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The Promotional Role of Liquid Metal for Zeolite Catalysis

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The Promotional Role of Liquid Metal for Zeolite Catalysis

Biogeochemical conversion of sulfur species in saline lakes of Steppe Altai

第4届分子科学博士后学术年会

作者：周勇 Changqing Sun Biao Wang Andrei Y.Khodakov vitaly v.ordomsk. 东莞理工学院交叉科学研究中心与材料科学与工程学院

Zeolites find broad applications in the petrochemical, coal chemical, and daily chemical industries [1].The ongoing demand for sustainable fuel and chemical production stimulates innovation in zeolite catalytic systems, albeit with challenges. We have developed a liquid metal-assisted zeolite catalyst system and demonstrated that liquid metals significantly enhance the catalytic activity, selectivity, and stability of zeolites in both gas-phase [2] and liquid-phase [3] reactions. It suggests that liquid metals function by eliminating coke-forming compounds and optimizing the acidity of zeolites, thereby improving catalytic performance. Utilizing liquid metal as a promoter offers new opportunities for designing and fabricating efficient zeolite catalyst systems for diverse catalytic reactions.

关键词： Zeolite catalysts Liquid metal Catalysis Promotion effects

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Journal of Oceanology and Limnology 2018年第3期36卷 676-686页

作者： BORZENKO Svetlana v. KOLPAKOvA Marina N. SHvARTSEv Stepan L. ISUPOv vitaly P. Institute of Natural Resources Ecology and CryologySiberian Branch of Russian Academy of SeiencesChita 672049Russia Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia National Research Tomsk Polytechnic University Tomsk 634050Russia Tomsk Department of the Trofimuk Institute of Petroleum-Gas Geology and Geophysics Siberian Branch of the Russian Academy of SciencesTomsk 634050Russia Institute of Solid State Chemistry and Mechanochemistry Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia

The aim of the present research is to identify the main mechanisms of sulfur behavior in saline lakes in the course of time and followed transformations in their chemical composition. The influence of water on chemical composition of biochemical processes involved in decomposition of organic matter was determined by the study of behavior of reduced forms of sulfur in lakes. The determination of reduced forms of sulfur was carried out by successive transfer of each form of sulfur to hydrogen sulfide followed by photometric measurements. The other chemical components were determined by standard methods(atomic absorption, potentiometric method, titration method and others). The salt lakes of the Altai steppe were studied in summer season 2013–2015. Analysis of the chemical composition of the saline lakes of Altai Krai has shown that carbonate-, hydrocarbonate-and chloride ions dominate among anions; sodium is main cation; sulfates are found in subordinate amounts. Reduced forms of sulfur occur everywhere: hydrogen and hydrosulfide sulfur S^(2-) prevail in the bottom sediments; its derivative—elemental S^0—prevails in the lakes water. The second important species in water of soda lakes is hydrosulfide sulfur S^(2-), and in chloride lakes is thiosulfate sulfur S_2O_2^(3ˉ). The lag in the accumulation of sulfates in soda lakes in comparison to chloride lakes can be explained by their bacterial reduction, followed by the formation and deposition of iron sulfides in sediments. In chloride lakes gypsum is a predominantly barrier for sulfates.

关键词： saline lake sulfate reduction gypsum Altai

GSC 4560–02157: a new long-period eclipsing cataclysmic variable star

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Research in Astronomy and Astrophysics 2015年第7期15卷 1005-1011页

作者： Anton v.Khruslov Anatoly v.Kusakin Elena A.Barsukova vitaly P.Goranskij Azamat F.valeev Nikolay N.Samus Institute of Astronomy Russian Academy of Sciences Fesenkov Astrophysical Institute Special Astrophysical Observatory Russian Academy of Sciences Sternberg Astronomical Institute Lomonosov Moscow State University

We study the newly discovered variable star GSC 4560-02157. CCD photometry was performed in 2013-2014 at the Tien Shan Astronomical Observatory,and a spectrum was obtained with the 6-m telescope of the Special Astrophysical Observatory in June, 2014. GSC 4560-02157 is demonstrated to be an eclipsing variable star（P = 0.265359d）. All its flat-bottom primary minima are approximately at the same brightness level, but the star＇s out-of-eclipse brightness and brightness at secondary minima vary considerably（by up to 0.6m） from cycle to cycle. Moreover,there are short-term（time scale of 0.03-0.04 days） small-amplitude brightness variations out of eclipse. This behavior suggests a cataclysmic nature for the star, which is confirmed with a spectrum taken on 2014 June 5. The spectrum shows numerous emissions of the hydrogen Balmer series, He Ⅰ and He Ⅱ.

关键词： stars: dwarf novae -- binaries: eclipsing -- stars: individual: GSC 4560-02157

Thienopyrazine or Dithiadiazatrindene Containing Low Band Gap Conjugated Polymers for Polymer Solar Cells

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Chinese Journal of Polymer Science 2014年第7期32卷 844-853页

作者： Mukhamed L.Keshtov Dmitry v.Marochkin Ying-ying Fu Zhi-yuan Xie 耿延候 vitaly S.Kochurov Alexei R.Khokhlov A.N.Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Lomonosov Moscow State University Faculty of Physics 119991

Four new low-band-gap alternating copolymers （P-1, P-2, P-3 and P-4） based on electron-rich benzodithiophene and newly developed electron-deficient units, thienopyrazine or dithiadiazatrindene derivatives, were synthesized by Stille polycondensation. All polymers exhibit good solubility in common organic solvents and a broad absorption band in the visible to near-infrared regions. The film optical band gaps of the polymers are in the range of 1.28-2.07 ev and the highest occupied molecular orbital （HOMO） energy levels are in the range of-4.99 ev to -5.28 ev. Bulk heterojunction polymer solar cells （PSCs） of the polymers were fabricated with phenyl-C61-butyric acid methyl ester （PC61BM） as acceptor material, and a power conversion efficiency of 0.80% was realized with P-1 as donor material.

关键词： Low band gap Conjugated polymers Electron-deficient aromatics Polymer solar cells.

Promotion effects of alkali metals on iron molybdate catalysts for CO_(2)catalytic hydrogenation

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Journal of Energy Chemistry 2023年第10期85卷 291-300,I0009页

作者： Yong Zhou Aliou Sadia Traore Deizi v.Peron Alan J.Barrios Sergei A.Chernyak Massimo Corda Olga v.Safonova Achim Iulian Dugulan Ovidiu Ersen Mirella virginie vitaly v.ordomsk. Andrei Y.Khodakov University of Lille CNRSCentrale LilleUniversity of ArtoisUMR 8181-UCCS-Unitéde Catalyse et Chimie du SolideLille F-59000France IPCMS UMR 7504 CNRSUniversitéde Strasbourg23 rue du LoessBP 43Cedex 267034 StrasbourgFrance PSI CH-5232 VilligenSwitzerland Fundamental Aspects of Materials and Energy Group Delft University of TechnologyMekelweg 15Delft 2629 JBNetherlands

CO_(2)hydrogenation is an attractive way to store and utilize carbon dioxide generated by industrial processes,as well as to produce valuable chemicals from renewable and abundant *** catalysts are commonly used for the hydrogenation of carbon oxides to ***-molybdenum catalysts have found numerous applications in catalysis,but have been never evaluated in the CO_(2)*** this work,the structural properties of iron-molybdenum catalysts without and with a promoting alkali metal(Li,Na,K,Rb,or Cs)were characterized using X-ray diffraction,hydrogen temperatureprogrammed reduction,CO_(2)temperature-programmed desorption,in-situ^(57)Fe Mossbauer spectroscopy and operando X-ray adsorption *** catalytic performance was evaluated in the CO_(2)*** the reaction conditions,the catalysts undergo the formation of an iron(Ⅱ)molybdate structure,accompanied by a partial reduction of molybdenum and carbidization of *** rate of CO_(2)conversion and product selectivity strongly depend on the promoting alkali metals,and electronegativity was identified as an important factor affecting the catalytic *** CO_(2)conversion rates were observed with the promoters having higher electronegativity,while low electronegativity of alkali metals favors higher light olefin selectivity.

