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Permafrost distribution and temperature in the Elkon Horst, Russia

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Research in Cold and Arid Regions 2021年第2期13卷 107-122页

作者： Mikhail Zhelezniak QingBai Wu Anatolii Kirillin Zhi Wen aleksandr Zhirkov Vladimir Zhizhin Melnikov Permafrost Institute SB RAS Yakutsk 677000Russia State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesCASLanzhouGansu 730000China

The Elkon Horst is a geological structure that consists of heterogeneous strata with highly variable geocryological and temperature conditions. Gaining accurate knowledge of permafrost distribution patterns within this structure is of both scientific and practical importance. In mountainous terrain, the ground thermal regime is controlled by both surface and subsurface conditions. Surface conditions include snow cover characteristics, the presence or absence of vegetation, vegetation density, etc.. In contrast, subsurface conditions involve rock lithology or petrography, density, quantity and depth of fissures, groundwater, etc.. This article examines ground thermal regimes in various geomorphological settings based on temperature measurement data from geotechnical boreholes. The occurrence and extent of permafrost were evaluated for the entire horst area using direct and indirect methods. The maximum permafrost thickness measured in the Elkon Horst is 330 m, and the estimated maximum is 450 m at higher elevations. Thermophysical properties were determined for the major rock types, and the geothermal heat flux was estimated for the study area. The thermal conductivities were found to vary from 1.47 to 4.20 W/(m·K), and the dry bulk densities to range between 2,236 kg/m~3 and 3,235 kg/m~3. The average geothermal heat flux was estimated to be 44 mW/m~2.

关键词： permafrost ground temperature geothermal heat flux thermal conductivity horst

Influence of shielding gas and non-consumable electrode configuration on weld formation

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China Welding 2021年第4期30卷 17-24页

作者： aleksandr Savinov Oleg Polesskiy Vladimir Lysak Pavel Krasikov Artem Chudin Volgograd State Technical University Lenin av.28Volgograd400005Russia

The effect of the shielding gas composition and the cathode processing history on the weld formation quality during welding with a non-consumable electrode at high current was studied. The major reasons for pores, “waists” and undercuts formation during welding at high currents and speed are discrete melt movement to the solidification front due to the arc decline from the cathode axis and significant melt overhanging in the pool tail part caused by excessive peak pressure on the discharge axis. Cathode flow dispersion causes the lack of displacement of the molten metal which results in its laminar flow in the weld pool, uniform flow of the metal to the crystallization front and sound weld formation. The melt movement in the weld pool and eventually the welded joint quality is determined by the pressure distribution pattern on the welded metal surface and the anode spot lag from the electrode. It was demonstrated that non-consumable electrode configurations that provide arcing with a diffuse cathode spot and increased helium concentration in the inert atmosphere during welding with a conical electrode allow sound weld formation.

关键词： tungsten inert gas welding non-consumable electrode inert gas weld seam formation

An Integrated Oil Production Enhancement Technology Based on Waterflooding Energy Recovery

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Fluid Dynamics & Materials Processing 2023年第2期19卷 285-301页

作者： aleksandr Lekomtsev Vitaliy Bakaneev Ivan Stepanenko Petr Maximov Yulia Rozhkova Alexey Dengaev Wanli Kang Perm National Research Polytechnic University Perm614990Russian Department of Oil Field Development and Operation Gubkin Russian State University of Oil and GasMoscow119991Russia China University of Petroleum(East China) Qingdao266000China

A new integrated oil production enhancement technology based on water-flooding energy recovery is *** providing an extensive review of the existing scientific and technical literature on this subject,the proposed integrated technology is described together with the related process flow diagram,the criteria used to select a tar-get facility for its implementation and the outcomes of the laboratory studies conducted to analyze emulsion formation and separation ***,the outcomes of numerical simulations performed using Ansys CFX software are also *** to these results,using the proposed approach the incremental oil production may reach 1.2 t/day(with a 13%increase)and more,even at low flow rates(less than 10 t/day),thereby providing evidence for the benefits associated with this integrated technology.

关键词： Oil production jet pump waterflooding system energy recovery Ansys CFX

Pt-Al<sub>2</sub>OM<sub>3</sub>Composite Material Designed for Cyclic Production of Optical Glasses under High Temperature Conditions

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Journal of Materials Science and Chemical Engineering 2014年第3期2卷 30-36页

作者： aleksandr Bochegov aleksandr Ermakov Irina Vandysheva IFE UrFU Yekaterinburg Russia JSC Urals’ Innovation Technologies Yekaterinburg Russia

The article considers one of the possible approaches to the solution of an urgent issue of metal consumption reduction, increase of operating life and maximum operating temperature as well as reduction of irrecoverable losses of platinum products and alloys when operating under high temperature conditions, particularly for glassblowing and single crystal growing crucibles. A two-layered composite material based on platinum-group metals and corundum plasma ceramics is thoroughly investigated. A successful experience of crucibles exploitation, designed for production of high temperature optical glasses from the composite and results of the research on composite material specimens are described.

