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Tailoring properties of reticulated vitreous carbon foams with tunable density

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Frontiers of Materials Science 2016年第2期10卷 157-167页

作者： Oleg SMORYGO Alexander MARUKOVICH Vitali MIKUTSKI Vassilis STATHOPOULOS Siarhei HRYHORYEU vladislav sadykov Powder Metallurgy Institute National Academy of Sciences of Belarus 41 Platonov Str. Minsk 220005 Belarus Technological Educational Institute of Sterea Ellada Psahna Evias 34400 Greece Belarusian National Technical University 65 Nezavisimosty Ave. Minsk 220013 Belarus Boreskov Institute of Catalysis Sibrian Branch of Russian Academy of Sciences 5 Lavrentiev Ave. 630090 Novosibirsk Russia Novosibirsk State University 2 Pirogova Str. 630009 Novosibirsk Russia

Reticulated vitreous carbon （RVC） foams were manufactured by multiple replications of a polyurethane foam template structure using ethanolic solutions of phenolic resin. The aims were to create an algorithm of fine tuning the precursor foam density and ensure an open-cell reticulated porous structure in a wide density range. The precursor foams were pyrolyzed in inert atmospheres at 700℃, 1100℃and 2000℃, and RVC foams with fully open cells and tunable bulk densities within 0.09-0.42 g/cm3 were synthesized. The foams were characterized in terms of porous structure, carbon lattice parameters, mechanical properties, thermal conductivity, electric conductivity, and corrosive resistance. The reported manufacturing approach is suitable for designing the foam microstructure, including the strut design with a graded microstructure.

关键词： foam vitreous carbon reticulated cellular structure pyrolysis

Modified Ceria-Zirconia Fluorite-Like Catalysts for the Combustion of Methane

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Journal of Natural Gas Chemistry 2006年第3期15卷 149-163页

作者： Tatiana Kuznetsova vladislav sadykov Lubsan Batuev Ella Moroz Elena Burgina Vladimir Rogov Vladimir Kriventsov Dmitrii Kochubey Boreskov Institute of Catalysis SB RAS Pr. Lavrentieva5Novosibirsk630090Russia

For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700 ℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities.

关键词： Ce-Zr-O Ca Mn Co Bi Nb structural features oxygen reactivity oxygen mobility methane combustion

Theoretical and experimental studies of gas preparation system for pressurization and reactive control system of launch vehicle

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Chinese Journal of Aeronautics 2024年第7期37卷 168-177页

作者： Valeriy TRUSHLYAKOV vladislav URBANSKY Vadim YUDINTSEV Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia

A new gas preparation system(GasPS-RCS)is proposed to solve two tasks:(A)to heat helium gas for tank pressurization;(B)to prepare gas for the Launch Vehicle(LV)Reactive Control System(RCS)at the LV orientation and stabilization sections of the LV on passive parts of the flight trajectory,to provide conditions for launching the Liquid Rocket Engine(LRE).The system includes a gas generator based on hydrogen peroxide,a separator for water separation,heat exchangers independent of the LRE,and gas-jet *** proposed new system allowed to reduce the length of pressurizing gas lines and reduce the increased helium gas consumption during the heat exchanger warm-up interval of the LRE during its launch.A special advantage of the proposed system is the possibility of ground testing of heat exchangers without an operating LRE.A mathematical model based on the first law of thermodynamics was used to perform a comparative analysis of GasPS-RCS with traditional pressurization and RCS *** validate the mathematical model,the experimental studies of helium pressurizing of a liquid nitrogen tank were *** results show that the deviation of experimental and calculated values for pressure is 1.1%and for temperature up to 2%.According to the results of comparative analysis,the GasPS-RCS is 259 kg lighter for the first stage and 80 kg lighter for the second stage of the LV.

