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Journal of Materials Science & Technology 2021年第21期80卷 244-258页

作者： S.y.Wang y.Sun C.y.Cui X.F.Sun y.Z Zhou y.M.Ma H.L.An Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Harbin Welding Institute China Academy of Machinery Science and TechnologyHarbin 150028China

Post-bond heat treatment(PBHT) applied to a transient liquid phase(TLP) bonding joint is an effective approach to remove the brittle borides and improve its ***,we proposed two types of PBHT strategies to obtain a TLP bonded γ'-strengthened Co-based single crystal superalloy,and the microstructural characteristics and tensile properties of the two heat treated joints were compared to identify the optimal PBHT *** evolution of the brittle boride in the joint after the PBHT was studied by using in-situ *** experimental results allowed to provide a theoretic model to quantitatively evaluate the distribution of the brittle phase after the optimal PBHT and analyze the joint fractures to understand the failure *** obtained results revealed that a post-bond solid solution treatment performed to the joint at a high temperature(over 1275℃) could decrease the area fraction of the boride from 7.2 % to 1.4 % and increase the elongation from 1.9 % to 7.8 %.This work emphasizes the relevance of solid solution temperature when a PBHT strategy is applied.

关键词： Transient liquid phase(TLP) γ'-strengthened co-based single crystal superalloy Heat treatment sequence Brittle boride Tensile property

Quaternion methods and models of regular celestial mechanics and astrodynamics

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Applied Mathematics and Mechanics(English Edition) 2022年第1期43卷 21-80页

作者： y.N.CHELNOKOV Institute of Precision Mechanics and Control Russian Academy of SciencesSaratov410031Russia

This paper is a review,which focuses on our work,while including an analysis of many works of other researchers in the field of quaternionic *** regular quaternion models of celestial mechanics and astrodynamics in the Kustaanheimo-Stiefel(KS)variables and Euler(Rodrigues-Hamilton)parameters are *** models are derived by the quaternion methods of mechanics and are based on the differential equations of the perturbed spatial two-body problem and the perturbed spatial central motion of a point *** paper also covers some applications of these *** and Scheifele are known to have doubted that quaternions and quaternion matrices can be used efficiently to regularize the equations of celestial ***,the author of this paper and other researchers refuted this point of view and showed that the quaternion approach actually leads to efficient solutions for regularizing the equations of celestial mechanics and *** paper presents convenient geometric and kinematic interpretations of the KS transformation and the KS bilinear relation proposed by the present *** general(compared with the KS equations)quaternion regular equations of the perturbed spatial two-body problem in the KS variables are *** equations are derived with the assumption that the KS bilinear relation was not *** main stages of the quaternion theory of regularizing the vector differential equation of the perturbed central motion of a point particle are presented,together with regular equations in the KS variables and Euler parameters,derived by the aforementioned *** also present the derivation of regular quaternion equations of the perturbed spatial two-body problem in the Levi-Civita variables and the Euler parameters,developed by the ideal rectangular Hansen coordinates and the orientation quaternion of the ideal coordinate *** paper also gives new results using quaternionic methods in the pertur

关键词： celestial mechanics astrodynamics perturbed spatial two-body problem central motion regularization Levi-Civita and Kustaanheimo-Stiefel(KS)variables Euler parameter quaternion

Helicobacter pylori infection

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World Journal of Gastroenterology 2000年第1期6卷 20-31页

作者： Vandenplas y Academisch Ziekenhuis Kinderen Free University of BrusselsBrusselsBelgium

IS THERE ANyTHING NEW?Helicobacter pylori has been for many years aforgotten bacterium,since the first report on thisspiral organism dated from the 19th *** as in 1906,an association between a spiralorganism and gastr... 详细信息

关键词： Subject headings Helicobacter pylori gastritis Helicobacter infection

Enhanced pitting corrosion resistance of a Zr-based metallic glass by ultraviolet light irradiation

