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Hybrid model for prediction of welding distortions in large structures

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Frontiers of Materials Science 2011年第2期5卷 209-215页

作者： vesselin MICHAILOv nikolay DOYNOv Christoph STAPELFELD Ralf OSSENBRINK Chair of Joining and Welding Technology Brandenburg Technical University of Cottbus Konrad-Wachsmann-Allee 17 03046 Cottbus Germany

The paper presents a short overview of the contemporary approaches for calculating welding distortions. In order to meet the existing challenges, an advanced hybrid model for prediction of welding distortions in large structures is described. For the purpose of illustrating the capability of this model, a simulation case is put into discussion. The results are validated by comparison with experimental data, as well as with common simulation technique. Analysis of the calculation costs is also presented. The directions for development of calculation technique, based on the presented model, are also suggested.

关键词： hybrid model welding distortion calculation

Diffuse discharges in SF_(6)and mixtures of SF_(6)with H_(2),formed by nanosecond voltage pulses in non-uniform electric field

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High voltage 2018年第4期3卷 316-322页

作者： Alexei N.Panchenko victor F.Tarasenko Dmitry v.Beloplotov nikolay A.Panchenko Mikhail I.Lomaev Institute of High Current Electronics Siberian Branch(SB)Russian Academy of Sciences(RAS)Tomsk 634055Russia Faculty of Innovative Technologies National Research Tomsk State UniversityTomsk 634050Russia Department of Photonics and Quantum Electronics National Research Tomsk Polytechnic UniversityTomsk 634050Russia Department of Physics Tomsk State University of Control Systems and RadioelectronicsTomsk 634050Russia

Results of experimental study of nanosecond diffuse discharge in SF_(6)and gas mixtures of SF_(6)with H_(2),D_(2)and C_(2)H_(6)are *** aim of this work is to study parameters of discharge between two extended electrodes with a small radius of curvature in SF_(6)and SF_(6)with *** was shown that diffuse discharge can be formed in SF_(6)at elevated pressure between blade electrodes with length of 30 *** was also confirmed that in a sharply non-uniform electric field a beam of runaway electrons is generated and that the gap breakdown occurs due to ionisation waves which begin on electrodes with small radius of *** action in the infrared spectral region was obtained in SF_(6)-H_(2)(D_(2),C_(2)H_(6))*** laser output up to 110 mJ was easily achieved which corresponds to ultimate intrinsic efficiency(with respect to deposited energy)of 10%.

关键词： breakdown uniform radius

俄罗斯东北部提高寒冻土壤稳定性与肥力的工程措施(英文)

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冰川冻土 2004年第S1期26卷 179-183页

作者： nikolay v. Ukhov North-Eastern Research Station Melnikov Permafrost Institute SB RAS Gagarin St. 12 Magadan 685024 Russia

The rational usage of low productive cryogenic landscapes in the North-Eastern part of Russia is impossible without carrying out special engineering preparation\. The preventing from negativethat often has destructive cryogenic processesin the area of ice-covered permafrost soils, provided by its thawing into the marginally necessary depth in thewhole area. The simplest and the most effective engineering method of faulting as anage-old stock （reserve）of surplus moisture in the form of ice from the upper parts of permafrost soils is the creation of continuous furrows net on the wholesurface. This method also raises the fertility of soils, reducesacidity, and raises microbiological activity and the degree of internal structure decaying. Thermophysical calculations and the results of the field study in the experimental firing grounds are the availableevidences of this methodwhich raises thethermal stability of cryogenic landscapes while mastering of global climate changes in different parts of cryolithozone.

关键词： cryosols cryogenic processes furrow net thermokarst

New variable stars from the photographic archive:semi-automated discoveries,attempts at automatic classification and the new field 104 Her

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Research in Astronomy and Astrophysics 2018年第8期18卷 29-40页

作者： Sergei v.Antipin Ignacio Becker Alexander A.Belinski Darya M.Kolesnikova Karim Pichara nikolay N.Samus Kirill v.Sokolovsky Alia v.Zharova Alexandra M.Zubareva P.K.Sternberg Astronomical Institute M.V.Lomonosov Moscow University13University Ave.Moscow 119234Russia Pontificia Universidad Catolica de Chile SantiagoChile Institute of Astronomy Russian Academy of Sciences48Pyatnitskaya Str.Moscow 109017Russia Institute for Applied Computational Science Harvard UniversityCambridgeMAUSA IAASARS National Observatory of Athens15236 PenteliGreece Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str.84/32Moscow 117997Russia

Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute （Lomonosov Moscow University） in 1976-1994 and digitized with a resolution of 2400dpi, we dis- covered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type re- main not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys.

