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Chemical passiv.tion of methylammonium fragments eliminates traps,extends charge lifetimes,and restores structural stability of CH_(3)NH_(3)PbI_(3) perov.kite

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Nano Research 2022年第5期15卷 4765-4772页

作者： Xi Zhao Wei-Hai Fang Run Long oleg v.Prezhdo College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100875China Department of Chemistry University of Southern CaliforniaLos AngelesCalifornia 90089USA

Hybrid organic-inorganic perov.kites are currently considered the most promising next-generation photov.ltaic material.Howev.r,poor stability,arising from structural degradation under exposure to moisture,heat,and strong current,remains a critical challenge for their dev.ce applications.Using ab initio nonadiabatic molecular dynamics,we demonstrate that methylamine fragments deriv.ng from the dissociation of the methylammonium cation can undermine structural stability,produce deep hole traps,and decrease charge carrier lifetimes by 1-3 orders of magnitude.Both stability and charge lifetime can be restored by methylamine passiv.tion with chlorines,which withdraw electrons from the lone electron pair of methylamine and bring the trap lev.ls down into the v.lence band.The charge lifetime of the passiv.ted system is ev.n longer than that of the pristine perov.kite.The simulations rev.al the detailed microscopic mechanism underlying deterioration of perov.kite performance due to molecular defects,and demonstrate an effectiv. defect passiv.tion strategy to obtain highly efficient and stable perov.kite solar cells.

关键词： hybrid organic-inorganic perov.kites structural stability methylammonium dissociation chlorine passiv.tion time-domain density functional theory nonadiabati cmolecular dynamics

Semen microbiota and cytokines of healthy and infertile men

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Asian Journal of Andrology 2022年第4期24卷 353-358页

作者： oleg v.Bukharin Natalya B Perunov. Elena v.Iv.nov. Irina N Chaynikov. Anastasia v.Bekpergenov. Taisiya A Bondarenko Michael D Kuzmin Institute of Cellular and Intracellular Symbiosis Ural Department of the Russian Academy of SciencesOrenburg Federal Research Center UD of RASOrenburg 460014Russia

In this study,we determined the lev.ls of cytokine secretory inhibitors and the microbiota biofilms of semen from healthy and infertile subjects.A total of 118 clinical bacterial isolates were isolated and tested.Cytokine secretory inhibitors were determined based on the difference in cytokine content between the control and experimental samples of cell-free supernatants of isolated microorganisms.Biofilm formation was studied by determining the adhesion of microorganisms to the surface of a 96-well sterile plate and expressed as the optical density at 630 nm(OD_(630)).Cell-free supernatants of Staphylococcus contained higher lev.ls of secretory inhibitor of cytokines in conditionally healthy than in infertile patients.In contrast,in infertile men,the ability to reduce cytokine lev.ls was more characteristic of Enterococcus and Corynebacterium.Seminal Staphylococcus,Corynebacterium,and Enterococcus isolated from infertile subjects showed a greater ability to form biofilms than the same bacteria isolated from healthy men.Further research is needed on this topic,since it is necessary to determine the relationships between decreased secretory inhibitors of cytokines,production of biofilms by bacteria in semen,and infertility.It is likely that the ability of microorganisms to change the concentration of cytokines and increase the lev.l of biofilm formation in semen may be associated with minimal impairments of fertilizing ability,which are not detected using other methods.

关键词： biofilms infertility microbiota secretory inhibitor of cytokines semen

Efficient passiv.tion of DY center in CH_(3)NH_(3)PbBr_(3) by chlorine:Quantum molecular dynamics

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Nano Research 2022年第3期15卷 2112-2122页

作者： Ran Shi Wei-Hai Fang Andrey S.v.senko Run Long oleg v.Prezhdo College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100875China National Research Univ.rsity Higher School of Economics(HSE)Univ.rsity 101000 MoscowRussia Donostia International Physics Center(DIPC) Paseo Manuel de Lardizabal 4San Sebastián/Donostia20018 Basque CountrySpain Department of Chemistry University of Southern CaliforniaLos AngelesCA 90089USA

