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Low-altitude geophysical magnetic prospecting based on multirotor UAv as a promising replacement for traditional ground survey

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Geo-Spatial Information Science 2018年第1期21卷 67-74页

作者： Alexander v.Parshin vladimir A.Morozov Anton v.Blinov Alexey N.Kosterev Alexander E.Budyak Ore Geology Lab Vinogradov Institute of Geochemistry SB RASIrkutskRussia SibGISTech LLC MarkovaRussia Geoinformatics Lab Irkutsk National Research Technical UniversityIrkutskRussia

The prospects for expanding the mineral resource base in many countries are linked with the exploration of stranded sites localized at unexplored areas with complex natural and landscape conditions that make any ground survey,including magnetic prospecting,difficult and *** current level of geology requires high-precision and large-scale data at the first stages of geological *** 2012,technologies of aeromagnetic surveying with unmanned aircraft vehicles(UAv)enter the market,but most of them are based on big fixed-wing UAv and do not allow to substantially increase the level of survey granularity compared with traditional aerial *** increase the scale of survey,it is necessary to reduce the altitude and speed of flight,for which the authors develop the methodical and technical solutions described in this *** obtain data at altitudes of 5 m above the terrain even in a rugged relief,we created heavy multirotor UAvs that are stable in flight and may be used in a wide range of environmental conditions(even a moderate snowfall),and develop a special software to generate flight missions on the basis of digital elevation models.A UAv has special design to reduce magnetic interference of the flight platform;the magnetic sensor is hung below the *** technology was conducted in a considerable amount of magnetic surveys in the mountainous regions of East Siberia between 2014 and *** results of the comparison between airborne and ground surveys are presented,which show that the sensitivity of the developed system in conjunction with low-altitude measurements can cover any geologically significant anomalies of the magnetic *** unmanned survey is cheaper and more productive;the multirotor-based technologies may largely replace traditional ground magnetic exploration in scales of 1:10,000−1:1000.

关键词： Unmanned aircraft vehicles(UAv) magnetic survey geophysical prospecting airborne geophysics unmanned aerial system(UAS)

The Biologic Active Zones(BAZ) in the White,Greenland,and Labrabor Seas and Its Climatological Modification:Comparative Study by Using Satellite and In-situ Data

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地学前缘 2009年第S1期16卷 120-121页

作者： Smirnova Alexandra vladimir v.Melentyev Melentyev vladimir Vasilievsky Island

The authors of this work have made an attempt to research a habitat of three existing populations of Greenland seal and conditions of biologically active zones(BAZ) located,accordingly,in White, Greenland and Labrador *** seal is an ice-associated sea mammal,and climate warming can be a decisive factor for its *** the researches of changes of ice state parameters of subarctic water areas are an urgent problem

关键词： biologically active zones satellite microwave sounding

Multi-scale polarisation phenomena

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Light(Science & Applications) 2016年第1期5卷 810-818页

作者： vladimir Kalashnikov Sergey v Sergeyev Gunnar Jacobsen Sergei Popov Sergei K Turitsyn AIPT Aston UniversityBirminghamWest Midlands B47ETUK Acreo Electrum 236SE-16440KistaSweden Royal Institute of Technology(KTH) SE-1640StockholmSweden

Multi-scale methods that separate different time or spatial scales are among the most powerful techniques in physics,especially in applications that study nonlinear systems with *** the time scales(noise and perturbation)are of the same order,the scales separation becomes ***,the multi-scale approach has to be modified to characterise a variety of noise-induced ***,based on stochastic modelling and analytical study,we demonstrate in terms of the fluctuation-induced phenomena and Hurst R/S analysis metrics that the matching scales of random birefringence and pump–signal states of polarisation interaction in a fibre Raman amplifier results in a new random birefringence-mediated phenomenon,which is similar to stochastic *** observed phenomenon,apart from the fundamental interest,provides a base for advancing multi-scale methods with application to different coupled nonlinear systems ranging from lasers(multimode,mode-locked,random,etc.)to nanostructures(light-mediated conformation of molecules and chemical reactions,Brownian motors,etc.).

