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Dynamic failure of dry and fully saturated limestone samples based on incubation time concept

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 125-134页

作者： Yuri v. Petrov Ivan v. Smirnov Grigory A. volkov Andrei K. Abramian anatoliy M. Bragov Stanislav N. verichev Saint Petersburg University Universitetskaya nab. 7-9 Saint Petersburg 199034 Russia Institute of Problems of Mechanical Engineering Russian Academy of Sciences Bolshoj pr. 61 V.O. Saint Petersburg 199178 Russia Lobachevsky State University of Nizhni Novgorod Prospekt Gagarina 23 Nizhny Novgorod 603950 Russia Allseas Engineering B.v. Poortweg 12 Delft 2612 PA The Netherlands

This paper outlines the results of experimental study of the dynamic rock failure based on the comparison of dry and saturated limestone samples obtained during the dynamic compression and split tests. The tests were performed using the Kolsky method and its modifications for dynamic splitting. The mechanical data(e.g. strength, time and energy characteristics) of this material at high strain rates are obtained. It is shown that these characteristics are sensitive to the strain rate. A unified interpretation of these rate effects, based on the structuraletemporal approach, is hereby presented. It is demonstrated that the temporal dependence of the dynamic compressive and split tensile strengths of dry and saturated limestone samples can be predicted by the incubation time criterion. Previously discovered possibilities to optimize(minimize) the energy input for the failure process is discussed in connection with industrial rock failure processes. It is shown that the optimal energy input value associated with critical load, which is required to initialize failure in the rock media, strongly depends on the incubation time and the impact duration. The optimal load shapes, which minimize the momentum for a single failure impact, are demonstrated. Through this investigation, a possible approach to reduce the specific energy required for rock cutting by means of high-frequency vibrations is also discussed.

关键词： Dynamic strength Incubation time criterion Split Hopkinson pressure bar(SHPB) test Tensile strength Compressive strength Water-saturated limestone vibration-assisted rock cutting

Diatomic Gaseous Sulfur Obtained at Low Temperature Catalytic Decomposition of Hydrogen Sulfide

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Journal of Chemistry and Chemical Engineering 2013年第11期7卷 1007-1013页

作者： anatoliy N. Startsev Olga v. Kruglyakova Boreskov Institute of Catalysis Novosibirsk 630099 Russia

Experimental evidences of occurrence of gaseous diatomic sulfur produced in the low temperature catalytic decomposition of hydrogen sulfide 2 H2S ←→ 2 H2 ＋ S2 （g） are summarized. The S2 molecule is suggested to be in the ground triplet state. Analysis of literature data allows concluding that the S2 metastable singlet state is realized in the thermal dissociation of hydrogen sulfide and solid sulfur. Arguments in favor of the hypothesis are been discussed.

关键词： Diatomic gaseous sulfur H2S decomposition sulfur electronic structure reaction thermodynamics standard enthalpyformation.

Electrochemical top-down synthesis of C-supported Pt nanoparticles with controllable shape and size:Mechanistic insights and application

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Nano Research 2021年第8期14卷 2762-2769页

作者： Batyr Garlyyev Sebastian Watzele Johannes Fichtner Jan Michalicka Alexander Schokel anatoliy Senyshyn Andrea Perego Dingjie Pan Hany A.El-Sayed Jan M.Macak Plamen Atanassov Iryna v.Zenyuk Aliaksandr S.Bandarenka Physics of Energy Conversion and Storage Technical University of MunichJames Franck Strafle 185748 Garching Germany Central European Institute of Technology Brno University of TechnologyPurkynova 12361200 BrnoCzech Republic Deutsches Elektronen Synchrotron(DESY) Notkestr.8522607HamburgGermany Heinz Maier-Leibnitz-Zentrum(MLZ) Technische Universitat MiinchenLichtenbergstr.185748 Garching Germany Department of Chemical Engineering National Fuel Cell Research Center University of CaliforniaIrvine92697-2580 CaliforniaUSA Department of Material Science and Engineering University of CaliforniaIrvine92697-2580 CaliforniaUSA Chair of Technical Electrochemistry Technical University of MunichLichtenbergstrafie 485748 Garching Germany

In this work,we demonstrate the power of a simple top-down electrochemical erosion approach to obtain Pt nanoparticle with controlled shapes and sizes(in the range from-2 to-10 nm).Carbon supported nanoparticles with narrow size distributions have been synthesized by applying an alternating voltage to macroscopic bulk platinum structures,such as disks or *** using any surfactants,the size and shape of the particles can be changed by adjusting simple parameters such as the applied potential,frequency and electrolyte *** instance,application of a sinusoidal AC voltage with lower frequencies results in cubic nanoparticles;whereas higher frequencies lead to predominantly spherical *** the other hand,the amplitude of the,sinusoidal signal was found to affect the particle size;the lower the amplitude of the applied AC signal,the smaller the resulting particle ***/C catalysts prepared by this approach showed 0.76 A/mg mass activity towards the oxygen reduction reaction which is-2 times higher than the state-of-the-art commercial Pt/C catalyst(0.42 A/mg)from *** addition to this,we discussed the mechanistic insights about the nanoparticle formation pathways.