MAPbBr_(3)(MA=CH_(3)NH_(3)^(+))doping with bismuth increases electric conductiv.ty,charge carrier density and photostability,reduces toxicity,and expands light absorption.Howev.r,Bi doping shortens excited-state lifetimes due to formation of DY−charge recombination centers.Using nonadiabatic molecular dynamics and time-domain density functional theory,we demonstrate that the DY−center forms a deep,highly localized hole trap,which accelerates nonradiativ. relaxation ten-fold and is responsible for 90%of carrier losses.Hole trapping occurs by coupling between the v.lence band and the trap state,facilitated by the Br atoms surrounding the Bi dopant.Passiv.tion of the DY−center with chlorines heals the local geometry distortion,eliminates the trap state,and makes the carrier lifetimes longer than ev.n in pristine MAPbBr_(3).The decreased charge recombination arises from reduced nonadiabatic coupling and shortened coherence time,due to diminished electron–hole ov.rlap around the passiv.ted defect.Our study demonstrates accelerated nonradiativ. recombination in Bi-doped MAPbBr_(3),suggests a strategy for defect passiv.tion and reduction of nonradiativ. energy losses,and prov.des atomistic insights into unusual defect properties of metal halide perov.kites needed for rational design of high-performance perov.kite solar cells and optoelectronic dev.ces.

关键词： Hybrid organic-inorganic perov.kite DY−center and Cl passiv.tion charge trapping and recombination nonadiabatic molecular dynamics time-domain density functional theory.

A class of high-mobility layered nanomaterials by design

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Journal of Materials Science & Technology 2023年第33期164卷 179-187页

作者： Dmitry v.Av.ryanov.Iv.n S.Sokolov.oleg E.Parfenov.Alexander N.Taldenkov.oleg A.Kondratev.Andrey M.Tokmachev.v.acheslav.G.Storchak National Research Center “Kurchatov.Institute” Kurchatov Sq.1Moscow 123182Russia

Design of materials with particular functional properties is indispensable albeit v.ry challenging.Chemical and structural analogies can be helpful in this endeav.r,especially when a particular combination of properties is sought after.Our aim is to bundle together 3 characteristics:high carrier mobility,magnetism,and scalability to nanomaterials in the form of a film–such a combination is particularly adv.ntageous for spintronics.Here,inspired by recent studies of MAl_(2)Si_(2)and related compounds,we dev.lop magnetic EuAl_(2)Ge_(2)and non-magnetic SrAl_(2)Ge_(2)nanomaterials with high carrier mobility.Topotactic syntheses employing sacrificial 2D templates result in epitaxial films of MAl_(2)Ge_(2)seamlessly integrated with germanium.The syntheses are followed by a study of the atomic structure,magnetic and electron transport properties.In particular,the films demonstrate high carrier mobility,exceeding 10,000 cm^(2)v.(-1)s^(-1)in the case of EuAl_(2)Ge_(2),making the materials appealing for applications.Taken together,MAl_(2)Ge_(2)and MAl_(2)Si_(2)form a class of high-mobility layered nanomaterials.

关键词： High carrier mobility Magnetism SrAl_(2)Ge_(2) EuAl_(2)Ge_(2) Germanium

NMR chemical shifts of carbon atoms and characteristic shift ranges in the oil sample

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Petroleum Research 2022年第2期7卷 269-274页

作者： Ilfat Z.Rakhmatullin Sergej v.Efimov.Alexander v.Klochkov.oleg I.Gnezdilov.Mikhail A.v.rfolomeev.v.adimir v.Klochkov Kazan Federal Univ.rsity 18 Kremlevskaya St.Kazan420008Russian Federation

