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New family of single-component Ni catalysts for ethylene polymerization to high and ultrahigh molecular weight polyethylene

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Science China Chemistry 2020年第6期63卷 753-754页

作者： artem a.antonov Wen-Hua Sun Konstantin P.Bryliakov Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of SciencesBeijing 100049China

Since the milestone discovery of Ni(II)salicylaldiminate catalysts by Grubbs and co-workers[1],nickel(II)complexes with N,N-and N,O-donor ligands have strengthened their lead in the search for highly active platforms for olefins homo-and copolymerization with various co-monomers,including those with polar groups,to achieve polymers with precisely controlled microstructures[2,3].

关键词： discovery catalysts co-monomers

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 University

The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are discovered. This 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 meridians. This paper examines the longitudinal dependence of the TEC forecast accuracy in the equatorial zone. In 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 2015. These results are for 2 h ahead and 24 h ahead forecast. It was found that in this case, based on the metric values, three groups of architectures can be distinguished. The 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 times. The third group, which includes the bidirectional TCN architecture(BiTCN), provided the highest accuracy. For 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

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

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

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

Large-scale error-tolerant programmable interferometer fabricated by femtosecond laser writing

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Photonics Research 2024年第3期12卷 I0028-I0040页

作者： ILYA KONDRATYEV VERONIKA IVANOVA SUREN FLDZHYAN artem ARGENCHIEV NIKITA KOSTYUCHENKO SERGEY ZHURAVITSKII NIKOLAY SKRYABIN IVAN DYAKONOV MIKHAIL SAYGIN STANISLAV STRAUPE ALEXANDER KORNEEV SERGEI KULIK Quantum Technology Centre and Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Russian Quantum Center Moscow 121205Russia Laboratory of Quantum Engineering of Light South Ural State UniversityChelyabinsk 454080Russia

We introduce a programmable eight-port interferometer with the recently proposed error-tolerant architecture capable of performing a broad class of *** interferometer has been fabricated with femtosecond laser writing,and it is the largest programmable interferometer of this kind to *** have demonstrated its advantageous error tolerance by showing an operation in a broad wavelength range from 920 to 980 nm,which is particularly relevant for quantum photonics due to efficient photon sources existing in this wavelength *** work highlights the importance of developing novel architectures of programmable photonics for information processing.

关键词： interferometer laser femtosecond

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

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 86-90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 Sciences RUDN University Open Joint-Stock Company M.F.Stel'makh Polyus Research Institute

The generation of high-power laser pulses using a compact hetero-integrated assembly based on a semiconductor laser with a dual-element composite 2 μm × 100 μm aperture and a compact heterothyristor switch is demonstrated. The achieved peak optical power was 33 W with a pulse duration of 3 ns at a thyristor operating voltage of 55 V. The 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： Diode lasers High power lasers Laser arrays Laser sources Semiconductor lasers Vertical cavity surface emitting lasers

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

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