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An overview of progress in mg-based hydrogen storage films

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Chinese Physics B 2019年第9期28卷 68-77页

作者： Lyu Jinzhe andrey m Lider Viktor N Kudiiarov Division for Experimental Physics School of Nuclear Science & Engineering National Research Tomsk Polytechnic University

mg-based hydrogen storage materials are considered to be one of the most promising solid-state hydrogen storage materials due to their large hydrogen storage capacity and low cost. However, slow hydrogen absorption/desorption rate and excessive hydrogen absorption/desorption temperature limit the application of mg-based hydrogen storage *** present paper reviews the advances in the research of mg-based hydrogen storage film in recent years, including the advantage of the film, the function theory of fabricating method and its functional theory, and the influencing factors in the technological process. The research status worldwide is introduced in detail. By comparing pure mg, Pd-caped mg, nonpalladium capped mg, and mg alloy hydrogen storage films, an ideal tendency for producing mg-based film is pointed out,for example, looking for a cheap metal element to replace the high-priced Pd, compositing mg film with other hydrogen storage alloy of catalytic elements, and so on.

关键词： mg-based hydrogen storage film Pd-caped mg film mg alloy film interlayer intermetallic cooperative effect

Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

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Friction 2018年第3期6卷 323-340页

作者： Nikolai L SAVCHENKO andrey V FILIPPOV Sergei yu TARASOV andrey I DmITRIEV Evgeny V SHILKO Aleksandr S GRIGORIEV Institute of Strength Physics and materials Science SB RAS National Research Tomsk Polytechnic University National Research Tomsk State University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. Simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词： zirconia transformation toughening low-temperature degradation friction acoustic emission numerical modeling movable cellular automata method

Variability of emission lines in the optical spectra of the Herbig Be binary system HD 200775

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Research in Astronomy and Astrophysics 2019年第3期19卷 31-34页

作者： Anastasia P.Bisyarina andrey m.Sobolev Stanislav yu.Gorda Anatoly S.miroshnichenko Astronomical Observatory of the Ural Federal University Department of Physics and Astronomy University of North Carolina at Greensboro main (Pulkovo) Astronomical Observatory of the Russian Academy of Sciences Fesenkov Astrophysical Institute

In our previous papers we have improved the value of the orbital period of the binary Herbig Be star HD 200775 and showed that the [O I] and Si II 6347 and 6371 ?A emission lines displayed variations which correlate with the orbital period. In this paper we provide evidences that other broad emission lines of metals in the spectra of HD 200775 also exhibit variability, which is probably related to the orbital cycle of the binary. Analysis was performed based on the high-resolution spectral data collected over a time span of 6 years at the Kourovka Astronomical Observatory of the Ural Federal University(Russia) and the Three College Observatory of the University of North Carolina at Greensboro(USA) as well as archival spectral data compiled since 1994. We report new data points in the radial velocity curve of the He I 5876 ?A line near the extremal values of the radial velocity.

关键词： techniques spectroscopic-stars variables T Tauri,Herbig Ae/Be-stars individual HD 200775

Catagenetic type of manganese ores:REE and isotope(δ^(13)C,δ^(18)O)geochemical features(on the example of the Usa deposit,Russia)

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Acta Geochimica 2024年第6期43卷 1133-1152页

作者： Vladimir N.Kuleshov andrey yu.Bychkov Irina yu.Nikolaeva maria E.Tarnopolskaia Geological Institute Russian Academy of SciencesPyzhevskii Per.7119017 MoscowRussia Lomonosov moscow State University Leninskie Gory1119899 MoscowRussia

Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were *** data on the composition of REE exhibit both the distinct negative(Ce/Ce*_(PAAS)1)cerium anomalies and the positive Eu-anomaly(Eu/Eu*_(PAAS)>1).Negative Eu-anomalies are not *** contents of mn,Fe,REE,and Ce-anomalies show a positive correlation with each ***-anomalies and the amount of manganese and REE in relation to the carbon isotope composition(δ^(13)C)show a negative relationship and indicate that oxidized carbon of organic matter played an important role in the concentration of manganese and REE in manganese *** chemical and isotope composition of examined rocks indicates on secondary formation of *** major phases and sources are distinguished in the ore-forming process characterized by diff erent chemical(REE and ore elements)and isotope composition:(i)highgrade manganese ores(with high contents of REE and light carbon isotope composition)and(ii)low-grade manganese ores(with low contents of REE and heavy carbon isotope composition).

关键词： manganese ore REE Isotope composition Catagenesis Cambrian Siberia

Rare earth elements(REE)and isotope composition(δ^(13)C andδ^(18)O)of manganese ores of Chiatura deposit(Georgia):features of ore formation and genesis

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Acta Geochimica 2023年第4期42卷 779-801页

作者： Vladimir N.Kuleshov andrey yu.Bychkov Irina yu.Nikolaeva maria E.Tarnopolskaya Geological Institute Russian Academy of SciencesPyzhevskii Per.7MoscowRussia 119017 Lomonosov moscow State University Leninskie Gory1MoscowRussia 119899

The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were *** of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(Eu/Eu*_(PAAS))*** oolitic manganese ores were formed in oxic shallow marine *** content and distribution of REEs(in particular Ce and Eu)in these ores are connected mainly with ferrous *** performed C-and O-isotope research in mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)*** negative cerium anomalies in the studied carbonate ores reflect the specific REE patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's *** deficiency of cerium in this zone remains debatable and requires further *** of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and *** absence of europium anomaly indicates about lack of hydrothermal solution input.

关键词： REE Cerium anomaly Carbon and oxygen isotope geochemistry Oxide and carbonate manganese ores Chiatura deposit

Decomposition of carbon dioxide hydrate in the samples of natural coal with different degrees of metamorphism

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Chinese Journal of Chemical Engineering 2020年第2期28卷 492-501页

作者： Vyacheslav G. Smirnov Valeriy V. Dyrdin andrey yu. manakov Zinfer R. Ismagilov Kuzbass State Technical University Vesennaya str.28Kemerovo 650000Russian Federation Nikolaev Institute of Inorganic Chemistry SB RAS Ac.Lavrentiev ave.3Novosibirsk 630090Russian Federation Novosibirsk State University Pirogov Str.2Novosibirsk 630090Russian Federation Institute of Coal Chemistry and material Science SB RAS Sovetsky ave.18Kemerovo 650000Russian Federation

methane and carbon dioxide hydrates are one of the possible forms in which these gases exist in natural coal(for more detailed discussion see Refs [1,2]). In this work, the decomposition of carbon dioxide hydrate in five samples of natural coal differing from each other in metamorphism degree was investigated experimentally. Carbon dioxide hydrate dispersed in coals was synthesized from water adsorbed in these coals. During a linear temperature rise in an autoclave with the coal + hydrate sample the hydrate decomposition manifests itself as a step of increase in gas pressure, accompanied by a decrease/stabilization of the temperature of coal sample. The dependencies of the amount of hydrate formed on initial coal humidity and on gas pressure during hydrate formation were studied. It was demonstrated that each coal sample is characterized by its own humidity threshold below which hydrate formation in natural coal is impossible. With an increase in gas pressure, the amount of water transformed into hydrate increases. For the studied coal samples, the decomposition of carbon dioxide hydrates proceeds within a definite temperature and pressure range, and this range is close to the curve of phase equilibrium for bulk hydrate.

关键词： Gas hydrate Carbon dioxide Coal Coal rank Phase transformation Coal bed gas

Regularities in the E. coli promoters composition in connection with the DNA strands interaction and promoter activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第12期7卷 969-973页

作者： BEREZHNOY andrey yu SHCKORBATOV yuriy G. HISANORI Kiryu National Scientific Center Kharkov Physical-Technical Institute Kharkov 61108 Ukraine Institute of Biology Kharkov National University Maidan Svobody 4 Kharkov 61077 Ukraine Computational Biology Research Center National Institute of Advanced Industrial Science and Technology Koto-ku Tokyo 135-0064 Japan)

The energy of interaction between DNA strands in promoters is of great functional importance. Visualization of the energy of DNA strands distribution in promoter sequences was achieved. The separation of promoters in groups by their energetic properties enables evaluation of the dependence of promoter strength on the energetic properties. The analysis of groups (clusters) of promoters distributed by the energy of DNA strands interaction in ?55, ?35, ?10 and +6 sequences indicates their connection with the transcriptional activity.