关键词： CO_(2)utilization Iron molybdate catalysts Promotion Alkali metals Light olefins In-situ characterization

Thermochemistry of Heteroatomic Compounds:Calculation of the heat of Combustion and the heat ofFormation of some Bioorganic Molecules with DifferentHydrophenanthrene Rows

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Open Journal of Physical Chemistry 2011年第1期1卷 1-5页

作者： vitaly v. Ovchinnikov 不详

On the basis of the known experimental heats of combustions of the seventeen alkanes in condensed state, the general equation has been deduced, in which i and f are correlation coefficients, N and g are a numbers of valence electrons and lone electron pairs of heteroatoms in molecule. The presented dependence has been used for the calculation of the heats of combustion of thirteen organic molecules with biochemical properties: holestan, cholesterol, methyl-cholesterol, ergosterol, vitamin-D2, estradiol, androstenone, testosterone, androstanedione, morphine, morphinanone, codeine and pentasozine. It is noted that good convergence was obtained within the limits of errors of thermochemical experiments known in the literature and calculations of the heats of combustion for some of them were conducted. With the application of Hess law and the heats of vaporization , which has been calculated with the use of a topological solvation index of the first order , the heats of formation for condensed and gaseous phases were calculated for the listed bioorganic molecules.

关键词： Alkanes Biochemical Molecules the Heat of Combustion Heat of Formation Heat of vaporization Topological Solvation Index

IR-transparent MgO-Gd_(2)O_(3) composite ceramics produced by self-propagating high-temperature synthesis and spark plasma sintering

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Journal of Advanced Ceramics 2021年第2期10卷 237-246页

作者： Dmitry A.Permin Maksim S.Boldin Alexander v.Belyaev Stanislav S.Balabanov vitaly A.Koshkin Atrem A.Murashov Igor v.Ladenkov Evgeny A.Lantsev Ksenia E.Smetanina Nadia M.Khamaletdinova G.G.Devyatykh institute of chemistry of high-purity substances of the ras nizhny novgorod603137russia Lobachevsky state university of nizhny novgorod nizhny novgorod603950russia “Joint-stock company”research and production enterprise“salut” nizhny novgorod603950russia G.A.Razuvaev institute of organometallic chemistry of the ras nizhny novgorod603137russia

A glycine–nitrate self-propagating high-temperature synthesis(SHS)was developed to produce composite MgO-Gd_(2)O_(3) *** X-ray powder diffraction(XRD)analysis confirmed the SHS-product consists of cubic MgO and Gd_(2)O_(3) phases with nanometer crystallite size and retains this structure after annealing at temperatures up to 1200℃.Near full dense high IR-transparent composite ceramics were fabricated by spark plasma sintering(SPS)at 1140℃and 60 *** in-line transmittance of 1 mm thick MgO-Gd_(2)O_(3) ceramics exceeded 70%in the range of 4–5 mm and reached a maximum of 77%at a wavelength of 5.3 *** measured microhardness Hv0.5 of the MgO-Gd2O3 ceramics is 9.5±0.4 GPa,while the fracture toughness(KIC)amounted to 2.0±0.5МPa·m1/*** characteristics demonstrate that obtained composite MgO-Gd_(2)O_(3) ceramic is a promising material for protective infra-red(IR)windows.

关键词： MgO-Gd_(2)O_(3) self-propagating high-temperature synthesis(SHS) spark plasma sintering(SPS) optical properties infra-red(IR)ceramics

基于剪切模量和热分析数据研究Zr_(50-x)Cu_(34)Ag_(8)Al_(8)Pd_(x)(x=0,2)非晶合金缺陷浓度演化

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物理学报 2021年第14期70卷 266-274页

作者：程怡婷 Andrey S.Makarov Gennadii v.Afonin vitaly A.Khonik 乔吉超西北工业大学力学与土木建筑学院西安710072 Department of General Physics Voronezh State Pedagogical UniversityVoronezh 394043Russia

非晶合金具有独特物理和力学性能,如何建立非晶合金微观结构非均匀性与物理/力学性能之间的关联是非晶固体的重要研究课题之一.微合金化是调控非晶合金微观结构有效手段之一.本研究以玻璃形成能力优异的Zr_(50-x)Cu_(34)Ag_(8)Al_(8)Pd_... 详细信息

非晶合金具有独特物理和力学性能,如何建立非晶合金微观结构非均匀性与物理/力学性能之间的关联是非晶固体的重要研究课题之一.微合金化是调控非晶合金微观结构有效手段之一.本研究以玻璃形成能力优异的Zr_(50-x)Cu_(34)Ag_(8)Al_(8)Pd_(x)(x=0,2)非晶合金为模型合金,借助差示扫描量热仪和电磁声转换设备,研究非晶合金铸态、弛豫态和结晶态热流和剪切模量随温度的演化规律,以及物理时效(低于玻璃转变温度)过程剪切模量的变化随时间演化规律.基于自间隙原子理论,利用热流曲线表征非晶合金在相同热历史剪切模量热效应.通过分析铸态和弛豫态自间隙缺陷浓度和激活能谱,发现结构弛豫导致自间隙缺陷浓度减小,诱导剪切模量随温度演化偏离软化过程,并伴随体系放热.与此同时,研究发现添加微量Pd元素可抑制模型合金体系原子迁移,增加特征弛豫时间.本研究从非晶合金模量热效应角度进一步理解非晶合金微观结构非均匀性.

关键词：非晶合金缺陷浓度剪切模量微观结构非均匀

Delocalization of dark and bright excitons in flat-band materials and the optical properties of v_(2)O_(5)

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npj Computational Materials 2022年第1期8卷 882-890页

作者： vitaly Gorelov Lucia Reining Martin Feneberg Rüdiger Goldhahn AndréSchleife Walter R.L.Lambrecht Matteo Gatti LSI CNRSCEA/DRF/IRAMISÉcole PolytechniqueInstitut Polytechnique de ParisF-91120PalaiseauFrance European Theoretical Spectroscopy Facility https://www.etsf.eu/ Institute of Physics Otto von Guericke University MagdeburgUniversitätsplatz 239106MagdeburgGermany Department of Materials Science and Engineering University of Illinois at Urbana-ChampaignUrbanaIL61801USA Materials Research Laboratory University of Illinois at Urbana-ChampaignUrbanaIL61801USA National Center for Supercomputing Applications University of Illinois at Urbana-ChampaignUrbanaIL61801USA Department of Physics Case Western Reserve UniversityClevelandOH44106-7079USA Synchrotron SOLEIL L’Orme des MerisiersSaint-Aubin BP 48F-91192Gif-sur-YvetteFrance

The simplest picture of excitons in materials with atomic-like localization of electrons is that of Frenkel excitons,where electrons and holes stay close together,which is associated with a large binding ***,using the example of the layered oxide v_(2)O_(5),we show how localized charge-transfer excitations combine to form excitons that also have a huge binding energy but,at the same time,a large electron-hole distance,and we explain this seemingly contradictory *** anisotropy of the exciton delocalization is determined by the local anisotropy of the structure,whereas the exciton extends orthogonally to the chains formed by the crystal ***,we show that the bright exciton goes together with a dark exciton of even larger binding energy and more pronounced *** findings are obtained by combining first principles many-body perturbation theory calculations,ellipsometry experiments,and tight binding modelling,leading to very good agreement and a consistent *** explanation is general and can be extended to other materials.

关键词： structure anisotropy finding