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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.E.Penionzhkevich v.v.Samarin S.m.Lukyanov v.A.maslov m.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of Experimental methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer m.vR with beams of ^(48)Ca(280 m.v)and ^(56)Fe(320 and 400 m.v)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation *** analysis of the obtained experimental data was carried out within the model of m.ving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of m.ving sources time-dependent Schrodinger equation

Electrical Properties and Local Domain Structure of LiNbO_3 Thin Film Grown by Ion Beam Sputtering method

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Acta metallurgica Sinica(English Letters) 2013年第5期26卷 630-634页

作者： v.Ievlev v.Shur m.Sumets A.Kostyuchenko voronezh State University Ferroelectric Laboratory IPAm Ural State University voronezh Institute of the State Fire Service of Russian Emergencies ministry

The nanocrystalline ferroelectric LiNbO3 films on（001） Si substrates with the random orientation of polycrystalline grains and the predominance of the grains with lateral orientation of the polar axis were grown using the ion beam sputtering method. The remanent polarization and the coercive field are 12 μC/cm2and 29 kv/cm, respectively. The thermal annealing leads to the coarsening of the grains. The appearance of the ＂local texture,＂ which gives rise to the unipolarity of the heterostructures caused by the predominance of the one direction in the vertical component of the spontaneous polarization, is investigated.

关键词： LiNbO3 thin films Ferroelectrics Domain structure

Reissner-Nordstrom-de-Sitter-type Solution by a Gauge Theory of Gravity

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Chinese Physics Letters 2008年第10期25卷 3570-3573页

作者： v. Enache Camelia Popa v. Paun m. Agop Department of Theoretical Physics Faculty of Physics Al.I.Cuza University Blvd. Carol No.l 700506 Iasi Romania Department of Physics Faculty of Applied Sciences Politehnica University of Bucharest I 313 Splaiul lndependentei Street 060042 Bucharest Romania Department of Physics Gh. Asachi Technical University Blvd. Mangeron 700029 Iasi Romania Department of Physics University of Athens Athens 15771 Greece

We use the theory based on a gravitational gauge group （Wu＇s model） to obtain a spherical symmetric solution of the field equations for the gravitational potential on a minkowski spacetime. The gauge group, the gauge covariant derivative, the strength tensor of the gauge feld, the gauge invariant Lagrangean with the cosmological constant, the field equations of the gauge potentiaIs with a gravitational energy-momentum tensor as well as with a tensor of the field of a point like source are determined. Finally, a Reissner-Nordstrom-de Sitter-type metric on the gauge group space is obtained.

关键词： WEYL-DIRAC THEORY GRAvITATIONAL-FIELD EQUATIONS INvARIANCE DUALITY gravitational fields DUALITY Gravity Tensor FIELD EQUATIONS gauge theory invariance

Solid solution strengthening in multicomponent fcc and bcc alloys:Analytical approach

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Progress in Natural Science:materials International 2021年第1期31卷 95-104页

作者： m.Lugovy v.Slyunyayev m.Brodnikovskyy Institute for Problems of materials Science

Based on virtual solvent concept, novel methods are developed to determine interatomic distance, atomic size misfit, and elastic modulus misfit in multicomponent alloys with components having the crystal structure differing from that of the alloy. The combination of the different methods results in a number of models to calculate solid solution strengthening. These models are assessed with view point of the best fit to experimental data. The models giving the most reliable strengthening prediction can be used for an evolutionary design of strong and stable multicomponent alloys.

关键词： multicomponent alloy Solid solution strengthening model Atomic size misfit Elastic modulus misfit

Electricity Potential Generation by Wheat Straw from mexicali valley,mexico

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Electricity Potential Generation by Wheat Straw from Mexical...

Error bounds of a quadrature formula with multiple nodes for the Fourier-Chebyshev coefficients for analytic functions

2011 World Congress on Engineering and Technology(CET 2011)

作者： Conrado García Gisela montero marcos A.Coronado Armando Pérez Ana m.vázquez Engineering Institute Universidad Autonoma de Baja California

During 2009, 48% of farmland in mexicali valley （mv）, Baja California, mexico was used for growing wheat for grain, it means 88,439 Ha. Although wheat is a priority crop in Baja California, farmers of mv do not have options for the proper disposal of wheat straw generated as a remnant of the crop of wheat. Because of this, wheat straw is considered a problematic and worthless waste, and it is discarded through a burning in situ. 85% of the straw is burned. This practice is used to dispose 548,764 t of waste. This work analyses the feasibility of exploitation of 6.86 PJ of heat energy per cycle from agricultural waste biomass to be used as fuel for power generation. The results indicate that the potential for electricity production accounts for 9% of the installed capacity of geothermal park Cerro Prieto （720 mW） located in mv and 6.6 times the installed capacity of the wind farm La Rumorosa （10 mW）, located in the municipality of Tecate.