关键词： Engine restart Reactive control system Tank pressurization Cryogenics Hydrogen peroxide Heat exchanger

Specific structural features of LnZrOx(Ln:La, Sm) mixed oxides prepared by different methods

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Progress in Natural Science:Materials International 2018年第4期28卷 437-446页

作者： Tatyana Kuznetsova Tamara Kriger Yurii Chesalov ANDrey Boronin Arcadii Ishchenko Pavlos K.PANDis Vladimir Krivensov Galina Litvak Tatyana Larina vladislav sadykov Vassilis N.Stathopoulos Boreskov Institute of Catalysis Novosibirsk State University Laboratory of Chemistry and Materials Technology Department of Electrical Engineering School of Technological Applications Technological Education Institute of Sterea Ellada

LnZrOx(Ln: La, Sm) mixed oxides of Ln: Zr = 1 were prepared by different methods(complex polymerized method, sorption of cations on starch from aqueous salt solution and conventional co-precipitation with additional redispersion of precipitate by ultra sound) and calcined at 700–1300 °C. Their specific structural features and changes were studied and discussed. Various characterization methods were used such as X-ray diffraction,Electron microscopy, Fourier-transform infrared and Raman spectroscopy, UV–Vis spectroscopy, X-Ray absorption fine structure and X-ray photoelectron *** formation of pyrochlore structure occurred at 1100–1300 °C from fluorite-like pseudocubic phase ZrO2regardless the method of preparation. This phase had a block-like structure consisting of ZrO2nanocrystals stabilized by Ln cations and residual anions such as hydroxyls and carbonates. The desorption of such anions with heating already started at 900 °C and lead to local changes of Zr cations coordination to octahedral and to the formation of pyrochlore nanodomains inclusions within fluorite-like phase. The increased cation mobility and further elimination of anions caused by further heating was accompanied by the formation of bulk pyrochlore phase at 1100–1300 °C. Even after calcination at 1300 °C the local microheterogeneity as well as defects were identified at domains boundaries or sintered microstructure. These specific features of the formed pyrochlores depend on the method of preparation.

关键词： Fluorites Pyrochlores Synthesis Powders Structure

Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1925-1939页

作者： Artur V.Dmitrenko vladislav M.Ovsyannikov Department of Physics National Research Nuclear University(MEPhI)Kashirskoye Shosse 31Moscow115409Russian Federation Department of Thermal Engineering and Department of Waterways Ports and Hydraulic StructuresRussian University of Transport(MIIT)Obraztsova Street 9Moscow127994Russian Federation

The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related *** equations contain derivatives of the first order with respect to *** derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to *** are used to derive the wave *** differential wave equation is second order in ***,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave *** is important for calculating the generation of sound waves and water hammer ***,the Euler continuity equation with finite time increments is of *** finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate *** is a new branch in *** and cubic invariants will be used in differential wave equations of the second and third order in time.

关键词： Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock turbulence

Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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Chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang Li Pan vladislav A.Tuskaev Svetlana Ch.Gagieva Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of Chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

Parasites of the liver:A global problem?

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World Journal of Gastroenterology 2024年第30期30卷 3554-3559页

作者： vladislav V Tsukanov Alexander V Vasyutin Julia L Tonkikh Clinical Department of the Digestive System Pathology of Adults and Children Federal Research Center“Krasnoyarsk Science Center”of the Siberian Branch of the Russian Academy of SciencesScientific Research Institute of Medical Problems of the NorthKrasnoyarsk 660022Russia

Parasitic liver diseases can be caused by trematodes,cestodes,nematodes,and *** pathology is significant because millions of people in different parts of the world have liver parasites,which can manifest themselves in the development of inflammation,liver cysts,cholecystitis,cholelithiasis,pancreatitis and liver cirrhosis that are often threatening their *** International Agency for Research on Cancer considers three species of trematodes,Schistosoma haematobium,Opisthorchis viverrini and Clonorchis sinensis,to be *** modern examination methods,in some cases including extensive screening of large populations,are required for diagnosing liver *** of parasitic liver diseases is differentiated and can involve a combination of surgical and therapeutic *** is no doubt that the clinical and epidemiological scale allows one to regard parasitic liver diseases as a global healthcare problem.

关键词： Liver Parasites Epidemiology Diagnosis Clinics Treatment Echinococcosis Opisthorchiasis Fascioliasis Schistosomiasis

Formation of Micro, Nano and Atomic-Level Structure of CoAIOICo-AI Cermets Prepared by Mechanical Alloying

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材料科学与工程（中英文A版） 2012年第2期2卷 121-136页

作者： Andrey Andreev Aleksey Salanov Serguei Tikhov Svetlana Cherepanova Vladimir Zaikovskii Vladimir Usoltsev vladislav sadykov Olga Lapina Boreskov Institute of Catalysis SB RAS 630090 pr. Lavrentieva 5 Novosibirsk Russian Federation

SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko L.V.Kalinovskaya A.A.Kampf R.R.sadykov V.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation