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中国有色金属学会会刊：英文版 2010年第S3期20卷 837-841页

作者： E.P.mASuKu h.mllER u.A.CuRlE P.C.PISTORIuS materials Science and manufacturing Council for Scientific Industrial ResearchPretoriaSouth Africa Department of materials Science and Engineering Carnegie Mellon UniversityPittsburghUSA

The corrosion behavior(in chloride medium) of the surface layer of SSm-hPDC plates of alloys 7075-T6 and 2024-T6 was compared with that of the wrought alloys 7075-T6 and *** testing was performed in deaerated 3.5%NaCl *** separate tests,the open-circuit potential was monitored in aerated 3.5% NaCl for 30 min after *** electrochemical tests show that there is no significant difference in the pitting potential of the wrought alloys and that of the Cu-enriched surfaces of the SSm-hPDC alloys.

关键词： semi-solid metal(SSm) forming wrought aluminium alloys alloy 7075 alloy 2024 corrosion surface liquid segregation

Decorating crystalline YFe_(2-x)Al_(x) on the mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy as “hydrogen pump” to realize fast de/hydrogenation

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Journal of materials Science & Technology 2024年第6期173卷 72-79页

作者： l.J.huang h.Wang l.Z.Ouyang m.Zhu h.J.lin School of materials Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional materials Jinan UniversityGuangzhou 510632China

mg-based amorphous alloys are one of the potential hydrogen storage materials but suffer from sluggish dehydrogenation/hydrogenation(de/hydrogenation)*** this work,as a new strategy,a hydrogen pump is built on the surface of amorphous alloys to solve this *** milling crystalline YFe_(2-x)Al_(x) hydrogen storage alloy with mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy,fine crystalline particles were seeded on amorphous alloy powder to form a“strawberry”*** to the TEm observation,a metallurgical bonding boundary formed between the mg-based amorphous matrix and the Y-Fe-Al crystalline *** microstructure and de/hydrogenation kinetics investigation,the“hydrogen pump”effect of the seeded crystalline alloy was confirmed,which makes it much easier for the hydrogen to dissociate on and diffuse through the surface of the mg-based amorphous *** such effect,the h absorption rate of mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy became almost eight times faster and it absorbs ~2.8 wt.% in 1 h at 130℃ under 4.5 mPa-h_(2).Further,fast hydrogenation can even achieve at 70℃ and the low-temperature dehydrogenation kinetics of the amorphous hydride can be also greatly *** present work proves that surface modification is of great importance for obtaining mg-based amorphous alloy with ideal hydrogen storage performance.

关键词： hydrogen storage mg-based amorphous alloy hydrogen pump Composite structure

Electromagnetoelastic behaviors of functionally graded piezoelectric solid cylinder and sphere

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Acta mechanica Sinica 2007年第1期23卷 55-63页

作者： h. l. Dai Y.m. Fu J.h. Yang Department of Engineering mechanics Hunan University Changsha 410082 China

Analytical studies on electromagnetoelastic behaviors are presented for the functionally graded piezoelectric material （FGPm） solid cylinder and sphere placed in a uniform magnetic field and subjected to the external pressure and electric loading. When the mechanical, electric and magnetic properties of the material obey an identical power law in the radial direction, the exact displacements, stresses, electric potentials and perturbations of magnetic field vector in the FGPm solid cylinder and sphere are obtained by using the infinitesimal theory of electromagnetoelasticity. Numerical examples also show the significant influence of material inhomogeneity. It is interesting to note that selecting a specific value of inhomogeneity parameter β can optimize the electromagnetoelastic responses, which will be of particular importance in modern engineering designs.

关键词： Functionally graded piezoelectric material (FGPm) Electromagnetoelastic Solid cylinder Solid sphere Perturbation of magnetic field vector

Interlayer distance effects on absorption coefficient and refraction index change in p-type double-δ-doped GaAs quantum wells

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Chinese Physics B 2019年第12期28卷 186-190页

作者： h Noverola-Gamas l m Gaggero-Sager O Oubram Instituto de Investigaciones en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos MorelosCuernavaca 62209Mexico Division Academica de Ingeniería y Arquitectura Universidad Juárez Autonoma de TabascoCunduacan 8660Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico

In the framework of the Thomas–Fermi(TF) approach, a model for the p-type double-δ-doped(DDD) system in Ga As is presented. This model, unlike other works in the literature, takes into account that the Poisson equation associated with the system is nonlinear. The electronic structure is calculated for heavy and light holes. The changes in the electronic structure result of the distance d between the doped layers are studied. In particular, the relative absorption coefficient as well as the relative refractive index change is calculated as a function of the incident photon energy for heavy holes. The effect of the interlayer distance exhibits, in the absorption coefficient, a red shift of the peak position and a decrease in amplitude when the distance increases. In addition, the relative refractive index change node has a red shift as well as the interlayer distance increases. The calculations show that the effect of the separation between layers has a greater influence on the linear terms. These results are very important for theoretical calculations and engineering of optical and electronic devices based in δ-doped Ga As.

