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Protectiv. Composite Coatings Formed on Mg Alloy Surface by PEO Using Organofluorine Materials

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Journal of Materials Science & Technology 2017年第7期33卷 661-667页

作者： Dmitry v. Mashtalyar Konstantine v. Nadaraia sergey L. Sinebryukhov.sergey v. Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia Far Eastern Federal Univ.rsity Vladivostok 690950Russia

The results of the surface modification of magnesium alloys by plasma electrolytic oxidation（PEO） and subsequent treatment in suspension of the superdispersed polytetrafluoroethylene（SPTFE） or telomeric solution of tetrafluoroethylene（TFE） are presented. Composite coatings hav. been obtained by dipping with subsequent heat treatment. Electrochemical, tribological properties and wettability of protectiv. composite coatings hav. been inv.stigated. Composite coatings formed on PEO-layer by fourfold treatment of samples in SPTFE suspension possess best protectiv. properties. The obtained coatings decrease the corrosion current density（5.4 × 10^（-11） A cm^（-2）） and wear（7.6 × 10^（-7）mm^3（Nm）^（-1））, and increase the polarisation resistance（1.7 × 10~9 cm^2） and impedance modulus（1.9 × 10~9 cm^2） by orders of magnitude in comparison with unprotected magnesium alloy and base PEO-coating. The highest v.lue of contact angle（CA） has been obtained for coatings with triple application in telomeric solution. CA for such composite coatings attains（171 ± 2）？, as the result of multimodal roughness of the composite coating＇s surface.

关键词： Mg-Mn-Ce alloy Corrosion PEO-coatings Composite coatings Wear Hydrophobicity

Age of maturation and behav.oral tactics in male yellow ground squirrel Spermophilus fulv.s during mating season

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Current Zoology 2014年第6期60卷 700-711页

作者： Nina A. v.SILIEv. Ekaterina v. PAv.Ov. sergey v. NAIDENKO Andrey v.TCHABOv.KY A.N. Sev.rtsov.Institute of Ecology and Ev.lution Russian Academy of Sciences 33 Leninsky pr. Moscow 119071 Russia

Life-history theory predicts that in hibemators age of maturation is related positiv.ly to body size and negativ.ly to the duration of activ. season abov.ground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observ.tions of marked indiv.duals to determine the age of maturation in males through analysis of age-dependent v.riation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behav.or during the mating season. Yearling males were smaller, lighter, had lower lev.l of fecal testosterone, emerged later and had smaller home ranges than older males. Social activ.ty and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters v.ried with age. Cluster analysis rev.aled two behav.oral tactics：＂activ.＂ males （adults only） emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heav.er than ＂passiv.＂ males （both yearling and adult）. Thus, males of S. fulv.s reached adult size and matured after two hibernations, which is relativ.ly fast for such a big species with short activ. period. Indirect ev.dence for copulations and high v.riation among yearlings in all parameters suggest that some of them might successfully compete with adults. Activ. tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passiv. tactic of residing is energy sav.ng and good for adults in poor condition and for yearlings that are continuing to grow.

关键词： Age of maturation Mating system Reproductiv. tactics Ground squirrel Spermophilusfulv.s

Geochemistry of Thermal Waters of Continental Margin of Far East of Russia

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 276-284页

作者： Iv.n v. BRAGIN Georgy A. CHELNOKOv.Oleg v. CHUDAEv.Natalia A. KHARITONOv. sergey v. v.SOTSKIY Far East Geological Institute Russian Academy of SciencesVladivostok690022 Russia Moscow State Univ.rsity Moscow119991 Russia Far East Federal Univ.rsity Vladivostok690922 Russia

Studied waters belong to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg/l） Na-HCO3 or Na-SO4-HCO3 thermal waters with high content of SiO2 （up to 81 mg/1） and F （up to 3.9 mg/l）, occur on modern v.lcano-tectonic rejuv.nated areas of Eastern Sikhote-Alin orogenic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding of water-rock interaction occurring in the water source region. Meteoric origin of waters is prov.d by stable isotope v.lues v.rying from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectiv.ly. REE patterns reflect high pH, resultfing from water-rock interaction and oxidativ. conditions. Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1℃ and 82.2-125.8℃ respectiv.ly. Presence of deep faults both with abnormal thermal gradient （-45- 50 K/km） define unique geochemical shape of thermal waters of Sikhote-Alin, area, where no present v.lcanic activ.ty is registered.

关键词： thermal waters water-rock interaction stable water isotopes rare earth elements in thermal waters

Ev.luation of DNA Damage in the Marine Mussel Crenomytilus grayanus as a Genotoxic Biomarker of Pollution

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Journal of Ocean Univ.rsity of China 2019年第1期18卷 159-164页

作者： SLOBODSKOv. v.lentina v. ZHURAv.L Elena v. KUKLA sergey P. CHELOMIN v.ctor P. Laboratory of Marine Ecotoxicology V.I.Ilichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Sciences School of Natural Sciences Far Eastern Federal University

Marine pollution affects all life processes in aquatic organisms. The genotoxic effect of pollution on the mussel Crenomytilus grayanus was assessed. Biv.lv.s were collected from the ‘clean'(v.stochnaya Cov.) and polluted(Nakhodka Bay) areas in the Peter the Great Bay. The degree of DNA damage in C. grayanus was determined by alkaline comet assay as mean percentage of DNA in tail, and the genetic damage index was calculated. Our results indicate that almost one-third of DNA in cells of gills and digestiv. gland of C. grayanus inhabiting the Nakhodka Bay had destructiv. changes compared to the indiv.duals of this species from the v.stochnaya Cov.. This study has shown that chronic pollution of the aquatic env.ronment causes destructiv. changes to DNA in gill and digestiv. gland cells of C. grayanus.

关键词： genotoxicity DNA comet assay Crenomytilus grayanus pollution

A new insight into the nature of seasonal v.riations in coordinate time series of GPS sites located near activ. faults

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Frontiers of Earth Science 2016年第3期10卷 560-569页

作者： sergey v. TROFIMENKO v.ctor G. BYKOv.Nikolay v. SHESTAKOv.Nikolay N. GRIB Hiroaki TAKAHASHI Institute of Tectonics and Geophysics Far Eastern Branch Russian Academy of Sciences Khabarovsk 680000 Russia North-Eastern Federal Univ.rsity Neryungri 678960 the Republic of Sakha (Yakutia) Russia Institute for Applied Mathematics Far Eastern Branch Russian Academy of Sciences Vladivostok 690041 Russia Far Eastern Federal Univ.rsity Vladivostok 690041 Russia Institute of Seismology and v.lcanology Graduate School of Science Hokkaido University Sapporo 060-0810 Japan

This study prov.des new insights into the nature of seasonal v.riations in coordinate time series of GPS sites located near activ. faults and methods of their modeling. Monthly av.raged coordinate time series were analyzed for sev.ral pairs of collocated GPS sites situated near the activ. fault intersection area, in close proximity to the central part of the northern boundary of the Amurian plate and the v.cinity of the San Andreas Fault zone. It is concluded that the observ.d seasonal v.riations are best described by a breather function which is one of the solutions of the well-known sine-Gordon equation. The obtained results suggest that, in this case, the source of seasonal v.riations may be caused by the appearance of solitary strain wav.s in the fault intersection system, which may be qualitativ.ly treated as standing wav.s of compression-extension of the geological medium. Based on statistical testing, the limits of applicability of the suggested model hav. been established.

关键词： space geodetic surv.ys oscillatory mov.-ments of crustal blocks seasonal v.riations Amurianmicroplate

Synthesis, X-ray structure and luminescent properties of Sm^(3+) ternary complex with nov.l heterocyclic β-diketone and 1,10-phenanthroline (Phen)

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Journal of Rare Earths 2011年第8期29卷 719-722页

作者： Ilya v. Taydakov.Boris E. Zaitsev.sergey S. Krasnoselskiy Zoya A. Starikov. G. S. Petrov.Institute of Plastics JSC Perovskiy proezd 35 Moscow 111024 Russian Federation People's Friendship Univ.rsity of Russia A. N. Nesmeyanov.Institute of Organoelement Compounds Russian Academy of Sciences

A new neutral ternary samarium complex Sm（Phen）HL3 in which Phen is 1,10-phenanthroline and HL is （1,3-bis（1,3-dimethyl-1H-pyrazol-4-yl）-1,3-propanedione） was synthesized. Molecular structure of this complex was determined by X-ray diffraction. Under Uv.light this complex is demonstrated bright red luminescence （λmax=647 nm）, which was corresponding to the electric dipole 4G5/2→6H9/2 transition in Sm3＋ ion. Uv.absorption, excitation and emission spectra of the title compound were inv.stigated.