关键词： biofuels energy resource power generation wheat straw

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Science China mathematics 2019年第9期62卷 1657-1668页

作者： Aleksandar v.■ miodrag m.■ Department of mathematics Faculty of Mechanical Engineering University of Beograd

Three kinds of effective error bounds of the quadrature formulas with multiple nodes that are generalizations of the well-known micchelli-Rivlin quadrature formula, when the integrand is a function analytic in the regions bounded by confocal ellipses, are given. A numerical example which illustrates the calculation of these error bounds is included.

关键词： error bound quadrature formula with multiple nodes analytic function

Synthesis and performance of Zn–Ni–P thin films

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Chinese Physics B 2015年第3期24卷 259-268页

作者： v.Soare m.Burada I.Constantin m.Ghita v.Constantin F.miculescu A.m.Popescu New materials and Technologies Laboratory National Research and Development Institute for Nonferrous and Rare Metals-IMNR Institute of Physical Chemistry "Ilie murgulescu" Laboratory of Molten Salts University Polytehnica of Bucharest Center of Biomaterials (BIOMAT)

The electroplating of Zn–Ni–P thin film alloys from a sulfate bath containing phosphoric and phosphorous acid was investigated. The bath composition and the deposition parameters were optimized through Hull cell experiments, and the optimum experimental conditions were determined（p H = 2, temperature = 298–313 K, zinc sulfate concentration =30 g·L^-1, EDTA concentration = 15 g·L^-1, and current density = 1.0–2.0 A·dm^-2）. The SEm analysis of the coating deposited from the optimum bath revealed fine-grained deposits of the alloy in the presence of EDTA. Optical microscopy analysis indicated an electrodeposited thin film with uniform thickness and good adhesion to the steel substrate. The good adherence of the coatings was also demonstrated by the scratch tests that were performed, with a maximum determined value of 25 N for the critical load. Corrosion resistance tests revealed good protection of the steel substrate by the obtained Zn–Ni–P coatings, with values up to 85.89% for samples with Ni contents higher than 76%. The surface analysis of the thin film samples before and after corrosion was performed by X-ray photoelectron spectroscopy（XPS）.

关键词： thin film corrosion electrochemistry surface

Relativistic Landau quantization in the spiral dislocation spacetime

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Communications in Theoretical Physics 2021年第2期73卷 68-72页

作者： A v D m maia K Bakke Departamento de Fisica Universijade Federal da ParaibaCaixa Postal 500858051-900Joao PessoaPBBrazil

We analyse the interaction of a relativistic electron with a uniform magnetic field in the spiral dislocation *** show that analytical solutions to the Dirac equation can be obtained,where the spectrum of energy corresponds to the relativistic Landau *** also analyse the influence of the spiral dislocation on the relativistic Landau levels by showing that there exists an analogue of the Aharonov–Bohm effect for bound states.

关键词： spiral dislocation spacetime relativistic Landau quantization Aharonov-Bohm effect relativistic wave equations Dirac equation

microstructure,Tensile and Impact Toughness Properties of Friction Stir Welded mild Steel

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Journal of Iron and Steel Research International 2010年第10期17卷 68-74页

作者： A K Lakshminarayanan v Balasubramanian m Salahuddin Department of manufacturing Engineering Annamalai University Clean Technology Division Ministry of Environment and Forests

microstructure, tensile and impact toughness properties and fracture location of friction stir welded AISI 1018 mild steel were revealed. The AISI 1018 mild steel plates with thickness of 5 mm were friction stir welded by tungsten based alloy tool with tool rotational speed of 1 000 r/min and welding speed of 50 ram/rain. Tensile strength of stir zone is higher （8%） compared to that of the base metal. This may be due to the formation of finer grains in the weld nugget region under the stirring action of the rotating tool. The ductility and impact toughness of the joints are decreased compared to those of the base metal owing to the inclusion of tungsten particles in the weld region.

关键词： friction stir welding tensile property impact toughness mildsteel

Preparation of crystalline mg(OH)2 nanopowder from serpentinite mineral

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International Journal of mining Science and Technology 2018年第3期28卷 499-503页

作者： v. Sirota v. Selemenev m. Kovaleva I. Pavlenko K. mamunin v. Dokalov m. Yapryntsev Belgorod State National Research University Belgorod 308015 Russia voronezh State University Voronezh 394006 Russia Belgorod State Technological University named after v.G. Shoukhov Russia

In this paper we describe a route to produce crystalline mg（OH）2 nanopowders from serpentinite ore distributed in the Halilovskiy array （Russia, Orenburg region）. An efficient extraction route consisting of treatment on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for mg（OH）2 precipitation was demonstrated. In this study, crystalline mg（OH）2 nanopowders have been synthesized by solvothermal reaction method using （mg（NO3）2·6H2O） which were obtained from serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-active substance. microstructure and phase composition of samples were investigated employing scanning electron microscopy （SEm） and transmission electron microscopy （TEm）, X-ray phase analysis （XRD）, and inductively coupled plasma optical emission spectroscopy （ICP-OES）. XRD reveals that mg（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline mg（OH）2 nanopowders exclusively consist of lamellar-like structures and the sizes of mg（OH）2 are 30-265 nm length or width.

关键词： Serpentinite Nitric acid leaching magnesium hydroxide Solvothermal reaction method Crystalline mg(OH)2 nanopowder