关键词： double delta-doping p-type GaAs layers electronic structure Thomas–Fermi approach nonlinear optical properties

Colloidal(Gd0.98Nd0.02)2O3 nanothermometers operating in a cell culture medium within the first and second biological windows

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Journal of Rare Earths 2020年第5期38卷 483-491页

作者： m.l.Debasu h.Oliveira J.Rocha l.D.Carlos Department of Physics CICECO-Aveiro Institute of MaterilsUniversidade de Aveiro3810-193AveiroPortugal Department of Chemistry CICECO-Aveiro Institute of MaterialsUniversidade de Aveiro3810-193AveiroPortugal Department of Biology CESAMLaboratory of Biotechnology and CytomicsUniversidade de Aveiro3810-193AveiroPortugal

Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature readout at the nanoscale and real-time deep-tissue ***,the development of multifunctional and biocompatible luminescent nanothermometers operating within the optically transparent biological windows with high thermal sensitivity(>2.0%/K)remains ***,we present(Gd0.98Nd0.02)2O3 nanothermometers operated effectively within the first and second biological windows upon continuous-wave laser diode excitation at 808 *** thermometric parameters are defined by the relative changes in the emission intensities originating from the two Stark components of the 4 F3/2 level(R2 and R1)to the 4 I9/2(900-1000 nm),4 I11/2(1035-1155 nm)and 4 I13/2(1300-1450 nm)*** thermo metric parameters are evaluated for colloidal samples in a cell culture medium and powder samples,and the highest thermal sensitivity(2.18%/K at 298 K)is attained for the former in the first biological window(both the excitation and emission in the 800-965 nm range).The repeatability and temperature uncertainty are 99%and 1.2 K,*** nanothermometers are biocompatible with human mNT-1 melanoma and haCaT cells for 24 h of exposure and nanoparticle concentration up to 0.400 mg/ml,showing their potential for applications in nanomedicine,e.g.,intracellular imaging and temperature mapping.

关键词： Gd2O3 Nd3^+-doped nanoparticles luminescent nanothermometry Thermal sensitivity Cytotoxicity of nanoparticles Rare earths

Nonlinear transverse vibrations of a slightly curved beam carrying a concentrated mass

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Acta mechanica Sinica 2009年第6期25卷 871-882页

作者： E.zkaya m.Sarigül h.Boyaci Department of mechanical Engineering Celal Bayar UniversityMuradiye

In this study, a slightly curved Euler Bernoulli beam carrying a concentrated mass was handled. The beam was resting on an elastic foundation and simply supported at both ends. Effects of the concentrated mass on nonlin- ear vibrations were investigated. Sinusoidal and parabolic type functions were used as curvature functions. Equations of motion have cubic nonlinearities because of elongations during vibrations. Damping and harmonic excitation terms were added to the equations of motion. method of mul- tiple scales, a perturbation technique, was used for solving integro-differential equation analytically. Natural frequen- cies were calculated exactly for different mass ratios, mass locations, curvature functions, and linear elastic foundation coefficients. Amplitude-phase modulation equations were found by considering primary resonance case. Effects of nonlinear terms on natural frequencies were calculated. Frequency-amplitude and frequency-response graphs were plotted. Finally effects of concentrated mass and chosen curvature function on nonlinear vibrations were investigated.

关键词： Nonlinear vibrations . Slightly curved beamNonlinear elastic foundation. Concentrated mass

The spin-isospin decomposition of the nuclear symmetry energy from low to high density

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Chinese Physics C 2020年第5期44卷 114-118页

作者： Wenmei Guo m.Colonna V.Greco u.lombardo h.-JSchulze Department of Physics Anhui Normal UniversityWuhu 241000China laboratori Nazionali del Sud(INFN) Via S.Sofia 6295123 CataniaItaly Dipartimento di Fisica e Astronomia Via S.Sofia 6495123 CataniaItaly INFN Sezione di CataniaVia S.Sofia 6295123 CataniaItaly

The energy per particle BA in nuclear matter is calculated up to high baryon density in the whole isospin asymmetry range from symmetric matter to pure neutron *** results,obtained in the framework of the Brueckner-hartree-Fock approximation with two-and three-body forces,confirm the well-known parabolic dependence on the asymmetry parameterβ=(N?Z)/A(β^2 law)that is valid in a wide density *** investigate the extent to which this behavior can be traced back to the properties of the underlying interaction,aside from the mean field approximation,the spin-isospin decomposition of BA is *** indications suggest that theβ^2 law could be violated at higher densities as a consequence of the three-body *** raises the problem that the symmetry energy,calculated according to theβ^2 law as a difference between BA in pure neutron matter and symmetric nuclear matter,cannot be applied to neutron *** should return to the proper definition of the nuclear symmetry energy as a response of the nuclear system to small isospin imbalance from the Z=N nuclei and pure neutron matter.

