of existing processes have increased the requirements significantly so that it is necessary to change from well-proven materials to new alloys. Hitherto, heat resistant ferritic steels sufficed in conventional power station constructions for temperatures up to 550℃ newly developed ferritic/martensitic steels provide sufficient strength up to about 600 - 620℃. In new processes, e.g. fluidized-bed combustion of coal, process temperatures up to 900℃ occur. However, this is not the upper limit, since in combustion engines, e.g. gas turbines. Material temperatures up to 1100℃ are reached locally. Similar development trends can also be identified in the petrochemical industry and in the heat treatment and furnace engineering. The advance to ever higher material temperatures now not only has the consequence of having to use materials with enhanced high-strength properties, considerable attention now also has to be given to their chemical stability in corrosive media. Therefore not only examples of the use of high-temperature alloys for practical applications will be given but also be contributed to some general rules for material selection with regard to their high-temperature strength and corrosion resistance.

关键词： nickel-based alloy high-temperature strength high-temperature corrosion resistance civil engineering application

bone cement adhesion on ceramic surfaces—Surface activation of retention surfaces of knee endoprostheses by atmospheric pressure plasma *** surface treatment

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Journal of Advanced Ceramics 2016年第2期5卷 137-144页

作者： b.MARX C.MARX R.MARX u.REISGEN D.C.WIRTZ ISF Welding and Joining Institute RWTH Aachen university Pontstrasse 49 52062 Aachen GermanyCC&A Medical Components Ltd. Center for Biomedical Engineering Pauwelsstrasse 17 52074 Aachen Germany CC&A Medical Components Ltd. Center for Biomedical Engineering Pauwelsstrasse 17 52074 Aachen Germany ISF Welding and Joining Institute RWTH Aachen university Pontstrasse 49 52062 Aachen Germany Orthopaedics and Traumatology Clinic university Hospital bonn Sigmund-Freud-Strasse 25 53127 Bonn Germany

CoCrMo alloys are contraindicated for allergy sufferers. For these patients, uncemented and cemented prostheses made of titanium alloy are indicated. Knee prostheses machined from that alloy, however, may have poor tribological behavior. Therefore, for allergy sufferers, knee replacements in form of cemented high-strength oxide ceramic prostheses which reveal excellent tribological behavior are suitable. In addition, the rate of particle induced aseptic loosening may be reduced. For adhesion of bone cement, the smooth ceramic surface, however, exposes inefficient mechanical retention spots as compared with a textured metal surface. undercuts generated by corundum blasting, which in the short and intermediate term are highly efficient on a CoCrMo surface, are not appropriate on a ceramic surface due to the brittleness of ceramics. The corresponding textures may initiate cracks which will weaken the strength of a ceramic prosthesis. Due to the lack of textures, mechanical retention is poor or even not existent. Micromotions are facilitated and early aseptic loosening is predictable. Instead silicoating of the ceramic surface will allow specific adhesion and result in better hydrolytic stability of bonding, thereby preventing early aseptic loosening. Silicoating, however, presupposes a clean and chemically active surface which may be achieved by atmospheric plasma or thermal surface treatment. In order to evaluate the effectiveness of silicoating, the bond strengths of atmospheric plasma versus thermal surface treated and silicoated ZPTA (zirconia platelets toughened alumina) surfaces were compared with “as-fired” surfaces by utilizing TiAlV probes (diameter: 6 mm) for traction-adhesive strength test. After preparing samples for traction-adhesive strength test (sequence: ceramic substrate, silicate layer and penetrated silane, protective lacquer (PolyMA), bone cement, TiAlV probe), they were aged up to 150 days at 37°C in Ringer’s solution. The bond strengths observed

关键词： total knee replacement out of oxide ceramics aseptic loosening allergenic potential atmospheric plasma treatment silicoating hydrolytic stability

L_p-DICHOTOMY OF LINEAR DIFFERENTIAL EQuATIONS IN AN ARbITRARY bANACH SPACE

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Chinese Annals of Mathematics,Series b 2003年第4期24卷 485-490页

作者： A.KOSSEVA S.KOSTADINOV K.schneider Department of Mathematics Technical University61Sankt Petersburg blvd4000 PlovdivDepartment of Mathematics and InformaticsUniversity of Plovdiv"P.Hilendarski"24Tzar Assenstr.4000 PlovdivBulgaria.WIAS BerlinMohrenstr.3910117 BerlinDeutschland.