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Journal of Iron and Steel Research International 2023年第8期30卷 1642-1649页

作者： Z.Chen D.P.Wang S.Wang y.X.Geng y.X.Guo y.C.Wu Z.G.Liu y.y.Zhang y.X.Wang School of Materials Science and Engineering Jiangsu University of Science and Technology.Zhenjiang 212003JiangsuChina School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina

The influence of ultraviolet light irradiation on the pitting corrosion performance of a Zr_(2)Ni metallic glass was examined using electrochemical methods and immersion test in 0.05 mol/L NaCl *** the results of potentiostatic polarization,the pitting potential of the ultraviolet light-irradiated sample shifted positively with a value of~300 mV,revealing the enhanced pitting corrosion resistance of the *** corrosion morphology after the immersion test also demonstrated lower degree of corrosion damage and improved pitting resistance of the sample with ultraviolet light irradiation.X-ray photoelectron spectroscopy analysis revealed more zirconium enrichment in the passive film and no chloride ions adsorption for the samples with ultraviolet irradiation,accounting for the suppression of the pit generation and *** findings indicate that ultraviolet light irradiation improves the pitting corrosion resistance of the Zr-based metallic glasses,which are promising structural materials to be used in corrosion environments with high ultraviolet irradiation.

关键词： Metallic glass Pitting-Corrosion Ultraviolet light irradiation Passive film

Fluctuation theorem for entropy production at strong coupling

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Chinese Physics B 2020年第1期29卷 175-180页

作者： y y Xu J Liu M Feng Faculty of Science Kunming University of Science and TechnologyKunming 650500China Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Fluctuation theorems have been applied successfully to any system away from thermal equilibrium,which are helpful for understanding the thermodynamic state *** investigate fluctuation theorems for strong coupling between a system and its reservoir,by path-dependent definition of work and heat satisfying the first law of *** present the fluctuation theorems for two kinds of entropy *** is the informational entropy production,which is always non-negative and can be employed in either strong or weak coupling *** other is the thermodynamic entropy production,which differs from the informational entropy production at strong coupling by the effects regarding the *** find that,it is the negative work on the reservoir,rather than the nonequilibrium of the thermal reservoir,which invalidates the thermodynamic entropy production at strong *** results indicate that the effects from the reservoir are essential to understanding thermodynamic processes at strong coupling.

关键词： fluctuation theorem entropy production strong coupling

Synthesis and characterization of y and Dy co-doped ceria solid electrolytes for IT-SOFCs:a microwave sintering

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Rare Metals 2021年第11期40卷 3329-3336页

作者： Ch.Madhusudan Venkataramana Kasarapu Madhuri Chittimadula y.Suresh Reddy C.Vishnuvardhan Reddy Department of Physics Osmania UniversityHyderabadTelangana 500007India

In this communication,the electrical conductivities and thermal expansion studies of microwave sintered co-doped ceria Ce_(0.8)y_(0.2-x)Dy_(x)O_(2-δ)(x=0,0.05,0.10,0.15 and 0.20) solid electrolyte materials for intermediate temperature solid oxide fuel cells(IT-SOFCs)synthesized by sol-gel auto-combustion method were *** sintering at 1300℃ for 30 min was used for making dense powder *** relative densities of all the samples are noticed above 95%.Raman spectrum was characterized by the presence of a very strong band near 460 cm^(-1),which along with X-ray diffraction(XRD) analysis ascertain the sample formation with a single-phase cubic fluorite *** lattice parameter values were calculated from XRD *** images show nearly uniform grains with distinct grain *** thermal expansion coefficients(TECs) are found to vary linearly with temperature and were measured in the range from 14.15 to 13.20×10^(-6)℃^(-1).The investigation on total ionic conductivity(TIC) was executed with variation in dopant concentration and relative oxygen *** impedance analysis reveals that the sample Ce_(0.80)y_(0.10)Dy_(0.10)O_(2-δ) displays the highest TIC,i.e.,7.5×10^(-3) S·cm^(-1) at 500℃ and minimum activation energy 0.90 eV compared to *** the highest TIC and minimum activation energy,the Ce_(0.80)y_(0.10)Dy_(0.10)O_(2-δ)might be the possible material as the solid electrolyte in intermediate temperature SOFCs.

