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50 Years Experience of the *** Electric Welding Institute in Field of Electron Beam Welding

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稀有金属材料与工程 2011年第S4期40卷 6-13页

作者： O.K.Nazarenko v.m.Nesterenkov E.O.Paton Electric Welding Institute of the NAS of Ukraine

Studying the possibilities of electron beam welding (EBW) and the principles of construction of equipment for electron beam welding,led by academician Boris Evgenyevich Paton,began at the *** Electric Welding Institute (PWI) in *** resulted in development of the first laboratory-scale plant and welding of different small *** year later the method of electron beam welding turned out to be in great demand:in nuclear power engineering,in production of electric vacuum devices and liquid-fuel rocket *** 1961-1962 owing to effective coordination of work performed at government level,the first production machines for electron beam welding were put into operation at a number of branch *** the next few years,application of electron beam welding became wider,first of all in the above mentioned industries,and simultaneously electron beam welding began to be accepted by aircraft and power engineering *** 1960-s PWI organized in Ukraine full-scale production of power units,developed by it (guns,power sources and control systems) on the basis of Sumy Factory of Electron microscopes.72 complete sets of power source units of SP-30 type (25 kv,500 mА),330 complete sets of U-250А (30 kv,450 mА),320 complete sets of ELA-60 (60 kv,250,500 and 1000 mА) and ELA-120 (120 kv,1000 mА) were manufactured in different periods of *** October 16th 1969 the first test of electron beam welding and cutting of metals was carried out in ?Soyuz-6? spaceship,that practically initiated the space *** was performed in vulkan unit developed by *** that in space X-radiation and difficulties with high-voltage insulation could eliminate the possibility of electron beam application,low accelerating voltage (not higher than 8 kv) was used.

关键词： electron beam welding Paton Electric Welding Institute technology equipment material engineering

Interactive effects of metal pollution and ocean acidification on physiology of marine organisms

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Current Zoology 2015年第4期61卷 653-668页

作者： Anna v. Ivanina Inna m. Sokolova Department of Biological Sciences University of North Carolina at Charlotte Charlotte NC 28223 USA

Changes in the global environment such as ocean acidification （OA） may interact with anthropogenic pollutants including trace metals threatening the integrity of marine ecosystems. We analyze recent studies on the interactive effects of OA and trace metals on marine organisms with a focus on the physiological basis of these interactions. Our analysis shows that the responses to elevated CO2 and metals are strongly dependent on the species, developmental stage, metal biochemistry and the degree of environmental hypercapnia, and cannot be directly predicted from the CO2-induced changes in metal solubility and speciation. The key physiological functions affected by both the OA and trace metal exposures involve acid-base regulation, pro- tein turnover and mitochondrial bioenergetics, reflecting the sensitivity of the underlying molecular and cellular pathways to CO2 and metals. Physiological interactions between elevated CO2 and metals may impact the organisms＇ capacity to maintain ac- id-base homeostasis and reduce the amount of energy available for fitness-related functions such as growth, development and re- production thereby affecting survival and performance of estuarine populations. Environmental hypercapnia may also affect the marine food webs by altering predator-prey interactions and the trophic transfer of metals in the food chain. However, our under- standing of the degree to which these effects can impact the function and integrity of marine ecosystems is limited due the scar- city of the published research and its bias towards certain taxonomic groups. Future research priorities should include studies of metal x Pco2 interactions focusing on critical physiological functions （including acid-base, protein and energy homeostasis） in a greater range of ecologically and economically important marine species, as well as including the field populations naturally ex- posed （and potentially adapted） to different levels of metals and CO2 in their environments [Curre

关键词： CO2 Trace metals metal accumulation Acid-base homeostasis Bioenergetics Estuaries

Studies on Physical Chemistry of Rubber-Rice Husk Ash Composites

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Journal of Renewable materials 2019年第2期7卷 171-192页

作者： v.Subrahmanian m.Albert Noble Einstien Department of Rubber and Plastics Technology Anna UniversityMIT CampusChrompetINDIA 60044 master of Technology Rubber and Plastics DepartmentAnna UniversityMIT Campus

Nowadays an alternate source of filler from renewable and plant derivatives are being thought of in rubber industries due to their reliability,environmental and economic *** Husk Ash(RHA)a byproduct of the rice milling industry is obtained on partial and as well as full combustion of the rice *** ash is a good source of silica,silicates and needle shaped carbon and hence can be used as filler for *** the present study,a detailed investigation was carried out to understand the RHA as reinforcing material using mechanical properties and fractography using *** rubbers studied were natural rubber(NR),poly chloroprene(CR)and ethylene propylene diene monomer(EPDm).Interestingly,the RHA added NR stock on open mill mixing generated considerable amount of static *** properties of NR were found to be as good as regular *** compounds behaved well during *** the properties were found to be ***-RHA compounds were found to result in higher viscosity and the properties were not as *** SEm studies showed surprisingly cohesive failure as evidenced with the presence of flow lines and the fibrous filler(RHA)remains embedded in the matrix regardless of the chemistry of the repeating unit,NR,EPDm and the chlorine containing monomer inCR.

