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Features of sampling stream sediments of large river valleys under cryolithogenesis conditions in the Balygychan-sugoy trough,North-East of Russia

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Acta Geochimica 2024年第4期43卷 638-660页

作者： artem s.Makshakov Raisa G.Kravtsova A.P.Vinogradov Institute of Geochemistry Siberian Branch of the Russian Academy of SciencesFavorskiy Str 1AIrkutskRussia 664033

Comprehensive research has been implemented to raise the efficiency of the geochemical survey of stream sediments(sss)that formed under the cryolithogenesis *** authors analysed the composition,structure and specific features of the formation of exogenous anomalous geochemical fields(AGFs)identified through sss of large river valleys of IV *** our case,these were the valleys of Maly Ken,Ken and Tap *** rivers are located in the central and southern parts of the Balygychan-sugoy trough enclosed in the Magadan region,North-East of *** authors proposed a new technique to sample loose alluvium of sss in the large river valleys along the *** profiles were located across the *** AGFs of Au,Ag,Pb,Zn,sn,Bi,Mo and W were *** between elements have been *** elements are the main indicator elements of Au-Ag,Ag-Pb,sn-Ag,Mo-W and sn-W mineralization occurring on the sites under *** results obtained were compared with the results of geochemical surveys of *** is concluded that the AGFs recognized along the profiles reflect the composition and structure of eroded and drained ore zones,uncover completely and precisely the pattern of element distribution in loose sediments of large water *** alluvium fractionseems to be most significant in a practical sense,as it concentrated numerous ore *** of this fraction in the river valleys of IV order does not cause any difficulty,for this kind of material is *** developed technique of alluvium sampling within large river valleys is efficient in searching for diverse mineralization at all stages of prognostic *** is applicable for geochemical survey of sss performed at different scales both in the North-East of Russia,as well as other regions with similar climatic conditions,where the sss are formed under the cryolithogenesis conditions.

关键词： stream sediments Large river valleys Geochemical fields Mineralization Indicator elements Geochemical survey

Longitudinal dependence of the forecast accuracy of the ionospheric total electron content in the equatorial zone

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Geodesy and Geodynamics 2024年第5期15卷 528-541页

作者： artem Kharakhashyan Olga Maltseva Institute for Physics Southern Federal University344090Russia

The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are *** also applies to the prediction of the ionospheric total electron content(TEC),which neural network methods have recently been widely ***,the results are mainly presented for a limited set of *** paper examines the longitudinal dependence of the TEC forecast accuracy in the equatorial *** this case,the methods are used that provided the best accuracy on three meridians:European(30°E),southeastern(110°E)and American(75°W).Results for the stations considered are analyzed as a function of longitude using the Jet Propulsion Laboratory Global Ionosphere Map(JPL GIM)for *** results are for 2 h ahead and 24 h ahead *** was found that in this case,based on the metric values,three groups of architectures can be *** first group included long short-term memory(LsTM),gated recurrent unit(GRU),and temporal convolutional networks(TCN)models as a part of unidirectional deep learning models;the second group is based on the recurrent models from the first group,which were supplemented with a bidirectional algorithm,increasing the TEC forecasting accuracy by 2-3 *** third group,which includes the bidirectional TCN architecture(BiTCN),provided the highest *** this architecture,according to data obtained for 9 equatorial stations,practical independence of the TEC prediction accuracy from longitude was observed under the following metrics(Mean Absolute Error MAE,Root Mean square Error RMsE,Mean Absolute Percentage Error MAPE):MAE(2 h)is 0.2 TECU approximately;MAE(24 h)is 0.4 TECU approximately;RMsE(2 h)is less than 0.5 TECU except Niue station(RMsE(2 h)is 1 TECU approximately);RMsE(24 h)is in the range of 1.0-1.7 TECU;MAPE(2 h)station,MAPE(24 h)his result was confirmed by data from additional 5 stations that formed latitudinal chains in the

关键词： Ionosphere Total electron content Forecasting BiGRU BiLsTM BiTCN Temporal convolution

Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer science 2024年第4期42卷 492-500页