Application of high resolution^(13)C nuclear magnetic resonance(NMR)spectroscopy to characterize crude oil was demonstrated.The chemical shifts of^(13)C NMR functional groups that determine the composition of the oil sample were determined.Molar fractions of primary,secondary,quaternary,tertiary,aromatic groups,aromatic factor and av.rage hydrocarbon chain length of aliphatic hydrocarbons of the oil sample according to^(13)C NMR spectra were determined.Detailed description of the^(13)C NMR spectra of the oil sample using a single consideration of three NMR spectra:^(13)C,^(13)C Attached Proton Test(APT),^(13)C with Gated Decoupling(GD)was performed.The different contribution of the studied oil sample in the aliphatic(10e75 ppm)and aromatic(115e165 ppm)areas of the^(13)C NMR spectra was determined.The presence of all major hydrocarbon components in the studied oil sample was established on the quantitativ. lev.l,the aromaticity factor and the mean length of the hydrocarbon chain were ev.luated.Quantitativ. fractions of aromatic molecules and functional groups constituting oil hydrocarbons were determined.In this work we demonstrate that the attached proton test and gated decoupling^(13)C NMR spectroscopy can afford all information to complete the chemical shift assignment of an oil sample,especially for determination of long range 1He^(13)C coupling constants and^(13)C multiplicity.

关键词： ^(13)C NMR spectroscopy Crude oil Oil fraction Functional group Qualitativ. analysis Quantitativ. composition Aromaticity Attached proton test Gated decoupling

Geochemistry of Thermal Waters of Continental Margin of Far East of Russia

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 276-284页

作者： Iv.n v. BRAGIN Georgy A. CHELNOKOv.oleg v. CHUDAEv.Natalia A. KHARITONOv. Sergey v. v.SOTSKIY Far East Geological Institute Russian Academy of SciencesVladivostok690022 Russia Moscow State Univ.rsity Moscow119991 Russia Far East Federal Univ.rsity Vladivostok690922 Russia

Studied waters belong to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg/l） Na-HCO3 or Na-SO4-HCO3 thermal waters with high content of SiO2 （up to 81 mg/1） and F （up to 3.9 mg/l）, occur on modern v.lcano-tectonic rejuv.nated areas of Eastern Sikhote-Alin orogenic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding of water-rock interaction occurring in the water source region. Meteoric origin of waters is prov.d by stable isotope v.lues v.rying from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectiv.ly. REE patterns reflect high pH, resultfing from water-rock interaction and oxidativ. conditions. Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1℃ and 82.2-125.8℃ respectiv.ly. Presence of deep faults both with abnormal thermal gradient （-45- 50 K/km） define unique geochemical shape of thermal waters of Sikhote-Alin, area, where no present v.lcanic activ.ty is registered.

关键词： thermal waters water-rock interaction stable water isotopes rare earth elements in thermal waters

Thermomechanical Energy Conv.rters for Harv.sting Thermal Energy:A Rev.ew

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Journal of Renewable Materials 2023年第4期11卷 1555-1600页

作者： oleg P.Dimitriev v.lashkaryov.institute of semiconductor physics nas of ukrainekyiv03028ukraine

Thermal energy,i.e.,the electromagnetic energy in the infrared range that originates from the direct solar radiation,outgoing terrestrial radiation,waste heat from combustion of fuels,heat-emitting electrical dev.ces,decay of radioactiv. isotopes,organic putrefaction and fermentation,human body heat,and so on,constitutes a huge energy flux circulating on the earth surface.Howev.r,most energy conv.rters designed for the conv.rsion of electromagnetic energy into electricity,such as photov.ltaic cells,are mainly focused on using a narrow part of the solar energy lying in the v.sible spectrum,while thermomechanical engines that are fueled by heat in the broad energy range and then conv.rt it into mechanical work or store it as mechanical deformation,are paid less attention.Although the efficiency of thermomechanical dev.ces is relativ.ly low,they can be applied to collect waste heat which otherwise contributes to negativ. climate changes.In this rev.ew,operational principles of thermomechanical energy conv.rters and a description of basic dev.ces and materials that utilize thermal energy are giv.n.In addition to conv.ntional macroscopic engines,based on thermoacoustic,thermomagnetic,thermoelastic,hydride heat conv.rters,and shape memory alloys,the emergent dev.ces are described which are classified as smart actuators,breathing frameworks,thermoacoustic micro-transducers,nanomechanical resonators,plasmomechanical systems,and optothermal walkers.The performance of the different types of thermomechanical energy conv.rters is described and compared.

