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Uranium Isotope variations(234U/238U and 238U/235U)and Behavior of U-Pb Isotope System in the vershinnoe Sandstone-Type Uranium Deposit,vitim Uranium Ore District,Russia

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Journal of Earth Science 2022年第2期33卷 317-324页

作者： v.N.Golubev I.v.Chernyshev B.T.Kochkin N.N.tarasov G.v.Ochirova A.v.Chugaev Institute of Geology of Ore Deposits PetrographyMineralogy and GeochemistryRussian Academy of SciencesMoscow 119017Russia

The U-Pb isotope system and uranium isotope composition(235U/238U and 234U/238U)were studied in a number of samples from the vertical section of the uranium ore body at the vershinnoe sandstone-type deposit,vitim uranium ore district,Russia.These parameters were determined to broadly vary.Deviations of the 234U/238U ratio from the equilibrium value indicate that the uranium ore was not completely conserved during the postore stage,and uranium was determined to continue migrating at the deposit.Comparison of the U-Pb isotope age value and 234U/238U isotope ratio provides an insight into the migrate direction of uranium in the ore body.The broad variations(137.377–137.772)in the 238U/235U ratio over the vertical section of the ore body can be explained by the different settings of the samples relative to the ore deposition front and changes in the redox conditions when this front shifted.The fact that theδ238U and K234/238 values are correlated indicates that the transfer of the 234U isotope into the aqueous phase may have been coupled with isotope fractionation in the 238U-235U system during the postformation uranium migration within the orebody.

关键词： sandstone-type uranium deposit U-Pb age uranium isotope composition ore deposit geology

Evidence for polarization-induced phase transformations and degradation in CH_(3)NH_(3)PbI_(3)

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Nano Research 2023年第7期16卷 9435-9442页

作者： Aleksei Yu.Grishko Maria A.Komkova Ekaterina I.Marchenko Alexandra v.Chumakova Alexey B.tarasov Eugene A.Goodilin Andrei A.Eliseev Department of Materials Science MSU-BIT UniversityShenzhen 517182China Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia Department of Materials Science Lomonosov Moscow State UniversityMoscow 119991Russia European Synchrotron Radiation Facility F-38042 GrenobleFrance

In solar cells,hybrid halide perovskites operate under constant bias,thus their stability towards electric field-induced degradation is of key importance.Here we report on evidence of previously unidentified electric field-induced transitions and degradation path of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))using elemental and phase mapping.Thin films of MAPbI_(3) were deposited onto 1-2μm-pitch interdigitated electrodes and subjected to direct current(DC)-polarization.The MAPbI_(3) layer polarized withv/μm DC electric field undergoes pronounced ion redistribution to methylammonium-rich MAPbI_(3)-y(yvokes degradation of MAPbI_(3).Using nanofocus grazing-incidence wide-angle X-ray scattering(GIWAXS),we unambiguously showed that the bias voltage induces the transformation ofβ-MAPbI_(3) to metastableδ-MAPbI_(3) polymorph via alignment of polar organic cation with the electric field.This transformation is partially reversible upon field removal.However,once formed,δ-MAPbI_(3) disrupts the morphology of pristine film and undergoes decomposition toβ-MAPbI_(3)(β-MAPI)and PbI_(2).With the aforementioned compositional and phase changes,only MA-rich part serves as the charge separation layer,while the I-rich excitation is blocked with the PbI_(2) barrier serving as holes trapping layer.These observations reveal the intermediate steps in electric-field-driven degradation of halide perovskites and show the role of polar cations in the process,which is instructive for further material design with higher stability metrics.

关键词： halide perovskites stability degradation electric field ionic conductivity stoichiometry

Advances in the development of new biomarkers for Alzheimer’s disease

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Translational Neurodegeneration 2022年第1期11卷 601-624页

作者： Timofey O.Klyucherev Pawel Olszewski Alena A.Shalimova vladimir N.Chubarev vadim v.tarasov Misty M.Attwood Stina Syvänen Helgi B.Schiöth Department of Neuroscience Functional PharmacologyUniversity of Upp-salaUppsalaSweden Department of Pharmacology Institute of PharmacyI.M.Sechenov First Moscow State Medical UniversityMoscowRussia Institute of Translational Medicine and Biotechnology I.M.Sechenov First Moscow State Medical UniversityMoscowRussia Department of Public Health and Caring Sciences Rudbeck LaboratoryUppsala UniversityUppsalaSweden.

