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Chinese Journal of Chemical engineering 2021年第6期34卷 198-207页

作者： sunita Malik Poonam Jangra Darolia s.k.Garg v.k.sharma Department of Chemistry Maharshi Dayanand UniversityRohtakHaryanaIndia J.C.Bose University of science and Technology YMCAFaridabadHaryanaIndia

The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and *** densities of binary diesel(2)+1-alkanols(C_(3) or C_(4))(3)and ternary Jatropha curcas biodiesel(1)+diesel(2)+1-alkanols(C_(3)or C_(4))(3)blends have been reported over full range of composition at temperatures within range 288.15 to 313.15 *** densities of Jatropha curcas biodiesel(1)+diesel or 1-alkanols(C_(3) or C_(4))(2)blends have been measured at 313.15 *** molar volumes,v^e,v^e_(123)of binary and ternary blends were calculated from the measured data and the derived properties were correlated to composition using Redlich-kister equation.A reasonable agreement was found between the measured and estimated ***,densities and excess molar volumes data were reasoned to discuss molecular interactions taking into consideration effect of composition and temperature.

关键词： Jatropha curcas biodiesel Diesel Alcohols Blends Density excess molar volumes

Understanding the mechanisms of friction stir welding based on computer simulation using particles

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Defence Technology（防务技术） 2018年第6期14卷 643-656页

作者： A.Yu.smolin e.v.shilko s.v.Astafurov e.A.kolubaev G.M.eremina s.G.Psakhie Institute of strength Physics and Materials science sB RAs Tomsk634055Russia Tomsk state University Tomsk634050Russia skolkovo Institute of science and Technology Skolkovo143025Russia

Friction stir welding(FsW) is a novel technique for joining different materials without melting. In FsW the welded components are joined by stirring the plasticized material of the welded edges with a special rotating pin plunged into the material and moving along the joint line. From the scientific point of view,the key role of the FsW processes belongs to formation of the special plasticized conditions and activation of physical mechanisms of mixing the materials in such conditions to produce the strong homogeneous weld. But it is still a lack of complete understanding of what are these conditions and *** paper is devoted to understanding the mechanisms of material mixing in conditions of FsW based on a computer simulation using particles. The movable cellular automaton method(MCA), which is a representative of the particle methods in mechanics of materials, was used to perform all ***, material flow including material stirring in FsW is simulated using computational fluid mechanics or smoothed particle hydrodynamics, which assume that the material is a continuum and does not take into account the material structure. MCA considers a material as an ensemble of bonded particles. Breaking of inter-particle bonds and formation of new bonds enables simulation of crack nucleation and healing, as well as mass mixing and *** paper consists of two main parts. In the first part, the simulations in 2 D statements are performed to study the dynamics of friction stir welding of duralumin plates and influence of different welding regimes on the features of the material stirring and temperature distribution in the forming welded joints. It is shown that the ratio of the rotational speed to the advancing velocity of the tool has a dramatic effect on the joint quality. A suitable choice of these parameters combined with additional ultrasonic impact could considerably reduce the number of pores and microcracks in the weld without significa

关键词： Friction stir welding Plastic flow Deformation mechanisms simulation Particle method

electron-beam Treatment of Tungsten-free TiC/NiCr Cermet Ⅰ:Influence of subsurface Layer Microstructure on Resistance to Wear during Cutting of Metals

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Journal of Materials science & Technology 2005年第3期21卷 427-429页

作者： v.e.Ovcharenko BaohaiYU s.G.Psakhie InstituteofstrengthPhysicsandMaterialsscience SiberiaBranchRussianAcademyofSciences2/1AcademicheskyPr.Tomsk634021Russia InstituteofMetalResearch ChineseAcademyofSciences72WenhuaRoadShenyang110016China

An experimental investigation were performed on the effect of the impulse electron-beam irradiation upon microstruc-ture of the surface layer and on wear resistance of a cutting tool for sintered TiC/NiCr cermet. The results showed that the surface electron-beam treatment of the TiC/NiCr cermet is an efficient method for investigating the mi-crostructure and phase composition in the surface layer of the powder composite and there are optimal regimes of electron-beam treatment, which ensure a substantial increase in the resistance of the cermet to wear during cutting of metals.

