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Strain control of layer-resolved negative capacitance in superlattices

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npj Computational Materials 2020年第1期6卷 127-130页

作者： Raymond Walter sergey Prosandeev Charles Paillard L.Bellaiche Department of Physics and Institute for nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Department of Mathematical Sciences University of ArkansasFayettevilleAR 72701USA Identity Engineering Kinesso LLCConwayAR 72032USA Institute of Physics and Physics Department of Southern Federal University Rostov-na-Donu 344090Russia Laboratoire Structures Propriétés et Modélisation des SolidesCentraleSupélecUMR CNRS 8580UniversitéParis-Saclay91190 Gif-sur-YvetteFrance

negative capacitance in BaTiO_(3)/SrTiO_(3) superlattices is investigated by Monte Carlo simulations in an atomistic effective Hamiltonian model,using fluctuation formulas for responses to the local macroscopic field that incorporates depolarizing *** show that epitaxial strain can tune the negative capacitance of the BaTiO_(3) ferroelectric layer and the overall capacitance of the *** addition,we predict and explain an original switching of the negative capacitance from the BaTiO3 layer to the SrTiO_(3) layer at low temperatures for intermediate strains.

关键词： capacitance layer resolved

Pulsating magneto-dipole radiation of a quaking neutron star powered by energy of Alfvn seismic vibrations

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Research in Astronomy and Astrophysics 2011年第9期11卷 1085-1092页

作者： sergey Bastrukov Jun-Wei Yu Ren-Xin Xu Irina Molodtsova State Key Laboratory of nuclear Physics and Technology School of Physics Peking University Beijing 100871 China Joint Institute for nuclear Research 141980 Dubna Russia

We compute the characteristic parameters of the magneto-dipole radiation of a neutron star undergoing torsional seismic vibrations under the action of Lorentz restoring force about an axis of a dipolar magnetic field experiencing decay. After a brief outline of the general theoretical background of the model of a vibration-powered neutron star, we present numerical estimates of basic vibration and radiation characteristics, such as frequency, lifetime and luminosity, and investigate their time dependence on magnetic field decay. The presented analysis suggests that a gradual decrease in frequencies of pulsating high-energy emission detected from a handful of currently monitored AXP/SGR-like X-ray sources can be explained as being produced by the vibration-powered magneto-dipole radiation of quaking magnetars.

关键词： neutron stars -- torsion Alfv6n vibrations -- vibration powered radiation -- magnetic field decay -- magnetars

Investigation of radio pulsar emission features using power spectra

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Research in Astronomy and Astrophysics 2018年第8期18卷 63-70页

作者： Valery M.Malofeev sergey A.Tyul'bashev En.Lebedev Physical Institute of the Russian Academy of Sciences V.V.Vitkevich Pushchino Radio Astronomy ObservatoryPRAO ASC FIANPushchinoRussia

Since 2013, round-the-clock monitoring of the sky has been carried out simultaneously in 96 beams using a high-sensitivity radio telescope called the Large Phased Array （LPA） at the frequency 110.25 MHz. These observations are made under the program of interplanetary plasma investigation. The same data are used to search for pulsars by means of power spectra. To increase the sensitivity of the pulsar search, 500-600 power spectra corresponding to different days of observations are summed. In the integrated spectra of known pulsars, besides expected improvement in signal-to-noise （S/n） ratio for the frequency harmonics, some features are explored in this paper. We present the 27 strongest pulsars which are in a field with declination 21° - 42°. The observable details in the integrated power spectra are connected with the presence of pulsar periods of the second （P2） and third （P3） class, which have been identified. Empirical relations for calculating these periods are obtained. The value P2 is estimated for 26 pulsars, and for 15 sources it is made for the first time. The value P3 is estimated for 13 pulsars, among them these values are given for five sources for the first time.

关键词： pulsars general - pulsars

Modern problems of aircraft aerodynamics

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Advances in Aerodynamics 2019年第1期1卷 145-159页

作者： sergey L.Chernyshev sergey V.Lyapunov Andrey V.Wolkov Department of Aerodynamics Central Aerohydrodynamic Institute named after Prof.N.EZhukovsky(TsAGI)140180Zhukovsky str.1ZhukovskyRussia

The article represents the discussion of several separate directions of investigations,which are performed by TsAGI flight vehicles aerodynamics specialists at the *** are some major trends of classical layout of route aircraft and also peculiarities of some prospective flight *** there are some hypersonic vehicles aerodynamics questions examined along with problems of creation of civil supersonic transport *** is a description given for well-known and some newer methods of flow control for drag reduction.

关键词： Aircraft aerodynamics Hypersonic vehicles aerodynamics Civil supersonic transport aircraft Sonic boom

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振荡波导阵列中孤子的实验发现

科学通报:英文版 2023年第18期68卷 2017-2024,M0003页

作者： Antonina A.Arkhipova Yiqi Zhang Yaroslav V.Kartashov Sergei A.Zhuravitskii nikolay n.Skryabin Ivan V.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Victor O.Kompanets sergey V.Chekalin Victor n.Zadkov Institute of Spectroscopy Russian Academy of SciencesTroitsk 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Key Laboratory for Physical Electronics and Devices(Ministry of Education) School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另... 详细信息

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另一半周期内处于拓扑平庸相,它的边界上仍然支持源于拓扑的反常π模.本文通过在透明非线性光学材料中刻蚀出周期振荡的Su-Schrieffer-Heeger波导阵列,分别实验观测到了一维系统中位于边界和二维系统中位于角落的光学反常π模.同时,在弗洛凯频谱的禁带中,作者还证实了在高功率情况下一类分化自光学反常π模的新拓扑π孤子.本文报道的π孤子是强振荡的非线性弗洛凯态,它们的波形在每经过一个纵向周期后都可以精确地复现.不论是在一维还是在二维振荡波导阵列中,这类π孤子都是动态稳定的,它们的局域特性都由其功率决定.二维的结果还表明作者实现了弗洛凯光学高阶拓扑绝缘体.

关键词： Floquet topological insulators p states Edge solitons SSH model

Phylogeography of the common hamster(Cricetus cricetus):paleoclimatic reconstructions of Late Pleistocene colonization

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Integrative Zoology 2023年第3期18卷 581-599页

作者： natalia Yu.FEOKTISTOVA Ilya G.MESCHERSKY Georgy I.SHEnBROT Andrey Yu.PUZACHEnKO sergey I.MESCHERSKY Pavel L.BOGOMOLOV Alexey V.SUROV A.n.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Mitrani Department of Desert Ecology Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevMidreshet Ben-GurionIsrael Institute of Geography Russian Academy of SciencesMoscowRussia

InTRODUCTIOn Anthropogenic activities and associated factors such as climate change and habitat destruction are causing the ongoing sixth mass extinction on Earth,which is a major characteristic of the ***,these factors pose the most serious environmental threat to the existence of civilization because it is *** than 500 species of mammals were found to be on the brink of extinction and likely to be lost within 20 years(Ceballos et al.2020).One example is the common hamster Cricetus cricetus(Linnaeus,1758).In 2020,this species was classified as Critically Endangered across its global range by the IUCn Red List(Banaszek et al.2020).The protection status of the common hamster was elevated by 4 levels at once—from Least Concern to Critically *** the causes behind the dramatic decline of the species are not fully understood,one may suppose it stems from the negative impact of habitat degradation and even climate change(Banaszek et al.2020).

关键词： extinction suppose irreversible

Formation of Extended Covalently Bonded ni Porphyrin networks on the Au（lll） Surface

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纳米研究：英文版 2011年第4期4卷 376-384页

作者： sergey A. Krasnikov Catherine M. Doyle natalia n. Sergeeva Alexei B. Preobrajenski nikolay A.Vinogradov Yulia n. Sergeeva Alexei A. Zakharov Mathias O. Senge Attilio A. Cafolla School of Physical Sciences Dublin City University Glasnevin Dublin 9 Ireland Centre tbr Research on Adaptive nanostructures and nanodevices （CRAnn） School of Physics Trinity College Dublin Dublin 2 Ireland SFI Tetrapyrrole Laboratory School of Chemistry Trinity College Dublin Dublin 2 Ireland MAX-Lab Lund University Box 118 22100 Lund Sweden

The growth and ordering of {5,10,15,20-tetrakis(4-bromophenyl)porphyrinato}nickel(II) (niTBrPP) molecules on the Au(111) surface have been investigated using scanning tunnelling microscopy, X-ray absorption, core-level photoemission, and microbeam low-energy electron diffraction. When deposited onto the substrate at room temperature, the niTBrPP forms a well-ordered close-packed molecular layer in which the molecules have a flat orientation with the porphyrin macrocycle plane lying parallel to the substrate. Annealing of the niTBrPP layer on the Au(111) surface at 525 K leads to dissociation of bromine from the porphyrin followed by the formation of covalent bonds between the phenyl substituents of the porphyrin. This results in the formation of continuous covalently bonded porphyrin networks, which are stable up to 800 K and can be recovered after exposure to ambient conditions. By controlling the experimental conditions, a robust, extended porphyrin network can be prepared on the Au(111) surface that has many potential applications such as protective coatings, in sensing or as a host structure for molecules and clusters.

