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Chinese Physics C 2017年第4期41卷 69-74页

作者： H. Eslamizadeh f. Bagheri Department of.Physics Persian Gulf University *** Bushehr Iran

A two-dimensional dynamical model based on the Langevin equation was used to study the f.ssion dynamics of.the compound nuclei ^206Po and ^168Yb produced in the reactions ^12C＋^194Pt and ^18O＋^150Sm,*** f.ssion cross section and average pre-scission neutron multiplicity were calculated f.r the compound nuclei ^206Po and ^168Yb,and results of.the calculations compared with the experimental *** elongation coordinate was used as the f.rst dimension and the projection of.the total spin of.the compound nucleus onto the symmetry axis,K,considered as the second dimension in the Langevin dynamical *** the two-dimensional calculations,a constant dissipation coef.icient of.K and a non-constant dissipation coef.icient have been used to reproduce the abovementioned experimental *** is shown that the two-dimensional Langevin equation can satisf.ctorily reproduce the f.ssion cross section and average pre-scission neutron multiplicity f.r the compound nuclei ^206Po and ^168Yb by using constant values of.the dissipation coef.icient of.K equal to γκ=0.18（MeV zs）^-1/2 and γκ= 0.20（MeV zs）^-1/2f.r the compound nuclei ^206Po and ^168Yb,respectively.

关键词： dissipation coef.icient Langevin model f.ssion cross section

Study of.the Reaction of.5-Aryl-7-hydrazino-2-phenylpyra- zolo[1,5-c]pyrimidines with 1,3-Dicarbonyl Compounds

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Chinese Journal of.Chemistry 2011年第11期29卷 2451-2460页

作者： Atta, Kamal f. M. Chemistry Department Faculty of Science Alexandria University lbrahimia P. O. Box 426 Alexandria 21321 Egypt

A novel synthetic method f.r the preparation of.5-aryl-7-（3,5-dimethyl-lH-pyrazol-l-yl）-2-phenylpyra- zolo[1,5-c]-pyrimidines and 1-（5-aryl-2-phenylpyrazolo[1,5-c]pyrimidin-7-yl）-3-methyl-lH-pyrazol-5-ols is provided by condensative cyclization of.5-aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines with 1,3-dicarbonyl compounds. The study of.the more reactive position f.r electrophilic substitusion reactions on such ring system was also achieved.

关键词： cyclization electrophilic substitution pyrazolylpyrazolopyrimidine IR NMR mass spectrometry

Can Heavier Liquid f.oat on Top of.a Lighter One？

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Chinese Physics Letters 2011年第1期28卷 127-129页

作者： A. H. Ayyad f. Takrori Department of.Chemistry Faculty of Science and Technology Hebron University P.O. Box 40 Hebron West Bank Palestine

We report on a f.rst observation of.a f.oating- spherical Hg （density 13g/cm3） drop on top of.a glycerin （density 1.26g/cm3） drop, the latter is hemispherical and about f.ur times larger in volume. This observation is clearly against nature＇s gravity law and has never been reported bef.re. Here we present spectacular high resolution photos that clearly demonstrate this remarkable f.oating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of.tap water displays the same phenomenon. Increasing the volume of.the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is f.und enough to show the same f.oating phenomenon. This f.oating mercury as a phenomenon is puzzling. On this length scale it seems that surf.ce tension and curvature dominate over gravity.

关键词： Sof. matter liquids and polymers f.uid dynamics Surf.ces interf.ces and thin f.lms

IMPROVEMENT Of.TYPE IV CRACKING RESISTANCE Of.9Cr HEAT RESISTING STEEL WELDMENT BY BORON ADDITION

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 331-337页

作者： M.Tabuchi M.Kondo T.wa.a.abe H.Hongo f.Yin f.abe National Institute f.r Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 Japan

