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Guiding of Waves between Absorbing Walls

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Journal of Modern Physics 2012年第7期3卷 553-560页

作者： dmitrii kouznetsov Makoto Morinaga Institute for Laser Science University of Electro-Communications 1-5-1 Chofugaoka Chofu Tokyo Japan

Guiding of waves between parallel absorbing walls is considered. The principal mode is constructed;its absorption is estimated. The agreement with previous results about reflection of waves from absorbing walls is discussed. Roughly, the effective absorption of the principal mode is proportional the minus third power of the distance between walls, minus 1.5 d power of the wavenumber and minus 0.5 power of the local absorption of the wave in the wall. This estimate is suggested as hint for the design of the atomic waveguides, and also as tool for optimization of attenuation of the amplified spontaneous emission (and suppression of parasitic oscillations) in high power lasers.

关键词： Zeno Effect Atom Optics Waveguides Suppression of Amplified Spontaneous Emission

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

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刀具磨损和变摩擦系数对切削力的影响

光学精密工程 2024年第14期32卷 2211-2224页

作者：郐吉才段云乾李新刘石安 ARDASHEV dmitrii Valerievich 河南理工大学机械与动力工程学院河南焦作454003 河南省先进电子封装材料精密成形国际联合实验室河南焦作454003 南乌拉尔国立大学俄罗斯车里雅宾斯克454080

刀具磨损和摩擦系数对切削力、表面质量有显著影响。为进一步研究刀具磨损和摩擦系数对切削力的影响规律,提出了同时考虑刀具磨损和变摩擦系数的切削力模型。首先分析了刀具磨损对刃口半径的影响规律,指出随刀具磨损增加,刃口半径增加;... 详细信息

刀具磨损和摩擦系数对切削力、表面质量有显著影响。为进一步研究刀具磨损和摩擦系数对切削力的影响规律,提出了同时考虑刀具磨损和变摩擦系数的切削力模型。首先分析了刀具磨损对刃口半径的影响规律,指出随刀具磨损增加,刃口半径增加;其次明确了刀具磨损及刃口半径对最小切削厚度的影响规律,认为最小切削厚度随刀具磨损、刃口半径的增加而增加。进一步用单晶金刚石刀具切削铝合金,并在切削深度、进给速度、刀具刃口半径、刀具磨损宽度以及恒定摩擦系数与变摩擦系数等方面进行了对比。研究表明,随切削深度、进给速度增加,法向切削力与切向切削力增加;随刃口半径从150 nm增加到450 nm,切向力增加了1.13倍,法向力增加了2.12倍;随刀具磨损宽度从0增加到0.55μm,切向力增加了1倍,法向力增加了约7倍;恒定摩擦系数切削力最大误差高达41%,变摩擦系数切削力最大误差在11%以内。因此,同时考虑了刀具磨损与变摩擦系数的切削模型与实际切削过程更加吻合。

关键词：切削力模型刀具磨损变摩擦系数金刚石刀具

Guiding of Waves between Absorbing Walls

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Journal of Modern Physics（现代物理） 2012年第7期

作者： dmitrii kouznetsov Makoto Morinaga

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狐獴王朝雌性首领统治下的毒物克星

环球人文地理 2024年第7期 70-77页

作者：鲨鲨 Ondrejprosicky Kim Honza Hejda Christian dmitrii Potashkin __Sourire Giamplume YOSHIDA Andra ali

为了保持绝对的女王地位，狐獴不惜残害同胞，杀死幼崽，在种群内部时刻上演着“宫心计”。在非洲西南部的卡拉哈里沙漠，太阳炙烤着大地，无数生灵在这里繁衍生息，遵循的都是弱肉强食的法则。而散布在广袤沙漠里的狐獴，体型小巧，长...

为了保持绝对的女王地位，狐獴不惜残害同胞，杀死幼崽，在种群内部时刻上演着“宫心计”。在非洲西南部的卡拉哈里沙漠，太阳炙烤着大地，无数生灵在这里繁衍生息，遵循的都是弱肉强食的法则。而散布在广袤沙漠里的狐獴，体型小巧，长相呆萌，一度登上网友票选的“世界上最可爱物种”排行榜。实际上，狐獴的战斗力不容小觑，可爱外表下或许拥有的是凶残的内心，它们以十分惊人的生存本领，在沙漠上构筑起自己的王国。

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An advanced theoretical approach to study super-multiperiod superlattices:theory vs experiments

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Journal of Semiconductors 2024年第2期45卷 57-66页

作者： Alexander Sergeevich Dashkov Semyon Andreevich Khakhulin dmitrii Alekseevich Shapran Gennadii Fedorovich Glinskii Nikita Andreevich Kostromin Alexander Leonidovich Vasiliev Sergey Nikolayevich Yakunin Oleg Sergeevich Komkov Evgeniy Viktorovich Pirogov Maxim Sergeevich Sobolev Leonid Ivanovich Goray Alexei Dmitrievich Bouravleuv Saint-Petersburg Electrotechnical University"LETI" Saint Petersburg197022Russian Federation Alferov Saint-Petersburg National Research Academic University of the Russian Academy of Sciences Saint Petersburg194021RussiaFne deration Saint Petersburg Polytechnic University of Peter the Great Saint Petersburg195251Russian Federation Shubnikov Institute of Crystallography of Federal Scientific Research Centre“Crystallography and Photonics” Russian Academy of SciencesMoscow119333Russian Federation National Research Center‘Kurchatov Institute’ Moscow123182Russian Federation University associated with IA EAEC Saint Petersburg194044Russian Federation Institute for Analytical Instrumentation Saint Petersburg198095Russian Federation Ioffe Institute Saint Petersburg194021Russian Federation