关键词：镍卟啉表面层 Au 网络扫描隧道显微镜 X射线吸收分子层电子衍射

Electromagnetic monitoring in the region of seismic activization (on the Gorny Altai (Russia) example)

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Geodesy and Geodynamics 2019年第6期10卷 460-470页

作者： nina n.nevedrova Aidisa M.Sanchaa Alexander E.Shalaginov sergey M.Babushkin Trofimuk Institute of Petroleum Geology and Geophysics of the Siberian Branch of the RAS Novosibirsk630090Russia Seismological Branch of Geophysical Survey of the Russian Academy of Sciences 3 Academician Koptug ave.Novosibirsk630090Russia

Based on the analysis of the field data of nonstationary electromagnetic soundings with different installations,the evolution of the stressed state of the geological massif in the epicentral region of the destructive 2003 M_w7.3 Chuya earthquake is investigated in the *** measurements by these methods were executed in a lot of regular points located at two sites of the western part of the Chuya basin of Gorny Altai(Russian Federation).The field works have been performed for 13 *** developed a measurement technique using data from the three Transient Electromagnetic Method(TEM)method settings for determination of the resistivity anisotropy *** of the field data is carried out based on the inverse problem solution,and further,taking into account the geological structure and seismological data,variations of true electrophysical characteristics of the cross-section(electrical resistivity and resistivity anisotropy coefficient)are *** to the TEM data acquired in the 1980 s,the geoelectric parameters of rocks in the period of low seismic activity were *** of the results of quantitative interpretation of the modern measurements(2004-2016)with those taken before the Chuya event allows tracing a change in the geoelectric parameters of the cross-section in the aftershock period,and on this basis tracking the evolution of the rock massif after the destructive seismic impact.

关键词： Transient electromagnetic Resistivity anisotropy coefficient Time-lapse survey Gorny Altai Chuya basin

A Review of Arctic-Subarctic Ocean Linkages: Past Changes, Mechanisms, and Future Projections

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Ocean-Land-Atmosphere Research 2023年第1期2卷 134-172页

作者： Qiang Wang Qi Shu Shizhu Wang Agnieszka Beszczynska-Moeller sergey Danilov Laura de Steur Thomas W.n.Haine Michael Karcher Craig M.Lee Paul G.Myers Igor V.Polyakov Christine Provost Øystein Skagseth Gunnar Spreen Rebecca Woodgate Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research(AWI) BremerhavenGermany First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdaoPeople’s Republic of China Shandong Key Laboratory of Marine Science and numerical Modeling QingdaoPeople’s Republic of China Institute of Oceanology Polish Academy of SciencesSopotPoland Department of Mathematics and Logistics Jacobs UniversityBremenGermany norwegian Polar Institute Fram CentreTromsøNorway Earth&Planetary Sciences The Johns Hopkins UniversityBaltimoreMDUSA .8Ocean Atmosphere Systems GmbH HamburgGermany Applied Physics Laboratory University of WashingtonSeattleWAUSA. Department of Earth and Atmospheric Sciences University of AlbertaEdmontonABCanada. International Arctic Research Center and College of natural Science and Mathematics University of Alaska FairbanksFairbanksAKUSA. Finnish Meteorological Institute HelsinkiFinland. Laboratoire LOCEAn-IPSL Sorbonne Université(UPMCUniversity Paris 6)CNRSIRDMNHNParisFrance. Institute of Marine Research and Bjerknes Centre of Climate Research BergenNorway. Institute of Environmental Physics University of BremenBremenGermany.

Arctic Ocean gateway fluxes play a crucial role in linking the Arctic with the global ocean and affecting climate and marine *** reviewed past studies on Arctic-Subarctic ocean linkages and examined their changes and driving *** review highlights that radical changes occurred in the inflows and outflows of the Arctic Ocean during the ***,the Pacific inflow temperature in the Bering Strait and Atlantic inflow temperature in the Fram Strait hit record highs,while the Pacific inflow salinity in the Bering Strait and Arctic outflow salinity in the Davis and Fram straits hit record *** the ocean heat convergence from lower latitudes to the Arctic and the hydrological cycle connecting the Arctic with Subarctic seas were stronger in 2000-2020 than in ***6 models project a continuing increase in poleward ocean heat convergence in the 21st century,mainly due to warming of inflow *** also predict an increase in freshwater input to the Arctic Ocean,with the largest increase in freshwater export expected to occur in the Fram Strait due to both increased ocean volume export and decreased *** Strait sea ice volume export hit a record low in the 2010s and is projected to continue to decrease along with Arctic sea ice *** quantitatively attribute the variability of the volume,heat,and freshwater transports in the Arctic gateways to forcing within and outside the Arctic based on dedicated numerical simulations and emphasize the importance of both origins in driving the variability.

关键词： Arctic ocean Strait