Alzheimer’s disease(AD)is a complex,heterogeneous,progressive disease and is the most common type of neurodegenerative dementia.The prevalence of AD is expected to increase as the population ages,placing an additional burden on national healthcare systems.There is a large need for new diagnostic tests that can detect AD at an early stage with high specificity at relatively low cost.The development of modern analytical diagnostic tools has made it possible to determine several biomarkers of AD with high specificity,including pathogenic proteins,markers of synaptic dysfunction,and markers of inflammation in the blood.There is a considerable potential in using microRNA(miRNA)as markers of AD,and diagnostic studies based on miRNA panels suggest that AD could potentially be determined with high accuracy for individual patients.Studies of the retina with improved methods of visualization of the fundus are also showing promising results for the potential diagnosis of the disease.This review focuses on the recent developments of blood,plasma,and ocular biomarkers for the diagnosis of AD.

关键词： Alzheimer’s disease Amyloid beta peptides Biomarkers Blood Cytokines Inflammation MicroRNA Ocular biomarkers

Emulsification for castor biomass oil

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 96-101页

作者： Dongxiang ZHANG Yuanping LIN Anmei LI v.v.tarasov School of Chemical Engineering and the Environment Beijing Institute of TechnologyBeijing 100081China D.I.Mendeleev University of Chemical Technology of Russia 125190 MoscowRussia

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance,centrifuge stability,demulsification time in quiescence,appearance of the droplets,and viscosity.The best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan monostearate.Correlation exists between the stability of emulsion and the viscosity/particle size of the droplets,with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water system.Methanol added to the castor oil-water system may decrease the viscosity of the emulsion.Comparing the castor oil-water emulsion with methanol-castor oil-water emulsion,the optimal hydrophilic and lipophilic balance(HLB)value based on castor oil-water system was acquired between 6.6 and 7.5,while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and 6.0.The optimal HLB value of methanolcastor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.

关键词： castor oil biomass oil emulsification stability viscosity corrosivity

How to stabilize standard perovskite solar cells to withstand operating conditions under an ambient environment for more than 1000 hours using simple and universal encapsulation

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Journal of Energy Chemistry 2023年第3期78卷 246-252,I0008页

作者： Nikolai A.Belich Andrey A.Petrov Pavel A.Ivlev Natalia N.Udalova Alla A.Pustovalova Eugene A.Goodilin Alexey B.tarasov Laboratory of New Materials for Solar Energetics Faculty of Materials ScienceLomonosov Moscow State University119991 MoscowRussia Department of Chemistry Lomonosov Moscow State University119991 MoscowRussia

We introduce a simple and universal scalable encapsulation strategy for perovskite solar cells based on thermal vacuum evaporation of MgF2or MoO3-xcapping layer followed by sealing the device with glass and Uv-curable polymer.The proposed encapsulation method is beneficial to most of the other known encapsulation approaches being fully harmless to perovskite and transporting layers and processible at room temperature.vacuum deposition of the capping layer promotes efficient removal of water,oxygen and organic solvent residuals from the device prior to sealing and could be easily performed using standard equipment for metal electrode deposition.The proposed strategy is transferrable to any lab-scale perovskite solar cell prototypes regardless of their geometry and architecture and results in excellent stability of the devices in ambient air and long operating conditions.Upon the 1000 hours stability test at ambient air(30%-60% RH),the cells preserved 92.9% of their initial efficiency on average under 1 Sun illumination at constant maximum power point tracking(MPPT,ISOS-L-1) and over 96% under sto rage in the dark(ISOS-D-1),thus evidencing for the high effectiveness of the proposed encapsulation approach.

