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Approach to the Theoretical Strength of Ti—Ni—Cu Alloy Nanocrystals by Grain Boundary Design

Journal of Materials Science & Technology 2015年第1期31卷 91-96页

作者： Alexandr M.Glezer Nadezhda A.Shurygina Elena N.Blinova Inga E.Permyakova se.ge. A.firstov Bardin Central Research Institute for the Iron and Steel Industry Vtoraya Baumanskaya ul.9/23Moscow 105005Russia Moscow State University of Instrumental Engineering and Information Science(MGUPI) Moscow 107996Russia National University of Science and Technology(MISIS) Moscow 119049Russia Frantsevich Institute of Materials Science Problems National Academy of Sciences of Ukraineul.Krzhizhanovskogo 3Kiev03680Ukraine

The grain boundary design was used to introduce boride Ti2B and TiB2nanoparticles of 5 nm in size into grain boundaries of nanocrystalline *** a result,the maximum normalized microhardness was increased by 20%and the theoretical limit of hardness is substantially *** is proposed that boride nanoparticles suppressed low-temperature grain-boundary sliding and,therefore,shifted the range of the anomalous behavior of Hall-Petch relation toward smaller sizes of the Ti-Ni-Cu nanocrystals.

关键词： Electron microscopy Microhardness Nanocrystal Nano

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semantic model and optimization of creative processes at mathematical knowledge formation

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Natural Science 2010年第8期2卷 915-922页

作者： Victor Egorovitch firstov 不详

The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications.

关键词： The Cybernetic Conception Optimization of Control Quantitative And Qualitative Information Measures Modelling Intellectual Systems Neural Network Mathematical Education The Control of Pedagogical Processes Creative Pedagogics Cognitive And Creative Processes Informal Axiomatic Thery semantic Net Net Optimization Parameters The Topology of semantic Net Metrization The System of Coverings Stochastic Model of Creative Processes At The Formation of Mathematical Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of The Creative Processes Control Interdisciplinary Learning: Colorimetric Barycenter

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Precise mode control of laser-written waveguides for broadband,low-dispersion 3D integrated optics

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Light(Science & Applications) 2024年第6期13卷 1186-1195页

作者： Yuying Wang Lijing Zhong Kuen Yao Lau Xuhu Han Yi Yang Jiacheng Hu se.ge. firstov Zhi Chen Zhijun Ma Limin Tong Kin seng Chiang Dezhi Tan Jianrong Qiu College of Optical Science and Engineering Zhejiang University310027HangzhouChina Institute of Light+X Science and Technology College of Information Science and EngineeringNingbo University315211NingboChina School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University215006SuzhouChina Prokhorov general Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center38 Vavilov str.Moscow119333Russia Zhejiang Lab 311121HangzhouChina College of Materials Science and Engineering Key Laboratory of Advanced Materials of Yunnan ProvinceKunming University of Science and Technology650093KunmingYunnanChina Department of Electrical Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARChina School of Materials Science and Engineering Zhejiang University310027HangzhouChina

Three-dimensional(3D)glass chips are promising waveguide platforms for building hybrid 3D photonic circuits due to their 3D topological capabilities,large transparent windows,and low coupling *** present,the key challenge in scaling down a benchtop optical system to a glass chip is the lack of precise methods for controlling the mode field and optical coupling of 3D waveguide ***,we propose an overlap-controlled multi-scan(OCMS)method based on laser-direct lithography that allows customizing the refractive index profile of 3D waveguides with high spatial precision in a variety of *** the basis of this method,we achieve variable mode-field distribution,robust and broadband coupling,and thereby demonstrate dispersionless LP21-mode conversion of supercontinuum pulses with the largest deviation ofges over conventional planar waveguide-optic platforms for on-chip transmission and manipulation of ultrashort laser pulses and broadband supercontinuum.

关键词： waveguide mode dispersion

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Impact of doping profiles on the formation of laser-active centers in bismuth-doped geO_(2)–SiO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： se.ge. ALYSHEV ALEXANDER VAKHRUSHEV ALEKSANDR KHEGAI ELENA firstovA KONSTANTIN RIUMKIN MIKHAIL MELKUMOV LYUDMILA ISKHAKOVA ANDREY UMNIKOV se.ge. firstov Prokhorov general Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,E-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

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generation of 1.3/1.4μm random fiber laser by bismuth-doped phosphosilicate fiber

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Chinese Optics Letters 2023年第7期21卷 35-38页

作者：王航贾文成姚永嘉杨欣芸 Mikhail Melkumov se.ge. firstov Alexey Lobanov 董志鹏罗正钱 Fujian Key Laboratory of Ultrafast Laser Technology and Applications School of Electronic Science and EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Prokhorov general Physics Institute Dianov Fiber Optics Research CenterRussian Academy of SciencesMoscow 119333Russia Devyatykh Institute of Chemistry of High-Purity Substances Russian Academy of SciencesNizhny Novgorod 603951Russia

We have successfully generated a 1.3/1.4μm random fiber laser(RFL)using bismuth(Bi)-doped phosphosilicate *** Bi-doped RFL has shown excellent long-term operational stability with a standard deviation of approximately 0.34%over 1 h at a maximum output power of 549.30 mW,with a slope efficiency of approximately 29.21%.The Bi-doped phosphosilicate fiber offers an emission spectrum ranging from 1.28 to 1.57μm,indicating that it can be tuned within this ***,we demonstrated a wavelength-tuning fiber laser with a wavelength of 1.3/1.4μm,achieved through the using of a fiber Bragg grating or a tunable *** to traditional laser sources,the RFL reduces the speckle contrast of images by 11.16%.Due to its high stability,compact size,and high efficiency,this RFL is highly promising for use in biomedical imaging,communication,and sensor applications.

关键词： random fiber laser bismuth-doped fiber wavelength tuning fiber laser

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Fluid Dynamic Response of the Russia seismically Differing Regions to the Global geodynamics Processes

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International Journal of geosciences 2012年第4期3卷 767-771页

作者： Valera P. Rudakov Pavel P. firstov Vladislav V. Tsyplakov Far Eastern Branch of Russian Academy of Sciences Russian Academy of Sciences

The results of the spectral-correlation analysis of the fluid-dynamic (radon and hydrogen) data monitoring obtained in the seismically active region—on Kamchatka and in conditions of Russian platform where compared to the results of the laser-deformometer measurements obtained on Caucasus. It allowed identify spectral components of the measured parameters, first of all, in the area of the lunar-solar tides. This identification have demonstrated the identical reaction of the mountain and platform regions to the global geodeformation processes of the tidal level and have shown the possibility of the measuring parameters response to the catastrophic events preparation processes. Really the prognostic effects in the investigated fields where indicated in periods of preparation and realization of the catastrophic earthquakes in Indian Ocean on December, 26, 2004 and on March, 28, 2005.

关键词： seismically Active Region Russian Platform Fluid-Dynamic Monitoring Global Processes

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