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3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology,reflection seismics,magnetotellurics and density modelling:Geodynamic speculations

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Geoscience Frontiers 2020年第3期11卷 999-1023页

作者： Michael v.Mints victor N.Glaznev Olga M.Muravina Elena Yu Sokolova Geological Institute RASMoscowRussia voronezh State University VoronezhRussia Schmidt Institute of Physics of the Earth RASMoscowRussia All-Russian Research Geological Oil Institute MoscowRussia

A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is *** model is based on the combination of data from geological mapping and reflection seismic studies,along profiles 1-EU,4 B,FIRE-1-2 a-2 and FIRE-3-3 a,and uses results of magnetotelluric soundings in southern Finland and northern Karelia.A seismogeological model of the crust and crust-mantle boundary is compared with a model of subhorizontal velocity-density layering of the *** TTG-type crust of the Palaeoarchaean and Mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts,at least some of which are *** structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intracontinental settings modified by a strong collisional compression at the end of the *** insights into structure,origin and evolution of the Svecofennian Orogen are *** accretionary complex is characterized by inclined tectonic layering:the tectonic sheets,~15 km thick,are composed of volcanic-sedimentary rocks,including electro-conductive graphite-bearing sedimentary rocks,and electro-resistive granitoids,which plunge monotonously and consecutively *** reaching the level of the lower crust,the tectonic sheets of the accretionary complex lose their distinct *** the seismic reflection pattern they are replaced by a uniform acoustically translucent medium,where separate sheets can only be traced *** crust-mantle boundary bears a diffuse character:the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent *** the effect of endogenic heat flow,the accretionary complex underwent high-temperatu

关键词： Reflection seismics Magnetotellurics Svecofennian accretionary Orogen Svecofennian Ocean 3D crustal model velocity-density layering

SnO_(2)-ZnO nanocomposite thin films:The influence of structure,composition and crystallinity on optical and electrophysical properties

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Journal of Advanced Dielectrics 2021年第5期11卷 25-32页

作者： E.M.Bayan v.v.petrov M.G.volkova v.Yu Storozhenko A.v.Chernyshev Faculty of Chemistry Southern Federal University Rostov-on-DonRussia Institute of Nanotechnologies Electronicsand Equipment Engineering Southern Federal UniversityTaganrogRussia Research Institute of Physical and Organic Chemistr Southern Federal University Rostov-on-DonRussia

SnO_(2)-ZnO thin films consisting of nanoscale crystallites were obtained on glass and silicon substrates by solid-phase low-temperature *** synthesized materials were studied by XRD and SEM methods,electrophysical and optical properties were evaluated,as well as the band gap was *** was shown that regardless of the phase composition all films were optically transparent in the visible range(310-1000 nm).The nanocrystallites’minimum size,the highest activation energy of the conductivity and the smallest band gap calculated for indirect transitions were shown for a thin film 50SnO_(2)-*** was assumed that the band gap decreasing might be attributed to the existence of surface electric fields with a strength higher than 4×10^(5)v/cm.

关键词： Zinc tin oxide crystal structure optical property thin films semiconductors nanocomposite

v2551 Cyg:a pulsating star with enigmatic peculiarities

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Research in Astronomy and Astrophysics 2017年第7期17卷 57-66页

作者： Diana P.Kjurkchieva velimir A.Popov Dragomir v.Marchev Kenneth T.Menzies Nikola I.petrov Department of Physics Shumen University IRIDA Observatory Rozhen NAO Tigh Speuran Observatory Institute of Astronomy and NAO Bulgarian Academy of Sciences

Intensive photometric and spectral observations of the variable star v2551 Cyg are *** light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing binary. The period and amplitude of the light curve, the amplitudes of color changes and the radial velocity curve of v2551 Cyg are similar to those of a high-amplitude δ Scuti variable. The target seems to pulsate with the fundamental mode. However, v2551 Cyg exhibits several important peculiarities：（i） the decreasing branch of its light curve is steeper than the increasing one;（ii） the radial velocity curve has a flat section in the phase range 0.7-1.2 and short increase of the negative radial velocity at phase 0.7;（iii） the rotational velocity is quite big for a HADS star;（iv） the Fourier coefficients of v2551 Cyg are quite different from those of HADS stars. The target classification is difficult due to these peculiarities.