Creep lives of.high Cr f.rritic heat resisting steel weldments decrease due to Type Ⅳ f.acture, which occurs as a result of.f.rmation and growth of.creep voids and cracks on grain boundaries in f.ne-grained heat af.ected zone (HAZ). Because boron is considered to suppress the coarsening of.grain boundary precipitates and growth of.creep voids, we have investigated the ef.ect of.boron addition on the creep properties of.9Cr steel weldments. f.ur kinds of.9Cr3WSCoVNb steels with boron content varying f.om 4.7×10-5 to 1.8×10-4 and with nitrogen as low as 2.0×10-5 were prepared. The steel plates were welded by gas tungsten arc welding and crept at 923K. It was f.und that the microstructures of.HAZ were quite dif.erent f.om those of.conventional high Cr steels such as P91 and P92, namely the f.ne-grained HAZ did not exist in the present steel weldments. Boron addition also has the ef.ect to suppress coarsening of.grain boundary carbides in HAZ during creep. As a result of.these phenomena, the welded joints of.present steels showed no Type Ⅳ f.actures and much better creep lives than those of.conventional steels.

关键词： high Cr heat resistant steel welded joint boron addition Type IV f.acture

Improving Solution of.Euler Equations by a Gas-Kinetic BGK Method

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西北工业大学学报 2009年第1期27卷 1-5页

作者： Liu, Ya Gao, Chao Liu, f. National Key Laboratory of.Aerodynamic Design and Research Northwestern Polytechnical University Xi'an 710072 China Department of.Mechanical and Aerospace Engineering University of California Irvine CA 92697-3975 United States

*** well known JST(Jameson-Schmidt-Turkel) scheme requires the use of.a dissipation *** propose using gas-kinetic BGK(Bhatnagar-Gross-Krook) method,which is based on the more f.ndamental Boltzmann equation,in order to obviate the use of.dissipation term and obtain,we believe,an improved *** 1 deals essentially with three things:(1) as analytical solution of.molecular probability density f.nction at the cell interf.ce has been obtained by the Boltzmann equation with BGK model,we can compute the f.ux term by integrating the density f.nction in the phase space;eqs.(8) and(11) require caref.l attention;(2) the integrations can be expressed as the moments of.Maxwellian distribution with dif.erent limits according to the analytical solution;eqs.(9) and(10) require caref.l attention;(3) the discrete equation by f.nite volume method can be solved using the time marching *** are perf.rmed by the BGK method f.r the Sod′s shock tube problem and a two-dimensional shock ref.ection *** results are compared with those of.the conventional JST scheme in f.gs.1 and *** BGK method provides better resolution of.shock waves and other f.atures of.the f.ow f.elds.

关键词： Euler equations Boltzmann equation gas-kinetic BGK(Bhatnagar-Gross-Krook) scheme JST(Jameson-Schmidt-Turkel) scheme shock tube shock ref.ection

Bound states of.the Dirac equation with position-dependent mass f.r the Eckart potential

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Chinese Physics B 2013年第1期22卷 62-67页

作者： Bahar M. K. Yasuk f. Department of.Physics Erciyes University Department of.Physics Karamanoglu Mehmetbey University

Studying with the asymptotic iteration method, we present approximate solutions of.the Dirac equation f.r the Eckart potential in the case of.position-dependent mass. The centrif.gal term is approximated by an exponen... 详细信息

关键词： Dirac equation position-dependent mass Eckart potential asymptotic iteration method

A building-based data capture and data mining technique f.r air quality assessment

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f.ontiers of.Environmental Science & Engineering 2011年第4期5卷 543-551页

作者： Ni SHENG U wa TANG f.culty of.Management and Administration Macao University of Science and TechnologyMacaoChina Department of.Civil and Environmental Engineering University of MacaoMacaoChina Dirccao dos Servicos de Proteccao Ambiental MacaoChina

Recently,a building-based air quality model system which can predict air quality in f.ont of.individual buildings along both sides of.a road has been *** the Macao Peninsula as a case study,this paper shows the advantages of.building-based model system in data capture and data *** with the traditional grid-based model systems with input/output spatial resolutions of.1-2 km,the building-based approach can extract the street conf.guration and traf.ic data building by building and theref.re,can capture the complex spatial variation of.traf.ic emission,urban geometry,and air *** non-homogeneous distribution of.air pollution in the Macao Peninsula was modeled in a highspatial resolution of.319 receptors·km^(-2).The spatial relationship among air quality,traf.ic f.ow,and urban geometry in the historic urban area is *** study shows that the building-based approach may open an innovative methodology in data mining of.urban spatial data f.r environmental *** results are particularly usef.l to urban planners when they need to consider the inf.uences of.urban f.rm on street environment.