关键词： DNA sequence Promoter strength DNA chains interaction energy DNA sequences classification

Gas-phase hydrogenation influence on defect behavior in titanium-based hydrogen-storage material

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Progress in Natural Science:materials International 2017年第1期27卷 105-111页

作者： Roman S.Laptev Viktor N.Kudiiarov yuri S.Bordulev andrey A.mikhaylov andrey m.Lider Department of General Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising materials for hydrogen storage. However, hydrogen penetration accompanies the exploitation of hydrogen storage alloys. In particular, hydrogen penetration and accumulation in titanium alloys changes their mechanical properties. Therefore, the research works of such materials are mainly focused on improving the reversibility of hydrogen absorption-liberation processes, increasing the thermodynamic characteristics of the alloys, and augmenting their hydrogen storage capacity. In the process of hydrogenation-dehydrogenation, the formed defects both significantly reduce hydrogen storage capacity and can also be used to create effective traps for hydrogen. Therefore, the investigation of hydrogen interaction with structural defects in titanium and its alloys is very important. The present work, the hydrogen-induced formation of defects in the alloys of commercially pure titanium under temperature gas-phase hydrogenation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding intensities If, Idand relative changes of parameters S/S0and W/W0, the peculiarities of hydrogen interaction with titanium lattice defects were investigated in a wide range of hydrogen concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrogen Lattice defects Positron annihilation Positron lifetime Doppler broadening

Substituted diamides of dipicolinic acid as extractants and ionophores for rare earth metals

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Journal of Rare Earths 2023年第8期41卷 1234-1241,I0005页

作者： Yingchao Ren Valery A.Polukeev Ekaterina V.Kenf Liudmila I.Tkachenko mikhail yu Alyapyshev Vasily A.Babain andrey V.Nechaev andrey V.Legin Dmitry O.Kirsanov Institute of Chemistry Saint-Petersburg UniversityPeterhofUniversitetsky Prospect 26198504Saint-PetersburgRussia JSVC Vekton Ul.2-oy Luch 9192019Saint-PetersburgRussia Khlopin Radium Institute 194021282nd Murinsky avRussia ThreeArc mining LLC Pr.Narodnogo Opolchenia 10198216Saint-PetersburgRussia Rusredmet Vosstanovleniya str.15bl.3198320St.PeterburgKrasnoe seloRussia

The variety of newly synthesized diamides of dipicolinic acid(DPA)bearing methyl-and oxymethyl substituents in various positions of phenyl ring was investigated as potential ligands for liquid-liquid extraction of rare earth metal ions and as membrane active compounds in plasticized polymeric membranes of potentiometric *** is found that scandium is extracted with 2,6-pyridinedicarboxylic acid diamides similarly to heavy lanthanides,while yttrium is extracted together with light group *** shows high selectivity for the separation of cadmium/zinc,lead/nickel or copper/nickel *** four out of six studied ligands demonstrate significant potentiometric sensitivity towards scandium,yttrium and lanthanides in 10^(-7)-10^(-3)mol/L concentration range in nitric acid *** trends in sensitivity values vary depending on a ligand structure and the highest values are observed for Sc^(3+)and heavy *** to the evaluated selectivity Sm^(3+)is the most preferred ion,while La^(3+)is the most *** differences in sensor behavior in rare earth metal solutions assume that such devices can be applied in sensor arrays for potentiometric analysis of lanthanide mixtures.

关键词： Dipicolini cacid diamides Scandium Yttrium Lanthanides Extraction Potentiometric sensors