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Ξ^-t quasibound state instead of ΛΛnn bound state

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Chinese Physics C 2020年第2期44卷 94-100页

作者： h.Garcilazo A.Valcarce j.Vijande Escuela Superior de Física y Matemáticas Instituto Politécnico NacionalEdificio 907738 México D.F.Mexico Departamento de Física Fundamental Universidad de Salamanca37008 SalamancaSpain Departamento de Física Atómica Molecular y NuclearUniversidad de Valencia(UV)and IFIC(UV-CSIC)46100 ValenciaSpain IRIMED joint Research Unit(IIS La Fe-UV) 46100 ValenciaSpain

The coupledΛΛnn-Ξ-pnn system was studied to investigate whether the inclusion of channel coupling is able to bind theΛΛnn *** use a separable potential three-body model of the coupledΛΛnn-Ξ-pnn system and a variational four-body calculation with realistic *** results exclude the possibility of aΛΛnn bound state by a large ***,we found aΞ-t quasibound state above theΛΛnn threshold.

关键词： baryon-baryon interactions few-body systems Faddeev equations

The Performance of EOS Models in the Prediction of Vapor-Liquid Equilibria in Asymmetric Natural Gas Mixtures

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Chinese journal of Chemical Engineering 1998年第3期6卷 29-37页

作者：王利生 h.Gardeler j.Gmehling Department of Technical Chemisity University of OldenburgP.O.Box 2503D-26111 OldenburgGermany

The aim of this work is to apply cubic equations of state(EOS)to vapor-liquid equilibriacalculations of gas-heavy hydrocarbon systems,which are asymmetric in molecular size and areusually found in natural *** has been done to test the validity of the original PSRKand the cubic simplified perturbed hard-chain(CSPhC)models for global phase *** results show that both equations overpredict vapor pressure in the near critical *** the prediction of the solubilities of high molecular weight(MW)hydrocarbons in the naturalgas,the PSRK model gives good agreement for the dew point pressure-vapor composition *** of the pure component parameters of the CSPhC EOS for heavy components to fit thevapor-liquid equilibrium(VLE)data has been proved to give significant promoting in ***,further improvement of a van der Waals EOS,such as SRK,PT and DG modelsfor the asymmetric systems by adjusting the three pure component properties,T_c, p_c and ?

关键词： equation of state natural gas vapor-liquid equilibria asymmetric systems

Nitrogen Contents on Tribological Properties of Magnetron Sputtered SICN Coatings

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材料热处理学报 2004年第05B期25卷 854-857页

作者： TIETUNSUN Y.Q.FU j.WEI h.j.DU Departmentofphysics ShanghaiJiaotongUniversityShanghaiChina／／SchoolofMechanicalandProductionEngineeringNanyangTechnologicalUniversitySingapore639798 SchoolofMechanicalandProductionEngineering NanyangTechnologicalUniversitySingapore639798／／SingaporeInstituteofManufacturingTechnologySingapore71NanyangDriveSingapore638075 SingaporeInstituteofManufacturingTechnology -Singapore71NanyangDrivesingapore638075

Silicon carbonitride (SiCN) coatings were deposited on silicon and tungsten carbide substrates by co-sputtering silicon and carbon in argon and nitrogen mixture atmosphere using magnetron-sputtering system. The effect of the N2 concentration, RF substrate bias voltage and target current on film deposition rate, roughness, adhesion, mechanical and tribological properties of coatings were investigated. The deposition rate was found to increase with the increasing nitrogen concentration. X-ray photoelectron spectroscopy analysis showed that high nitrogen concentration in the nitrogen-argon gas mixture enhanced the incorporation of C and N but reduced the incorporation of Si. SiCN coatings have good tribological properties at a N2 concentration of approximately 60%.