The notion of Lp-dichotomy for linear differential equations with possibly unbounded oper-ator is introduced. by help of banach fixed point theorem sufficient conditions for the existenceof bounded solutions of nonlin... 详细信息

关键词： Ordinary differential equations Dichotomy Existence of bounded solutions

Navier Slip and Heat Transfer in a Nanofluid Due to a Stretching/Shrinking Sheet:An Analytical Study

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1551-1567页

作者： A.b.Vishalakshi u.S.Mahabaleshwar M.EL.Ganaoui R.bennacer Department of Mathematics ShivagangotriDavangere UniversityDavangere577007India Institut universitaire de Technologie de Longwy Universitéde Lorraine 186 rue de LorraineCosnes et Romain54400France LMT/ENS-Cachan/CNRS/universitéParis Saclay Cachan94235France

This paper is devoted to the analysis of the heat transfer and Navier’s slip effects in a non-Newtonian Jeffrey fluid flowing past a stretching/shrinking *** nanoparticles,namely,Cu and Al_(2)O_(3)are used with a water-based fluid with Prandtl number *** slip flow is assumed to occur when the characteristic size of the flow system is small or the flow pressure is very *** using the similarity transformations,the governing nonlinear PDEs are turned into ordinary differential equations(ODE’s).Analytical results are presented and analyzed for various values of physical parameters:Prandtl number,Radiation parameter,stretching/shrinking parameter and mass transpiration for the flow and heat *** considered problem is relevant to various physical applications in the field of engineering,e.g.,the production of certain materials,the preparation of plastic and rubber sheets and glass *** is shown that the considered nanofluid increases the thermal *** nanoparticles act as a heater by increasing the solid volume fraction and thermal *** versa,they can act as a cooler if the strength of magnetic field is *** flow strength decreases by increasing the values of Deborah number.

关键词： Nanofluid navier’s slip radiation ordinary differential equations

Studies on impact sensitivity of nanosized trinitrotoluene (TNT) confined in silica processed by sol-gel method

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Defence Technology（防务技术） 2016年第1期12卷 46-51页

作者： s.v.ingale p.b.wagh p.u.sastry c.b.basak d.bandyopadhyay s.b.phapale satish c.gupta Applied Physics Division Bhabha Atomic Research Centre Mumbai India Solid State Physics Division Bhabha Atomic Research Centre Mumbai India Glass andAdvanced Materials Division Bhabha Atomic Research Centre Mumbai India Heavy Water Division Bhabha Atomic Research Centre Mumbai India Chemistry Division Bhabha Atomic Research Centre Mumbai India

Nano-sized trinitrotoluene(TNT) material restrained in silica gel has been prepared by using the sol-gel process to study the effect of varying porosity in gel on the sensitivity of TNT. The TNT content in the gel has been varied from 60 to 90 wt %(at fixed acetone/tetramethoxysilane ratio of 50). Also, for a fixed TNT content of 75 wt %, the pore structure in the gel has been varied by changing the ratio of silica gel precursor to the solvent. The resultant TNT–silica gel composites have been characterized using scanning electron microscopy, thermal analysis, small angle X-ray scattering and surface area analysis techniques. Impact sensitivity studies were carried out using Fall Hammer Impact Test. The results showed that the sensitivity of nanostructured explosives prepared by sol-gel process can be tailored precisely by controlling the process parameters.

关键词：溶胶-凝胶法三硝基甲苯 TNT 敏感性二氧化硅纳米溶胶-凝胶过程扫描电子显微镜