关键词： electrochemical synthesis platinum nanoparticles oxygen reduction reaction

Copper-induced liver fibrosis affects the behavior of bone marrow cells in primary culture

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Frontiers in Biology 2017年第4期12卷 271-279页

作者： anatoliy I. Bozhkov Eugeniy G. Ivanov Yuliya A. Kuznetsova Svetlana L. Ohiienko Anastasiya Yu. Bondar 1. Research Institute of Biology of v.N. Karazin Kharkov National University sq. Svobody 4 61022 Kharkov Ukraine

BACKGROUND： The present study investigated the effects （LMCC）, which were administered per os, on the differentiation, of rats in primary culture. of low-molecular-weight components of bovine colostrum growth, and survival of cells obtained from the bone marrow METHODS： Bone marrow cells （BMCs） were obtained from both the rat femurs and were cultured in medium 199 supplemented with antibiotics （8% streptomycin and 8% gentamycin） and 20% inactivated fetal calf serum. In addition, the number of BMCs was counted and their morphotypes were determined. RESULTS： Animals were treated with copper （Cu） sulfate to induce liver fibrosis. Subsequent treatment with LMCC eliminated growth inhibition and normalized the bodyweight and temperature of animals with Cu-induced liver fibrosis. The number of lymphocytes in the bone marrow of animals with Cu-induced liver fibrosis was significantly higher than that in the bone marrow of control animals. The number ofneutrophils in untreated animals with liver fibrosis and LMCC-treated animals with liver fibrosis was lower than that in control animals. Neutrophils obtained from untreated animals with liver fibrosis and LMCC-treated animals with liver fibrosis underwent two-times faster degradation in vitro than neutrophils obtained from control animals. CONCLUSIONS： Our results indicate that LMCC affects the distribution of different morphological types of BMCs but does not prevent their degradation in vitro, which was two-times faster than that of BMCs obtained from control animals.

关键词： bone marrow cells bone marrow colostntm liver fibrosis

Estimation of Mercury Intake from Consumption of Fish and Seafood in Russia

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Food and Nutrition Sciences 2016年第7期7卷 516-523页

作者： anatoliy v. Gorbunov Boris v. Ermolaev Sergey M. Lyapunov Olga I. Okina Sergey S. Pavlov Marina v. Frontasyeva Geological Institute Russian Academy of Sciences Moscow Russia Joint Institute for Nuclear Research Dubna Russia

Data on the mercury concentration in freshwater and marine fish and seafood on the territory of Russia are presented. The level and pattern of the fish and seafood consumption in various regions of Russia are found from the analysis of open statistics. Regions with the maximum and minimum consumption of fish products are established. Mercury intake from these products in a human organism is calculated. It is shown that at the current level and pattern of the diet in Russia fish cannot be a source of high mercury concentrations in a human organism.

关键词： Mercury Marine and Freshwater Fish Seafood Consumption Level Human Organism Intake

Efficacy of the new therapeutic approach in curing malignant neoplasms on the model of human glioblastoma

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Cancer Biology & Medicine 2021年第3期18卷 910-930页

作者： Evgeniya v.Dolgova Oleg M.Andrushkevich Polina E.Kisaretova Anastasia S.Proskurina Genrikh S.Ritter Tatyana D.Dubatolova Margarita v.Romanenko Oleg S.Taranov Yaroslav R.Efremov Evgeniy L.Zavyalov Alexandr v.Romaschenko Sergey v.Mishinov Svetlana S.Kirikovich Evgeniy v.Levites Ekaterina A.Potter Alexandr A.Ostanin Elena R.Chernykh Stanislav Yu.Roshchin anatoliy v.Bervitskiy Galina I.Moysak Jamil A.Rzaev Sergey S.Bogachev Institute of Cytology and Genetics SB RAS Novosibirsk 630090Russia A.I.Evdokimov Moscow State University of Medicine and Dentistry Moscow 127473Russia Institute of Molecular and Cellular Biology Novosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia The State Research Center of virology and Biotechnology"vector" KoltsovoNovosibirsk 630559Russia First Department of Neurosurgery Ya.L.Tsivian Novosibirsk Research Institute of Traumatology and OrthopaedicsNovosibirsk 630091Russia Institute of Fundamental and Clinical immunology Novosibirsk 630099Russia Sklifosovsky Research Institute of Emergency Medicine Moscow 129010Russia Federal Center of Neurosurgery Novosibirsk 630048Russia