关键词： fibre Raman amplifier multi-scale methods polarisation stochastic calculations

Ultra-thin, planar, Babinet-inverted plasmonic metalenses

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Light(Science & Applications) 2013年第1期2卷 170-175页

作者： Xingjie Ni Satoshi Ishii Alexander v Kildishev vladimir M Shalaev School of Electrical and Computer Engineering and Birck Nanotechnology Center Purdue UniversityWest LafayetteIN 47907USA

We experimentally demonstrate the focusing of visible light with ultra-thin,planar metasurfaces made of concentrically perforated,30-nm-thick gold *** perforated nano-voids—Babinet-inverted(complementary)nano-antennas—create discrete phase shifts and form a desired wavefront of cross-polarized,scattered *** signal-to-noise ratio in our complementary nano-antenna design is at least one order of magnitude higher than in previous metallic nano-antenna *** first study our proof-of-concept‘metalens’with extremely strong focusing ability:focusing at a distance of only 2.5 mm is achieved experimentally with a 4-mm-diameter lens for light at a wavelength of 676 *** then extend our work with one of these‘metalenses’and achieve a wavelength-controllable focal *** characterization of the lens confirms that switching the incident wavelength from 676 to 476 nm changes the focal length from 7 to 10 mm,which opens up new opportunities for tuning and spatially separating light at different wavelengths within small,micrometer-scale *** the proposed designs can be embedded on-chip or at the end of an optical *** designs also all work for two orthogonal,linear polarizations of incident light.

关键词： metalens nano-antennas plasmonics wavefront shaping

Thermoelectric and electrical characteristics of SmS ceramic samples after exposure to a pulsed magnetic field

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Journal of Rare Earths 2022年第11期40卷 1778-1784,I0004页

作者： Ivan volchkov Evgeniy Baskakov vladimir Strelov vladimir Kanevskii FSRC"Crystallography and Photonics"RAS Leninskiy Prospekt 59119333MoscowRussia

Samarium monosulfide(SmS)is a promising material for creating thermoelectric generators(TEG),gas sensors and strain *** the high values of the generated thermo electromotive force(TEMF)(α≈170-350μv/K),methods for increasing the efficiency of TEGs based on SmS are of considerable *** of these methods can be short-term effects of magnetic fields,including pulsed ones,on these *** action of a pulsed magnetic field(PMF)leading to an increase in TEMF(U)of SmS ceramic samples is *** that are not subjected to high frequency currents(HFC)annealing show an increase in UT of 44.54%-62.18%(from 11.9 to 17.2-19.3 mv).The conductivity(σ)of the samples is~22 Q/cm and is insensitive to short-term exposure to a *** that undergo HFC annealing show an increase in Uof 23.47%-41.31%(from 21.3 to 26.3-30.1 mv)after exposure to a *** conductivity of the samples is~15Ω^(-1)/cm and after a short exposure to the PMF is changing nonmo notonically,with an increase in the overall *** difference in the values of Uand a can be explained by presence of an ordered grain structure and a significant amount of the Sm_(2)O_(2)S phase in the samples subjected to HFC *** mechanisms of the observed changes are discussed.

关键词： Rare earths Thermoelectric Electric properties Magnetically induced changes Samarium monosulfide

Phase-matched third-harmonic generation via doubly resonant optical surface modes in 1D photonic crystals

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Light(Science & Applications) 2016年第1期5卷 424-429页

作者： valery N Konopsky Elena v Alieva Sergey Yu Alyatkin Alexey A Melnikov Sergey v Chekalin vladimir M Agranovich Institute of Spectroscopy Fizicheskaya5TroitskMoscow 142190Russia Moscow Institute of Physics and Technology Institutskiy per.9Dolgoprudny 141700Russia

Efficient nonlinear conversion requires that interacting optical waves maintain a consistent phase relationship when traveling in a medium despite its *** phase-matching,which is often used to compensate for the dispersion,is not applicable to optically isotropic nonlinear ***,we present a one-dimensional photonic crystal structure that allows the propagation of optical surface waves,both at the fundamental and third-harmonic frequencies,as an efficient medium for phasematched third-harmonic generation.A unique advantage of this structure is that the effective refractive indices for the surface waves are similar to the refractive index of air at both *** allows phase-matching between the first and third harmonics,and a visible collinear beam of the third harmonic is produced at the prism-coupled ***,these optical surface waves propagate over long distances even if a lossy nonlinear nanofilm is deposited onto the photonic crystal *** provide experimental results for third-harmonic generation at a wavelength of 410 nm for a bare dielectric Ta2O5/SiO2 multilayer structure and for the same structure coated with a 15-nm GaAs film.