关键词： Perovskite solar cells Halide perovskites Encapsulation High stability ISOS-L-1

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：摩擦仪表面磨损摩擦学物理性能

静电场与表面活性剂对液-液体系相间传质动力学特性的影响

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北京理工大学学报 2008年第3期28卷 267-270页

作者：张东翔李安妹徐曦 tarasov v．v．北京理工大学化工与环境学院北京100081 俄罗斯门捷列夫化工大学俄罗斯莫斯科125190

在Lewis传质池外部施加不同方向的静电场激励,研究反萃传质体系Cu2+-HDEHP-CCl4/H2O在改变相主体搅拌速率、体系添加十二烷基硫酸钠、聚乙二醇辛基苯基醚、十六烷基三甲基溴化铵等条件时的传质动力学特性.研究发现:无静电场激励时,添加... 详细信息

在Lewis传质池外部施加不同方向的静电场激励,研究反萃传质体系Cu2+-HDEHP-CCl4/H2O在改变相主体搅拌速率、体系添加十二烷基硫酸钠、聚乙二醇辛基苯基醚、十六烷基三甲基溴化铵等条件时的传质动力学特性.研究发现:无静电场激励时,添加十二烷基硫酸钠可提高传质速率42.0%,但添加聚乙二醇辛基苯基醚降低传质速率45.5%,添加十六烷基三甲基溴化铵降低传质速率19.8%;无表面活性剂时,不同方向的静电场均显著加速传质过程,正向静电场增幅达到114%;在垂直静电场作用下,体系添加聚乙二醇辛基苯基醚传质速率降低28.0%;在减速静电场作用下,体系添加十六烷基三甲基溴化铵传质速率降低16.0%;但体系添加十二烷基硫酸钠时,传质速率均被加速,最高达64.0%;提高搅拌速率不仅可以影响相间流体力学层,还可以改变相间分散层结构.

关键词：传质静电场表面活性剂相间结构

硫代杯[4]冠-4在硝酸体系中对Sr^(2+)的萃取

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化工学报 2015年第3期66卷 1035-1041页

作者：李洁周丽娟张东翔刘聪 tarasov v.v. 北京理工大学化工与环境学院北京100081 俄罗斯门捷列夫化工大学莫斯科125190

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、1H NMR和MS对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH2Cl2为稀释剂,在硝酸... 详细信息

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、1H NMR和MS对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH2Cl2为稀释剂,在硝酸浓度为3 mol·L-1,有机相中硫代杯[4]冠-4浓度为1×10-3 mol·L-1,水相中Sr2+浓度为5×10-4 mol·L-1,萃取温度为25℃,萃取80 min条件下,平均传质系数为1.36×10-5 m·s-1,Sr2+的分配比为0.69。分析了不同条件对硫代杯[4]冠-4对Sr2+的萃取影响,研究了萃取计量方程式,实验结果表明萃合物为{Sr(NO3)2}·{TCACE}。研究了TCACE对其他金属离子Mo6+、Ni2+、Ag+、Sn4+等的萃取效果,表明对Sr2+具有较好的选择性。

关键词：硫代杯冠-4 合成 Sr^2+ 萃取分离

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硝酸反萃体系中表面活性剂对传质的影响

化学工程 2003年第6期31卷 15-18页

作者：谭世语张东翔黄会清 tarasov v.v. 重庆大学化学工程系重庆400044 Department of Industrial Ecology D.I.Mendeleyev University of Chemical Technology of Russiamoscow125190

在改进的传质池中研究了 3种表面活性剂对硝酸反萃体系传质的影响。实验表明 ,在不加界面激励时 ,表面活性剂的存在大大降低硝酸反萃的传质系数 ;加界面激励时 ,阴、阳离子表面活性剂会增加硝酸反萃的传质系数 ,非离子表面活性剂则减小... 详细信息

在改进的传质池中研究了 3种表面活性剂对硝酸反萃体系传质的影响。实验表明 ,在不加界面激励时 ,表面活性剂的存在大大降低硝酸反萃的传质系数 ;加界面激励时 ,阴、阳离子表面活性剂会增加硝酸反萃的传质系数 ,非离子表面活性剂则减小传质系数。

关键词：界面激励表面活性剂反萃传质