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Simulation of.the f.ssion dynamics of.the excited compound nuclei ^206Po and ^168Yb produced in the reactions ^12C＋^194Pt and ^18O＋^150Sm

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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

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

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..

ON MULTIPLICATION AND COMULTIPLICATION MODULES

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Acta Mathematica Scientia 2011年第2期31卷 694-700页

作者： h. Ansari-Toroghy f. f.rshadif.r Department of.Mathematics Faculty of Science University of Guilan

This article deals with some results concerning multiplication and comultipli- cation modules over a commutative ring.

关键词： Multiplication modules comultiplication modules cocyclic modules

The Zariski Topology on the Second Spectrum of.a Module

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Algebra Colloquium 2014年第4期21卷 671-688页

作者： h. Ansari-Toroghy f. f.rshadif.r Department of.Pure Mathematics Faculty of Mathematical Sciences University of Guilan P.O. Box 41335-19141 Rasht Iran

Let R be a commutative ring and M be an R-module. The second spectrum Spec^S（M） of.M is the collection of.all second submodules of.M. We topologize Spec^S（M） with Zariski topology, which is analogous to that f.r Spec（R）, and investigate this topolog- ical space. f.r various types of.modules M, we obtain conditions under which Spec^S（M） is a spectral space. We also investigate Specs （M） with quasi-Zariski topology.

关键词： second submodule second spectrum cotop module spectral space Zariskitopology

Mechano-thermal synthesis and characterization of.nano-structured f./f.S f.r application in photocatalysis

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Particuology 2018年第2期16卷 72-80页

作者： h. Esmaili S. Sheibani f. Rashchi School of.Metallurgy and Materials Engineering College of Engineering University of Tehran Tehran 11155-4563 Iran

A novel method was used to prepare a nano-structured 32 wt% f./f.S core/shell powder via a mechanothermal route by l-h heat treatment of.a mechanically activated powder mixture of.f. and S. The structural and microstructural characteristics, f.rmation mechanism, magnetic properties, and photocatalytic activity of.the powder were studied by X-ray dif.raction, f.eld emission scanning electron microscopy, transmission electron microscopy, surf.ce area analysis, dif.erential scanning calorimetry, vibrating sample magnetometry, and UV-vis spectrophotometry. A detailed study of.the mechanism of.transf.rmation showed that during the heat treatment process, an f.S2 phase was f.rmed as the intermediate product. In the f.nal product, an f.S shell approximately 2 nm in thickness was f.rmed on the f. core. In the presence of.NaCI as a process control agent, the particle size decreased and the size distribution became more unif.rm. Mechanical activation and NaCI addition together led to a decrease of.the saturation magnetization f.om 82 to 74emu/g. The photocatalytic activity of.the powder in the degradation of.methylene blue was 50%.

关键词： f./f.S Core-shell Mechano-therma Nano-structure Photocatalyst

ANOMALOUS Ef.ECT Of.PRESSURE ON ThE CURIE TEMPERATURE IN MEChANICALLY ALLOYED f.-Ni INVAR

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 205-209页

作者： X.h. Wei f. Ono Department of.Electronic Science Huizhou University Huizhou 516007 China Department of.Physics Okayama University 3-1-1 Tsushima-Naka Okayama 700-8530 Japan

Measurements of.magnetic susceptibility in mechanically alloyed f.-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of.decrease in the Curie temperature f.r 700℃ annealed specimen was larger than that annealed at 1000℃. This result can be explained by considering the f.ct that the width of.the concentration f.uctuation becomes larger in the specimen annealed at lower temperature.

关键词： invar alloy f.-Ni, mechanical alloying Curie temperature

Ab-Initio Study of.Cobalt Impurity Ef.ects on Phonon Spectra, Mechanical and Thermal Properties of.Single Wall Carbon Nanotube （5,0）

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Chinese Physics Letters 2014年第4期31卷 110-113页

作者： h. Tashakori B. Khoshnevisan f. Kanjouri f.culty of.Physics University of Kashan Kashan Iran f.culty of.Physics Kharazmi University Karaj Iran

We use density f.nctional perturbation theory based on the pseudo-potential to calculate the phonon spectrum, phonon density of.states, specif.c heat capacity and mechanical properties of.pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In the calculations, we consider one Co atom in the center of.the unit cell of.the tube and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tube becomes magnetic. Young＇s modulus f.r both systems is about 1 TPa （＇af.er Co-doping it goes slightly higher） and the Poisson ratio f.r the pristine tube becomes quite a bit larger than the doped one. On the other hand, the calculated value of.radial breath mode f.r the pristine CNT is in good agreement with the experimental reports while af.er Co-doping it is increased. In addition, heat capacity of.the doped CNT is reduced, which leads to some important empirical applications.

关键词： Wall Carbon Nanotube Ab-Initio pseudo-potential

f.ll-band error control and crack-f.ee surf.ce f.brication techniques f.r ultra-precision f.y cutting of.large-aperture KDP crystals

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f.ontiers of.Mechanical Engineering 2017年第2期12卷 193-202页

作者： f. h. ZhANG S. f. WANG C. h. AN J. WANG Q. XU Department of.Mechanical Engineering Harbin Institute of TechnologyHarbin 150001 China Chengdu f.ne Optical Engineering Research Center Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） crystals are widely used in the laser path of.inertial conf.nement f.sion （ICf. systems. The most common method of.manuf.cturing half.meter KDP crystals is ultra-precision f.y cutting. When processing KDP crystals by ultra-precision f.y cutting, the dynamic characteristics of.the f.y cutting machine and f.uctuations in the f.y cutting environment are translated into surf.ce errors at dif.erent spatial f.equency bands. These machin- ing errors should be suppressed ef.ectively to guarantee that KDP crystals meet the f.ll-band machining accuracy specif.ed in the evaluation index. In this study, the anisotropic machinability of.KDP crystals and the causes of.typical surf.ce errors in ultra-precision f.y cutting of.the material are investigated. The structures of.the f.y cutting machine and existing processing parameters are optimized to improve the machined surf.ce quality. The f.ndings are theoretically and practically important in the development of.high-energy laser systems in China.

关键词： ultra-precision f.y cutting large-aperture KDP crystals spatial f.equency processing error