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50 Years experience of the *** electric welding institute in Field of electron Beam welding

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

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Investigation of residual stresses in welded joints of heat-resistant magnesium alloy ML10 after electrodynamic treatment

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Journal of Magnesium and Alloys 2016年第2期4卷 77-82页

作者： L.M.Lobanov N.A.Pashchin o.L.Mikhodui J.A.Khokhlova The e.o.paton electric welding institute of the nas of ukraine KyivUkraine

In repair of aircraft structures of magnesium alloy ML10,the argon arc non-consumable electrode welding is *** this case,the residual welding stresses occur in repairwelds,being one of the causes for reducing the service characteristics of the restored *** stresses arise as a result of ***-weld heat treatment is used to reduce the residual *** heat treatment,which occurs after welding,increases the cost of *** leads to the search for alternative methods to control the stressed state of welded joints,one of which is electrodynamic treatment,which reduces the level of residual stresses in repair welds,and as a consequence,the cost of the welding repair in restoring aircraft *** was found from the results of experiments carried out,that the electrodynamic treatment allows reduces the initial level of stresses in welded joints,reaching 120 MPa,to 30 MPa,and at definite geometric characteristics of the specimens forming the field of compressive stresses,the values ofwhich are equal to-50 *** is shown that the optimum distance between the zones of treatment,being 5 mm,provides the guaranteed covering the zones of electrodynamic effect and,as a consequence,the maximum efficiency of the electric dynamic treatment.

关键词： electrodynamic treatment(eDT) Magnesiumalloy weldingstresses Repairwelding Aircraftenginecasing

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A Novel Method for Linear Systems of Fractional ordinary Differential equations with Applications to Time-Fractional PDes

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Computer Modeling in engineering & Sciences 2024年第5期139卷 1583-1612页

作者： Sergiy Reutskiy Yuhui Zhang Jun Lu Ciren Pubu A.Pidhornyi institute of Mechanical engineering Problems of nas of ukraine Kharkiv61046Ukraine College of Mechanics and Materials Hohai UniversityNanjing211100China Nanjing Hydraulic Research institute Nanjing210029China Shigatse everest Urban Investment and Development Group Co Ltd.857000China

This paper presents an efficient numerical technique for solving multi-term linear systems of fractional ordinary differential equations(FoDes)which have been widely used in modeling various phenomena in engineering and *** approximate solution of the system is sought in the formof the finite series over the Müntz *** using the collocation procedure in the time interval,one gets the linear algebraic system for the coefficient of the expansion which can be easily solved numerically by a standard *** technique also serves as the basis for solving the time-fractional partial differential equations(PDes).The modified radial basis functions are used for spatial approximation of the *** collocation in the solution domain transforms the equation into a system of fractional ordinary differential equations similar to the one mentioned *** examples have verified the performance of the proposed novel technique with high accuracy and efficiency.

关键词： System of FoDes numerical solution Müntz polynomial basis time fractional PDe BSM collocation method

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Structure and Properties of Nanostructured Vacuum-Deposited Foils of Invar Fe–(35–38 wt%)Ni Alloys

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Journal of Materials Science & Technology 2015年第11期31卷 1079-1086页

作者： V.M.Nadutov A.I.Ustinov S.A.Demchenkov Ye.o.Svystunov V.S.Skorodzievski G.V.Kurdyumov institute for Metal Physics of National Academy of Sciences of ukraine e.o.paton electric welding institute of National Academy of Sciences of ukraine

The process of electron beam vacuum deposition of the Fe-（35-38 wt%）Ni alloys at substrate temperatures Ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size of characteristic microstructural elements （grains and subgrains）. It was shown that refinement of foil microstructural elements to nanoscale is accompanied by their microhardness increase up to 4-5 GPa. The change of the thermal expansion coefficient （TeC） of the nanostructured （NS） foil of the Fe-35.1Ni alloy within the temperature range from -50 to 150 ℃ has some deviation from that observed for cast Invar alloy of the same composition. It has been found that the main factors affecting the peculiarities of thermal expansion of the NS foil can be related to the presence of small fraction of BCC- phase in them, high level of crystalline lattice microstrains and inhomogeneous magnetic order in FCC- phase. It was shown that as a result of additional thermal treatment of NS foils their invar properties become similar to that observed for cast Invar alloy but mechanical properties remain on the same level.

