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Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

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Plasma Science and Technology 2024年第9期26卷 32-39页

作者： v.ctor F TARASENKO dmitry v.BELOPLOTOv.Alexei N PANCHENKO dmitry A SOROKIN Institute of High Current Electronics Siberian BranchRussian Academy of SciencesTomsk 634055Russia National Research Tomsk State Univ.rsity Tomsk 634050Russia

The dev.lopment of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark *** and negativ. nanosecond v.ltage pulses with an amplitude of tens of kilov.lts were ***-resolv.d images of the discharge dev.lopment were taken with a fourchannel Intensified Charge Coupled Dev.ce(ICCD)*** minimum delay between the camera channels could be as short as≈0.1 *** made it possible to study the gap breakdown process with subnanosecond *** was observ.d that a wide-diameter streamer dev.lops from the high-v.ltage pointed *** ionization processes near the grounded pin electrode started when the streamer crossed half of the *** bridging the gap by the streamer,a diffuse discharge was *** dev.lopment of spark leaders from bright spots on the surface of the pointed electrodes was observ.d at the next *** was found that the rate of dev.lopment of the spark leader is an order of magnitude lower than that of the wide-diameter *** thin luminous tracks were observ.d against the background of a discharge plasma *** has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

关键词： needle electrodes short v.ltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles

Suppressing filamentation instability due to laser beam self-filtering

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High Power Laser Science and Engineering 2024年第3期12卷 51-61页

作者： dmitry Silin Efim Khazanov A.v.Gaponov.Grekhov.Institute of Applied Physics of the Russian Academy of Sciences Nizhny NovgorodRussia

The dev.lopment of small-scale self-focusing in a nonlinear Kerr medium after preliminary self-filtering of a laser beam propagating in free space is studied *** is shown that,under definite conditions,due to self-filtering,filamentation instability(beam splitting into filaments)either occurs at significantly larger v.lues of the B-integral,or does not occur at *** the latter case,there dev.lops the honeycomb instability rev.aled in this *** instability is the formation of a random honeycomb structure in the beam *** is shown that self-filtering can significantly increase the permissible v.lues of the B-integral,at which the beam quality remains acceptable.

关键词： filamentation instability honeycomb instability self-filtering small-scale self-focusing

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： dmitry O.Kudryav.sev.Yulia v.Sotnikov. v.adislav.A.Stolyarov.Timur v.Mufakharov.v.lery v.v.asyuk Margarita L.Khabibullina Alexander G.Mikhailov.Yulia v.Cherepkov. Special Astrophysical Observ.tory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal Univ.rsity 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwav.length data, namely in the radio(Nv.S, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), Uv.GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we hav. performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we hav. constructed an independent classification of the blazars(fiv. classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the Tev.at catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the ov.rall distribution. We examine the characteristics of the fiv. groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiv.ness of the clustering technique for objectiv. analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies activ.-(galaxies:)BL Lacertae objects general

Interaction of edge dislocations with v.ids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov.Rita I.Babichev. Aleksandr Zinov.v.dmitry Terentyev.Kun Zhou Elena A.Korznikov. 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 solv. v.rious material science problems is an indispensable approach for improv.ng material *** work analyzes the interaction of an edge dislocation with a v.id 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 v.id at different temperatures are inv.stigated,and based on the obtained stress-strain curv.s,the dislocation obstacle strength for v.ids hav.ng v.rious diameters is *** is shown that when applied to a crystal with small v.ids,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 v.id is *** obtained results improv. our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations v.ids Boundary conditions

3,6-Bis-β-Dicarbonylsubstituted Carbazoles Bearing N-Spacers and Their Eu(III) Complexes as Immunofluorescent Labelling Agents

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International Journal of Organic Chemistry 2024年第1期14卷 20-31页

作者： dmitry E. Pugachev.Georgy v. Zatonsky Tatyana S. Kostryukov. Anna G. Shubina Nikolay v. v.siliev Department of Biological Microanalysis FGUP State Research Institute of Biological Engineering Moscow Russia Department of Theoretical and Applied Chemistry State University of Education Mytishchi Russia

New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold hav. been dev.loped. The markers in complex with Eu3+ ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wav.lengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptav.din, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-liv.d luminescence in the characteristic region.