关键词： techniques photometric

Antiangiogenic therapy for portal hypertension in liver cirrhosis: Current progress and perspectives

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World Journal of Gastroenterology 2018年第33期24卷 3738-3748页

作者： Dmitry victorovich Garbuzenko nikolay Olegovich Arefyev Evgeniy Leonidovich Kazachkov Department of Faculty Surgery South Ural State Medical University Department of Pathological Anatomy and Forensic Medicine South Ural State Medical University

Developing medicines for hemodynamic disorders that are characteristic of cirrhosis of the liver is a relevant problem in modern hepatology. The increase in hepatic vascular resistance to portal blood flow and subsequent hyperdynamic circulation underlie portal hypertension(PH) and promote its progression, despite the formation of portosystemic collaterals. Angiogenesis and vascular bed restructurization play an important role in PH pathogenesis as well. In this regard, strategic directions in the therapy for PH in cirrhosis include selectively decreasing hepatic vascular resistance while preserving or increasing portal blood flow, and correcting hyperdynamic circulation and pathological angiogenesis. The aim of this review is to describe the mechanisms of angiogenesis in PH and the methods of antiangiogenic therapy. The Pub Med database, the Google Scholar retrieval system, and the reference lists from related articles were used to search for relevant publications. Articles corresponding to the aim of the review were selected for 2000-2017 using the keywords: "liver cirrhosis", "portal hypertension", "pathogenesis", "angiogenesis", and "antiangiogenic therapy". Antiangiogenic therapy for PH was the inclusion criterion. In this review, we have described angiogenesis inhibitors and their mechanism of action in relation to PH. Although most of them were studie donly in animal experiments, this selective therapy for abnormally growing newly formed vessels is pathogenetically reasonable to treat PH and associated complications.

关键词： Liver cirrhosis Portal hypertension Pathogenesis Angiogenesis Antiangiogenic therapy

Observation of nonlinear fractal higher order topological insulator

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Light(Science & Applications) 2024年第11期13卷 2699-2714页

作者： Hua Zhong victor O.Kompanets Yiqi Zhang Yaroslav v.Kartashov Meng Cao Yongdong Li Sergei A.Zhuravitskii nikolay N.Skryabin Ivan v.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Sergey v.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong University710049 Xi’anChina Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia

Higher-order topological insulators(HOTIs)are unique materials hosting topologically protected states,whose dimensionality is at least by 2 lower than that of the *** states in such insulators may be strongly confined in their corners which leads to considerable enhancement of nonlinear processes involving such ***,all nonlinear HOTIs demonstrated so far were built on periodic bulk lattice ***,we demonstrate the first nonlinear photonic HOTI with the fractal *** their fractional effective dimensionality,the HOTIs constructed here on two different types of the Sierpiński gasket waveguide arrays,may support topological corner states for unexpectedly wide range of coupling strengths,even in parameter regions where conventional HOTIs become *** demonstrate thresholdless spatial solitons bifurcating from corner states in nonlinear fractal HOTIs and show that their localization can be efficiently controlled by the input beam *** observe sharp differences in nonlinear light localization on outer and multiple inner corners and edges representative for these fractal *** findings not only represent a new paradigm for nonlinear topological insulators,but also open new avenues for potential applications of fractal materials to control the light flow.

关键词： materials. flow. topological

Phylogeny of Brucella abortus strains isolated in the Russian Federation

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Asian Pacific Journal of Tropical Medicine 2021年第7期14卷 323-329页

作者： Dmitry A.Kovalev Dmitriy G.Ponomarenko Sergey v.Pisarenko nikolay A.Shapakov Anna A.Khachaturova Natalia S.Serdyuk Olga v.Bobrysheva Alexander N.Kulichenko Stavropol Research Anti-Plague Institute 355035StavropolRussian Federation

Objective: To study Brucella(B.) abortus strains isolated in the Russian Federation, in order to identify their detailed position in the phylogenetic structure of the species global population as well as to determine genetic relationships for isolates from different geographical ***: Based on Bayesian method, the whole genome singlenucleotide polymorphism(SNP) analysis of 258 B. abortus strains from different geographical areas of the world including 20 B. abortus strains isolated in Russia was carried out. Results: The core genome SNP analysis of the B. abortus isolates allowed describing the main genetic lineages. The Russian strains entered two separate clades, including the basal branch and the C1 branch that is widely spread in Eurasia. The data on the isolation time was used for the dating of phylogenetic tree, and also the estimated time frame for the B. abortus genotype diversification was determined. There were sets of specific SNPs identified, which defined each of the genotypes and ***: A significant genetic diversity of the brucellosis pathogen strains from Russia has been proven. The sets of unique specific SNPs described in our study may become one of the elements within a bio-informational analysis algorithm to be used for epidemiological study of brucellosis outbreaks, including those caused by new(atypical) genetic variants of B. abortus.