关键词： nonlinear optics optical surface waves photonic crystals

Mafic, Ultramafic and Carbonatitic Dykes in the Southern Siberian Craton with Age of ca 1 Ga: Remnants of a New Large Igneous Province?

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 9-页

作者： Elena I.DEMONTEROvA Alexei v.ivanov valentina B.SAvELYEvA Institute of the Earth's Crust Siberian Branch of the Russian Academy of Sciences

virtual absence of igneous complexes with ages between1.8 Ga and 0.8 Ga in southern part of the Siberian Craton allowed to Galdkochub et al.(2010)to formulate a hypothesis of long magmatic *** reliable

关键词： area Ultramafic and Carbonatitic Dykes in the Southern Siberian Craton with Age of ca 1 Ga Mafic Remnants of a New Large Igneous Province

Studies of ultrasonic dehydration efficiency

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： vladimir N. KHMELEv Andrey v. SHALUNOv Roman v. BARSUKOv Denis S. ABRAMENKO Andrey N. LEBEDEv Biysk Technological Institute (Branch) Altai State Technical University

The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products.

关键词： Drying Ultrasound vibration system Drying chamber Processing (treatment) of agricultural products

Late Mesozoic topographic evolution of western Transbaikalia:Evidence for rapid geodynamic changes from the Mongol-Okhotsk collision to widespread rifting

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Geoscience Frontiers 2020年第5期11卷 1695-1709页

作者： A.v.Arzhannikova E.I.Demonterova M.Jolivet S.G.Arzhannikov E.A.Mikheeva A.v.ivanov v.B.Khubanov L.A.Pavlova Institute of the Earth’s Crust Russian Academy of SciencesSiberian BranchIrkutskRussia Laboratoire Geosciences Rennes CNRS-UMR6118Universite de RennesRennesFrance Geological Institute Russian Academy of SciencesSiberian BranchUlan-UdeRussia A.P.vinogradov Institute of Geochemistry Siberian Branch of the Russian Academy of SciencesIrkutskRussia

The Mesozoic geodynamic evolution of Transbaikalia has been largely controlled by the scissors-like closure of the Mongol-Okhotsk Ocean that separated Siberia from Mongolia-North China *** the oceanic closure,the tectonic evolution of that region was characterized by collisional uplift and subsequent extension that gave rise to the formation of metamorphic core *** complex tectonic setting prevailed simultaneously between 150 Ma and 110 Ma both in Transbaikalia,North Mongolia,and within the North China *** paleobotanical and paleontological data show that the oldest Mesozoic basins had formed in western Transbaikalia before the estimated age of extension *** no precise geochronological age is available for the onset of extension in *** Tugnuy Basin,as probably the oldest Mesozoic basin in western Transbaikalia,is a key obj ect to date the onset of extension and following changes in tectonic *** this study,U-Pb(LA-ICP-MS)dating of detrital zircons from three key Jurassic sediment formations of the Tugnuy Basin are used to identify the potential source areas of the sediments,understand the changes in sediment routing and provide insights on the topographic evolution of western *** results show several significant changes in tectonic regime after the closure of the Mongol-Okhotsk Ocean.A wide uplifted plateau formed during the closure of the Mongol-Okhotsk Ocean,determining the Early Jurassic drainage system reaching the Angaravitim batholith to the north and shedding sediments to the continental margin to the *** following collisional event at the end of the Early Jurassic led to the uplift of the collision zone,which partially inverted the drainage system toward the North.A strike-slip displacement induced by the oblique collision initiated some of the early Transbaikalian depressions,such as the Tugnuy Basin at about 168 Ma.A phase of basin inversion,marked by folding and ero

关键词： U–Pb detrital zircons dating Topographic evolution Mongol–Okhotsk collision Transbaikalia