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All-optical dynamic focusing of light via coherent absorption in a plasmonic metasurface

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Light(Science & Applications) 2017年第1期6卷 114-120页

作者： Maria Papaioannou Eric Plum Edward TF Rogers nikolay I Zheludev Optoelectronics Research Centre and Centre for Photonic Metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK Institute for Life Sciences University of SouthamptonHighfieldSouthampton SO171BJUK Centre for Disruptive Photonic Technologies School of Physical and Mathematical Sciences and The Photonics InstituteNanyang Technological UniversitySingapore 637371Singapore

Vision,microscopy,imaging,optical data projection and storage all depend on focusing of *** focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or *** we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam *** use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter,allowing operation in the regimes of coherent absorption and coherent *** of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same *** altering the control pattern,its phase,or its intensity,we switch the lens function on and off,and alter the focal spot’s depth,diameter and *** occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators,which is orders of magnitude faster than conventional dynamic focusing technologies.

关键词： all-optical dynamic focusing coherent control coherent perfect absorption metasurfaces

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

SnSi nanocrystals of zinc-blende structure in a Si matrix

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Nano Research 2015年第12期8卷 3905-3911页

作者： Alexander Tonkikht Andrey Klavsyuk nikolay Zakharov Alexander Saletsky Peter Werner Max Planck Institute of Microstructure Physics Halle(Saale) 06120 Germany Faculty of Physics Moscow State University Moscow 119991 Russian Federation

A zinc-blende （sphalerite） crystallographic structure of SnSi nanocrystals generated by molecular-beam epitaxy is observed by electron microscopy techniques in a Si matrix. Ab initio density-functional modeling reveals a stabilizing effect of the Si matrix, which results in the lowest formation enthalpy of SnSi nanocrystals having the unexpected zinc-blende structure. Such nanocrystals could be applied in Si photonics to function as non-centrosymmetric media for the nonlinear optical process of second harmonic generation.

关键词： epitaxy density functional theory zinc-blende Si-Sn alloy

Study on Russian Natural Gas Export Strategy

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Study on Russian Natural Gas Export Strategy

作者： nikolay Khovrov 中国石油大学(北京)

学位级别：硕士

Natural gas industry takes one of the biggest role of Russian *** relations between Russia and other countries significantly depend by natural gas supply,where the pricing mechanism takes the key ***,it shows a solid desire to study the Russian natural gas export *** thesis firstly summarized the general theory of the natural gas mechanism and pricing practice forming of Russian and foreign ***,this thesis takes an analysis of Gazprom’s statistics from 1995 to *** on the factors affecting on the price of natural gas,this thesis formulates an econometric model to identify the dependence of Russian gas price on the border of Germany by variables such as the price of oil,the price of gas on NBP and the volume of exported *** on the identified parameters,this thesis determines the dependence of imported gas price to China from Russia from the volume of deliveries,prices of oil and the LNG *** this thesis establishes the optimal price for Russian natural gas to the Chinese *** that investigates political factors that impacts on Russian gas export *** conclusion,this thesis sum up the study,describes the prospects of Russian gas exports to Europe – which is seek to abandon the Ukrainian transit by *** declare the factors that can change the situation in the partnership between Russia and *** pointed that the price of gas has a strong dependence on the price of oil and continues to depend on it.

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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

Controlling light-with-light without nonlinearity

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Light(Science & Applications) 2012年第1期1卷 87-91页

作者： Jianfa Zhang Kevin F MacDonald nikolay I Zheludev Optoelectronics Research Centre&Centre for Photonic Metamaterials University of SouthamptonSouthamptonHampshire SO171BJUK

According to the fundamental Huygens superposition principle,light beams traveling in a linear medium will pass though one another without mutual ***,the field of photonics is based on the premise that controlling light signals with light requires intense laser fields to facilitate beam interactions in nonlinear media,where the superposition principle can be *** we challenge this wisdom and demonstrate that two coherent beams of light of arbitrarily low intensity can interact on a metamaterial layer of nanoscale thickness in such a way that one beam modulates the intensity of the *** show that the interference of beams can eliminate the plasmonic Joule losses of light energy in the metamaterial or,in contrast,can lead to almost total absorption of *** of this phenomenon may lie in ultrafast all-optical pulse-recovery devices,coherence filters and terahertz-bandwidth light-by-light modulators.