关键词： symmetry energy nuclear interaction spin-isospin decomposition nuclear matter

Size Dependent Physical Properties of Nanostructured α-Fe_2O_3 Thin Films Grown by Successive Ionic layer Adsorption and Reaction method for Antibacterial Application

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Journal of materials Science & Technology 2015年第1期31卷 1-9页

作者： A.u.ubale m.R.Belkhedkar Nanostructured Thin Film materials laboratory Department of PhysicsGovt.Vidarbha Institute of Science and Humanities Department of Physics Shri Shivaji College

Thin films of nanostructured α-FeOwith thickness of 1 56,203 and 251 nm were deposited by successive ionic layer adsorption and reaction(SIlAR) method onto glass substrates using FeCl-6hO and NaOh as cationic and anionic *** X-ray diffraction studies revealed that,α-FeOthin films are nanocrystalline in nature with rhombohedral *** morphological properties were investigated by field emission scanning electron and atomic force *** optical studies showed that α-FeOexhibits direct as well as indirect optical band gap *** electrical resistivity of α-FeOat 305 K decreases from 11.76×102 to9.46 × 10~2 Ω cm as film thickness increases from 156 to 251 *** thermo-emf measurements confirmed that α-FeOexhibits n-type *** nanocrystalline α-FeOexhibits antibacterial character against Staphylococcus aureus and its efficiency increases from 37.50%to 87.50%depending on crystallite size.

关键词： Thin films Nanostructures AFm(atomic force microsc

Effect of interlayer addition on microstructure and mechanical properties of NiTi/stainless steel joint by electron beam welding

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Journal of materials Science & Technology 2021年第2期61卷 16-24页

作者： h.Niu h.C.Jiang m.J.Zhao l.J.Rong CAS Key laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of materials Science and Engineering University of Science and Technology of ChinaHefei230026China

NiTi/Stainless Steel(SS) sheets have been welded via a vacuum electron beam welding process, with three methods(offsetting electron beam to SS side without interlayer, adding Ni interlayer and adding Fe Ni interlayer), to promote mechanical properties of the Ni Ti/SS joints. The joints with different interlayers are all fractured in the weld zone near the Ni Ti side, which is attributed to the enrichment of intermetallic compounds including Fe2 Ti and Ni3 Ti. The fracture mechanisms of different joints are strongly dependent on the types of interlayers, and the joints without interlayer, adding Ni interlayer and adding Fe Ni interlayer exhibit cleavage fracture, intergranular fracture and mixed fracture composed of cleavage and tearing ridge, respectively. Compared with the brittle laves phase Fe2 Ti, Ni3 Ti phase can exhibit certain plasticity, block the crack propagation and change the direction of crack propagation. The composite structure of Ni3 Ti and Fe2 Ti will be formed when the Fe Ni alloy is taken as the interlayer, which provides the joint excellent mechanical properties, with rupture strength of 343 mPa.

关键词： NiTi Stainless steel Electron beam welding Interlayer mechanical property

Physics design of 14 meV neutron generator facility at the Institute for Plasma Research

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Plasma Science and Technology 2023年第12期25卷 115-121页

作者： h l SWAmI S VAlA m RAJPuT m ABhANGI Ratnesh KumAR A SAXENA Rajesh KumAR Institute for Plasma Research Gandhinagar 382428India homi Bhabha National Institute Training School ComplexMumbai 400094India

A high energy and high yield neutron source is a prime requirement for technological studies related to fusion reactor development. It provides a high-energy neutron environment for small-scale fusion reactor components research and testing such as tritium breeding, shielding, plasmafacing materials, reaction cross-section data study for fusion materials, etc. Along with ITER participation, the Institute of Plasma Research, India is developing an accelerator-based 14 meV neutron source with a yield of 10^(12)n s^(-1). The design of the source is based on the deuterium–tritium fusion reaction. The deuterium beam is accelerated and delivered to the tritium target to generate 14 meV neutrons. The deuterium beam energy and tritium availability in the tritium target are the base parameters of the accelerator-based neutron source design. The paper gives the physics design of the neutron generator facility of the Institute for Plasma Research. It covers the requirements, design basis, and physics parameters of the neutron generator. As per the analytical results generator can produce more than 1 × 10^(12)n s^(-1)with a 110 keV D^(+) ion beam of 10 mA and a minimum 5 Ci tritium target. however, the detailed simulation with the more realistic conditions of deuteron ion interaction with the tritium titanium target shows that the desired results cannot be achieved with 110 keV. The safe limit of the ion energy should be 300 keV as per the simulation. At 300 keV ion energy and 20 mA current, it reaches 1.6 × 10^(12)n s^(-1). moreover, it was found that to ensure sufficiently long operation time a tritium target of more than 20 Ci should be used. The scope of the neutron source is not limited to the fusion reactor research studies, it is extended to other areas such as medical radioisotopes research, semiconductor devices irradiations, and many more.

关键词： neutron generator neutronics accelerator physics design nuclear fusion