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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

Methods for the use of the best Russian innovations in forest fire detection and suppression

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Journal of Forestry Research 2021年第6期32卷 2255-2263页

作者： alexander A.Martynyuk vera A.Savchenkova Nikolay A.Korshunov Roman v.Kotelnikov All-Russian Research Institute of Silviculture and Mechanization of Forestry(ARRISMF) Institutskaya str.15PushkinoMoscow regionRussia141202

This paper addresses the final stage of the study concerning the practical use of the best Russian methods,technologies and means for detecting and extinguishing forest fires in *** general,the work is aimed at increasing the effectiveness of the forest fire protection system by improving the methodological and technical support for the use of the best new *** the course of the study,analytical methods have been applied,tested and used in silviculture,while developing and improving the regulatory legal and methodological *** on the selection of research directions in the preliminary stages of work,analysis of the current state,use,and the development forecast of the most effective and promising technologies was carried *** addition,for detecting,controlling and extinguishing forest fires,including a comparative analysis of their economic efficiency,methods for practical use of the best Russian innovations was developed.A significant number of new developments have accumulated which,for a number of reasons,have not been *** into account the current state and dynamics of these promising methods,technologies,means of detecting and extinguishing forest fires,this study substantiates the development forecast of these promising innovations and their *** structure includes general provisions,concepts and terminology,regulatory support,the procedure for assessing the feasibility and effectiveness of the innovations,as well as a list of recommended documents for studying the use of technology for detecting,controlling and extinguishing forest *** methods will help meet modern requirements for the protection of forests from wildfires,and present an algorithm for their implementation in practice.

关键词： Forest protection Fire suppression Wildfire Efficacy

Zr4+/F– co-doped TiO2（anatase） as high performance anode material for lithium-ion battery

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Progress in Natural Science:Materials International 2018年第5期28卷 542-547页

作者： Denis P.Opra Sergey v.Gnedenkov Sergey L.Sinebryukhov Elena I.voit alexander A.Sokolov alexander Yu.Ustinov veniamin v.Zheleznov Institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University

Zr4+and F–co-doped TiO2with the formula of Ti0.97Zr0.03O1.98F0.02was facilely synthesized by a sol-gel template *** crystal structure,morphology,composition,surface area,and conductivity were characterized by Raman spectroscopy,energy-dispersive X-ray analysis,scanning electron microscopy,Brunauer-Emmett-Teller measurements,X-ray photoelectron spectroscopy,and electrochemical impedance *** results demonstrate that Zr4+and F–homogeneously incorporated into TiO2,forming solid solution with an anatase ***0.97Zr0.03O1.98F0.02shows outstanding electrochemical properties as Li-ion battery anode in comparison with *** particular,upon 35-fold cycling at 1C-rate Zr4+/F–co-doped TiO2delivers a reversible capacity of 163 mAh g–1,whereas Zr4+-doped TiO2gives only 34 mA h g–***,Zr4+/F–co-doped TiO2retains a capacity of 138 mA h g–1during cycling even at 10 *** enhance performance originates from improved conductivity of Zr4+/F–co-doped TiO2material through generation of Ti3+（serving as electron donors）into the crystal lattice and,possibly,due to F-doping blocked the anode surface from attack of HF formed as electrolyte decomposition product.

关键词： Li-ion batteries TiO2(anatase) Anode Co-doping Sol-gel template Process Electrochemical performance

A 96-antenna radioheliograph

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Research in Astronomy and Astrophysics 2014年第7期14卷 864-868页

作者： Sergey v.Lesovoi alexander T.Altyntsev Eugene F.Ivanov Alexey v.Gubin Institute of Solar-Terrestrial Physics

Here we briefly present some design approaches for a multifrequency 96-antenna radioheliograph. The configuration of the array antenna, transmission lines and digital receivers is the main focus of this work. The radioheliograph is a T-shaped centrally condensed radiointerferometer operating in the frequency range 4–8 *** justification for the choice of such a configuration is discussed. The signals from antennas are transmitted to a workroom by analog optical links. The dynamic range and phase errors of the microwave-over-optical signal are considered. The signals after downconverting are processed by digital receivers for delay tracking and fringe stopping. The required step of delay tracking and data rates are considered. Two 3-bit data streams（I and Q） are transmitted to a correlator with the transceivers embedded in Field Programmed Gate Array chips and with PCI Express cables.