关键词： Cermet TiC/NiCr electron-beam treatment Microstructure Wear resistance

A spectral Atlas of F and G stars

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Chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 279-283页

作者： v.G.klochkova GangZhao v.e.Panchuk s.v.ermakov NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 specialAstrophysicalObservatoryRussianAcademyofsciences NizhnijArkhyzKarachai-Cherkessia369167Russia

We present an atlas of a group of bright stars in the range of spectral classes F–G and luminosity classes I–v. The spectra were obtained with spectral resolution R ~ 15 000 within spectral region 4500–6620?. Typical spectra of stars with different metallicity [Fe/H] are included. We also show the digital version of the spectral data in FITs format.

关键词： stars: atlas stars: spectral class stars: F-G type

Nanoscale deformation of multiaxially forged ultrafine-grained Mg-2Zn-2Gd alloy with high strength-high ductility combination and comparison with the coarse-grained counterpart

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Journal of Materials science & Technology 2018年第2期34卷 311-316页

作者： k. Li v.s.Y.Injeti P. Trivedi L.e. Murr R.D.k. Misra Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso 500 W. University Avenue El Paso TX 79968-0521 USA

Cold processing of magnesium （Mg） alloys is a challenge because Mg has a hexagonal close-packed （HCP） lattice with limited slip systems, which makes it difficult to plastically deform at low temperature. To address this challenge, a combination of annealing of as-cast alloy and multi-axial forging was adopted ro obtain isotropic ultrafine-grained （UFG） structure in a lean Mg-2Zn-2Gd alloy with high strength （yield strength： ~227 MPa）-high ductility （% elongation：～30%） combination. This combination of strength and ductility is excellent for the lean alloy, enabling an understanding of deformation processes in a formable high strength Mg-rare earth alloy. The nanoscale deformation behavior was studied via nanoindentation and electron microscopy, and the behavior was compared with its low strength （yield strength：～46 MPa） - low ductility （% elongation：～7%） coarse-grained （CG） counterpart. In the UFG alloy, extensive dislocation slip was an active deformation mechanism, while in the CG alloy, mechanical twinning occurred. The differences in the deformation mechanisms of UFG and CG alloys were reflected in the discrete burst in the load-displacement plots. The deformation of Mg-2Zn-2Gd alloys was significantly influenced by the grain structure, such that there was change in the deformation mechanism from dislocation slip （non-basal slip） to nanoscale twins in the CG structure. The high plasticity ofUFG Mg alloy involved high dislocation activity and change in activation volume.

关键词： Magnesium alloy Ultrafine-grained Nanoscale deformation

Numerical forecasting surge in a piping of compressor shops of gas pipeline network

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Journal of Zhejiang University-science A(Applied Physics & engineering) 2007年第11期8卷 1775-1788页

作者： seLeZNev v. e. PRYALOv s. N. Physical & Technical Center Joint Stock Company Sarov 607180 Russia

This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFs) installed on a piping of compressor shops servicing gas pipelines. The stability of superchargers operation is assessed in relation to the phenomenon of surge. solution of this problem amounts to the development and numerical analysis of a set of ordinary differential equations. The set describes transmission of gas through a compressor shop as a fluid dynamics model with lumped parameters. The proposed method is oriented to wide application by specialists working in the gas industry. The practical application of this method can use all-purpose programming and mathematical software available to specialists of gas companies.

关键词： Gas pipelines Compressor station Centrifugal supercharger (CFs) surge Numerical simulation

evaluation of vsk separation in the classification of two mineralogically different iron ore fines

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 260-270页

作者： Deepak Nayak Tonmoy kundu Nilima Dash shiva kumar I.Angadi s.k.Chaurasiya G.e.sreedhar T.v.s.subrahmanyam swagat s.Rath Mineral Processing Department CSIR-Institute of Minerals and Materials TechnologyBhubaneswar 751013India R&D Centre National Mineral Development Corporation LimitedHyderabad 500028India

With gradually diminishing Fe grade in tandem with the ever-increasing demand for high-grade iron ores,iron ore industries are now focusing on the beneficiation of low-grade iron ore fines,mainly considered ***,the scarcity of water at many of the mines’sites and the new water conservation policies of the governments have necessitated research on suitable dry beneficiation *** this context,an effort has been made to evaluate the efficacy of a dry classification unit,such as the vsk separator,in upgrading the iron values of two low-grade Indian iron ore fines,named sample 1 and sample *** mineralogical studies,involving scanning electron microscopy and X-ray diffraction,suggest that sample 1 is a low-grade blue dust sample(51.2wt%Fe)containing hematite and quartz as the major minerals,while sample 2(53.3wt%Fe)shows the presence of goethite in addition to hematite and *** experiments,carried out using Box-Benkhen statistical design,indicate that blower speed,followed by feed rate,is the most influencing operating parameter in obtaining a good product in the vsk *** optimum levels of the operating factors,a fines product with~55wt%Fe at a yield of~40%can be obtained from sample 1,while sample 2 can be upgraded to~56wt%Fe at a yield of~85%.The results suggest that the vsk separator can be employed as an efficient intermediate unit operation in a processing circuit to upgrade the iron contents of iron ore fines.