关键词： Sandwich-Structured Composite Material Plasmaceramics Platinum-Group Metals Reduction of Metal Consumption Crucibles for Glassblowing and Single Crystal Growing High Temperature Creep High Temperature Strength and Heat Resistance Irrecoverable Losses

Nanoscale inhibition of polymorphic and ambidextrous lAPP amyloid aggregation with small molecules

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Nano Research 2018年第7期11卷 3636-3647页

作者： aleksandr Kakinen Jozef Adamcik Bo Wang Xinwei Ge Raffaele Mezzenga Thomas P. Davis Feng Ding Pu Chun Ke ARC Centre of Excellence in Convergent Bio-Nano Science and Technology Monash Institute of Pharmaceutical Sciences Monash University 381 Royal Parade Parkville VIC 3052 Australia Food & Soft Materials Department of Health Sciences & Technology ETH Zurich Schmelzbergstrasse 9 LFO E23 8092 Zurich Switzerland Department of Physics andAstronomy Clemson University Clemson SC29634 USA Department of Chemistry Warwick University Gibbet Hill Coventry CV4 7AL UK

Understanding how small molecules interface with amyloid fibrils at the nanoscale is of importance for developing therapeutic treatments against amyloid-based diseases. Here, we show for the first time that human islet amyloid polypeptides （LAPP） in the fibrillar form are polymorphic, ambidextrous, and possess multiple periodicities. Upon interfacing with the small molecule epigallocatechin gallate （EGCG）, IAPP aggregation was rendered off-pathway and assumed a form with soft and disordered clusters, while mature IAPP fibrils displayed kinks and branching but conserved the twisted fibril morphology. These nanoscale phenomena resulted from competitive interactions between EGCG and the IAPP amyloidogenic region, as well as end capping of the fibrils by the small molecule. This information is crucial in delineating IAPP toxicity implicated in type 2 diabetes and for developing new inhibitors against amyloidogenesis.

关键词： islet amyloid polypeptides(LAPP) fibriUization persistence length small molecule discrete moleculardynamics (DMD)simulations inhibition

Tailoring the LiNbO_(3)coating of Ni-rich cathode materials for stable and high-performance all-solid-state batteries

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Nano Research Energy 2022年第3期1卷 4-10页

作者： Seyedhosein Payandeh Florian Strauss Andrey Mazilkin aleksandr Kondrakov Torsten Brezesinski Battery and Electrochemistry Laboratory Institute of NanotechnologyKarlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany Karlsruhe Nano Micro Facility Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany BASF SE Carl-Bosch-Str.3867056 LudwigshafenGermany

The research and development of advanced nanocoatings for high-capacity cathode materials is currently a hot topic in the field of solid-state batteries(SSBs).Protective surface coatings prevent direct contact between the cathode material and solid electrolyte,thereby inhibiting detrimental interfacial decomposition *** is particularly important when using lithium thiophosphate superionic solid electrolytes,as these materials exhibit a narrow electrochemical stability window,and therefore,are prone to degradation during battery *** we show that the cycling performance of LiNbO_(3)-coated Ni-rich LiNi_(x)Co_(y)Mn_(z)O_(2)cathode materials is strongly dependent on the sample history and(coating)synthesis *** demonstrate that post-treatment in a pure oxygen atmosphere at 350℃results in the formation of a surface layer with a unique microstructure,consisting of LiNbO_(3)nanoparticles distributed in a carbonate *** tested at 45℃and C/5 rate in pellet-stack SSB full cells with Li_(4)Ti_(5)O_(12)and Li_(6)PS_(5)Cl as anode material and solid electrolyte,respectively,around 80%of the initial specific discharge capacity is retained after 200 cycles(~160 mAh·g^(−1),~1.7 mAh·cm^(−2)).Our results highlight the importance of tailoring the coating chemistry to the electrode material(s)for practical SSB applications.

关键词： solid-state battery layered Ni-rich oxide cathode superionic solid electrolyte protective surface coating side reactions

Scanning Mode Application of Neutron-Gamma Analysis for Soil Carbon Mapping

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Pedosphere 2019年第3期29卷 334-343页

作者： aleksandr KAVETSKIY Galina YAKUBOVA Nikolay SARGSYAN Clyde WIKLE Stephen A. PRIOR Henry Allen TORBERT Bryan A. CHIN United States Department of Agriculture-Agricultural Research Service (USDA-ARS) National Soil Dynamics Laboratory Auburn AL 36832 (USA) Auburn University Detection and Food Safety Center Samuel Ginn College of Engineering Auburn AL 36849 (USA)

Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A Global Positioning System(GPS) device and softwares required to simultaneously acquire gamma signals and geographical positions during scanning operations were added to an existing measurement system. The reliability of soil carbon measurements in scanning mode was demonstrated to be in agreement with results acquired from static mode. The error analysis indicated that scanning measurements can be conducted with the same accuracy as static measurements in approximately one fourth the time. To obtain results suitable for mapping analogous to traditional chemical analyses(i.e.,± 0.5 in weight percent or ± 0.5 w%), scanning time over a given site should be ca. 15 min using the current measurement system configuration. Based on this measurement time, a reasonable towing speed of 3–5 km h^-1, the necessity for complete site coverage during scanning, the number of sites(within the surveyed field), and the required total measurement time can be estimated. Soil carbon measurements for 28 field sites(total area ca. 2.5 ha) were conducted in ca. 8 h. Based on acquired data,a soil carbon distribution map was constructed utilizing various softwares. The surveyed field area included an asphalt road that had carbon readings higher than the surrounding land. The clarity with which these carbon-rich zones were delineated on the constructed map represents evidence supporting the veracity of this method. Neutron-gamma analysis technology can greatly facilitate timely construction of soil carbon maps.

关键词： ArcGIS Google Earth Pro IGOR scanning technology soil carbon distribution map soil carbon storage

Laboratory diagnosis of nonpolio enteroviruses:A review of the current literature

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Biosafety and Health 2023年第2期5卷 112-119页

作者： Tarek Itani Vladislav Chalapa aleksandr Semenov aleksandr Sergeev Yekaterinburg Research Institute of Viral Infections SRC VB VEKTORRospotrebnadzorYekaterinburgRussia Ural State Medical University YekaterinburgRussia

Infections by nonpolio enteroviruses(EVs)are highly prevalent,particularly among children and neonates,where they may cause substantial morbidity and *** diagnosis of these viral infections is important in patient prognosis and guidance of clinical *** the laboratory diagnosis of non-polio EVs is mainly based on molecular techniques,classical virus-isolation techniques are still used in refer-ence *** techniques,such as antigen detection and serology,are becoming obsolete and rarely used in *** important part of diagnosis and surveillance of EV infections is viral typing by VP1 gene sequencing using conventional Sanger technique and more recently,full-genome next-generation *** latter allows the typing of all EVs,better investigation of EV outbreaks,detection of coinfec-tion,and identification of severity markers in the EV genome.

关键词： Nonpolio enteroviruses Virus isolation Nucleic acid amplification tests Sanger sequencing Next-generation sequencing

Functionality of a bicistronic construction containing HEXA and HEXB genes encoding β-hexosaminidase A for cell-mediated therapy of GM2 gangliosidoses

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Neural Regeneration Research 2022年第1期17卷 122-129页

作者： Alisa A.Shaimardanova Daria S.Chulpanova Valeriya V.Solovyeva aleksandr M.Aimaletdinov Albert A.Rizvanov Institute of Fundamental Medicine and Biology Kazan Federal UniversityKazanRussia

Tay-Sachs disease and Sandhoff disease are severe hereditary neurodegenerative disorders caused by a deficiency ofβ-hexosaminidase A(HexA)enzyme,which results in the accumulation of GM2 gangliosides in the nervous system *** this work,we analyzed the efficacy and safety of cell-mediated gene therapy for Sandhoff disease and Sandhoff disease using a bicistronic lentiviral vector encoding cDNA of HexAα-andβ-subunit genes separated by the nucleotide sequence of a P2A peptide(HEXA-HEXB).The functionality of the bicistronic construct containing the HEXA-HEXB genetic cassette was analyzed in a culture of HEK293T cells and human umbilical cord blood mononuclear cells(hUCBMCs).Our results showed that the enzymatic activity of HexA in the conditioned medium harvested from genetically modified HEK293T-HEXA-HEXB and hUCBMCs-HEXA-HEXB was increased by 23 and 8 times,respectively,compared with the conditioned medium of native *** blot analysis showed that hUCBMCs-HEXA-HEXB secreted both completely separated HEXA and HEXB proteins,and an uncleaved protein containing HEXA+HEXB linked by the P2A *** injection of genetically modified hUCBMCs-HEXA-HEXB to laboratory Wistar rats was carried out,and the HexA enzymatic activity in the blood plasma of experimental animals,as well as the number of live cells of immune system organs(spleen,thymus,bone marrow,lymph nodes)were determined.A significant increase in the enzymatic activity of HexA in the blood plasma of laboratory rats on days 6 and 9(by 2.5 and 3 times,respectively)after the administration of hUCBMCsHEXA-HEXB was *** the same time,the number of live cells in the studied organs remained ***,the functionality of the bicistronic genetic construct encoding cDNA of the HEXA and HEXB genes separated by the nucleotide sequence of the P2A peptide was shown in vitro and in *** hypothesize that due to the natural ability of hUCBMCs to overcome biological barriers,such a strategy can rest

关键词： bicistronic vector cell-mediated gene therapy GM2 gangliosidosis P2A peptide Sandhoff disease Tay-Sachs disease umbilical cord blood mononuclear cells β-hexosaminidase