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4阶非线性薛定谔方程解的渐近行为（英文）

数学进展 2017年第6期46卷 801-818页

作者：林仲夫 pavel i.naumkin 大阪大学理学研究生院数学系墨西哥国立自治大学莫雷利亚校区数学科学中心

本文综述了具有幂次非线性或耗散形式的非线性4阶薛定谔方程小振幅解的全局存在性和渐近行为的一些最新研究结果.考虑了散射问题的超临界非线性和临界非线性情况.

关键词： 4阶非线性薛定谔方程大时间渐进性临界非线性

Numerical investigation of full scale coaxial main rotor aerodynamics in hover and vertical descent

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Chinese Journal of Aeronautics 2021年第5期34卷 666-683页

作者： pavel V.MAKEEV Yuri M.iGNATKiN Alexander i.SHOMOV Department of Helicopter Design Moscow Aviation Institute(National Research University)Moscow 125993Russia

The original free vortex wake model was used for numerical *** of the aerodynamic characteristics in hover and vertical descent modes in the range of vertical descent speed of 0–30 m/s including the Vortex Ring State(VRS)area was *** calculations were carried out under the condition of variable blade pitch angle values providing a fixed timeaverage thrust *** data of free vortex wake shapes,flow structures,and velocity fields were obtained and *** time-dependences of the rotor’s thrust and torque coefficients were obtained and *** obtained data allows determining the boundaries of the VRS area by various criteria such as rotor thrust and torque pulsations,growth of rotor power consumption relative to the hover,growth of rotor induced velocities relative to the hover,and growth of the required rotor blade pitch angles *** results of the study are compared with experimental and calculated data of other authors and can significantly supplement the available results of experimental and computational studies in this area.

关键词： Aerodynamic characteristics Coaxial rotor Free wake model Hover and vertical descent Vortex ring state mode

Plasmon-assisted optical trapping and anti-trapping

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Light(Science & Applications) 2016年第1期5卷 52-57页

作者： Aliaksandra ivinskaya Mihail i Petrov Andrey A Bogdanov ivan Shishkin pavel Ginzburg Alexander S Shalin Department of Nanophotonics and Metamaterials ITMO UniversityBirzhevaja Line14199034 St PetersburgRussia School of Electrical Engineering Tel Aviv UniversityRamat AvivTel Aviv 69978Israel Kotel’nikov institute of Radio Engineering and Electronics of Russian Academy of Sciences(Ulyanovsk branch) Goncharova Street 48/2432071 UlyanovskRussia Ulyanovsk State University Lev Tolstoy Street 42432017 UlyanovskRussia

The ability to manipulate small objects with focused laser beams has opened a venue for investigating dynamical phenomena relevant to both fundamental and applied *** and plasmonic structures enable superior performance in optical trapping via highly confined *** this case,the interplay between the excitation field,re-scattered fields and the eigenmodes of a structure can lead to remarkable effects;one such effect,as reported here,is particle trapping by laser light in a vicinity of metal *** plasmon excitation at the metal substrate plays a key role in tailoring the optical forces acting on a nearby *** on whether the illuminating Gaussian beam is focused above or below the metal-dielectric interface,an order-of-magnitude enhancement or reduction of the trap stiffness is achieved compared with that of standard glass ***,a novel plasmon-assisted anti-trapping effect(particle repulsion from the beam axis)is predicted and studied.A highly accurate particle sorting scheme based on the new anti-trapping effect is *** ability to distinguish and configure various electromagnetic channels through the developed analytical theory provides guidelines for designing auxiliary nanostructures and achieving ultimate control over mechanical motion at the microand nano-scales.

关键词： Gaussian beam Green’s function optical forces optical tweezers surface plasmon

Patterning Nanoroads and Quantum Dots on Fluorinated Graphene

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Nano Research 2011年第1期4卷 143-152页

作者： Morgana A. Ribas Abhishek K. Singh pavel B. Sorokin Boris i. Yakobson Department of Mechanical Engineering and Materials Science and Department of Chemistry Rice University Houston Texas 77005 USA Materials Research Centre Indian Institlzte of Science Bangalore 560012 India

Using ab initio methods we have investigated the fluorination of graphene and find that different stoichiometric phases can be formed without a nucleation barrier, with the complete ＂2D-Teflon＂ CF phase being thermody- namically most stable. The fluorinated graphene is an insulator and turns out to be a perfect matrix-host for patterning nanoroads and quantum dots of pristine graphene. The electronic and magnetic properties of the nanoroads can be tuned by varying the edge orientation and width. The energy gaps between the highest occupied and lowest unoccupied molecular orbitals （HOMO-LUMO） of quantum dots are size-dependent and show a confinement typical of Dirac fermions. Furthermore, we study the effect of different basic coverage of F on graphene （with stoichiometries CF and C4F） on the band gaps, and show the suitability of these materials to host quantum dots of graphene with unique electronic properties.

关键词： Graphene fluorinated graphene fluorographene nanoroads quantum dots

Selected aspects of dielectric behavior of plasma sprayed titanates

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Journal of Advanced Ceramics 2012年第1期1卷 50-59页

作者： pavel CTiBOR Josef SEDLACEK institute of Plasma Physics ASCRv.v.i.Za Slovankou 3PragueCzech Republic Department of Electrotechnology Faculty of Electrical EngineeringCzech Technical UniversityTechnicka 2PragueCzech Republic

XRD measurements were carried out on plasma sprayed titanates BaTiO_(3),CaTiO_(3),MgTiO_(3)and a mixture of the last *** were tested as dielectrics and volume resistivities of the materials were also *** microscopy was used for mapping of the dielectric response of selected *** results show differences in the crystal structure between plasma sprayed coatings and feedstock powders in the case of BaTiO_(3)and MgTiO_(3)whereas CaTiO_(3)is crystalograffically identical with its *** reason can be found in larger sensitivity of BaTiO_(3)and MgTiO_(3)to the reductive conditions at plasma spraying whereas CaTiO_(3)seems to be rather inert from this *** CaTiO_(3)exhibits anomalous dielectric losses because of intrinsic conductivity.

关键词： plasma spraying dielectric properties electrical properties BaTiO3 and titanates capacitors

Assessment of the thermal effect of large industrial buildings on permafrost foundation soils in Yakutsk

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Research in Cold and Arid Regions 2023年第6期15卷 262-267页

作者： Rudolf V.Zhang Stanislav i.Zabolotnik pavel S.Zabolotnik Melnikov Permafrost institute SB RAS Yakutsk 677010Russia

The results of monitoring studies of the ground thermal state beneath the Yakutsk Combined Heat and Power Plant buildings are presented in order to determine their structural stability and the possibility of further troublefree operation of the entire complex of the *** main causes for the formation of water-bearing taliks under and adjacent to the buildings are presented,and the factors influencing the existing geocryological situation are *** continuing stable state of the buildings demonstrates the possibility of using two construction principles on permafrost at one site,including preserving permafrost and accommodating permafrost thawing.

关键词： Yakutsk Combined Heat and Power Plant Permafrost Talik Ground temperature

Analysis of the Caratheodory's Theorem on Dynamical System Trajectories Under Numerical Uncertainty

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iEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 787-793页

作者： pavel Osinenko Grigory Devadze Stefan Streif Automatic Control and System Dynamics Laboratory Technische Universitat Chemnitz09107 ChemnitzGermany iEEE

The current work proposes a new and constructive proof for the Caratheodory's theorem on existence and uniqueness of trajectories of dynamical systems. The key concern is the numerical uncertainty, i.e., the discrepancy between mathematical proofs, algorithms, and their implementations, which may affect the correct functioning of a control system. Due to growing demands on security and compliance with specifications,correctness of the control system functioning is becoming ever more important. Since in both dynamical systems and many control design approaches, one of the central notions is the system trajectory, it is important to address existence and uniqueness of system trajectories in a way which incorporates numerical uncertainty. Constructive analysis is a particular approach to formalizing numerical uncertainty and is used as the basis of the current work. The major difficulties of guaranteeing existence and uniqueness of system trajectories arise in the case of systems and controllers which possess discontinuities in time,since classical solutions to initial value problems do not *** issue is addressed in Caratheodory's theorem. A particular constructive variant of the theorem is proven which covers a large class of problems found in practice.

关键词： Constructive analysis Caratheodory’s theorem dynamical systems

Coalification and coal alteration under mild thermal conditions

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international Journal of Coal Science & Technology 2018年第3期5卷 358-373页

作者： pavel Straka ivana Sykorova institute of Rock Structure and Mechanics v.v.i The Czech Academy of Sciences V Holegovickach 41 18209 Prague 8Czech Republic

Coalification temperatures are often considered to be approximately 100-170 ℃ for bituminous coal and 170-275 ℃ for anthracite. However, our micropetrographic observations, solid state ^27Al magic-angle spinning nuclear magnetic resonance measurements, interpretation of δ^13C values for whewellite in pelosiderite concretions from Carboniferous sediments, and assessment of whewellite thermal stability show that coalification temperatures can be significantly lower. Also the temperatures of coal alteration may be substantially lower than is stated. Ordinarily, high- temperature alteration is reported, but microthermometric measurements of fluids temperatures and micropetrographic observations show that the coal alteration can take place at low temperatures. For this reason, coals from the Kladno- Rakovnik Basin, part of Late Paleozoic continental basins of the Czech Republic, were analyzed. Regarding coalification, micropetrographic characterizations of unaltered coals, the presence of thermally unstable Al complexes in the coal organic mass documented using ^27Al MAS NMR method, and proven occurrence of whewellite in pelosiderite concretions suggest a lower coalification temperature, max. -70 ℃. Regarding coal alteration, micropetrographic observations revealed （a） the weaker intensity of fluorescence of liptinite, （b） mylonitic structures and microbreccia with carbonate fluid penetration, and （c） high oxygen content in coals （37-38 wt.%）. These phenomena are typical for thermal and oxidative alteration of coal. As the temperature of carbonate fluids inferred from fluid inclusion analysis was evaluated as -100-113 ℃, the temperature of coal alteration was suggested as -113℃; the alteration was caused by hot hydrothermal fluids.

关键词： Coalification Thermal and oxidative alteration Kladno-Rakovn Basin - Al complexes ^27Al MAS NMR Fluid inclusions δ^13C Whewellite

Structural and photocatalytic characteristics of TiO_(2) coatings produced by various thermal spray techniques

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Journal of Advanced Ceramics 2013年第3期2卷 218-226页

作者： pavel CTiBOR Vaclav STENGL Zdenek PALA institute of Plasma Physics ASCRv.v.i.Za Slovankou 3PragueCzech Republic institute of inorganic Chemistry ASCRv.v.i.Husinec-RezCzech Republic

Titanium dioxide(TiO_(2))was elaborated by four different thermal spray techniques-(i)plasma spraying using a water-stabilized torch,(ii)plasma spraying using a gas-stabilized torch,(iii)high velocity oxy-fuel gun,and(iv)oxy-acetylene *** porosity of the coatings was studied by optical microscopy,nano-structural features by scanning electron microscopy(SEM),phase composition by X-ray diffraction(XRD);the microhardness,surface roughness and wear resistance were *** diffuse reflectance was measured by ultra-violet/visible/near-infrared(UV/Vis/NiR)scanning *** kinetics of photocatalytic degradation of gaseous acetone was measured under a UV lamp with 365 nm *** all the applied spray processes,the transformation of anatase phase from the initial powders to rutile phase in the coatings *** spite of this transformation,all the coatings exhibited certain photocatalytic activity,which correlated well with their band gap energy calculated from *** the coatings offer relatively good mechanical properties and can serve as robust photocatalysts.

关键词： plasma spraying high velocity oxy-fuel(HVOF)spraying flame spraying titanium dioxide(TiO_(2)) photocatalysis band gap