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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

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冻土水分迁移机理研究:评述与展望

冰川冻土 2023年第2期45卷 588-598页

作者：温智邓友生冯文杰 aleksandr zhirkov 张莲海高樯中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 Melnikov Permafrost Institute Siberian BranchRussian Academy of SciencesYakutsk 117997Russia

土冻结过程中的水分迁移、积聚是冻害形成的关键环节,至今仍是冻土物理学研究的前沿和重要课题。二十世纪七八十年代冻土水分迁移研究黄金时代以后,长期未有经典理论和科学认知的重大突破,冻土水分迁移中涉及的许多机理性问题和关键瓶... 详细信息

土冻结过程中的水分迁移、积聚是冻害形成的关键环节,至今仍是冻土物理学研究的前沿和重要课题。二十世纪七八十年代冻土水分迁移研究黄金时代以后,长期未有经典理论和科学认知的重大突破,冻土水分迁移中涉及的许多机理性问题和关键瓶颈难题至今仍不能准确回答,尚存在很多争议和认识上的不足,现有研究成果在实际工程中的应用并不令人完全满意。因其性质的易变性、微观性和突变性,冻结相变区(冻结缘)仍是冻土水热输运研究中的一个“黑箱”。研究评述了冻土水分迁移驱动力与迁移过程相关研究的发展历程、主要研究进展与现状;分析了孔隙水压力、土水势驱动冻土水分迁移的物理原理和基本规律,综述了孔隙水压力、土水势的理论表征与试验测试等方面的最新进展、认知现状与主要科学问题;分析了三种流行的冻土水分迁移理论,即毛细水迁移理论、薄膜水迁移理论和水汽迁移理论;总结了制约冻土水分迁移科学认知突破的关键瓶颈难题,展望了未来研究的重点和方向。认为未来的研究应加强仪器设备的改进、研发与新技术引入,重点关注冻土水分迁移驱动力的物理本质和精准监测,强化冻土水分迁移的微观过程及机制认识,需从非平衡态热力学的视角关注热质输运与冰-水相变过程,注重工程化冻土多物理场模型的开发与自主开源计算平台的构建。本文旨在系统梳理冻土水分迁移机理的研究历史与现状,总结概述冻土水分迁移研究在新思想、新理论、新方法和新技术等方面的最新研究动态,凝练指出亟待解决的前沿科学问题和未来研究的重点,促进冻土热质输运基础理论的发展与完善,更好地服务于寒区工程冻融灾害和环境问题的解决。

关键词：冻土水分迁移毛细水薄膜水克拉伯龙方程

Predicting impact strength of perforated targets using artificial neural networks trained on FEM-generated datasets

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Defence Technology（防务技术） 2024年第2期32卷 32-44页

作者： Nikita Kazarinov aleksandr Khvorov Saint Petersburg State University Saint Petersburg 199034Russia Higher School of Economics Saint Petersburg 190121Russia

The paper considers application of artificial neural networks(ANNs)for fast numerical evaluation of a residual impactor velocity for a family of perforated PMMA(Polymethylmethacrylate)*** ANN models were trained using sets of numerical results on impact of PMMA plates obtained via dynamic FEM coupled with incubation time fracture *** developed approach makes it possible to evaluate the impact strength of a particular target configuration without complicated FEM calculations which require considerable computational ***,it is shown that the ANN models are able to predict results for the configurations which cannot be processed using the developed FEM routine due to numerical instabilities and errors:the trained neural network uses information from successful computations to obtain results for the problematic cases.A simple static problem of a perforated plate deformation is discussed prior to the impact problem and preferable ANN architectures are presented for both *** insight into the perforation pattern optimization using a genetic algorithm coupled with the ANN is also made and optimized perforation patterns which theoretically enhance the target impact strength are constructed.

关键词： Machine learning Impact Dynamic fracture FEM Mesh distortion Optimization

尔丹盾爱尔康地台第四纪沉积物的热物理性质(英文)

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黑龙江大学工程学报 2014年第3期5卷 215-219页

作者： Rev I.Gavriliev Anatolii R.Kirillin aleksandr F.zhirkov 俄罗斯科学院西伯利亚分院麦尔尼科夫冻土研究所

对于爱尔康地垒第四纪沉积物的地热性的有效值和物理参数而言，其事实上不仅是构成沉积物的活性层，而更有助于评价爱尔康煤矿冻土区的基础设施和工程。爱尔康地垒沉积物的厚度从几米到十几米，这以下的事实相符，在第四纪大地构造发展... 详细信息

对于爱尔康地垒第四纪沉积物的地热性的有效值和物理参数而言，其事实上不仅是构成沉积物的活性层，而更有助于评价爱尔康煤矿冻土区的基础设施和工程。爱尔康地垒沉积物的厚度从几米到十几米，这以下的事实相符，在第四纪大地构造发展阶段，爱尔康地垒遭受了弧形块的不同的振幅和强度的不断膨胀。根据从初始到第四纪沉积残留物选出渣油，洪积层，崩积和冲积层。他们是由花岗岩片麻岩组成的。在岩石材料较多的斜坡上的渣油和冲积层，其由砂和粉砂组成结合砾石和粗砾石。在超过10种类型的土壤元素工程地质剖面上，其热导率为0.50～2 W/（M· K），其热导率如下：堆积层为1.51 W/（M· K）、洪积层为1.32 W/（M· K）、冲积层为1.50 W /（M· K）。对于给出的爱尔康矿区工程地质段的主要元素物理和热物理参数的平均值和极限值而言，由所呈现的元素的组合构成。在德林达河段呈现爱尔康岩性剖面特征，在科纳-苏拉河头，沿着Uzky支流和1号营矿所设计的道路也呈现出这一特征。所有类型的矿床成因和位置的地形形式：分水岭，斜坡和山谷都包括在内。获得爱尔康地垒第四纪沉积的整个厚度的热物理性质和物理参数的有效值，是以表的形式汇总，该有效值有助于预测基础设施和周边炼油设施，并为热分析的爱尔康铀矿床的开发提供了依据。

