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Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii n.kozlov Ekaterina V.LEBEDEVA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： Volcanic lakes Echolocation survey Volcanism Gashydrotherms Kamchatka Kuril Islands

U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy n.kozlov Ekaterina n.Fomina Qiuli Li Jiao Li Geological Institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1)quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1 Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~125 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=18.1±0.1,^(207)Pb/^(204)Pb=15.3±0.1,and^(207)Pb/^(206)Pb=0.84±0.01)are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

Coronary revascularization in the elderly with stable angina

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Journal of Geriatric Cardiology 2015年第5期12卷 555-568页

作者： Kirill Lenarovich kozlov aleksandr Andreevich Bogachev Laboratory of Age-Related Clinical Pathology Department of Clinical Gerontology and Geriatrics St. Petersburg Institute of Bioregulation and Gerontology Northwestern Branch Russian Academy of Medical Sciences Saint-Petersburg Russia Department of Cardiovascular Medicine Kirov Military Medical Academy Saint-Petersburg Russia

A proportion of elderly with coronary artery disease is rapidly growing. They have more severe coronary artery disease, therefore, derive more benefit fi＇om revascularization and have a greater need for it. The elderly is a heterogeneous group, but compared to the younger cohort, the choice of the optimal revascularization method is much more complicated among them. In recent decades, results has improved dramatically both in surgery and percutaneous coronary intervention （PCI）, even in very old persons. Despite the lack of evidence in elderly, it is obvious, that coronary artery bypass surgery （CABG） has a more pronounced effect on long-term survival in price of more strokes, while PCI is certainly less invasive. Age itself is not a criterion for the selection of treatment strategy, but the elderly are often more interested in quality of life and personal independence instead of longevity. This article discusses the factors that influence the choice of the revascularization method in the elderly with stable angina and presents a complex algorithm for making an individual risk-benefit profile. As a consequence the features of CABG and PCI in elderly patients are exposed. Emphasis is centered on the frailty and non-medical factors, including psychosocial, as essential components in making the decision of what strategy to choose. Good communication with the patients and giving them unbiased information is encouraged.

关键词： Angina Cardiopulmonary bypass Coronary artery disease Stents The elderly

Environmental performance assessments of different methods of coal preparation for use in small-capacity boilers: experiment and theory

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International Journal of Coal Science & Technology 2023年第5期10卷 57-71页

作者： A.n.kozlov E.P.Maysyuk I.Yu.Ivanova Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk130Lermontov664033Russia

The purpose of this article is to receive environmental assessments of combustion of different types of coal fuel depending on the preparation(unscreened,size-graded,briquetted and heat-treated)in automated boilers and boilers with manual *** assessments were made on the basis of data obtained from experimental methods of coal preparation and calculated methods of determining the amount of pollutant and greenhouse gas emissions,as well as the mass of ash and slag *** main pollutants from coal combustion are calculated:particulate matter,benz(a)pyrene,nitrogen oxides,sulfur dioxide,carbon *** the greenhouse gases carbon dioxide is *** a result of conducted research it is shown that the simplest preliminary preparation(size-graded)of coal significantly improves combustion efficiency and environmental performance:emissions are reduced by 13%for hard coal and up to 20%for brown *** introduction of automated boil-ers with heat-treated coal in small boiler facilities allows to reduce emissions and ash and slag waste by 2-3 *** best environmental indicators correspond to heat-treated lignite,which is characterized by the absence of sulfur dioxide emissions.

关键词： Coal preparation Automated and hand-fed coal boilers Environmental performance metrics

Energy of Grain Boundaries of Different Type in fcc Solid Solutions,Ordered Alloys and Intermetallics with L1_2 Superstructure

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Journal of Materials Science & Technology 2003年第6期19卷 593-596页

作者： O.B.Perevalova E.V.Konovalova n.A.Koneva E.V.kozlov Institute of Strength Physics and Materials Science Russian Academy of Science Siberian Branch Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia Tomsk

The study of the triple junctions of the grain boundaries in some fee solid solutions, ordered alloys and intermetallics with L12 has been carried out using the optical metallography and TEM methods. Two-types of the triple junctions were found in the alloys investigated (1), consisting of the boundaries of the random (RT), and (2), consisting of the RT boundary and the special boundaries (ST). The relative values of the RT and ST boundary energy were determined on the basis of the measurements of the angles between the grain boundary planes. It has been shown that the energy of ST boundaries increases with the increase of the stacking fault (SF) energy. The energy of the RT boundaries does not depend on the SF energy.