关键词： stars variables delta Scuti - stars variables RR Lyrae - stars individual (v2551 Cyg)

Sex and season explain spleen weight variation in the Egyptian mongoose

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Current Zoology 2019年第1期65卷 11-20页

作者： victor BANDEIRA Emilio virgos Alexandre AZEvEDO Joao Carvalho Monica v. CUNHA Carlos Fonseca Dartment of Biology Centro de Estudos do Ambiente e do Mar (CESAM) University of Aveiro Campus Universitario de Santiago Aveiro 3810-193 Portugal Departamento de Biologia Geologia Fisica y Qufmica Inorganica Area Biodiversidad y Conservacion Escuela Superior de Ciencias Experimentales y Tecnologia (ESCET) Universidad Rey Juan Carlos c/Tulipan s/n Mostoles Madrid E-28933 Spain Leibniz Institute for Zoo and Wildlife Research Alfred-Kowalke-Straβe 17 Berlin 10315 Germany Instituto de Ciencias Biomedicas Abel Salazar R. Jorge de Viterbo Ferreira 228 Porto 4050-313 Portugal Instituto Nacional de Investigaqao Agraria e veterinaria (INIAv) IP-National Institute for Agrarian and Veterinary Research Rua dos Lagidos Lugar da Madalena Vairao 4485-655 Portugal cE3c-Centre for Ecology Evolution and Environmental Changes Faculdade de Ciencias Universidade de Lisboa Lisboa 1749-016 Portugal BiolSI-Biosystems & Integrative Sciences Institute Faculdade de Ciencias Universidade de Lisboa Lisboa 1749-016 Portugal Wildlife Ecology & Health group (WE&H) and Servei d'Ecopatologia de Fauna Salvatge (SEFaS) Departament de Medicina i Cirurgia Animals Universitat Autonoma de Barcelona 08193-Bellaterra Barcelona Spain

The Egyptia n mon goose (Herpestes ichneumon Linn aeus, 1758) is a medium-sized car nivore that experienced remarkable geographic expansion over the last 3 decades in the Iberian Peninsula. In this study, we investigated the association of species-related and abiotic factors with spleen weight (as a proxy for immunocompete nee) in the species. We assessed the relationship of body con dition, sex, age, seas on, and envir onmental conditi ons with splee n weight established for 508 hunted specimens. Our results indicate that the effects of sex and season outweigh those of all other variables, including body condition. Spleen weight is higher in males than in females, and heavier spleens are more likely to be found in spring, coinciding with the highest period of investment in reproduction due to mating, gestation, birth, and lactation. Coupled with the absence of an effect of body condition, our findi ngs suggest that splee n weight variation in this species is mostly influe need by lifehistory traits linked to reproduction, rather than overall energy availability, winter immunoenhancement, or energy partitioning effects, and prompt further research focusing on this topic.

关键词： body condition carnivore Herpestes ichneumon Iberian Peninsula mongoose spleen weight

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNOvA G S KURSKIEv E O KISELEv N N BAKHAREv v K GUSEv N A KHROMOv S YU MEDvEDEv v B MIINAEv I v MIROSHNIKOv M I PATROv Yu v petrov N v SAKHAROv A D SLADKOMEDOvA P B SHCHEGOLEv v v SOLOKHA v A TOKAREv S YU TOLSTYAKOv E A TUKHMENEvA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

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中国北方盆地大规模铀成矿作用:地层篇

地质学报 2024年第7期98卷 1953-1976页

作者：程银行金若时 Michel CUNEY v.A.petrov 苗培森中国地质调查局天津地质调查中心(华北地质科技创新中心) 天津300170 中国地质调查局铀矿地质重点实验室天津300170 法国洛林大学资源学院法国NancyF54500 俄罗斯科学院矿床地质、岩石学、矿物学和地球化学研究所俄罗斯Moscow119017

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米... 详细信息

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米铀矿岩芯钻探成果,通过典型矿床赋矿层沉积学、地球化学等对比研究,系统分析了北方盆地侏罗系、白垩系、新近系等赋矿层形成的沉积环境、物质组成等,进一步明确了制约成矿流体运移、铀矿物沉淀的赋矿层条件。结果显示:①北方盆地自侏罗纪以来,发育了Ⅰ中侏罗世—晚侏罗世早期(Bathonian-Oxfordian)、Ⅱ早白垩世早期(valanginian)、Ⅲ早白垩世晚期(Aptian)、Ⅳ晚白垩世早期(Cenomanian)、Ⅴ晚白垩世晚期—早古近纪(Campanian-Thanetian)、Ⅵ早新近纪(Aquitanian-Burdigalian)和Ⅶ晚新近纪(ZancleanPiacenzian)7期红层,与下伏富还原性组分的黑色层构成了典型的对偶沉积建造,为北方盆地大规模成矿奠定了赋矿层基础。②地球化学指标显示:红层中Fe^(2+)/Fe^(3+)比值介于0.29~1.47(n=78),黑层Fe^(2+)/Fe^(3+)比值介于0.57~53.96(n=223),赋矿层Fe^(2+)/Fe^(3+)比值介于1.00~26.45(n=52)。赋矿层、黑层Fe^(2+)/Fe^(3+)比值一般大于1,以发育黄铁矿、炭屑、油斑为特征,为相对较还原的环境。红层Fe^(2+)/Fe^(3+)比值一般小于1,以发育钙质结核为特征,为相对较强氧化的环境。③总有机碳含量显示红层为0~0.16%(n=107),含矿层为0.01%~2.65%(n=137),黑层为0.01%~2.66%(n=339),含矿层总有机碳含量略低于黑层,与铀矿的富集沉淀有密切关系。④砂岩型铀矿体呈“板状”或“楔状”产出于黑层顶部的灰色、灰绿色砂岩和细砂岩,甚至泥岩,红层为含氧含铀流体的运移通道,黑层为含氧含铀流体的富集沉淀的化学屏障。因此,北方盆地红层和黑层对偶沉积、旋回充填是大规模铀成矿必要的地层条件,这些认识打破常规思维,“红黑”旋回叠加导致了北方盆地多层成矿的现象,矿体一般呈板状就位于红层和黑层的过渡带,这对深入理解砂岩型铀矿成矿环境、成矿规律及成矿机理等工作和勘查工作部署具有重要实践意义。