作者： Laura A.Rishina Yury V.Kissin svetlana s.Lalayan artem A.Antonov Vadim G.Krasheninnikov Alexander A.Gulin N.N.semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and Chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2h5)2Cl and Mg(C4h9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2h5)2Cl-Mg(C4h9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

stretchable on-skin touchless screen sensor enabled by ionic hydrogel

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Nano Research 2024年第5期17卷 4462-4470页

作者： Tianxing Feng Dan Ling Chaoyue Li Wentao Zheng shichuan Zhang Chang Li artem Emel’yanov Alexander s.Pozdnyakov Lijun Lu Yanchao Mao Key Laboratory of Materials Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China A.E.Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russian Federation

screen sensors are the most commonly used human-machine interfaces in our everyday life,which have been extensively applied in personal electronics like *** screen sensors are attracting growing interest due to their distinct advantages of high interaction freedom,comfortability,and hand ***,the material compositions of current touchless screen sensors are rigid and fragile,hardly meeting the needs of wearable and stretchable on-skin electronics ***,these touchless screen sensors are also restricted by high power consumption,limited gesture types of recognition,and the requirement of light ***,we report a stretchable on-skin touchless screen sensor(OTss)enabled by an ionic hydrogel-based triboelectric nanogenerator(TENG).Compared with current touchless screen sensors,the OTss is stretchable,self-powered,and competent to recognize diverse gestures by making use of charges naturally carried on fingers without the need of sufficient light *** on-skin noncontact screen operating system is further demonstrated on the basis of the OTss,which could unlock a cellphone interface in touchless operation mode on the human *** work for the first time introduces the on-skin touchless concept to screen sensors and offers a direction to develop new-generation screen sensors for future cellphones and personal electronics.

关键词： human-machine interface stretchable ionic hydrogel triboelectric nanogenerator self-powered sensor

Terahertz high-sensitivity sIs mixer based on Nb–AlN–NbN hybrid superconducting tunnel junctions

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Chinese Physics B 2024年第5期33卷 681-686页

作者：刘博梁刘冬姚明金骏达王争李婧史生才 artem Chekushkin Michael Fominsky Lyudmila Filippenko Valery Koshelets Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China school of Astronomy and space sciences University of Science and Technology of ChinaHefei 230026China Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of SciencesMoscow 125009Russia

The terahertz band,a unique segment of the electromagnetic spectrum,is crucial for observing the cold,dark universe and plays a pivotal role in cutting-edge scientific research,including the study of cosmic environments that support life and imaging black ***-sensitivity superconductor–insulator–superconductor(sIs)mixers are essential detectors for terahertz astronomical telescopes and interferometric *** to the commonly used classical Nb/AlO_(x)/Nb superconducting tunnel junction,the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current *** makes it particularly promising for the development of ultra-wideband,high-sensitivity coherent detectors or mixers in various scientific research *** this paper,we present a superconducting sIs mixer based on Nb/AlN/NbN parallel-connected twin junctions(PCTJ),which has a bandwidth extending up to490 Ghz–720 *** best achieved double-sideband(DsB)noise temperature(sensitivity)is below three times the quantum noise level.

关键词： sIs mixer terahertz gap voltage critical current density hybrid superconducting tunnel junction

Optimizing Average Electric Power During the Charging of Lithium-Ion Batteries Through the Taguchi Method

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Transactions of Tianjin University 2024年第2期30卷 152-166页

作者： Mohd h.s.Alrashdan Department of Electrical Engineering Al-Hussein Bin Talal UniversityMaan 71110Jordan

In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17

关键词： Lithium-ion batteries Average electric power during charging Taguchi method COMsOL Multiphysics software C rate L27 orthogonal array

hetero-integrated high-peak-optical-power laser source (940 nm) for time-of-flight sensors

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Chinese Optics Letters 2024年第7期22卷 81-85页

作者： sergey Olegovich slipchenko Aleksandr Aleksandrovich Podoskin Ilia Vasil'evich shushkanov Marina Gennad'evna Rastegaeva artem Eduardovich Rizaev Matvey Igorevich Kondratov artem Evgen'evich Grishin Nikita Aleksandrovich Pikhtin Timur Anatol'evich Bagaev Maxim Anatol'evich Ladugin Aleksandr Anatol'evich Marmalyuk Vladimir Aleksandrovich simakov Ioffe Institut Russian Academy of SciencesSt.Petersburg 194021Russia Open Joint-stock Company M.F.stel’makh Polyus Research Institute Moscow 117342Russia RUDN University Moscow 117198Russia

The generation of high-power laser pulses using a compact hetero-integrated assembly based on a semiconductor laser with a dual-element composite 2μm×100μm aperture and a compact heterothyristor switch is *** achieved peak optical power was 33 W with a pulse duration of 3 ns at a thyristor operating voltage of 55 *** leading edge of the laser pulse turn-on was 50 ps to a power level of 24.7 W,and the turn-on delay between the elements of the composite aperture was 160 ps.