Objective:Glioma is a highly invasive tumor,frequently disposed in essential areas of the brain,which makes its surgical excision extremely difficult;meanwhile adjuvant therapy remains quite ***:In the current report,a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma *** approach,termed"Karanahan",is aimed at the eradication of cancer stem cells(CSCs),which were recently shown to be capable of internalizing fragments of extracellular double-stranded *** being internalized,these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics,and such an interference results either in elimination of CSCs or in the loss of their tumorigenic *** of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA ***:U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient *** SCID mice with developed subcutaneous grafts,the treatment resulted in reliable slowing down of tumor growth rate(Pveloped graft and subsequent therapeutic treatment,the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the ***:The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.

关键词： Glioblastoma U87 cell line mytomycin C cancer stem cells TAMRA

Age and Geochemical Characteristics of Major Mafic Dyke Swarms in the Southern Part of the Siberian Craton

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 125-126页

作者： Tatiana v.DONSKAYA Dmitry P.GLADKOCHUB Richard E.ERNST Sergei A.PISAREvSKY anatoliy M.MAZUKABZOv Ulf SODERLUND Michael T.D.WINGATE Michael A.HAMILTON Elena I.DEMONTEROvA Institute of the Earth’s Crust Siberian Branch of the Russian Academy of Sciences Department of Earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University Australian Research Council Centre of Excellence for Core to Crust Fluid Systems(CCFS)and the Institute for Geoscience Research(TIGe R) Department of Applied GeologyCurtin University School of Earth and Environment University of Western Australia GeoB iosphere Science Centre Department of GeologyUniversity of Lund Geological Survey of Western Australia Department of Earth Sciences University of Toronto

Several generations of mafic dyke swarms of different ages and geochemical characteristics cut Precambrian rocks of the southern part of the Siberian craton(Irkutsk Promontory).Each generation of dykes is related to a

关键词： Age and Geochemical Characteristics of Major Mafic Dyke Swarms in the Southern Part of the Siberian Craton ppm

Development of Hydrogel Polyelectrolyte Membranes with Fixed Sulpho-Groups via Radical Copolymerization of Acrylic Monomers

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Materials Sciences and Applications 2011年第4期2卷 270-275页

作者： Ivan A. Stadniy viktoriia v. Konovalova Yuriy M. Samchenko Ganna A. Pobigay anatoliy F. Burban Zoya R. Ulberg 不详

Electrolyte hydrogels are perspective materials for applications in electrochemical devices, which work at ambient temperatures. In this work, hydrogel sulpho-modified membranes were formed by radical co-polymerization of sodium styrensulphonate and potassium sulphopropyl acrylate with acrylamide and acrylonitrile. The hydrogel membranes were obtained in the form of thin films. Properties of the membranes were studied by thermogravimetry, mass-spectrometry and IR-spectrometry. The prepared membranes were thermally stable up to 70°C - 90°C, and showed ion exchange capacity and swelling coefficients sufficient for use as ion-exchange or proton-conducting membranes.

关键词： Copolymer Hydrogels Polyelectrolyte Membranes Acrylamide Swelling Ion Exchange Capacity Thermogravimetry

Stationary Distribution of Random Motion with Delay in Reflecting Boundaries

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Applied Mathematics 2010年第1期1卷 24-28页

作者： anatoliy A. Pogorui Ramón M. Rodríguez-Dagnino Tecnológico de Monterrey (ITESM) Electrical and Computer Engineering. Sucursal de correos Monterrey México

In this paper we study a continuous time random walk in the line with two boundaries [a,b], a < b. The particle can move in any of two directions with different velocities v1 and v2. We consider a special type of boun... 详细信息

In this paper we study a continuous time random walk in the line with two boundaries [a,b], a ve in any of two directions with different velocities v1 and v2. We consider a special type of boundary which can trap the particle for a random time. We found closed-form expressions for the stationary distribution of the position of the particle not only for the alternating Markov process but also for a broad class of semi-Markov processes.

关键词： Random Motion Reflecting Boundaries Semi-Markov Random Walk