关键词： telescopes -- instrumentation: interferometers -- Sun: radio radiation

Physiological significance of oxidative stress and its role in adaptation of the human body to deleterious factors

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Frontiers in Biology 2018年第1期13卷 19-27页

作者： vadim v. Davydov alexander v. Shestopalov Evgenya R. Grabovetskaya Chair of biochemistry and molecular biology Pirogov Russian National Research Medical University Moscow 117997 Russia Chair of biochemistry v.N. Karazin Kharkov National University Ukraine Kharkov 61077 Ukraine

BACKGROUND： Oxidative stress is an extremely widespread condition manifested in an increased rate of free-radical processes and accumulation of reactive oxygen species （ROS） in the tissues. It appears in different physiologic states and pathological processes accompanied by stimulation of the sympathetic adrenal system or tissue hypoxia or under stress. However, until now, there is still no clarity on the issue of the significance of oxidative stress in the development of adaptation processes in the organism. OBJECTIvE： In the present work we will review the most recent finding about physiologic role of oxidative stress and its participation in adaptation of an organism to effect of different adverse factors. METHODS： A systematic literature search was performed using the Pubmed search engine. Studies published over past 18 years, i.e. between 1998 and 2015 were considered for review. Followed keywords were used：＂oxidative stress,＂＂free radical oxidation,＂＂ROS,＂＂endogenous aldehydes,＂＂adaptation.＂ RESULTS： The article cites arguments supporting the notion that oxidative stress serves as a nonspecific link in the adaptation of the human body to the effects of injurious factors. Oxidative stress exerts regulatory effects by changing the redox state of the cell. Oxidative stress affects on various intracellular proteins containing cysteine residues, e.g., enzymes, chaperones, and transcription factors, etc. For this reason, the use of antioxidants for the treatment and prophylaxis of a wide range of diseases is not recommended. CONCLUSION： Further investigation is needed in this field. The most attention should be paid to careful experimental verification aimed at quantitative assessment of the ROS level in tissues under oxidative stress, as well as at the study of possibility of enhancing the catabolism of free radical oxidation carbonyl products in order to prevent tissue damage under oxidative stress.

关键词： oxidative stress free radical oxidation ROS adaptation endogenous aldehydes

Electrostatic Interaction-directed Construction of Hierarchical Nanostructured Carbon Composite with Dual Electrical Conductive Networks for Zinc-ion Hybrid Capacitors with Ultrastability

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Energy & Environmental Materials 2024年第1期7卷 184-192页

作者： Changyu Leng Zongbin Zhao Xuzhen Wang Yuliya v.Fedoseeva Lyubov G.Bulusheva alexander v.Okotrub Jian Xiao Jieshan Qiu State Key Lab of Fine Chemicals School of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical Engineering Dalian University of TechnologyDalian 116024China Nikolaev Institute of Inorganic Chemistry Siberian Branch of the Russian Academy of Sciences3 Acad.Lavrentiev Ave.Novosibirsk 630090Russia College of Chemical Engineering Beijing University of Chemical Technology Beijing 100029China

Metal-organic framework(MOF)-derived carbon composites have been considered as the promising materials for energy ***,the construction of MOF-based composites with highly controllable mode via the liquid-liquid synthesis method has a great challenge because of the simultaneous heterogeneous nucleation on substrates and the self-nucleation of individual MOF nanocrystals in the liquid ***,we report a bidirectional electrostatic generated self-assembly strategy to achieve the precisely controlled coatings of single-layer nanoscale MOFs on a range of substrates,including carbon nanotubes(CNTs),graphene oxide(GO),MXene,layered double hydroxides(LDHs),MOFs,and SiO_(2).The obtained MOF-based nanostructured carbon composite exhibits the hierarchical porosity(v_(meso)/v_(micro)∶2.4),ultrahigh N content of 12.4 at.%and"dual electrical conductive networks."The assembled aqueous zinc-ion hybrid capacitor(ZIC)with the prepared nanocarbon composite as a cathode shows a high specific capacitance of 236 F g^(-1)at 0.5 A g^(-1),great rate performance of 98 F g^(-1)at 100 A g^(-1),and especially,an ultralong cycling stability up to 230000 cycles with the capacitance retention of 90.1%.This work develops a repeatable and general method for the controlled construction of MOF coatings on various functional substrates and further fabricates carbon composites for ZICs with ultrastability.

