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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

Novel materials for solid oxide fuel cells cathodes and oxygen separation membranes:Fundamentals of oxygen transport and performance

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Carbon Resources Conversion 2020年第1期3卷 112-121页

作者： vladislav a.sadykov Ekaterina M.Sadovskaya Nikita F.Eremeev Elena Yu.Pikalova Nina M.Bogdanovich Elena A.Filonova Tamara A.Krieger Yulia E.Fedorova Alexey V.Krasnov Pavel I.Skriabin Anton I.Lukashevich Robert Steinberger-Wilckens Izaak C.Vinke Federal Research Center Boreskov Institute of Catalysis SB RAS 630090 NovosibirskRussia Novosibirsk State University 630090 NovosibirskRussia Institute of High Temperature Electrochemistry UB RAS 620137 YekaterinburgRussia Ural Federal University 620002 YekaterinburgRussia University of Birmingham EdgbastonBirmingham B152TTUK Forschungszentrum Jülich GmbH 52425 JülichGermany

In the field of modern hydrogen energy,obtaining pure hydrogen and syngas and then being able to use them for green energy production are significant *** solid oxide fuel cells(SOFC)and catalytic membranes for oxygen separation as well as materials for these devices is one of the most likely ways to solve these *** this work,the authors’recent studies in this field are reviewed;the fundamentals of developing materials for SOFC cathodes and oxygen separation membranes’permselective layers based on research of their oxygen mobility and surface reactivity are ***-Popper phases Ln_(2-x)Ca_(x)NiO_(4+δ)(LnCNO)and perovskite-fluorite nanocomposites PrNi_(0.5)Co_(0.5)O_(3-δ)-Ce_(0.9)Y_(0.1)O_(2-δ)(PNC-YDC)were studied by isotope exchange of oxygen with C_(18)O_(2)and^(18)O_(2)in flow and closed *** LnCNO a high oxygen mobility was shown(D*~10^(-7)cm^(2)/s at 700℃),being provided by the cooperative mechanism of oxygen migration involving both regular and highly-mobile interstitial *** PNC-YDC dominated a wide fast diffusion channel via fluorite phase and interphases due to features of the redistribution of cations resulting in superior oxygen mobility(D*~10^(-8)cm^(2)/s at 700℃).After optimization of composition and nanodomain structure of these materials,as cathodes of SOFC they provided a high power density,while for asymmetric supported oxygen separation membranes-a high oxygen permeability.

关键词： Solid oxide fuel cells Oxygen separation membranes Oxygen mobility Perovskites Nanocomposites Ruddlesden-Popper phases

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

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

Change in Grain-Size Composition of Lignite under Cyclic Freezing-Thawing and Wetting-Drying

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Natural Resources 2024年第1期15卷 17-27页

作者： Natalia S. Batugina vladislav I. Fedorov Chersky Institute of Mining of the North Siberian Branch Russian Academy of Sciences Yakutsk Russia

The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.

关键词： Lignite Freezing-Thawing Cycle Wetting-Drying Cycle Grain Size Composition Dust Coal Storage Loss Quality

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryavtsev Yulia V.Sotnikova vladislav A.Stolyarov Timur V.Mufakharov Valery V.Vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov Yulia V.Cherepkova Special Astrophysical Observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

非洲最恐怖的生命禁区一百年里无人敢涉足的达洛尔

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环球人文地理 2024年第5期 96-103页

作者：李理 vladislav Radek Benot ArtushFoto Lina dinozzaver Michail mikhail cheremkin flickr

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报...

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报告中，就已没有此地区的人口数据。这里是世界上最遥远、最荒芜的地区之一，没有学校、没有商店，也没有公路，对外交通除了游客车队，就只有前往该地收集盐块的阿法尔人与骆驼。然而，这里的形势极不稳定，

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