关键词： Rice husk ash rubber composites natural rubber polychloroprene rubber EPDm mooney Scorch SEm fractography

GIS-based cost distribution analysis of new consumer connections to an urban power grid

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Geo-Spatial Information Science 2015年第4期18卷 183-192页

作者： Sergey v.KOSYAKOv Artur m.SADYKOv Department of Software Engineering Ivanovo State Power Engineering UniversityIvanovoRussia Department of Geographical Information Systems Ivanovo State Power Engineering UniversityIvanovoRussia

In this paper,we propose a method of cost distribution analysis of new consumer connections to a city power grid by accounting for spatial restrictions and characteristics of existing *** practice,the calculation of connection costs for each new consumer includes the network design and financial *** suggest that connection costs should be calculated for the whole city based on the normative parameters at the stage when the object location is selected by investors and when power grid development is planned by power *** proposed method enables the modeling of new power line connection routes from every parcel of city land to possible points of connection to the operating networks based on the raster design of the *** optimal path is chosen by one criterion consisting of two components:the costs of both laying new power lines and providing sufficient power reserve in the chosen network connection *** as a computer program,the method has been used to calculate the costs of connections to low-voltage power lines.

关键词： GIS least-cost path analysis grid-connections urban power grid

Experimental nuclear charge density and theoretical description of theabove-barrier light heavy-ion fusion process

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Chinese Physics C 2023年第8期47卷 64-74页

作者： I.I.Gontchar m.v.Chushnyakova Physics and Chemistry Department Omsk State Transport UniversityOmskRussia Physics Department Omsk State Technical UniversityOmskRussia

Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus *** of the advanced methods for constructing this potential is the semi-microscopical double-folding model with m3 YParis *** and neutron densities are significant components of this *** correct nucleon density(ND) must reproduce the experimental nuclear charge density(NCD).However,those who deal with modeling the fusion process typically disregard this *** aim to achieve a good description of both the nuclear charge density and above-barrier fusion cross sections of even-even light nuclei with Z=*** consider several versions of NDs available in literature and construct our own approximation for the ND of the even-even spherical nuclei^(12)C,^(16)O,and^(40)Ca,abbreviated as FE-density(Fermi+exponential).We carefully compare the NCDs resulting from different versions of NDs with the experimental *** finding the nucleus-nucleus potential using the double-folding model with the density dependent m3 Y-Paris NN-forces and FE densities,we evaluate the abovebarrier fusion cross sections for five reactions,^(12)C+^(12)C,^(12)C+^(16)O,^(16)O+^(16)O,^(16)O+^(40)Ca,and^(40)Ca+^(40)Ca,and40Ca+40Ca,for which experimental data are *** cross sections are calculated using two approaches:a) the barrier penetration model and b) the trajectory model with surface friction(Tm).To find the transmission coefficients for the Tm,the Langevin equations are *** all considered reactions,our Tm typically reproduces the above-barrier experimental cross sections within 10-15%.The only adjustable parameter of the model,the optimal friction strength KRm,is found to be approximately 90 zs·Gev-1for the light reactions12C+12C,12C+16O,and16O+16O and approximately 15zs·Gev-1for the heavy reactions16O+40Ca and40Ca+*** latter findings are in reasonable agreement with the systematics found ***,the FE-recipe allows highly accurate and s

关键词： nuclear charge densities nucleon densities heavy-ion fusion surface friction double-fold-ing model

mean-Square Approximation of Navier-Stokes Equations with Additive Noise in vorticity-velocity Formulation

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Numerical mathematics(Theory,methods and Applications) 2021年第1期14卷 1-30页

作者： G.N.milstein m.v.Tretyakov Ural Federal University EkaterinburgRussia School of mathematical Sciences University of NottinghamNottinghamUK

We consider a time discretization of incompressible Navier-Stokes equations with spatial periodic boundary conditions and additive noise in the vorticity-velocity *** approximation is based on freezing the velocity on time subintervals resulting in a linear stochastic parabolic equation for *** each time step,the velocity is expressed via vorticity using a formula corresponding to the Biot-Savart-type *** prove the first mean-square convergence order of the vorticity approximation.