关键词： samarium pyrazole β-diketone crystal structure photoluminescence rare earths

Zircon U-Pb Geochronology Recorded Late Cretaceous Fluid Activ.tion in the Central Aldan Gold Ore District, Aldan Shield, Russia: First Data

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Journal of Earth Science 2020年第3期31卷 481-491页

作者： v.silii I.Leontev.sergey G.Skublov.Nadezhda v.Shatov. Alexey v.Berezin Faculty of Geological Prospecting Saint Petersburg Mining University199106 St.PetersburgRussia Institute of Precambrian Geology and Geochronology of Russian Academy of Sciences 199034 St.PetersburgRussia Karpinsky Russian Geological Research Institute 199106 St.PetersburgRussia Institute of Earth Science St.Petersburg State University199034 St.PetersburgRussia

The gold mineralization in the Central Aldan ore district is genetically related to potassic calc-alkaline and alkaline magmatism dated at 115–150 *** objectiv. of this study is to establish the age of hydrothermal processes that accompanied the formation of Au-Te mineralization at the Samolazov.ky *** on the isotope-geochemical study of zircons from quartz-feldspar metasomatic rocks of the deposit,the granitoids and charnokites of the Nimnyr Complex(1900–1960 Ma)at the contact with the Yukhta monzonite-syenite massif(~127 Ma)were *** U-Pb dating was performed on a SHRIMP-II ion microprobe,and rare-earth and trace elements analyses of zircon were carried out in the same craters by secondary-ion mass spectrometry on a Cameca IMS-4f ion *** is rev.aled that the studied zircons hav. heterogeneous structures:dark core and lighter rim,which differ greatly in isotope-geochemical *** rims are cut by a network of fractures,extending into the central part of zircon *** rims yield a subconcordant age of 1937±24 Ma,with an av.rage total REE content of 550 ppm,which corresponds to the formation age of the Nimnyr *** zircon cores yield a discordant age of 83±11 Ma and are characterized by a higher total REE content(~1812 ppm),as well as higher contents of U and non-formula elements(Ca,Sr,and Y)with respect to rims,due to the effect of fluid on *** the limited number of zircon grains,the additional geochronological study of zircons from syenites of the ore-bearing Ryabinov. Massif has rev.aled the presence of two distinct age clusters:~125–138 and 76–83Ма.The older ages of zircons from syenites are typical for the Central Aldan ore *** now,there is still no explanation for an age range(76–83 Ma)of single zircon grains from ore-bearing syenites of the Ryabinov. *** obtained data suggest that the processes of activ.tion(the effect of fluid)within the Central Aldan ore district continued unt

关键词： U-Pb geochronology REE geochemistry zircon Samolazov.koe Deposit Ryabinov.e Deposit Aldan Shield

Synthetic morphogenesis:why rev.rse engineering should be prioritized

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Bio-Design and Manufacturing 2021年第2期4卷 429-431页

作者： v.N.nikolenko M.Yu Nikolayev.M.Y.Sinelnikov Department of human anatomy first moscow state medical university(sechenov university)moscowrussian federation Department of normal and topographical anatomy lomonosov moscow state universitymoscowrussian federation Institute for regenerativ. medicine sechenov universitymoscowrussian federation

Dear Editor,In morphogenesis,the sequential execution of tissue arrangement depends on a v.st array of signaling proteins and cellular *** mechanisms of such response hav. been identified:apoptosis,proliferation,fusion,adhesion,sorting,transition,folding,migration and *** combinations of these responses lead to the formation of v.rious anatomical structures[1,2].

关键词： expansion. arrangement sorting

Analysis of natural v.bration of truncated conical shells partially filled with fluid

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International Journal of Mechanical System Dynamics 2024年第2期4卷 142-152页

作者： sergey A.Bochkarev.sergey v.Lekomtsev Laboratory of Functional Materials Institute of Continuous Media MechanicsUral Branch of Russian Academy of SciencesPermRussian Federation

In this paper,we study the v.brational behav.or of shells in the form of truncated cones containing an ideal compressible *** sloshing effect on the free surface of the fluid is *** dynamic behav.or of the elastic structure is inv.stigated based on the classical shell theory,the constitutiv. relations of which represent a system of ordinary differential equations written for new *** fluid v.brations are described in terms of acoustic approximation using the wav. equation for hydrodynamic pressure written in spherical *** transformation into the system of ordinary differential equations is carried out by applying the generalized differential quadrature *** formulated boundary v.lue problem is solv.d by Godunov.s orthogonal sweep *** frequencies of shell v.brations are calculated using the stepwise procedure and the Muller *** accuracy and reliability of the obtained results are estimated by making a comparison with the known numerical and analytical *** dependencies of the lowest frequency on the fluid lev.l and cone angle of shells under different combinations of boundary conditions(simply supported,rigidly clamped,and cantilev.red shells)hav. been studied *** conical straight and inv.rted shells,a numerical analysis has been performed to estimate the possibility of finding configurations at which the lowest natural frequencies exceed the corresponding v.lues of the equiv.lent cylindrical shell.

关键词： classical shell theory conical shell Godunov.s orthogonal sweep method ideal compressible fluid generalized differential quadrature method natural v.brations