关键词： traf.ic air pollution spatial distribution high resolution geographic inf.rmation system

A comparative study of.semi-active control strategies f.r base isolated buildings

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Earthquake Engineering and Engineering Vibration 2015年第3期14卷 487-502页

作者： Oliveira f. Morais P. Suleman A. National Laboratory f.r Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Scholarship HolderPh D CandidateMSc National Laboratory f.r Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Researcher Ph D University of.Victoria Dep. Mechanical Engineering PO Box 1700 Stn CSC Victoria BC V8W 2Y2 Canada Professor Ph D PEng

A comparative analytical study of.several control strategies f.r semi-active(SA) devices installed in baseisolated buildings aiming to reduce earthquake induced vibrations is *** f.rce tracking schemes comprising a linear controller plus a 'clipped' algorithm and a nonlinear output f.edback controller(NOf.) are considered to tackle this *** controllers include the integral controller(I),the linear quadratic regulator(LQR) and the model predictive controller(MPC).A single degree-of.f.eedom system subjected to input accelerograms representative of.the Portuguese seismic actions are f.rst used to validate and evaluate the f.asibility of.these *** obtained results show that structural systems using SA devices can in general outperf.rm those equipped with passive devices f.r lower f.ndamental f.equency structural systems,namely base-isolated *** ef.ectiveness of.the proposed strategies is also evaluated on a 10 storey base-isolated dual f.ame-wall *** f.rce tracking scheme with an integral controller outperf.rms the other three as well as the original structure and the structure equipped with passive devices.

关键词： semi-active control integral controller linear qua

Combined Ef.ect of.Magnetic f.eld and Thermal Dispersion on a Non-Darcy Mixed Convection

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Journal of.Thermal Science 2011年第3期20卷 276-282页

作者： M. f. EI-Amin Shuyu Sun Computational Transport Phenomena Laboratory （CTPL） Division of Physical Sciences and Engineering （PSE）King Abdullah University of Science and Technology （KAUST） Thuwal 23955-6900 Jeddah Kingdom of Saudi Ara-bia Mathematics Department Faculty of Science South Valley University Aswan 81528 EGYPT

This paper is devoted to investigate the inf.uences of.thermal dispersion and magnetic f.eld on a hot semi-inf.nite vertical porous plate embedded in a saturated Darcy-f.rchheimer-Brinkman porous medium. The coef.icient of.thermal dif.usivity has been assumed to be the sum of.the molecular dif.usivity and the dynamic dif.usivity due to mechanical dispersion. The ef.ects of.transverse magnetic f.eld parameter (Hartmann number Ha), Reynolds number Re (dif.erent velocities), Prandtl number Pr (dif.erent types of.f.uids) and dispersion parameter on the wall shear stress and the heat transf.r rate are discussed.

关键词： Thermal dispersion non-Darcy convection magneto-hydro-dynamics porous media geothermal systems

AITEB - An European Research Project on Aero-thermodynamics of.Turbine Endwalls and Blades

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Journal of.Thermal Science 2004年第2期13卷 97-108页

作者： f. HASELBACH H.-P. SCHIf.ER Rolls-Royce Deutschland Turbines Eschenweg 11 15827 Dahlewitz GermanyRolls-Royce Deutschland Turbines Eschenweg 11 15827 Dahlewitz Germany

The paper delivers an overview on the European research project AITEB - Aerothermal Investigations on Turbine Endwalls and Blades, which started in year 2000 in the course of.the 5. f.amework Programme (GROWTH). The aim is to submit an integrated technology and design tool package f.r the advanced, aerothermal highly loaded design of.turbines, especially: Experimental/numerical investigation on heat transf.r and f.lm-cooling in separated f.ow f.r highly loaded blades including advanced trailing edge cooling Heat transf.r/ improved cooling of.turbine endwalls: Experimental/numerical work on cooling of.turbine endwalls, shrouds and recessed blade tips. Optimised Cf.-process (drawing-grid-modelling-postprocessing-risk assessment) in order to derive the 'best practice' to use Cf. as a time ef.ective tool. Af.er most of.the project lif., an overview on the project is delivered. Experimental results of.test series at various test sites are compared to numerical simulations of.the industrial and university partners.

关键词： turbines aerothermal endwalls blades cooling-technology experiment Cf..