关键词： Brucella abortus Phylogeny Evolution Genome SNP

Effect of electron injection in copper-contacted graphene nanoribbons

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Nano Research 2016年第9期9卷 2735-2746页

作者： Konstantin A.Simonov nikolay A.vinogradov Alexander S.vinogradov Alexander v.Generalov Gleb I.Svirskiy Attilio A.Cafolla Nils Martensson Alexei B. Preobrajenski Department of Physics and Astronomy Uppsala UniversityUppsala Box 51675120Sweden MAX Ⅳ Laboratory Lund UniversityLund Box 11822100Sweden v.A.Fock Institute of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia School of Physical Sciences Dublin City UniversityDublin 9Ireland

For practical electronic device applications of graphene nanoribbons (GNRs), it is essential to have abrupt and well-defined contacts between the ribbon and the adjacent metal lead. By analogy with graphene, these contacts can induce electron or hole doping, which may significantly affect the I/v characteristics of the device. Cu is among the most popular metals of choice for contact materials. In this study, we investigate the effect of in situ intercalation of Cu on the electronic structure of atomically precise, spatially aligned armchair GNRs of width N = 7 (7-AGNRs) fabricated via a bottom-up method on the Au(788) surface. Scanning tunneling microscopy data reveal that the complete intercalation of about one monolayer of Cu under 7-AGNRs can be facilitated by gentle annealing of the sample at 80 °C. Angle-resolved photoemission spectroscopy (ARPES) data clearly reflect the one-dimensional character of the 7-AGNR band dispersion before and after intercalation. Moreover, ARPES and core-level photoemission results show that intercalation of Cu leads to significant electron injection into the nanoribbons, which causes a pronounced downshift of the valence and conduction bands of the GNR with respect to the Fermi energy (ΔE ~ 0.5 ev). As demonstrated by ARPES and X-ray absorption spectroscopy measurements, the effect of Cu intercalation is restricted to n-doping only, without considerable modification of the band structure of the GNRs. Post-annealing of the 7-AGNRs/Cu/Au(788) system at 200 °C activates the diffusion of Cu into Au and the formation of a Cu-rich surface Au layer. Alloying of intercalated Cu leads to the recovery of the initial position of GNR-related bands with respect to the Fermi energy (E F), thus, proving the tunability of the induced n-doping.

关键词： graphene nanoribbons bottom-up method copper intercalation charge injection angle-resolved photoemission spectroscopy (ARPES) scanning tunneling microscopy

Genesis of pyroxenite veins in supra-subduction zone peridotites:Evidence from petrography and mineral composition of Egiingol massif(Northern Mongolia)

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China Geology 2020年第2期3卷 299-313页

作者： Anas A.Karimov Marina A.Gornova vasiliy A.Belyaev Aleksander Ya.Medvedev nikolay v.Bryanskiy A.P.vinogradov Institute of Geochemistry Siberian Branch of Russian Academy of Sciences IrkutskFavorskogo str.1A 664033Russia

Swarms of orthopyroxenite and websterite veins are found within Egiingol residual SSZ peridotite massif of Dzhida terrain(Central Asian Orogenic Belt,Northern Mongolia).The process of Egiingol pyroxenite veins formation is investigated using new major and trace element analyses of pyroxenite minerals,calculations of closure temperatures and composition of equilibrium *** pyroxenites show abundant petrographic and geochemical evidence for replacement of the residual peridotite minerals by ortho-and clinopyroxene due to melt-rock *** of peridotite olivines are found in pyroxenites,Cr#of spinel increases from peridotites to pyroxenites,and compositions of ortho-and clinopyroxene change from peridotite to *** authors show that calculated equilibrium melts for investigated pyroxenites are very similar to compositions of boninite lavas from the Dzhida ***,formation of pyroxenite veins most likely resulted from percolation of boninite melts through the Egiingol *** veins formed at first,followed by websterite ***,the authors assume that pyroxenite veins represent the channels for boninitic melts migration in supra-subduction environment.

关键词： Pyroxenite vein Boninite Partial melting Melt-rock interaction Supra-subduction zone peridotite Egiingol massif Dzhida terrain Central Asian Orogenic Belt Northern Mongolia