关键词： SiCN涂层磁控管溅射含氮量硬度磨损

Design and optimization of the composition and mechanical properties for non-equiatomic CoCrNi medium-entropy alloys

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journal of Materials Science & Technology 2023年第8期139卷 232-244页

作者： j.X.Yan Z.j.Zhang P.Zhang j.h.Liu h.Yu Q.M.hu j.B.Yang Z.F.Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China chool of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Shenyang University of TechnologyShenyang 111003China

The development of multi-principal element alloys(MPEAs,also called as high-or medium-entropy al-loys,hEAs/MEAs)provides tremendous possibilities for materials ***,designing MPEAs with desirable mechanical properties confronts great challenges due to their vast composition *** this work,we provide an essential criterion to efficiently screen the CoCrNi MEAs with outstanding strength-ductility *** negative Gibbs free energy difference△E_(FCC-BCC)between the face-centered cubic(FCC)and body-centered cubic(BCC)phases,the enhancement of shear modulus G and the decline of stacking fault energy(SFE)γ_(isf)are combined as three requisites to improve the FCC phase stability,yield strength,deformation mechanisms,work-hardening ability and ductility in the *** effects of chemical composition on△E_(FCC-BCC),G andγisf were investigated with the first principles calculations for Co_(x)Cr_(33)Ni_(67-x),Co_(33)Cr_(y)Ni_(67-y)and Co_(z)Cr_(66-z)Ni_(34)(0≤x,y≤67 and 0≤z≤66)*** on the essential criterion and the calculation results,the composition space that displays the neg-ative Gibbs free energy difference△E_(FCC-BCC),highest shear modulus G and lowest SFEγ_(isf)was screened with the target on the combination of high strength and excellent *** this context,the optimal composition space of Co-Cr-Ni alloys was predicted as 60 at.%-67 at.%Co,30 at.%-35 at.%Cr and 0 at.%-6 at.%Ni,which coincides well with the previous experimental evidence for Co_(55)Cr_(40)Ni_(5)*** valid-ity of essential criterion is further proved after systematic comparison with numerous experimental data,which demonstrates that the essential criterion can provide significant guidance for the quick exploitation of strong and ductile MEAs and promote the development and application of MPEAs.

关键词： Medium-entropy alloys First-principles calculations Phase stability Stacking-fault energy Strength Ductility

Simulating canopy stomatal conductance of winter wheat and its distribution using remote sensing information

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journal of Environmental Sciences 2001年第4期13卷 439-443页

作者： Zhang, j.-h. Fu, C.-b. Kanzawa, h. START Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The canopy stomatal movement, a plant physiological process, generally occurs within leaves but its influence on exchange of CO2, water vapor, and sensible heat fluxes between atmosphere and terrestrial ecosystem. Many studies have documented that the interaction between leaf photosynthesis and canopy stomatal conductance is obvious. Thus, information on stomatal conductance is valuable in climate and ecosystem models. In current study, a newly developed model was adopted to calculate canopy stomatal conductance of winter wheat in huang-huai-hai (h-h-h) Plain of China (31.5 - 42.7°N, 110.0 - 123.0°E). The remote sensing information from NOAA-AVhRR and meteorological observed data were used to estimate regional scale stomatal conductance distribution. Canopy stomatal conductance distribution pattern of winter wheat on March 18, 1997 was also presented. The developed canopy stomatal conductance model might be used to estimate canopy stomatal conductance in land surface schemes and seems can be acted as a boundary condition in regional climatic model runs.

关键词： Carbon dioxide Data reduction Ecosystems heat flux Meteorology Photosynthesis Physiology Plants (botany) Remote sensing Vapors

A fast-running method for blast load prediction shielding by a protective barrier

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Defence Technology（防务技术） 2020年第2期16卷 308-315页

作者： S.-h.Sung j.-W.Chong Agency for Defense Development Yuseong P.O.Box 35DaeJeon395-600South Korea

This study presents a simplified blast load prediction method on structures behind a protective *** proposed method is basically an empirical approach based on Kingery-Bulamsh(K-B)chart and finite element(FE)analysis *** this end,this study divides the structure into three regions by three critical *** loads at each critical point can be calculated based on K-B chart and an approximation according to FE analysis ***,peak reflected overpressure and impulse distributed on the structure can be approximately estimated by linearly connecting blast loads at each critical *** order to confirm a feasibility of the proposed method,a series of numerical simulations were carried *** simulation results were compared with FE analysis results which are presented in the open *** such comparisons,it was found that the proposed method is applicable to predict blast loads on structures behind a protective barrier.