关键词： Microwave sintering Ionic conductivity Co-doped ceria Solid electrolyte Intermediate temperature solid oxide fuel cells

Enhanced thermoelectric performance of spark plasma sintered p-type Ca_(3-x)y_(x)Co_(4)O_(9+δ)systems

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Journal of Materials Science & Technology 2020年第20期52卷 212-222页

作者： J.S.Cha D.H.Kim H.y.Hong K.Park Faculty of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul05006Republic of Korea

Highly textured dense Ca3-xyxCo4 O9+δ(0≤x≤0.3)samples were fabricated by combining sol-gel process with spark plasma sintering(SPS).y^3+substitution for Ca^2+simultaneously increased the Seebeck coefficient and reduced the thermal *** latter was attributed to the increase in lattice anharmonicity,structural distortion,and grain boundary area,which enhanced the phonon ***2.7y0.3Co4 O9+δshowed the largest dimensionless figure-of-merit(ZT=0.194)at 1073 K because it had the largest Seebeck coefficient and the lowest thermal *** ZT value was 55%larger than that of undoped Ca3 Co4 O9(0.125 at 1073 K).Therefore,y^3+substitution,sol-gel powder synthesis,and SPS are highly effective for enhancing the thermoelectric prope rties of Ca_(3)Co_(4)O_(9).

关键词： Electrical conductivity Ca_(3)Co_(4)O_(9) Thermoelectric properties Seebeck coefficient Thermal conductivity Spark plasma sintering

Absorption of laser radiation in ultracold plasma

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Chinese Physics B 2016年第10期25卷 128-131页

作者： N y Shaparev Institute of Computational Modeling Russian Academy of Sciences National Research Tomsk State University

In this paper, we analyze the spectral behavior(optical thickness, shape and linewidth) of laser radiation absorption under the correlation heating of ions in an ultracold plasma. The Voigt formula is used to find the absorption *** spectral line width is shown to grow with time while the optical thickness reduces. Our modeling results are in good agreement with the experimental findings reported in the literature.

关键词： absorption laser radiation ultracold plasma

Tsallis agegraphic dark energy model with the sign-changeable interaction

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Communications in Theoretical Physics 2020年第1期72卷 96-101页

作者： y D Xu School of Science Jiangsu Ocean UniversityLianyungang 222005China

In this paper,we study the evolution of a spatially flat universe composed of Tsallis agegraphic dark energy(TADE)and a pressureless dark matter(DM),by assuming that there is a signchangeable interaction between TADE and *** density,deceleration parameter and the equation of state parameters(EoS)show satisfactory behaviors in the *** analysis we find that the accelerated expansion of the universe can be achieved at the late time if model parametersδ>2 and-2/3y means of statefinder diagnostic and w–w’analysis.

关键词： Tsallis agegraphic dark energy cosmological evolution statefinder w–w’analysis

Computer study of the spectral characteristics of the disperse water methane system

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Chinese Physics B 2013年第12期22卷 238-242页

作者： A.y.Galashev Institute of Industrial Ecology Ural Branch Russian Academy of Sciences 62099S. Kovalevskaya Str. 20 Yekaterinburg Russia

The interaction of water clusters that adsorbed methane molecules with infrared radiation is studied by molecular dynamics. The presence of methane molecules in the disperse water system leads to an increase in absorption and emission of infrared radiation and a strong depletion of the Raman spectrum. In this case, the reflection coefficient of a monochromatic plane electromagnetic wave increases and its frequency spectrum significantly changes. The comparison of experimental data for similar characteristics of water, methane, or their mixtures is presented.

关键词： adsorption methane water cluster infrared and Raman spectra