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Open Journal of Geology 2019年第8期9卷 474-496页

作者： Tamara Bayanova Viktor Subbotin Svetlana Drogobuzhskaya anatoliy nikolaev Ekaterina Steshenko Geological Institute Kola Science Centre Russian Academy of Sciences Apatity Russia Tananaev Institute of Chemistry Kola Science Centre Russian Academy of Sciences Apatity Russia

Baddeleyite is an important mineral geochronometer. It is valued in the U-Pb (ID-TIMS) geochronology more than zircon because of its magmatic origin, while zircon can be metamorphic, hydrothermal or occur as xenocrysts. Detailed mineralogical (BSE, KL, etc.) research of baddeleyite started in the Fennoscandian Shield in the 1990s. The mineral was first extracted from the Paleozoic Kovdor deposit, the second-biggest baddeleyite deposit in the world after Phalaborwa (2.1 Ga), South Africa. The mineral was successfully introduced into the U-Pb systematics. This study provides new U-Pb and LA-ICP-MS data on Archean Ti-Mgt and BIF deposits, Paleoproterozoic layered PGE intrusions with Pt-Pd and Cu-Ni reefs and Paleozoic complex deposits (baddeleyite, apatite, foscorite ores, etc.) in the NE Fennoscandian Shield. Data on concentrations of REE in baddeleyite and temperature of the U-Pb systematics closure are also provided. It is shown that baddeleyite plays an important role in the geological history of the Earth, in particular, in the break-up of supercontinents.

关键词： Baddeleyite PGE U-Pb Isotope Data Geochronology Paleoproterozoic PGE Layered Intrusion Complex Deposits Paleozoic Fennoscandian Shield

Saffman–Taylor instability in eccentric cylinders at gaseous cavitation

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Friction 2024年第2期12卷 356-362页

作者： anatoliy A.MONAKHOV Nikolay BUKHARIN Institute of Mechanics Moscow State UniversityMoscow 119899Russia ThermoFluid Solutions Ltd. CalgaryAlberta T3G4E8Canada

A flow of silicon fluid in the gap between eccentric cylinders was studied *** condition of gaseous cavitation inception during the rotation of internal cylinder was *** was shown that at reduction of the gap between cylinders Saffman–Taylor instability appeared on surface of the internal cylinder and then gaseous cavitation was *** of one uniform gas formation appearance under this type of instability was demonstrated.

关键词： gaseous cavitation Saffman-Taylor instability eccentric cylinders friction lubrication theory

On the radiative and thermodynamic properties of the cosmic radiations using COBE FIRAS instrument data: Ⅲ. Galactic far-infrared radiation

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Research in Astronomy and Astrophysics 2015年第7期15卷 939-952页

作者： anatoliy I Fisenko Vladimir Lemberg ONCFEC Inc.

Using the three-component spectral model describing the FIRAS average continuum spectra, the exact analytical expressions for thermodynamic and radiative functions of Galactic far-infrared radiation are obtained. The COBE FIRAS instrument data in the 0.15-2.88 THz frequency interval at the mean temperatures of T1= 17.72 K, T2= 14 K and T3= 6.73 K are used for calculating the radiative and thermodynamic functions, such as the total radiation power per unit area, total energy density, total emissivity, number density of photons, Helmholtz free energy density, entropy density, heat capacity at constant volume and pressure for the warm,intermediate-temperature and very cold components of the Galactic continuum spectra. The generalized Stefan-Boltzmann law for warm, intermediate-temperature and very cold components is constructed. The temperature dependence of each component is determined by the formula IS-B（T） = σ′ T6. This result is important when we construct the cosmological models of radiative transfer that can be applied inside the Galaxy. Within the framework of the three-component spectral model, the total number of photons in our Galaxy and the total radiation power（total luminosity） emitted from a surface of the Galaxy are calculated. Their values are N6Gtotal= 1.3780 × 108 and I3Gtotal（T） = 1.0482 × 106 W. Other radiative and thermodynamic properties of the Galactic far-infrared radiation（photon gas） of the Galaxy are calculated. The expressions for astrophysical parameters, such as the entropy density/Boltzmann constant and number density of the Galactic far-infrared photons are obtained. We assume that the obtained analytical expressions for thermodynamic and radiative functions may be useful for describing the continuum spectra of the far-infrared radiation for other galaxies.

关键词： Galaxy: general -- galaxies: general

Direct visualization of the complete evolution of femtosecond laser-induced surface structural dynamics of metals

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Light(Science & Applications) 2016年第1期5卷 58-64页

作者： Ranran Fang anatoliy Vorobyev Chunlei Guo The Institute of Optics University of RochesterRochesterNY 14627USA School of Science Chongqing University of Posts and TelecommunicationsChongqingChina The Guo China-US Photonics Laboratory Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchunChina

Despite extensive studies of femtosecond laser-material interactions,even the simplest morphological responses following femtosecond pulse irradiation have not been fully *** studies have revealed only partial *** we develop a zerobackground and high-contrast scattered-light-based optical imaging technique through which we capture,for the first time,the complete temporal and spatial evolution of the femtosecond laser-induced morphological surface structural dynamics of metals from start to finish,that is,from the initial transient surface fluctuations,through melting and ablation,to the end of *** find that transient surface structures first appear at a delay time on the order of 100 ps,which is attributed to ablation driven by pressure relaxation in the surface *** formation dynamics of the surface structures at different length scales are individually resolved,and the sequence of their appearance changes with laser fluence is *** and complete resolidification,observed here for the first time,are shown to occur more slowly than previously predicted by two orders of *** examine and identify the mechanisms driving each of these dynamic *** visualization and control of morphological surface structural dynamics not only are of fundamental importance for understanding femtosecond laser-induced material responses but also pave the way for the design of new material functionalities through surface structuring.

关键词： ablation femtosecond laser surface nano/microstructures ultrafast dynamics ultrafast imaging

Control of chaotic oscillations of a satellite

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Applied Mathematics and Mechanics(English Edition) 2007年第7期28卷 893-900页

作者： Alexey Bobtsov Nikolay nikolaev Olga Slita Department of Control Systems and Informatics Saint-Petersburg State University of Information Technologies Mechanics and OpticsKronverksky Ave.49Saint-Petersburg197101Russia

Analytical conditions and practical methods of their realization are proposed to solve a problem of a command signal tracking for a nonlinear disturbed system. Nonlinear disturbed plants consisting of linear dynamic block and nonlinear block in feedback are considered. Nonlinear part of the plant and disturbance are unknown and bounded. The paper illustrates a possibility of applications of proposed algorithms to control libration angle of satellite.

关键词： adaptive control chaotic behaviour satellite control nonlinear stabilization nonlinear control output control

Tunable vertical ferroelectricity and domain walls by interlayer sliding inβ-ZrI_(2)

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npj Computational Materials 2021年第1期7卷 1600-1608页

作者： Xiaonan Ma Chang Liu Wei Ren Sergey A.nikolaev Physics Department State Key Laboratory of Advanced Special Steeland International Center of Quantum and Molecular StructuresShanghai UniversityShanghai 200444China Materials Genome Institute and Shanghai Key Laboratory of High Temperature SuperconductorsShanghai UniversityShanghai 200444China Tokyo Tech World Research Hub Initiative(WRHI) Institute of Innovative ResearchTokyo Institute of Technology4259 NagatsutaMidori-kuYokohamaKanagawa 226-8503Japan Laboratory for Materials and Structures Tokyo Institute of Technology4259 NagatsutaMidori-kuYokohamaKanagawa 226-8503Japan National Institute for Materials Science MANA1-1 NamikiTsukubaIbaraki 305-0044Japan

Vertical ferroelectricity where a net dipole moment appears as a result of in-plane ionic displacements has gained enormous attention following its discovery in transition metal *** on first-principles calculations,we report on the evidence of robust vertical ferroelectricity upon interlayer sliding in layered semiconductingβ-ZrI_(2),a sister material of polar semimetals MoTe_(2)and WTe_(2).The microscopic origin of ferroelectricity in ZrI_(2)is attributed to asymmetric shifts of electronic charges within a trilayer,revealing a subtle interplay of rigid sliding displacements and charge redistribution down to ultrathin *** further investigate the variety of ferroelectric domain boundaries and predict a stable charged domain wall with a quasi-twodimensional electron gas and a high built-in electric field that can increase electron mobility and electromechanical response in multifunctional *** behaviour and a small switching barrier of ZrI_(2)hold promise for various ferroelectric applications,and our results provide important insights for further development of slidetronics ferroelectricity.

关键词： ferroelectric interlayer walls

Effect of the Laser Heating of Nanotube Nuclei on the Nanotube Type Population

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Nano Research 2009年第10期2卷 818-827页

作者： Pavel nikolaev William Holmes Edward Sosa Peter Boul Sivaram Arepalli Department of Energy Science Sungkyunkwan University300 Cheoncheon-dongJangan-guSuwon 440-746Korea Alan G.MacDiarmid NanoT ech Institute The University of Texas at Dallas800 West Campbell RoadRichardsonTX 75080USA ERC Inc./NASA Johnson Space Center Mail Stop ES-4P.O.Box 58561HoustonTX 77258USA

Many potential applications of carbon nanotubes are expected to benet from the availability of single-walled carbon nanotube materials enriched in metallic species,and specifically armchair *** present work focuses on the modification of the pulsed laser vaporization(PLV)technique to selectively produce certain carbon nanotube *** nuclei were“warmed-up”with an additional laser pulse,timed to coincide approximately with the nucleation *** effect of the second laser on the carbon vapor temperature was studied by emission *** type populations with and without warm-up were compared by means of absorption,photoluminescence,and Raman *** was found that the warm-up of nanotube nuclei with a laser pulse has a noticeable,albeit small,effect on the nanotube *** intensity of spectral features associated with(9,7)nanotube and its large chiral angle neighbors increased,while small chiral angle nanotubes decreased,with exception of the(15,0)*** experiment demonstrates that nanotube population during PLV synthesis can be manipulated in a controlled fashion.

关键词： Nanotube synthesis pulsed laser vaporization nanotube population

FSpot:Fast and Efficient Video Encoding Workloads Over Amazon Spot Instances

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Computers, Materials & Continua 2022年第6期71卷 5677-5697页

作者： anatoliy Zabrovskiy Prateek Agrawal Vladislav Kashansky Roland Kersche Christian Timmerer Radu Prodan University of Klagenfurt Klagenfurt9020Austria Lovely Professional University Phagwara144411India Petrozavodsk State University Petrozavodsk185035Russia Bitmovin Klagenfurt9020Austria

HTTP Adaptive Streaming(HAS)of video content is becoming an undivided part of the Internet and accounts for most of today’s network *** compression technology plays a vital role in efficiently utilizing network channels,but encoding videos into multiple representations with selected encoding parameters is a significant ***,video encoding is a computationally intensive and time-consuming operation that requires high-performance resources provided by on-premise infrastructures or public *** turn,the public clouds,such as Amazon elastic compute cloud(EC2),provide hundreds of computing instances optimized for different purposes and clients’***,there is a need for algorithms and methods for optimized computing instance selection for specific tasks such as video encoding and transcoding ***,the encoding speed directly depends on the selected encoding parameters and the complexity characteristics of video *** this paper,we first benchmarked the video encoding performance of Amazon EC2 spot instances using multiple×264 codec encoding parameters and video sequences of varying ***,we proposed a novel fast approach to optimize Amazon EC2 spot instances and minimize video encoding ***,we evaluated how the optimized selection of EC2 spot instances can affect the encoding *** results show that our approach,on average,can reduce the encoding costs by at least 15.8%and up to 47.8%when compared to a random selection of EC2 spot instances.

关键词： EC2 spot instance encoding time prediction adaptive streaming video transcoding clustering HTTP adaptive streaming MPEG-DASH cloud computing optimization Pareto front

Probing 10μK stability and residual drifts in the cross-polarized dual-mode stabilization of single-crystal ultrahigh-Q optical resonators

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Light(Science & Applications) 2019年第1期8卷 1170-1178页

作者： Jinkang Lim Wei Liang anatoliy A.Savchenkov Andrey B.Matsko Lute Maleki Chee Wei Wong Fang Lu Mesoscopic Optics and Quantum Electronics Laboratory University of CaliforniaLos AngelesCA 90095USA OEwaves Inc. 465 North Halstead StreetSuite 140PasadenaCA 91107USA

The thermal stability of monolithic optical microresonators is essential for many mesoscopic photonic applications such as ultrastable laser oscillators,photonic microwave clocks,and precision navigation and *** fundamental performance is largely bounded by thermal *** thermal monitoring can be achieved by utilizing cross-polarized dual-mode beat frequency metrology,determined by the polarization-dependent thermorefractivity of a single-crystal microresonator,wherein the heterodyne radio-frequency beat pins down the optical mode volume temperature for precision ***,we investigate the correlation between the dualmode beat frequency and the resonator temperature with time and the associated spectral noise of the dual-mode beat frequency in a single-crystal ultrahigh-Q MgF_(2) resonator to illustrate that dual-mode frequency metrology can potentially be utilized for resonator temperature stabilization reaching the fundamental thermal noise limit in a realistic *** show a resonator long-term temperature stability of 8.53μK after stabilization and unveil various sources that hinder the stability from reaching sub-μK in the current system,an important step towards compact precision navigation,sensing,and frequency reference architectures.

关键词： resonator polarization stabilization

Impact of environmental factors on the body shape variation and sexual shape dimorphism in Carabus granulatus L.(Coleoptera:Carabidae)

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Zoological Systematics 2017年第1期42卷 71-89页

作者： Raisa A. Sukhodolskaya anatoliy A. Saveliev Research Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences Kazan Tatarstan 420087 Russian Federation Kazan (Volga Region) State University Kazan Tatarstan 420012 Russian Federation

Despite plenty of data in insects shape variation, papers on environmental factors effect on such variation are scarce and in ground beetles are practically absent. The aim of this research was to：（i） model the effect of the region of habitation, urbanization and habitat vegetation into the shape variation in widespread carabid species; （ii） describe sexual shape dimorphism in studied species. Samples were pitfall trapped in different regions of its area in the spectrum of anthropogenic influence （cities, suburbs, natural biotopes）. One thousand and one hundred sixty-eight specimens were analyzed for six morphometric traits and terminal points of those measurements were used as landmarks for Procrustes analysis. We used linear models to reveal which factor （region, urbanization or vegetation） and in what direction affected beetles shape. Results showed that males in C. granulatus had more convex elytra and head, and the more convex in apical-basal direction pronotum. In its area from the east to the west elytra flattened in medial-distal direction and pronotum flattened in apical-distal direction. In disturbed urban environment beetles pronotum became more convex in both sexes and males elytra became more convex too. In open habitats （meadows, lawns） beetles became more flattened.

关键词： Ground beetles body shape variation sexual shape dimorphism latitudinalgradient urbanization.