关键词： Fe-Ni alloys electron beam physical vapor deposition (eBPVD) Nanostructured materials Hardness Thermal expansion Mossbauer spectroscopy

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Hybrid bimetallic cluster Zro2/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

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Tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang Igor V.Zatovsky Jun-Ming Cao Xing-Long Wu Faculty of Chemistry Northeast Normal University F.D.ovcharenko institute of Biocolloidal Chemistry NAS Ukraine Moe Key Laboratory for UV Light-emitting Materials and Technology Northeast Normal University

Acid hydrogen evolution reaction (HeR) is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage [1].Although the performance of noble metal platinum (Pt)-based catalysts in acidic HeR is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances [2].Therefore,it is urgent to design and manufacture acidic HeR catalysts with high reactivity,high stability,and low cost.

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Solid-State Diffusion Bonding of NbSS/Nb5Si3 Composite Using Ni/Al and Ti/Al Nanolayers

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Acta Metallurgica Sinica(english Letters) 2019年第9期32卷 1142-1150页

作者： Xin-Yu Ren Hai-Shui Ren Yong-Wang Kang Hua-Ping Xiong Chong Pei Bo Chen Yao-Yong Cheng A.I.Ustinov welding and Plastic Forming Division Beijing Institute of Aeronautical MaterialsBeijing 100095China Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China e.o.paton electric welding institute of nas of ukraine Kiev 03680Ukraine

Diffusion bonding of refractory Nb–Si-based alloy was performed with Ni/Al and Ti/Al nanolayers under the condition of 1473 K/30 MPa/60 *** NbSS/Nb5Si3 in situ composite with the nominal composition of Nb–22 Ti–16 Si–3 Cr–3 Al–2 Hf was used as the parent *** joint microstructures were examined by using a scanning electron microscope equipped with an X-ray energy dispersive *** test was conducted for the bonded joints at room *** the joint bonded with Ni/Al multilayer,element diffusion occurred between the base metal and the nanolayer,with the reaction products of AlNb2+Ni3 Al,NiAl and AlNi2 Ti *** average shear strength was 182 *** using Ti/Al multilayer,the interface mainly consisted of TiAl,(Ti,Nb)Al and(Ti,Nb)2 Al phases,and the corresponding joints exhibited an increased strength of 228 *** this case,the fracture mainly took place in the TiAl phase and presented a typical brittle characteristic.

关键词： Nbss/Nb5Si3 composite Diffusion bonding Nanolayer Shear strength

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Synergistic Co-doping effect of CNTs and PVP in Na_(4)MnCr(Po_(4))3 cathode as a strategy for improving the electrochemical performance of SIBs

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Chinese Chemical Letters 2024年第2期35卷 539-543页

作者： Ruoyu Chen Denys S.Butenko Shilin Li Xinyu Zhang Guangshe Li Igor V.Zatovsky Wei Han College of Physics State Key Laboratory of Inorganic Synthesis and Preparative ChemistryInternational Center of Future ScienceJilin UniversityChangchun 130012China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China F.D.ovcharenko institute of Biocolloidal Chemistry NAS UkraineKyiv 03142Ukraine

In order to solve the contradiction between the rapidly growing energy demand and the excessive exploitation of fossil fuels,it is urgent to research and develops more environmentally friendly and efficient energy storage ***,the development of high-performance cathode materials to enhance the energy density of SIB is currently one of the most important topics of scientific *** high-voltage and low-cost cathode material for SIBs,a composite of carbon-coated Na_(4)MnCr(Po_(4))_(3)(nasICoN-type),polyvinylpyrrolidone(PVP),and modified carbon nanotubes(CNTs)is prepared by sol-gel and freeze-drying *** to the high conductivity of CNTs,the conductivity of the composite is significantly improved,and its initial capacity is increased to 114 mAh/g at 0.5 C and 96 mAh/g at 5 C(Mn^(2+)/Mn^(4+)conversion for voltage windows 1.4-4.3 V).Moreover,the multi-electrons transfer of Cr^(3+)/Cr^(4+) and Mn^(2+)/Mn^(4+) can provide a high capacity of 165 mAh/g at 0.1 C and 102 mAh/g at 5 C in the high voltage window of 1.4-4.6 ***,PVP can effectively inhibit the Jahn-Teller effect caused by Mn ion,making the composite have more excellent high-rate performance and *** addition,GITT,eIS and CV curves were drawn to better reveal the excellent kinetic properties of Na_(4)MnCr(Po_(4))_(3)@C@PVP@CNT cathode,and the mechanism of its performance improvement is deeply studied and ***,the co-doping of CNTs and PVP is a simple way to high conductivity and fast charging of cathode materials for SIBs.