关键词： hetero-integrated assembly semiconductor lasers thyristor switches LIDAR gain-switching mode laser heterostructure

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铝合金焊接凝固裂纹及焊材抗裂性的研究进展

机械工程学报 2024年第12期60卷 207-219页

作者：王浩刘坤李洁余文明吴红 OKULOV artem 江苏科技大学材料科学与工程学院镇江212100 中国船舶重工集团应急预警与救援装备股份有限公司武汉430223 俄罗斯科学院乌拉尔分院叶卡捷琳堡620077俄罗斯

铝合金的高质量焊接在轻量化制造中发挥着重要作用,但铝合金的焊接凝固裂纹敏感性较高,在焊接过程中极易出现开裂,严重影响铝合金焊接结构质量和安全可靠性。焊接凝固裂纹产生于高温熔池后方的糊状区,裂纹萌生及扩展是一个受多种因素影... 详细信息

铝合金的高质量焊接在轻量化制造中发挥着重要作用,但铝合金的焊接凝固裂纹敏感性较高,在焊接过程中极易出现开裂,严重影响铝合金焊接结构质量和安全可靠性。焊接凝固裂纹产生于高温熔池后方的糊状区,裂纹萌生及扩展是一个受多种因素影响的高温复杂过程,糊状区的高温冶金行为尤为关键。全面分析铝合金焊接凝固裂纹及焊材抗裂性的研究现状,对于深刻理解铝合金焊接凝固裂纹机理及抑制具有重要的指导意义。综述铝合金焊接凝固裂纹机理、凝固裂纹判据、敏感性测试、凝固裂纹的影响因素以及焊材抗裂性等方面的研究进展。针对目前存在的问题进行了总结,并对未来研究方向进行了展望,为铝合金凝固裂纹冶金机理的深入研究及裂纹抑制提供有价值的参考。

关键词：铝合金焊接冶金凝固裂纹糊状区抗裂性

A Comprehensive Review on Charging Topologies and Power Electronic Converter solutions for Electric Vehicles

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Journal of Modern Power systems and Clean Energy 2024年第3期12卷 675-694页

作者： Abdelfatah Ali hossam h.h.Mousa Mostafa F.shaaban Maher A.Azzouz Ahmed s.A.Awad the Department of Electrical Engineering American University of Sharjah26666 SharjahUnited Arab Emirates the Department of Electrical Engineering South Valley University83523 QenaEgypt the Department of Electrical and Computer Engineering University of WindsorWindsorON N9B 3P4 Canada Electrical Engineering Department Qatar UniversityDoha 2713Qatar Department of Electrical and Computer Engineering Sultan Qaboos UniversityMuscat123Oman

Electric vehicles(EVs)are becoming more popular worldwide due to environmental concerns,fuel security,and price *** performance of EVs relies on the energy stored in their batteries,which can be charged using either AC(slow)or DC(fast)***,EVs can also be used as mobile power storage devices using vehicle-to-grid(V2G)*** electronic converters(PECs)have a constructive role in EV applications,both in charging EVs and in ***,this paper comprehensively investigates the state of the art of EV charging topologies and PEC solutions for EV *** examines PECs from the point of view of their classifications,configurations,control approaches,and future research prospects and their impacts on power *** can be classified into various topologies:DC-DC converters,AC-DC converters,DC-AC converters,and AC-AC *** address the limitations of traditional DC-DC converters such as switching losses,size,and high-electromagnetic interference(EMI),resonant converters and multiport converters are being used in high-voltage EV ***,power-train converters have been modified for high-efficiency and reliability in EV *** paper offers an overview of charging topologies,PECs,challenges with solutions,and future trends in the field of the EV charging station applications.

关键词： Charging station charging topology electric vehicle power electronic converter vehicle-to-grid