关键词： Navier-Stokes equations vorticity numerical method stochastic partial differential equations mean-square convergence

Instability of equilibrium of nonholonomic systems with dissipation and circulatory forces

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Applied mathematics and mechanics(English Edition) 2011年第2期32卷 211-222页

作者： m.vESKOvI v.OvI A.OBRADOvI Faculty of mechanical Engineering University of Kragujevac Faculty of mechanical Engineering University of Belgrade

The paper discusses the equilibrium instability problem of the scleronomic nonholonomic systems acted upon by dissipative, conservative, and circulatory forces. The method is based on the existence of solutions to the differential equations of the motion which asymptotically tends to the equilibrium state of the system as t tends to negative infinity. It is assumed that the kinetic energy, the Rayleigh dissipation function, and the positional forces in the neighborhood of the equilibrium position are infinitely differentiable functions. The results obtained here are partially generalized the results obtained by Kozlov et al. （Kozlov, v. v. The asymptotic motions of systems with dissi- pation. Journal of Applied mathematics and mechanics, 58（5）, 787-792 （1994）. merkin, D. R. Introduction to the Theory of the Stability of motion （in Russian）, Nauka, moscow （1987）. Thomson, W. and Tait, P. Treatise on Natural Philosophy, Part I, Cambridge University Press, Cambridge （1879））. The results are illustrated by an example.

关键词： nonholonomic constraint instability potential dissipative force

microstructure and mechanical properties of friction welded carbon steel(EN24) and nickel-based superalloy(IN718)

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International Journal of minerals,metallurgy and materials 2021年第1期28卷 111-119页

作者： v.T.Gaikwad m.K.mishra v.D.Hiwarkar R.K.P.Singh Kalyani Centre for Technology and Innovation Bharat Forge LimitedPune 411036India Department of materials Engineering Defense Institute of Advance TechnologyPune 411025India

Continuous-drive rotary friction welding was performed to join cylindrical specimens of carbon steel(EN24) and nickel-based superalloy(IN718), and the microstructures of three distinct weld zones—the weld interface(WI)/thermo-mechanically affected zone(TmAZ),the heat-affected zone(HAZ), and the base metal—were *** joint was observed to be free of defects but featured uneven flash *** backscatter diffraction(EBSD) analysis showed substantial changes in high-angle grain boundaries, low-angle grain boundaries, and twin boundaries in the TmAZ and ***, significant refinement in grain size(2 –5 μm) was observed at the WI/TmAZ with reference to the base *** possible causes of these are *** microhardness profile across the welded joint shows variation in *** changes in hardness are ascribed to grain refinement, phase transformation, and the dissolution of strengthening *** tensile test results reveal that a joint efficiency of 100% can be achieved using this method.

关键词： friction welding dissimilar metals EN24 IN718 microstructure mechanical properties

Coating of bioactive glass on magnesium alloys to improve its degradation behavior: Interfacial aspects

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Journal of magnesium and Alloys 2020年第4期8卷 999-1015页

作者： v.S.Yadav m.R.Sankar L.m.Pandey centre for the environment indian institute of technology guwahatiassam781039india department of mechanical engineering indian institute of technology guwahatiassam781039india department of mechanical engineering indian institute of technology tirupatiandhra pradesh517506india department of biosciences and bioengineering indian institute of technology guwahatiassam781039india

The preferable mechanical properties of mg alloys along with excellent compatibility with human bone have established their applicability as implant ***,a higher corrosion/degradation rate of mg alloys in body fluids limits its biomedical *** this direction,surface modification and coating are explored as appropriate strategies to mode the degradation rate of mg *** constituents of bioactive glass(BG)provide strength,bio-inertness and bone bonding ***,researchers have explored the coating of BG on mg alloys and investigated chemical,mechanical and biological properties of the coated *** this review,we have made an attempt to compile the literature works done on the coating of BG on mg alloys and its *** interfacial aspects of the coated substrates towards the degradation behavior are *** way forward to further improve the coating characteristics of BG coated mg alloys are remarked.

关键词： Bioactive glass magnesium alloys Adhesion strength Coating thickness Wettability Degradation