关键词： Sodium-ion batteries Na_(4)MnCr(Po_(4))_(3) Carbon nanotubes Polyvinylpyrrolidone Synergistic effect

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Investigation of WZ Sge-type Dwarf Nova ASASSN-19oc:optical Spectroscopy and Multicolor Light Curve Analysis

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Research in Astronomy and Astrophysics 2024年第8期24卷 20-31页

作者： Viktoriia Krushevska Sergey Shugarov Paolo ochner Yuliana Kuznyetsova Mykola Petrov Peter Kroll Astronomical institute of the Slovak Academy of Sciences Tatranska Lomnica05960 VysokéTatrySlovakia Main Astronomical observatory of nas of ukraine 27 Akademika Zabolotnoho St.03143 KyivUkraine INAF—osservatorio Astronomico di Padova Vicolo dell’Osservatorio 5I-35122 PadovaItaly Department of Physics and Astronomy University of PadovaVia F.Marzolo 8I-35131 PadovaItaly Max Planck Computing and Data Facility(MPCDF) Gießenbachstrasse 2D-85748 GarchingGermany Sonneberg observatory Sternwartestr.32D-96515 SonnebergGermany

In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June *** carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova *** of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late *** have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(MV=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in *** fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.

关键词： (stars)binaries(including multiple) close-(stars)novae-cataclysmic variables-stars dwarf novae

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Cretaceous crown male ant reveals the rise of modern lineages

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Zoological Research 2024年第5期45卷 983-989页

作者： Qiong Wu Alexander G.Radchenko Michael S.engel Xiao-Qin Li Hong-Ru Yang Xing-Ru Li Chung-Kun Shih Dong Ren Tai-Ping Gao College of Life Sciences Capital Normal UniversityBeijing 100048China I.I.Schmalhausen institute of Zoology NAS of UkraineKiev 01054Ukraine Division of Invertebrate Zoology American Museum of Natural HistoryNew York 10024-5192USA Facultad de Ciencias Biológicas Universidad Nacional Mayor de San MarcosLima 11-0058Perú Departamento de entomología Museo de Historia NaturalUniversidad Nacional Mayor de San MarcosLima 15072Perú Department of Chemistry Analytical and Testing CenterCapital Normal UniversityBeijing 100048China Department of Paleobiology National Museum of Natural HistorySmithsonian InstitutionWashington DC 20013-7012USA

Most described Mesozoic ants belong to stem groups that existed only during the Cretaceous ***,the earliest known crown ants were dated to the Turonian(Late Cretaceous,ca.94-90 million years ago(Ma))deposits found in the USA,Kazakhstan,and ***,the recent discovery of an alate male ant in Kachin amber from the earliest Cenomanian(ca.99 Ma),representing a new genus and species,Antiquiformica alata,revises the narrative on ant *** can be distinctly differentiated from all known male stem ants by its geniculate antennae with elongated scape,extending far beyond the occipital margin of the head and half the length of the funiculus,as well as its partly reduced forewing ***,the combination of a one-segmented waist with a well-developed node,elongated scape extending beyond the occipital margin,and reduced forewing venation,particularly the completely reduced m-cu and rs-m crossveins and absence of rm and mcu closed cells,firmly places the fossil within the extant subfamily *** transform infrared spectroscopy(FTIR)confirmed that the amber containing Antiquiformica alata originated from the Kachin mines in *** discovery significantly revises our understanding of the early evolution of *** presence of Antiquiformica in Cenomanian amber indicates that the subfamily Formicinae emerged at least by the start of the Late Cretaceous,with crown ants likely originating earlier during the earliest Cretaceous or possibly the Late Jurassic,although paleontological evidence is lacking to support the latter hypothesis.

关键词： Formicidae Formicinae Morphology Taxonomy Antiquiformica alata Paleontology Kachin amber

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Low-agglomerated yttria nanopowders via decomposition of sulfate-doped precursor with transient morphology

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Journal of Rare earths 2014年第4期32卷 320-325页

作者： R.P.Yavetskiy D.Yu.Kosyanov V.N.Baumer A.G.Doroshenko A.I.Fedorov N.A.Matveevskaya A.V.Tolmachev o.M.Vovk institute for Single Crystals of nas of ukraine State Scientific Institution"institute for Single Crystals"of nas of ukraine

The fabrication peculiarities of low-agglomerated yttria （Y2o3） nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied. It was determined that Y2（oH）5（No3）x（Co2）y（So4）z·nH2o （n=1-2） crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2o3 particles upon calcination. effect was con-nected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidi-zation and attainment of isolation that occurred atТ=1100 °С. Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2o3 nanopowders. Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree.

关键词： precursor transient morphology sulfate-ions yttria nanopowders particle size sinterability rare earths

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