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

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)<1%except Darwin station,MAPE(24 h)<2%.This 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

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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 fraction<0.25 mm seems 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

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Technological achievements in the fabrication of tubular-designed protonic ceramic electrochemical cells

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Materials Futures 2024年第4期3卷 71-106页

作者： Maria A Gordeeva artem P Tarutin Nikolai A Danilov Dmitry A Medvedev Laboratory of Electrochemical Devices Based on Solid Oxide Proton Electrolytes Institute of High-Temperature Electrochemistry620066 EkaterinburgRussia Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia

Protonic ceramic electrochemical cells provide an excellent basis for the advancement of high-temperature solid oxide devices,offering potential solutions to a range of challenges in the hydrogen energy and carbon capture *** facilitated ionic transport in proton-conducting electrolytes enables these cells to operate at temperatures 100◦C–500◦C lower than those of conventional solid oxide cells with known zirconia *** a result,promising performances have been reported for various types of proton ceramic electrochemical ***,these advancements have been demonstrated only at the laboratory scale,whereas their ZrO2-based counterparts have already been *** review presents an overview of the fundamental and applied aspects related to the fabrication of tubular protonic ceramic electrochemical cells and their subsequent characterization as hydrogen permeation membranes,hydrogen pumps,hydrogen sensors,fuel cells,electrolysis cells,and electrochemical reactors.A specific focus is placed on the technological aspects of the tube preparations derived from the original powder sources as well as the dimensional characteristics of the tubes,which serve as an indicator of ***,this review serves as a starting point for the development and scaling of protonic ceramic electrochemical cells,with the potential for large-scale production.

关键词： electrochemistry energy conversion hydrogen proton transport perovskite solid oxide cells scaling

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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

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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

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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

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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

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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

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Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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Nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-García Herme G.Baldovi artem A.Babaryk Antonio Rodríguez-Diéguez Sergio Navalón Yolanda Pérez Hermenegildo García Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain Departamento de Química Universitat Politècnica de València46022 ValènciaSpain Departamento Química Inorgánica Universidad de Granada1807GranadaSpain Departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IEF-15,IEF-16,and IEF-17(IEF stands for IMDEA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IEF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IEF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

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ChatGPT: Application in Chemistry Education and Challenges

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Journal of Computer and Communications 2024年第3期12卷 196-206页

作者： Vladimir L. Kodkin Ekaterina V. artem’eva Power Engineering Faculty South Ural State University Chelyabinsk Russia Department of Chemistry Institute of Natural Sciences South Ural State University Chelyabinsk Russia

The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ability to process and analyze large amounts of data, create personalized training systems, and offer problem-solving recommendations. The paper delves into practical applications, showcasing how ChatGPT can be utilised to augment chemistry learning. It provides examples of using ChatGPT for creating tests, generating multiple-choice questions, and studying chemistry in general. Concerns are voiced about the ethical and societal impact of AI development. In conclusion, it explores the exciting potential of AI to tackle challenges that may exceed human capabilities alone, paving the way for further exploration and collaboration between humans and intelligent machines.

关键词： ChatGPT 3.5 Artificial Intelligence AI for Education Computer-Based Learning

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