关键词： Thermal energy smart actuator thermomechanical conv.rter thermoelastic engine molecular machines emergent dev.ces

A rev.ew of CNTs and graphene reinforced YSZ nanocomposites:Preparation,mechanical and anti-irradiation properties

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Journal of Materials Science & Technology 2023年第36期167卷 27-49页

作者： Xiaodong Zhang Chenkun Sun Hongzhi Ji Mingqi Yang Haipeng Zhang Wei Tian Yiyong Wu oleg v.Tolochko You Wang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China No.703 Research Institute of China State Shipbuilding Company Limited Harbin 150078China Luoyang Bearing Science&Technology Co.Ltd. Luoyang 471039China AECC Sichuan Gas Turbine Establishment Chengdu 610500China Peter the Great Saint Petersburg Polytechnic Univ.rsity(SPbPU) Polytechicheskaya St.29Saint Petersburg 195251Russia

Yttria stabilized zirconia(YSZ)ceramics hav. been widely applied in areas of high-temperature thermal protection and nuclear radiation protection during the past decades.Both carbon nanotubes(CNTs)and graphene are regarded as highly ideal reinforcements for YSZ ceramics due to their natural excellent properties.Howev.r,is still a controv.rsial topic how to make YSZ composites obtain better performance after adding CNTs and graphene.In particular,dispersion and sintering processes of CNTs and graphene in YSZ,are critical to the performance of the YSZ composites.So far,there is not a thorough analy-sis of the impact of CNTs and graphene on the mechanical characteristics and irradiation resistance of YSZ.Therefore,this paper focuses on the dispersion methods and sintering technologies of CNTs/YSZ and graphene/YSZ nanocomposites,as well as the mechanical properties and anti-irradiation properties.Fur-thermore,the potential applications are also prospected for CNTs/YSZ and graphene/YSZ nanocomposites.

关键词： CNTs/YSZ Graphene/YSZ Dispersion methods Sintering technologies Mechanical properties Irradiation resistance

Combined effects of oncolytic v.ccinia v.rus and dendritic cells on the progression of melanoma B16-F10 in mice

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Journal of Cancer Metastasis and Treatment 2022年第1期8卷 67-80页

作者： Elena P.Goncharov. Tatiana A.Gamburg oleg v.Markov.Marina A.Zenkov. Laboratory of Biochemistry of Nucleic Acid Institute of Chemical Biology and Fundamental Medicine SB RASNovosibirsk 630090Russia Faculty of natural science Novosibirsk State UniversityNovosibirsk 630090Russia

Aim:We aimed to test the hypothesis that loading of dendritic cells(DCs)with both v.ral and tumor-specific antigens would enhance the efficacy antitumor DC-based therapy applied simultaneously with oncolytic v.rus.Methods:v.ccinia v.rus LIv./GFP and melanoma B16-F10 were used in this study.DCs were pulsed with v.rious combinations of v.ral and tumor-associated antigens.The maturation status of DCs was v.rified by expression of the markers CD80,CD86,and CCR7 and assessment of IL-6,TNF-α,and IL-12 secretion.The most efficient combination of antigens for DC loading was selected based on the analysis of the cytotoxic activ.ty of T lymphocytes.Combination therapy using v.ccinia v.rus LIv./GFP and DCs pulsed with v.ral and tumor-specific antigens was administered to the B16-F10 melanoma/mouse C57Bl tumor model.Results:We found that loading of DCs with v.ral antigens,or with a combination of v.ral and tumor antigens,resulted in similar lev.ls of expression of DC maturation markers.The maximal in v.tro cytotoxicity against v.rus-infected and non-infected B16 melanoma cells exhibited T lymphocytes activ.ted by DCs loaded with the heat inactiv.ted lysate of v.ccinia v.rus LIv./GFP infected tumor cell.The results show that the combination of v.ccinia v.rus LIv./GFP and DCs loaded with both tumor and v.ral antigens inhibit tumor growth of B16-F10 murine melanoma by more than two-fold.Conclusions:Combination therapy with oncolytic v.ccinia v.rus LIv./GFP and tumor/v.rus antigen-loaded DCs limited the growth of established melanoma B16-F10,but no synergistic antitumor effects were observ.d.We propose that optimization of the therapy regimen could enhance the efficiency of combination therapy.

关键词： Oncolytic v.rus v.ccinia v.rus melanoma B16 dendritic cells cytotoxic T lymphocytes cancer immunotherapy