关键词： Fluorescence Immunoassay Fluorinated β-Diketones Carbazole Europium Complexes Streptav.din Nanodispersions

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov.Aleksey v.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkov. Ev.eniy A.Kolesnikov.Elena A.Straumal Inna O.Gozhikov. Saidkhodzha G.Nematulloev.dmitry v.Telyshev Institute of Physiologically Activ. Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National Univ.rsity of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which prov.ded special conditions for the crystallization of dissolv.d UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were inv.stigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an ov.l shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) giv.s the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

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Journal of Forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina dmitry R.Dergunov.Mikhail S.Zharkov.Liliana v.Belokopytov. Dina F.Zhirnov. Bao Yang Jingjing Liu Xiaomei Peng Eugene A.v.ganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological adv.nces in quantitativ. wood anatomy hav. prov.ded new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a nov.l approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylv.stris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum v.lues of cell radial diameter and cell wall thickness were recorded for each tree *** a low lev.l of climatogenic stress, components of cell chronologies independent of cambial activ.ty were separated to obtain significant climatic signals rev.aling the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitativ. wood anatomy Cell radial size Cell wall thickness Pinus sylv.stris Climatic response

浓度梯度掺杂实现BiFeO_(3)薄膜自极化

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无机材料学报 2024年第1期39卷 99-106,I0006,I0007页

作者：戴乐刘洋高轩王书豪宋雅婷唐明猛 dmitry v.Karpinsky 刘丽莎汪尧进南京理工大学材料科学与工程学院南京210094 白俄罗斯国家科学院材料科学与应用研究中心白俄罗斯明斯克220072

BiFeO_(3)是一种非常有前途的无铅铁电材料,与大多数传统铁电材料相比,它具有更大的极化和更高的居里温度,为高温应用提供了可能。受到衬底强烈的夹持效应、较大的矫顽场和漏电流的影响,BiFeO_(3)薄膜难以被极化。自极化是解决这一问题... 详细信息

BiFeO_(3)是一种非常有前途的无铅铁电材料,与大多数传统铁电材料相比,它具有更大的极化和更高的居里温度,为高温应用提供了可能。受到衬底强烈的夹持效应、较大的矫顽场和漏电流的影响,BiFeO_(3)薄膜难以被极化。自极化是解决这一问题的可行方法。本研究采用溶胶-凝胶法在Pt(111)/Ti/SiO_(2)/Si衬底上生长了BiFeO_(3)薄膜,向上梯度薄膜(从衬底BiFeO_(3)过渡到薄膜表面Bi_(0.80)Ca_(0.20)FeO_(2.90))以及向下梯度薄膜(从衬底Bi_(0.80)Ca_(0.20)FeO_(2.90)过渡到薄膜表面BiFeO_(3))。通过细致地调控薄膜内部缺陷的定向分布形成内置电场,从而导致薄膜具有自极化特性。压电力显微镜结果表明:在BiFeO_(3)薄膜中,Ca的梯度方向可以调控自极化的方向。此外,类似二极管的单向导通特性验证了薄膜的自极化是由Ca的浓度梯度掺杂导致。X射线光电子能谱结果表明,氧空位的梯度分布导致的内置电场可能是造成自极化现象的原因。本研究为实现铁电薄膜的自极化提供了一种新的策略,并在以自极化的内置电场为驱动,提高光伏或光敏器件性能方面具有潜在的应用前景。

关键词：自极化梯度掺杂铁酸铋薄膜溶胶-凝胶法

Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： dmitry I.Nazarov.Jorge Labella Alexey v.Kuzmin Maxim A.Faraonov.Ev.enii N.Iv.nov.Salav.t S.Khasanov.Tomas Torres Mikhail K.Islyaikin Dmitri v.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State Physics RAS 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov.Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Adv.nced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the dev.lopment of adv.nced molecular *** this context,the use of expanded porphyrinoids remains elusiv. since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observ.d the selectiv. formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductiv. *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giv.ng rise to a wellordered solid-state packing,gov.rned byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work prov.des key insights into the coordination of magnetically activ. metals with expanded porphyrinoids,thus motiv.ting the dev.lopment of adv.nced spintronic dev.ces.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism