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Mathematical modeling of icing process of the outer surface of the hull for a marine vessel

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Journal of Hydrodynamics 2023年第2期35卷 232-239页

作者： Konstantin Koshelev Andrey Osipov sergei Strijhak Nikita Tryaskin ISP RAS MoscowRussia Saint-Petersburg State Marine Technical University Saint-PetersburgRussia

The task of studying the process of icing is important due to the operation of large ships and fishing vessels in the seas of the Arctic *** this paper the ice accretion simulation for fishing vessel has been done at different Reynolds and Froude numbers.A hybrid approach was used for modeling:first,the approach based on Reynolds-averaged Navier-Stokes(RANS)model and volume of fluid(VOF)method with interDyMFoam solver was used for ship modelling in waves,second,RANS model and Euler-Lagrangian approach with iceFoam solver for ice accretion process modelling for ship with hull was *** k-ωSST turbulence model with wall functions was used for the RANS *** the help of the interDyMFoam solver,the position of water jet and liquid droplets in space were determined during the movement of the ship and taking into account the waves in the *** the help of iceFoam solver,the process of ice accretion on the surface of the vessel was *** calculations were run for different number Reynolds,*** analysis of mesh convergency was *** distribution of ice thickness and water film on the ship’s surface is *** simulations were performed on a high-performance cluster in parallel mode.

关键词： Ship sea safety climate movement modelling turbulence model water spray droplets velocity ice film mass

Spiral attractor created by vector solitons

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Light(Science & Applications) 2014年第1期3卷 355-362页

作者： Sergey V Sergeyev Chengbo Mou Elena g Turitsyna Alexey Rozhin sergei K Turitsyn Keith Blow Aston Institute of Photonic Technologies Aston UniversityBirmingham B47ETUK

Mode-locked lasers emitting a train of femtosecond pulses called dissipative solitons are an enabling technology for metrology,high-resolution spectroscopy,fibre optic communications,nano-optics and many other fields of science and ***,the vector nature of dissipative solitons has been exploited to demonstrate mode locked lasing with both locked and rapidly evolving states of ***,for an erbium-doped fibre laser mode locked with carbon nanotubes,we demonstrate the first experimental and theoretical evidence of a new class of slowly evolving vector solitons characterized by a double-scroll chaotic polarisation attractor substantially different from Lorenz,Ro¨ssler and Ikeda strange *** underlying physics comprises a long time scale coherent coupling of two polarisation *** observed phenomena,apart from the fundamental interest,provide a base for advances in secure communications,trapping and manipulation of atoms and nanoparticles,control of magnetisation in data storage devices and many other areas.

关键词： chaos mode-locked laser polarisation phenomena vector soliton

Mid-Miocene thermal impact on the lithosphere by sub-lithospheric convective mantle material:Transition from high-to moderate-Mg magmatism beneath Vitim Plateau,Siberia

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geoscience Frontiers 2017年第4期8卷 753-774页

作者： Irina Chuvashova sergei Rasskazov Tatyana Yasnygina Institute of the Earth's Crust Siberian Branch of RAS Irkutsk State University

High-Mg lavas are characteristic of the mid-Miocene volcanism in Inner *** the Vitim Plateau,small volume high-Mg volcanics erupted at 16-14 *** were followed with voluminous moderate-Mg lavas at 14-13 *** the former unit,we have recorded a sequence of（1） initial basaltic melts,contaminated by crustal material,（2） uncontaminated high-Mg basanites and basalts of transitional（K-Na-K） compositions,and（3） picrobasalts and basalts of K series;in the latter unit a sequence of（1） initial basalts and basaltic andesites of transitional（Na-K-Na） compositions and（2） basalts and trachybasalts of K-Na *** pressure estimation,we infer that the high-Mg melts were derived from the sublithospheric mantle as deep as 150 km,unlike the moderate-Mg melts that were produced at the shallow *** 14-13 Ma rock sequence shows that initial melts equilibrated in a garnet-free mantle source with subsequently reduced degree of melting garnet-bearing *** melting of relatively depleted lithospheric material,evidenced by mantle xenoliths,was involved in melting,*** suggest that the studied transition from high-to moderate-Mg magmatism was due to the mid-Miocene thermal impact on the lithosphere by hot sub-lithospheric mantle material from the Transbaikalian low-velocity（melting） domain that had a potential temperature as high as 1510℃.This thermal impact triggered rifting in the lithosphere of the Baikal Rift Zone.

关键词： Volcanism geodynamics Cenozoic Asia Asthenosphere Lithosphere

Paleocene A-type igneous suites in the Sikhote-Alin(the East Asian continental margin):Petrological,geochronological,isotopic,and geodynamic constraints

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geoscience Frontiers 2023年第6期14卷 386-413页

作者： Andrei V.grebennikov sergei A.Kasatkin Far East geological Institute Far Eastern Branch of the Russian Academy of Sciences159Prospekt 100-letiya VladivostokaVladivostok 690022Russian Federation

global geodynamic reconstruction models of the Pacific margin of Asia refer to materials collected throughout Japan,Korea and northeastern China,but they lack data on southern ***,the Sikhote-Alin orogenic belt(NE Asia)constituted a single eastern margin of the paleo-Asian continent with the abovementioned territories in the *** isotopic,geochemical,and geochronological data show that Paleocene igneous activity(-61-55 Ma)is widely developed in south-ern *** rock compositions of the igneous rocks of this period yield ferroan,peraluminous,calc-alkaline to alkaline affinities,highly abundant LILE and HFSE(with pronounced Ba,Sr,Eu,and Ti neg-ative anomalies)and depleted *** initial melts,displaying Zr+Y+Ce+Nb>350 ppm and 10,000×ga/Al>2.6,derived from an OIB-like mantle source crystallised under fairly reducing conditions(below FMQ buffer),and yield high temperature of zircon saturation(>850℃),indicating typical A-type granite and related volcanic rock *** is logical to associate variations in A-type rock geochemical composition with an enrichment of the upper part of the magma chamber with fluid-mobile components involving a reditribution of major and trace elements through fluid-magmatic *** depletion in Ca,Mg,Ba,Sr,Eu in the A-type rocks is caused by an outflow of these elements by an oxi-dizing,initially reduced,acidic fluid beyond the zone of magma ***-rock Sr-Nd isotope data argue for the generation of the A-type rocks by melting of dominantly a juvenile mantle component with a subordinate component of the ancient *** variations of igneous rocks of the reference area:^(87)Sr/^(86)Sr(t)(0.7024-0.7118),ε_(Nd)(t)(-0.9 to-5.1)and T_(DM2)(934-1277 Ma),result from the mixing of the OIB-like mantle source with selective melts or from the metapelite contamination of the Samarka terrane accretionary prism and of the Zhuravlevka-Amur turbidite basin,later followed by fluid-magma

关键词： Post-subduction magmatism Slab tear Sub-slab asthenosphere Strike-slip tectonic setting Lanthanide tetrad effect

Translocation of Otostegia bucharica, a highly threatened narrowly distributed relict shrub

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Plant Diversity 2019年第2期41卷 105-108页

作者： Komiljon Tojibaev Natalia Beshko sergei Volis Institute of Botany of Academy of Sciences of the Republic of Uzbekistan Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences

Translocation is a recognized means of rescuing imperiled species but the evidence for the long-term success of translocations is limited. We report the successful translocation of reproductive individuals of a critically endangered shrub Otostegia bucharica from a site facing imminent habitat destruction into a nearby natural population of the species. The relocated plants were visited the year after planting and 13 years later to assess short-and long-term plant survival. Significant percentage of plants that survived transplanting shock and very dry spring following transplanting(around 36%), and further decrease of this number in the next 12 years by only 14%, indicated that O. bucharica is amenable to translocation using reproductive plants. Based on results of species distribution modeling, and failed attempts of ex situ cultivation, we propose introduction of this species into areas with suitable climatic and soil ***, because there is currently no nature reserve in Uzbekistan having suitable conditions for the species under the present climate and that expected in the near future, and because all known habitats of O. bucharica are exposed to the very strong anthropogenic pressure, establishment of a new protected area, awareness building and involvement of local community in conservation activities are required to prevent extinction of this extremely rare species.

关键词： Endangered plant species SDM Translocation Ins itu Plant conservation

Strain engineering of electro-optic constants in ferroelectric materials

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npj Computational Materials 2019年第1期5卷 1092-1096页

作者： Charles Paillard sergei Prokhorenko Laurent Bellaiche Department of Physics and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA

Electro-optic effects allow control of the ow of light using electric fields,and are of utmost importance for today’s information and communication technologies,such as TV displays and fiber *** search for large electro-optic constants in films is essential to the miniaturization and increased efficiency of electro-optic *** this work,we demonstrate that strain-engineering in PbTiO_(3) films allows to selectively choose which electro-optic constant to *** electro-optic constants larger than 100 pm V^(−1) are predicted,either by driving the softening of an optical phonon mode at a phase transition boundary under tensile strain,or by generating the equivalent of a negative pressure via compressive strain to obtain large piezoelectric *** particular,a r_(13) electro-optic coefficient twice as large as the one of the commonly used LiNbO_(3) electro-optic material is found here when growing PbTiO_(3) on the technologicallyimportant Si substrate.