关键词：北方中—新生代盆地砂岩型铀矿大规模成矿沉积环境赋矿层

Design of broadband terahertz vector and vortex beams: I. Review of materials and components

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Light(Advanced Manufacturing) 2022年第4期3卷 126-144页

作者： Nikolay v.petrov Bogdan Sokolenko Maksim S.Kulya Andrei Gorodetsky Aleksey v.Chernykh Digital and Display Holography Laboratory ITMO UniversitySt.Petersburg 197101Russia v.I.vernadsky Crimean Federal University Simferopol 295007Russia School of Physics and Astronomy University of BirminghamBirmingham B152TTUK

In this paper,we review the existing approaches for vortex and vector beam shaping and generation in the terahertz frequency *** particular focus of this review is on the possibility of homogeneous topological charge formation in the ultra-wide spectral interval inherent to ultrashort terahertz *** review the available materials and components,analyse proposed and potentially possible solutions for broadband terahertz vortex and vector beam shaping,compare all developed approaches,and put forward a unified concept for constructing passive shapers of such beams from the existing component base.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography Total internal reflection Metasurface THz liquid crystals Geometric phase

Design of broadband terahertz vector and vortex beams: II. Holographic assessment

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Light(Advanced Manufacturing) 2022年第4期3卷 14-26页

In this paper,we demonstrate the capabilities of the terahertz pulse time-domain holography in visualisation,simulation,and assessment of broadband THz vortex beam formation dynamics upon its shaping by elements of beam converter,and further propagation and *** adding Jones matrix formalism to describe broadband optical elements,we highlight the differences in the spatio-spectral and spatio-temporal structure of the formed vortex and vector beams dependence on the modulator used and visualise their modal *** influence of diffraction field structure from each element in the broadband vortex modulator is revealed in numerical simulation and the formed beams are analysed against the simplified Laguerre-Gaussian beam model.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography

Observation of nonlinear disclination states

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Light(Science & Applications) 2023年第9期12卷 1818-1829页

作者： Boquan Ren Antonina A.Arkhipova Yiqi Zhang Yaroslav v.Kartashov Hongguang Wang Sergei A.Zhuravitskii Nikolay N.Skryabin Ivan v.Dyakonov Alexander A.Kalinkin Sergei P.Kulik victor O.Kompanets Sergey v.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at *** of these topological states is consistent with the bulk-disclination correspondence principle,and is due to the filling anomaly that results in fractional charges to the boundary unit *** far,topological disclination states were observed only in the linear regime,while the interplay between nonlinearity and topology in the systems with disclinations has been never studied *** report here on the experimental observation of the nonlinear photonic disclination states in waveguide arrays with pentagonal or heptagonal disclination cores inscribed in transparent optical medium using the fs-laser writing *** transition between nontopological and topological phases in such structures is controlled by the Kekulédistortion coefficient r with topological phase hosting simultaneously disclination states at the inner disclination core and spatially separated from them corner-I,corner-II,and extended edge states at the outer edge of the *** show that the robust nonlinear disclination states bifurcate from their linear counterparts and that location of their propagation constants in the gap and,hence,their spatial localization can be controlled by their *** disclination states can be efficiently excited by Gaussian input beams,but only if they are focused into the waveguides belonging to the disclination core,where such topological states *** results open new prospects for investigation of nonlinear effects in topological systems with disclinations and are relevant for different areas of science,including Bose-Einstein and polariton condensates,where potentials with the disclinations can be created.

关键词： structure topological nonlinear