关键词： all-optical metamaterial plasmonic

Investigation into the operation of an autothermal two-section subbituminous coal fluidized bed gasifier

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International Journal of Coal Science & Technology 2023年第3期10卷 190-203页

作者： nikolay Abaimov Alexander Ryzhkov Alexey Dubinin Lu Ding Vladimir Tuponogov Sergey Alekseenko Ural Federal University EkaterinburgRussia 6200022 Institute of Clean Coal Technology East China University of Science and TechnologyShanghai 200237China Institute of Thermophysics Siberian BranchRussian Academy of SciencesNovosibirskRussia 630090

Using a newly developed experimental setup,the features and advantages of an autothermal single-casing atmospheric sub-bituminous coal fluidized bed air-blown gasifier,combining a combustion and gasification section,and mixing the dispersed phase(inert material,char)and heat exchange between them through an annular transfer device,have been *** increase the efficiency of the gasifier,an experimental-computational method was developed find the conditions for optimal operation,combining changing the annular flow's geometry and regulating the primary air for gasification.A simple and reliable multizone thermodynamic calculation model makes it possible to predict the composition of char and syngas in the gasification section with acceptable *** method confirmed that a two-section fluidized bed gasifier can provide efficient gasification of solid fuels and is suitable for use in small-scale cogeneration *** with a heating value of 3.6-4.5 MJ/m^(3)and CGE of 38.2%-42.3%was obtained in the experimental setup without optimizing the primary air flow *** optimization,the indicators increased to the heating value of syngas of 5.20-5.34 MJ/m^(3)and CGE of 42.5%-50.0%.With heat regeneration of 0.8,CGE increases to 70%.

关键词： Coal Syngas Gasification Bubbling fluidized bed Thermodynamics Modeling

Nonlinear dielectric optomechanical metamaterials

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Light(Science & Applications) 2013年第1期2卷 85-89页

作者： Jianfa Zhang Kevin F MacDonald nikolay I Zheludev Optoelectronics Research Centre&Centre for Photonic Metamaterials University of SouthamptonSO171BJUK Centre for Disruptive Photonic Technologies Nanyang Technological UniversitySingapore 637371

We introduce a dielectric photonic metamaterial presenting a giant nonlinear optical response driven by resonant optomechanical *** inherently free of Joule losses,it exhibits optical bistability at intensity levels of less than 0.2 mW mm22 and,furthermore,manifests nonlinear asymmetric transmission with a forward:backward optical extinction ratio of more than 30 dB.

关键词： Metamaterial optical bistability optomechanical

A New Species of Japalura(Agamidae: Lacertilia: Reptilia) from Central Highland,Vietnam

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Asian Herpetological Research 2017年第1期18卷 14-21页

作者： Natalia B.ANANJEVA nikolay L.ORLOV Tao Thien NGUYEN Department of Herpetology Zoological InstituteRussian Academy of Sciences Vietnam National Museum of Nature Vietnam Academy of Science and Technology

A new species of the agamid genus Japalura is described based on three specimens from southern part of Central Vietnam. It is distinguished from remaining congeners by the following combination of characters： adult size （SVL females 68-69 mm）, tail length/SVL ratio 226%-239%, HW/SVL ratio 17%-18%; FLL/SVL ratio 41%43%; HLL/SVL ratio 72%-73%; 7-9 supralabials, 7-9 infralabials, 54-56 middorsal scales, 20-22 lamellae under finger IV, 24-26 lamellae under toe IV, 1 scale between nasal and supralabials; tympanum concealed; absence of transverse gular fold. The geographical distribution of Japalura genus in general and of a new species in particular is discussed.

关键词： Agamidae Japalura taxonomy Vietnam description of a new species distribution