关键词： softening constants ferroelectric

Fine-scale spatial genetic structure in predominantly selfing plants with limited seed dispersal： a rule or exception？

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植物分类与资源学报 2016年第2期38卷 75-81页

作者： sergei Volis Danara Ormanbekova Irina Shulgina Key Laboratory of Biodiversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China Department of Agricultural Sciences University of Bologna Via Zamboni 33 40126 Bologna Italy

gene flow at a fine scale is still poorly understood despite its recognized importance for plant population demographic and genetic *** tested the hypothesis that intensity of gene flow will be lower and strength of spatial genetic structure(SgS) will be higher in more peripheral populations because of lower population *** study was performed on the predominantly selfing Avena sterilis and included:(1) direct measurement of dispersal in a controlled environment;and(2) analyses of SgS in three natural populations,sampled in linear transects at fixed increasing inter-plant *** found that in *** major seed dispersal is by gravity in close(less than 2 m) vicinity of the mother plant,with a minor additional effect of *** of SgS with six nuclear SSRs revealed a significant autocorrelation for the distance class of 1 m only in the most peripheral desert population,while in the two core populations with Mediterranean conditions,no genetic structure was *** results support the hypothesis that intensity of SgS increases from the species core to periphery as a result of decreased within-population gene flow related to low plant *** findings also show that predominant self-pollination and highly localized seed dispersal lead to SgS at a very fine scale,but only if plant density is not too high.

关键词： gene flow Neighborhood size Spatial genetic structure Range position Core Periphery

Catalytic enantioselective synthesis of β-amino alcohols by nitrene insertion

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Science China Chemistry 2021年第3期64卷 452-458页

作者： Zijun Zhou Yuqi Tan Xiang Shen sergei Ivlev Eric Meggers Fachbereich Chemie Philipps-Universitat MarburgHans-Meerwein-Strasse 435043 MarburgGermany

Chiral β-amino alcohols are important building blocks for the synthesis of drugs, natural products, chiral auxiliaries, chiral ligands and chiral organocatalysts. The catalytic asymmetric β-amination of alcohols offers a direct strategy to access this class of molecules. Herein, we report a general intramolecular C(sp^(3))–H nitrene insertion method for the synthesis of chiral oxazolidin-2-ones as precursors of chiral β-amino alcohols. Specifically, the ring-closing C(sp^(3))–H amination of N-benzoyloxycarbamates with 2 mol% of a chiral ruthenium catalyst provides cyclic carbamates in up to 99% yield and with up to 99% *** method is applicable to benzylic, allylic, and propargylic C–H bonds and can even be applied to completely non-activated C(sp^(3))–H bonds, although with somewhat reduced yields and stereoselectivities. The obtained cyclic carbamates can subsequently be hydrolyzed to obtain chiral β-amino alcohols. The method is very practical as the catalyst can be easily synthesized on a gram scale and can be recycled after the reaction for further use. The synthetic value of the new method is demonstrated with the asymmetric synthesis of a chiral oxazolidin-2-one as intermediate for the synthesis of the natural product aurantioclavine and chiral β-amino alcohols that are intermediates for the synthesis of chiral amino acids, indane-derived chiral Box-ligands, and the natural products dihydrohamacanthin A and dragmacidin A.

关键词： asymmetric catalysis nitrene amination chiral-at-metal ruthenium

Stability analysis of a deterministic model of Zika/Dengue co-circulation

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International Journal of Biomathematics 2019年第4期12卷 215-253页

作者： Mike Binder sergei S.Pilyugin Department of Mathematics University of FloridaUSA

We consider a deterministic model of Zika and Dengue viruses co-circulating in a human population. We study the system of differential equations modeling the dynamics of the diseases that can either be transmitted directly (host-to-host) or indirectly (host-vectorhost).We use an SIR model for hosts and an SI model for vectors in the homogeneous populations. The stability of the model has been analyzed both qualitatively and quantitatively.

关键词： Zika Dengue secondary infection