关键词：地垒第四纪沉积物活性层工程地质记录导热系数比热容

Experimental Study of Liquid Metal Flow for the Development of a Contact-Less Control Technique

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1553-1564页

作者： aleksandr Poluyanov Ilya Kolesnichenko Laboratory of Technological Hydrodynamics Institute of Continuous Media Mechanics of the Ural Branch of Russian Academy of Science(ICMM UB RAS)Perm614018Russia

The article presents an experimental study on the flow of an eutectic gallium alloy in a cylindrical cell,which is placed in an alternating magnetic *** magnetic field is generated by a coil connected to an alternating current *** coil is located at a fixed height in such a way that its plane is perpendicular to the gravity vector,which in turn is parallel to the axis of the *** position of the cylinder can vary in height with respect to the *** forced flow of the considered electrically conductive liquid is generated due to the action of the localized electromagnetic *** is assumed that under the action of the alternating magnetic field,the liquid is heated uniformly,and the resulting heat is quickly absorbed by the forced flow,so that liquid free convection can be *** experiment is carried out using an ultrasonic Doppler *** transducer is installed in the axially located cylinder sluice and the other transducer is placed in the near-wall *** to the results,a velocity profile,corresponding to a two-tori flow pattern can be hardly obtained in the low frequency range of the power ***,this is possible in the high frequency *** average velocity profiles depend essentially on the location of the coil relative to the *** spectral analysis of velocity signals shows that the amplitude of the velocity pulsations is comparable to the average value of the flow *** experimental results and their verification through comparison with numerical calculations are intended to support the development of new methods for reducing the intensity of vortex flows during the electromagnetic separation of impurities through an electromagnetic induction mechanism(able to produce an electromotive force that displaces particles).

关键词： Ultrasonic doppler velocimeter electrically conductive medium azimuthal pinch experiment in liquid metal magnetohydrodynamics

A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints

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Defence Technology（防务技术） 2024年第4期34卷 78-133页

作者： Tushar Sonar Mikhail Ivanov Evgeny Trofimov aleksandr Tingaev Ilsiya Suleymanova Department of Welding Engineering Institution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia Department of Materials Science Physical and Chemical Properties of MaterialsInstitution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia

The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion *** alloys are manufactured by the equal mixing or larger proportions of five or more alloying *** exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of *** state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA *** HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs *** similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial ***,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi *** state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.

关键词： High entropy alloys Solid state welding Microstructure Mechanical properties

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow

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High Voltage 2024年第1期9卷 127-136页

作者： Shixin Zhao Xingbao Lyu aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev aleksandr Chirtsov Gennadii Shabanov Zhongxiang Zhou School of Physics Harbin Institute of TechnologyHarbinChina Physics Department Saint Petersburg Electrotechnical University“LETI”St.PetersburgRussia Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology HarbinChina Physics Department St.Petersburg State UniversitySt.PetersburgRussia Konstantinov Petersburg Nuclear Physics Institute National Research Centre“Kurchatov Institute”GatchinaRussia

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball ***,crucial aspects concerning the plasma components of the resulting afterglow remain ***,the measurement of the electron density,a critical parameter,has not been fully achieved thus *** this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and *** antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived *** findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive *** the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two *** measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles.

关键词： holds luminous electrolytic

Comparing the Structural Parameters of the Milky Way to Other Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第3期24卷 10-28页

作者： Jacob A.Guerrette aleksandr V.Mosenkov Dallin Spencer Zacory D.Shakespear Department of Physics and AstronomyN283 ESCBrigham Young University ProvoUT 84602USA

The structural parameters of a galaxy can be used to gain insight into its formation and evolution *** this paper,we strive to compare the Milky Way’s structural parameters to other,primarily edge-on,spiral galaxies in order to determine how our Galaxy measures up to the Local *** our comparison,we use the galaxy structural parameters gathered from a variety of literature sources in the optical and near-infrared wave *** compare the scale length,scale height,and disk flatness for both the thin and thick disks,the thick-to-thin disk mass ratio,the bulge-to-total luminosity ratio,and the mean pitch angle of the Milky Way’s spiral arms to those in other *** conclude that many of the Milky Way’s structural parameters are largely ordinary and typical of spiral galaxies in the Local Universe,though the Galaxy’s thick disk appears to be appreciably thinner and less extended than expected from zoom-in cosmological simulations of Milky Way-mass galaxies with a significant contribution of galaxy mergers involving satellite galaxies.

关键词： Galaxy disk-galaxies fundamental parameters-Galaxy structure

Agglomeration of coal and polyethylene mixtures during fixed‑bed co‑gasification

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International Journal of Coal Science & Technology 2024年第2期11卷 91-100页

作者： Igor G.Donskoy aleksandr N.Kozlov Maksim V.Penzik Denis A.Svishchev Lu Ding Melentiev Energy Systems Institute Russian Federation130 Lermontova StreetIrkutskRussia 664033 East China University of Science and Technology 130 Meilong RoadShanghai 200237China

The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory *** work aims to study the agglomeration process during the heating and oxidation of the *** measurement results(gas composition,pressure drop)provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel *** have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates,in which the molten polymer acts as a *** form as a result of interfacial interactions between components and filtration flow *** hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11,indicating the formation of stable hydrocarbon compounds on the carbon *** conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene.

关键词： Coal Polyethylene Gasification Combustion Agglomeration