关键词： carbon composite electrostatic interaction metal-organic framework coating self-assembly zinc-ion hybrid capacitor

Regulation of TRP-like muscarinic cation current in gastrointestinal smooth muscle with special reference to PLC/InsP3/Ca2+ system

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Acta Pharmacologica Sinica 2006年第7期27卷 833-842页

作者： alexander v ZHOLOS Department of Physiology Queen’s University Belfast UK

Acetylcholine,the main enteric excitatory neuromuscular transmitter,evokes mem-brane depolarization and contraction of gastrointestinal smooth muscle cells byactivating G protein-coupled muscarinic *** the cholinergic exci-tation is generally underlined by the multiplicity of ion channel effects,the pri-mary event appears to be the opening of cation-selective channels;among themthe 60 pS channel has been recently identified as the main target for the acetylcho-line action in gastrointestinal *** evoked cation current,termed mICAT,causes either an oscillatory or a more sustained membrane depolarization response,which in turn leads to increases of the open probability of voltage-gated Ca2+channels,thus providing Ca2+entry in parallel with Ca2+release for intracellularCa2+concentration rise and *** recent years there have been severalsignificant developments in our understanding of the signaling processes under-lying *** have revealed important synergistic interactionsbetween M2and M3receptor subtypes,single channel mechanisms,and the in-volvement of TRPC-encoded proteins as essential components of native musca-rinic cation *** review summarizes these recent findings and in par-ticular discusses the roles of the phospholipase C/InsP3/intracellular Ca2+releasesystem in the mICATphysiological regulation.

关键词： smooth muscle muscarinic receptor G protein phospholipase C InsP3 calcium TRP cation channel

Ecological and habitat ranges of orchids in the northernmost regions of their distribution areas:A case study from Ural Mountains,Russia

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Plant Diversity 2023年第2期45卷 211-218页

作者： Irina A.Kirillova Yuriy A.Dubrovskiy Svetlana v.Degteva alexander B.Novakovskiy Institute of Biology of Komi Science Centre of the Ural Branch of the Russian Academy of Sciences 28 Kommunisticheskaya St.167982SyktyvkarKomi RepublicRussia

The Orchidaceae,which is one of the most interesting families of angiosperms,contains a large number of rare *** their acknowledged importance,little attention has been paid to the study of orchids distributed in northern *** this study,we determined the syntaxonomical diversity and ecological parameters of orchid habitats in two of Europe's largest protected areas,the Pechoro-Ilychsky Reserve and the Yugyd va National Park(northeastern European Russia),and then compared our findings to those in other parts of orchid distribution *** this purpose,we studied 345 descriptions of plant communities(releves) containing species from Orchidaceae and defined habitat parameters using Ellenberg indicator values with the community weight mean approach,nonmetric multidimensional scaling(NMS),and relative niche *** found that orchids were distributed in eight habitat types and 97 plant *** largest number of orchid species is found in forest *** of the orchid species under study occur in the mires and rock habitats with open *** orchids consistently occur in areas disturbed by human *** addition,our study indicates that the main drivers of orchid distribution across the vegetation types are light and soil *** analysis of the ecological parameters of orchid habitats indicates that some orchid species can be classified as habitat specialists that are confined to a relatively narrow ecological niche in the Urals(e.g.,Goodyera repens,Cypripedium guttatum and Dactylorhiza maculata).Several other species(*** cordata and Dactylorhiza fuchsia) grow under diverse ecological parameters.

关键词： Orchidaceae Plant communities Nature protected areas Community weight mean Illumination Moisture

Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,virginia,USA

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Journal of Forestry Research 2020年第4期31卷 1255-1270页

作者： Lauren v.Austin alexander Silvis W.Mark Ford Karen E.Powers Department of Fish and Wildlife Conservation Virginia TechBlacksburgVA 24061USA Resource Environmental Solutions WarrentonVA 20187USA U.S.Geological Survey Virginia Cooperative Fish and Wildlife Research UnitBlacksburgVA 24061USA Biology Department Radford UniversityRadfordVA 24141USA

Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat *** wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn *** examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),virginia,*** was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)***,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy *** results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians.

关键词： Appalachian mountains Bats False-positive occupancy Prescribed fire Wildfire