A new theoretical method to study super-multiperiod superlattices has been *** method combines the precision of the 8-band kp-method with the flexibility of the shooting method and the Monte Carlo *** method was applied to examine the finest quality samples of super-multiperiod Al_(0.3)Ga_(0.7)As/GaAs superlattices grown by molecular beam *** express photoreflectance spectroscopy method was utilized to validate the proposed theoretical *** the first time,the accurate theoretical analysis of the energy band diagram of super-multiperiod superlattices with experimental verification has been *** proposed approach highly accurately determines transition peak positions and enables the calculation of the energy band diagram,transition energies,relaxation rates,and gain *** has achieved a remarkably low 5%error compared to the commonly used method,which typically results in a 25%error,and allowed to recover the superlattice *** retrieved intrinsic parameters of the samples aligned with XRD data and growth *** proposed method also accurately predicted the escape of the second energy level for quantum well thicknesses less than 5 nm,as was observed in photoreflectance *** new designs of THz light-emitting devices operating at room temperature were suggested by the developed method.

关键词： super-multiperiod superlattice photoreflectance spectroscopy Kane model kp-method energy band diagram light amplifiers

Review of the relativistic magnetron

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Matter and Radiation at Extremes 2019年第6期4卷 44-62页

作者： dmitrii Andreev Artem Kuskov Edl Schamiloglu Department of Electrical and Computer Engineering University of New MexicoAlbuquerqueNew Mexico 87131-0001USA

The cavity magnetron is the most compact,efficient source of high-power microwave(HPM)*** imprint that the magnetron has had on the world is comparable to the invention of the nuclear ***-and low-power magnetrons are used in many applications,such as radar systems,plasma generation for semiconductor processing,and—the most common—microwave ovens for personal and industrial *** the invention of the magnetron in 1921 by Hull,scientists and engineers have improved and optimized magnetron technology by altering the geometry,materials,and operating conditions,as well as by identifying applications.A major step in advancing magnetrons was the relativistic magnetron introduced by Bekefi and Orzechowski at MIT(USA,1976),followed by the invention of the relativistic magnetron with diffraction output(MDO)by Kovalev and Fuks at the Institute of Applied Physics(Soviet Union,1977).The performance of relativistic magnetrons did not advance significantly thereafter until researchers at the University of Michigan and University of New Mexico(UNM)independently introduced new priming techniques and new cathode topologies in the 2000s,and researchers in Japan identified a flaw in the original Soviet MDO ***,the efficiency of the MDO has reached 92%with the introduction of a virtual cathode and magnetic mirror,proposed by Fuks and Schamiloglu at UNM(2018).This article presents a historical review of the progression of the magnetron from a device intended to operate as a high-voltage switch controlled by the magnetic field that Hull published in 1921,to the most compact and efficientHPMsource in the twenty-first century.

关键词： relativistic microwave mirror

Electron–plasmon and electron–magnon scattering in ferromagnets from first principles by combining GW and GT self-energies

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npj Computational Materials 2021年第1期7卷 1619-1632页

作者： dmitrii Nabok Stefan Blügel Christoph Friedrich Peter Grünberg Institut and Institut for Advanced Simulation Forschungszentrum JülichJülich 52425Germany

This work combines two powerful self-energy techniques:the well-known GW method and a self-energy recently developed by us that describes renormalization effects caused by the scattering of electrons with magnons and Stoner *** GT selfenergy,which is fully k-dependent and contains infinitely many spin-flip ladder diagrams,was shown to have a profound impact on the electronic band structure of Fe,Co,and *** the present work,we refine the method by combining GT with the GW *** resulting GWT spectral functions exhibit strong lifetime effects and emergent dispersion *** are in an overall better agreement with experimental spectra than those obtained with GW or GT alone,even showing partial improvements over local-spin-density approximation dynamical mean-field *** performed analysis provides a basis for applying the GWT technique to a wider class of magnetic materials.

关键词： materials theory infinitely

Quantum fluids in nanoporous media——Effects of the confinement and fractal geometry

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Chinese Science Bulletin 2011年第34期56卷 3617-3622页

作者： TAYURSKII dmitrii LYSOGORSKIY Yury Department of Physics Kazan Federal University

The complex behavior of such quantum fluids like liquid 4He and liquid 3He in nanoporous media is determined by spatial quantization because of geometrical confinement as well as by significant contribution from the surface atoms. In the present report we will review the procedure, results and discuss the issues for fractionalized nonextensive hydrodynamical approach to describe the properties of quantum fluids inside nanopores and propose consideration of strong correlated quantum liquid by means of fractionalized Schro¨dinger equation.

关键词：量子流体多孔介质分形几何薛定谔方程复杂行为报告审查力学方法量子液体