关键词： Alloys Grain boundary energy Stacking fault Anti-phase-boundary

Structural Changes and Electrodynamic Effects in Polymers under Fast Uniaxial Compression

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Chinese Journal of Polymer Science 2021年第5期39卷 601-609,I0007页

作者： Aleksey.I.aleksandrov Ivan A.aleksandrov Vitaliy G.Shevchenko aleksandr n.Ozerin n.S.Enikolopov Institute of Synthetic Polymeric Materials RAS 117393 Moscow Profsoyuznaya70 Russian Federation

Rheological explosion in polymers under uniaxial compression in an open volume occurs at the end of continuous rapid plastic deformation after several stages of *** types of polymers were chosen for this study:brittle glassy amorphous polystyrene and thermoplastic semi-crystalline *** pulses were detected during explosion,and their spectra were analyzed with two models.X-ray diffraction methods were used to investigate changes in the structure and morphology of polymers during deformation and rheological *** pores appear in polymer in this process,and their shape and size distribution were derived from X-ray *** main reason for the formation of pores in polymer samples in rheological explosion experiments is the intense microshifts in the polymer volume under the action of high applied pressure.

关键词： Polystyrene Polypropylene X-ray Mechanical properties Compression

Unveiling the nature of Polar-ring Galaxies from Deep Imaging

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Research in Astronomy and Astrophysics 2022年第11期22卷 34-50页

作者： aleksandr V.Mosenkov Vladimir P.Reshetnikov Maria n.Skryabina Zacory Shakespear Department of Physics and Astronomy N283 ESCBrigham Young UniversityProvoUT 84602USA Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye Chaussee 65/1196140 St.PetersburgRussia St.Petersburg State University 7/9 Universitetskaya Nab.199034 St.PetersburgRussia

General structural properties and low surface brightness tidal features hold important clues to the formation of *** this paper,we study a sample of polar-ring galaxies(PRGs)based on optical imaging from the Sloan Digital Sky Survey Stripe 82 and other deep *** investigate the deepest images of candidates for PRGs to *** carry out photometric decomposition on the host galaxies and associated polar structures that allows us to derive the structural properties of both *** are able to detect very faint tidal structures around most PRGs in our *** several galaxies,we can directly observe the formation of the polar ring due to merging,which is manifested in debris of the victim galaxy and an arc-like polar structure made up of its *** a few cases,we can discern signs of tidal *** results obtained indicate that the gravitational interaction and merging of galaxies are the most plausible mechanisms for the formation of PRGs.

关键词： data analysis techniques:photometric galaxies:structure

The Study of the Secrets of the Genetic Code

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Journal of Computer and Communications 2018年第7期6卷 64-83页

作者： n. n.kozlov Keldysh Institute of Applied Mathematics of Russian Academy of Sciences Moscow Russia

The disclosure of many secrets of the genetic code was facilitated by the fact that it was carried out on the basis of mathematical analysis of experimental data: the diversity of genes, their structures and genetic codes. new properties of the genetic code are presented and its most important integral characteristics are established. Two groups of such characteristics were distinguished. The first group refers to the integral characteristics for the areas of DnA, where genes are broken down in pairs and all 5 cases of overlap, allowed by the structure of DnA, were investigated. The second group of characteristics refers to the most extended areas of DnA in which there is no genetic overlap. The interrelation of the established integral characteristics in these groups is shown. As a result, a number of previously unknown effects were discovered. It was possible to establish two functions in which all the over-understood codons in mitochondrial genetic codes (human and other organizations) participate, as well as a significant difference in the integral characteristics of such codes compared to the standard code. Other properties of the structure of the genetic code following from the obtained results are also established. The obtained results allowed us to set and solve one of the new breakthrough problems—the calculation of the genetic code. The full version of the solution to this problem was published in this journal in August 2017.

关键词： Genetic Code Overlapping Genes Degeneracy Code Code Irregularities Potential Code for Overlaps Common Property Codes Integral Characteristics Code Deviation Code Elementary Overlaps Role-Reinterpreted Codons Code Is not Arbitrary

Computation of the Genetic Code: Full Version

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Journal of Computer and Communications 2017年第10期5卷 78-94页

作者： n. n. kozlov Keldysh Institute of Applied Mathematics of Russian Academy of Sciences Moscow Russia

One of the problems in the development of mathematical theory of the genetic code (summary is presented in [1], the detailed—to [2]) is the problem of the calculation of the genetic code. Similar problem in the world is unknown and could be delivered only in the 21st century. One approach to solving this problem is devoted to this work. For the first time a detailed description of the method of calculation of the genetic code was provided, the idea of which was first published earlier [3]), and the choice of one of the most important sets for the calculation was based on an article [4]. Such a set of amino acid corresponds to a complete set of representation of the plurality of overlapping triple gene belonging to the same DnA strand. A separate issue was the initial point, triggering an iterative search process all codes submitted by the initial data. Mathematical analysis has shown that the said set contains some ambiguities, which have been founded because of our proposed compressed representation of the set. As a result, the developed method of calculation was reduced to two main stages of research, where at the first stage only single-valued domains were used in the calculations. The proposed approach made it possible to significantly reduce the amount of computation at each step in this complex discrete structure.

关键词： Genetic Code Overlapping Genes Uniform Overlap Computation Code