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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

porphyrins,phthalocyanines,and related covalent-organic frameworks in the photochemical and electrochemical water splitting:A review

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particuology 2024年第7期90卷 236-265页

作者： Oxana v.Kharissova Yolanda peña Méndez Boris I.Kharisov aleksandr Lnikolaev Edith Luévano-Hipólito Lucy T.González Universidad Autónoma de nuevo León Ave.Universidad s/nSan Nicolás de los GarzaNuevo León66455Mexico Department of Chemistry Moscow State UniversityVorobievy HillsMoscowRussia COnACYT-Universidad Autónoma de nuevo León Facultad de Ingeniería Civil-Departamento de Ecomateriales y EnergíaCd.UniversitariaC.P.66455San Nicolás de los GarzaNLMexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo León 64890Mexico Tecnologico de Monterrey Centro del AguaMonterreyNuevo León 64890Mexico

In this review,the possibilities of photochemical and electrochemical water splitting(WS)using porphyrins,phthalocyanines,related macrocycles,and their metal complexes are *** efforts are being carried out in order to develop novel and cheap methods for water decomposition to generate inexhaustible greener energy sources(molecular hydrogen)instead of oil and *** processes of WS in heterogeneous and homogeneous media require novel photo-and electrocatalysts,in particular those on macrocycle basis.A high WS efficiency has been observed for porphyrins and phthalocyanines,showing their suitability both for HER and OER processes are available using these relative compounds for WS *** can be used in photocatalytic and electrocatalytic WS processes both in their free forms or as metal porphyrins/porphyrinates,mainly loaded on various inorganic materials,such as Au nps,C_(3)n_(4),Gap,KTaO_(3),Gap,and so on,as part of porphyrin-containing polymers or on electrode surface as modifying coatings,being sometimes better than commercial catalysts,such as pt/*** H2 evolution can be considerably depended on the shape of porphyrin particles;in particular,porphyrin nanowires can yield up to 20 times more H2 than its *** certain cases,both HER and OER can be driven in the same electrolyte using metal *** capacity of metal porphyrins to generate ROS(in particular,singlet oxygen 1O_(2))under ultrasonic treatment is known and can be successfully used for H_(2)O_(2) and O_(2) *** can be used in similar processes in free form or as composites with inorganic or organic counterparts,being immobilized on nanocarbons,metal oxides and salts,or simply dissolved in water acting in a homogeneous *** additional use of ultrasound can lead to better results due to the synergistic effect of the sonochemical treatment and ***-organic frameworks are also applied for WS purposes and are mainly based

关键词： porphyrins phthalocyanines COFs Water splitting photocatalysis Electrocatalysis

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim v.Grigoriev Anna v.Ruseikina Maxim S.Molokeev vladimir A.Chernyshev aleksandr S.aleksandrovsky Alexander S.Krylov Svetlana n.Krylova nikolai p.Shestakov Dmitriy A.velikanov Alexander A.Garmonov Alexey v.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,pr,nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 ev that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet n.Toksumakov Olga G.Matveeva Dmitriy v.Grudinin Kirill v.voronin Arslan Mazitov konstantin v.Kravtsov Alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.novikov Ivan Kruglov Davit A.Ghazaryan Andrey A.vyshnevyy Aleksey v.Arsenin valentyn S.volkov Kostya S.novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International physics Center(DIpC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. national Graphene Institute(nGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova Sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology Institute for Metals Superplasticity problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University Institute for nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University Institute of Mechanical Science problems of RAS Institute of Molecule and Crystal physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations voids Boundary conditions

nucleation of dislocations and twins in fcc nanocrystals: Dynamics of structural transformations

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Journal of Materials Science & Technology 2019年第1期35卷 201-206页

作者： aleksandr v.korchuganov.aleksandr n.tyumentsev.konstantin p.zolnikov.igor yu.litov.henko Dmitrij S.Kryzhevich Elazar Gutmanas Shouxin Li Zhongguang Wang Sergey G.psakhie Institute of Strength physics and Materials Science of Siberian Branch of Russian Academy of Sciences national Research Tomsk State University Technion–Israel Institute of Technology Shenyang national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials.

关键词： Lattice defects Dislocation nanotwin Atomic model Molecular dynamics simulations

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

pulsed THz radiation under ultrafast optical discharge of vacuum photodiode

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Frontiers of Optoelectronics 2024年第2期 100-113页

作者： aleksandr A.Ushakov Kseniia A.Mamaeva Leonid v.Seleznev Georgy E.Rizaev vladimir Bukin Timophey v.Dolmatov pavel A.Chizhov vladimir Bagdasarov Sergey v.Garnov prokhorov General physics Institute of the Russian Academy of Sciences physical Institute Russian Academy of Sciences Moscow Institute of physics and Technology Russian Institute for Scientific and Technical Information

In this paper, we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a vacuum photodiode. We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kv/cm external electric field for the photo-emitted electron acceleration. Measurements of terahertz pulses energy as a function of emitted charge density, incidence angle of optical radiation and applied electric field have been provided. Spectral and polarization characteristics of generated terahertz pulses have also been studied. The proposed semi-analytical model and simulations in COMSOL Multiphysics prove the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

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Changes in the growth of Scots pine(pinus sylvestris L.)stands in an urban environment in European Russia since 1862

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林业研究:英文版 2023年第5期34卷 1279-1287页

作者： aleksandr v.Lebedev Department of Agricultural Meliorations Forestry and Land OrganizationRussian State Agrarian University-Moscow Timiryazev Agricultural AcademyTimiryazevskaya49MoscowRussia 127434

A century and a half ago,in the European part of Russia(Moscow),forest scientists established the first long-term observations of forests,many of which are under observation to the present *** the twentieth century,climate changes and,due to industrial development,forest areas were under air *** on observations from 157 sites,this study shows that the growth and density of Scots pine(pinus sylvestris L.)have decreased by the end of the twentieth *** environment has changed,and the growth and development of plantations has *** yields(-34%stand volume)and their life expectancy(on average 50 years)have *** changes are critical for forestry and for the management of forests in urban *** to the decline in growth,ecosystem functions by urban forests has *** order to increase the sustainability of urban forests and the provision of ecosystem services,it is preferable to create multi-species stands with a complex structure.

关键词： Forest stand Scots pine Stand growth Urbanized environment Human footprint