关键词： Blast loads Protective barrier Shock wave Fast running model Kingery-Bulmash

Design of small-area multi-bit antifuse-type 1 kbit OTP memory

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journal of Central South University 2009年第3期16卷 467-473页

作者：李龙镇 LEE j h KIM T h jIN K h PARK M h hA P B KIM Y h Department of Electronic Engineering Changwon National University Department of Computer Science and Technology Yanbian University

A multi-bit antifuse-type one-time programmable （OTP） memory is designed, which has a smaller area and a shorter programming time compared with the conventional single-bit antifuse-type OTP memory. While the conventional antifuse-type OTP memory can store a bit per cell, a proposed OTP memory can store two consecutive bits per cell through a data compression technique. The 1 kbit OTP memory designed with Magnachip 0.18 μm CMOS （complementary metal-oxide semiconductor） process is 34% smaller than the conventional single-bit antifuse-type OTP memory since the sizes of cell array and row decoder are reduced. And the programming time of the proposed OTP memory is nearly 50% smaller than that of the conventional counterpart since two consecutive bytes can be compressed and programmed into eight OTP cells at once. The layout area is 214 μm× 327 μ,, and the read current is simulated to be 30.4 μA.

关键词： multi-bit OTP programming time antifuse memory data compression

Magnetic Properties of Ni Nanoparticles and Ni(C) Nanocapsules

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journal of Materials Science & Technology 2002年第2期18卷 99-100页

作者： Z.j.Li G.h.Wen 等 ShenyangNationalLaboratoryforMaterialsScienceandInternationalCentreforMaterialsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China DepartmentofPhysics H

Structure and magnetic properties of Ni nanoparticles and Ni(C) nanocapsules were studied. The carbon atoms hardly affect the lattice of Ni to form Ni-C solid solution or nickel carbides. The large thermal irreversibility in zero-field-cooled and zero-field magnetization curves indicates magnetic blocking with a wide energy barrier. Saturation magnetization, remanent magnetization and coercivity of Ni(C) nanocapsules decrease with increasing temperature.

关键词： Nanoparticles Nanocapsules Magnetic properties

A comparison study of Ce/La and Ca microalloying on the bio-corrosion behaviors of extruded Mg-Zn alloys

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journal of Magnesium and Alloys 2020年第4期8卷 1269-1280页

作者： j.h.Chu L.B.Tong Z.h.jiang D.N.Zou Q.j.Wang S.F.Liu h.j.Zhang School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Lab of Automobile Materials College of Materials Science and EngineeringJilin UniversityNanling CampusChangchun 130025China

The influences of Ca and Ce/La microalloying on the microstructure evolution and bio-corrosion resistances of extruded Mg-Zn alloys have been systematically investigated in the current *** with single Ca or Ce/La addition,the Ca-Ce/La cooperative microalloying results in an outstanding grain refinement,because the fine secondary phase particles effectively hinder the recrystallized grain *** coarse Ca2Mg6Zn3 phases promote the formation of Ca3(PO4)2 or hydroxyapatite particles during the immersion process and accelerate the dissolution of the corrosion product film,which destroys its integrity and results in the deterioration of anti-corrosive *** Ce/La elements can be dispersed within the conventional Mg7Zn3 phases,which reduce the internal galvanic corrosion between Mg matrix and the secondary phases,leading to an obvious improvement of corrosion ***,the Ca-Ce/La cooperative microalloying achieves a homogenous fine-grained microstructure and improves the protective ability of surface film,which will pave a new avenue for the design of biomedical Mg alloys in the coming future.

关键词： Extruded Mg-Zn alloy Ca and Ce/La microalloying Microstructure evolution Bio-corrosion behaviors