关键词： iron ore fines dry beneficiation vsk separator Box–Behnken design

Main Directions and Recent Test Modeling Results of Lithium Capillary-Pore systems as Plasma Facing Components

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Plasma science and Technology 2004年第3期6卷 2291-2295页

作者： v.A.evtikhin I.e.Lyublinski A.v.vertkov e.A.Azizov s.v.Mirnov v.B.Lazarev s.M.sotnikov v.M.safronov A.s.Prokhorov v.M.korzhavin FsUe "Red star"-"Prana-Center" Co Moscow Russian FsUe TRINITI Troitsk Moscow region Russian Federation RF Ministry for Atomic energy Moscow

At present the most promising principal solution of the divertor problemappears to be the use of liquid metals and primarily of lithium Capillary-Pore systems (CPs) as ofplasma facing materials. A solid CPs filled with liquid lithium will have a high resistance tosurface and volume damage because of neutron radiation effects, melting, splashing and thermalstress-induced cracking in steady state and during plasma transitions to provide the normaloperation of divertor target plates and first-wall protecting elements. These materials will not bethe sources of impurities inducing an increase of Z_(eff) and they will not be collected as dust inthe divertor area and in ducts. experiments with lithium CPs under simulating conditions of plasmadisruption on a hydrogen plasma accelerator Mk-200 [~ (10 - 15) MJ/m^2, ~ 50 μs] have beenperformed. The formation of a shielding layer of lithium plasma and the high stability of thesesystems have been shown. The new lithium limiter tests on an up-graded T-11M tokamak (plasma currentup to 100 kA, pulse length ~0.3 s) have been performed. sorption and desorption of plasma-forminggas, lithium emission into discharge, lithium erosion, deposited power of the limiter areinvestigated in these experiments. The first results of experiments are presented.

关键词： lithium divertor plasma facing material

empirical pairing gaps and neutron-proton correlations

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Chinese Physics C 2019年第1期43卷 109-121页

作者： B.s.Ishkhanov s.v.sidorov T.Yu.Tretyakova e.v.vladimirova Faculty of Physics Lomonosov Moscow State University skobeltzyn Institute of Nuclear Physics Lomonosov Moscow State University

Analysis of various mass formulas related to neutron-proton correlations in atomic nuclei is carried *** the example of the N =Z chain it is shown that for self-adjoint nuclei various formulas proposed in literature for estimating the np pairing energy lead to similar results. significant differences between the calculation methods arise when nuclei with N = Z are considered, which allows to reveal the complexity of neutron-proton correlations in different types of atomic nuclei and to make assumptions on the correspondence of the mass relation to the real effect of np pairing. The shell Model parametrization of the binding energy makes it possible to draw additional conclusions on the structure of mass formulas and their relationship.

关键词： nucleon interaction models of atomic nuclei nucleon pairing in atomic nuclei

Adsorption and photo-catalytic properties of layered lepidocrocite-like quasi-amorphous compounds based on modified potassium polytitanates

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Particuology 2014年第6期12卷 22-28页

作者： e.v.Tretyachenko A.v.Gorokhovsky G.Y.Yurkov F.s.Fedorov M.A.vikulova D.s.kovaleva e.e.Orozaliev Department of Chemistry Saratov State Technical University

TiO2 compounds possess relatively high adsorption abilities and exhibit high photocatalytic activities that exhibit potential for the destruction of organic pollutants in natural and waste *** potassium polytitanates modified using transition metals and their oxides/hydroxides generate new nanomaterials that operate in the visible spectral *** study presents the synthesis and investigation of the structure,composition and photocatalytic activity of powdered nanoscale quasi-amorphous potassium polytitanates particles modified with iron,zinc,copper,cobalt and nickel sulfate in aqueous *** of the powders investigated in this work exhibit a high adsorption capacity for methylene blue dye（15-20mg/g） related to the welldeveloped surface of the layered potassium polytitanate *** transition metals and their oxides/hydroxides influences the electronic structure of the obtained systems.A high photocatalytic activity was observed for systems containing iron,zinc,nickel and their oxides/hydroxides in the ultraviolet and visible ranges.

关键词： Layered potassium titanate Chemical modification Heterostructured particles Photocatalytic activity Adsorption