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Mechanical and thermal postbuckling of FGM thick circular cylindrical shells reinforced by FGM stiffener system using higher-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第1期38卷 73-98页

作者： d.v.dUNG H.T.THIEM Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam

The postbuckling of the eccentrically stiffened circular cylindrical shells made of functionally graded materials （FGMs）, subjected to the axial compressive load and external uniform pressure and filled inside by the elastic foundations in the thermal environments, is investigated with an analytical method. The shells are reinforced by FGM stringers and rings. The thermal elements of the shells and stiffeners in the fundamental equations are considered. The equilibrium and nonlinear stability equations in terms of the displacement components for the stiffened shells are derived with the third-order shear deformation theory and Leckhniskii smeared stiffener technique. The closed-form expressions for determining the buckling load and postbuckling load-deflection curves are obtained with the Galerkin method. The effects of the stiffeners, the foundations, the material and dimensional parameters, and the pre-existent axial compressive and thermal load are considered.

关键词： stiffened cylindrical shell functionally graded material (FGM) postbuck- ling elastic foundation analytical

Nonlinear analysis on dynamic buckling of eccentrically stiffened functionally graded material toroidal shell segment surrounded by elastic foundations in thermal environment and under time-dependent torsional loads

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Applied Mathematics and Mechanics(English Edition) 2016年第7期37卷 835-860页

作者： d.v.dUNG P.M.vUONG department of Mathematics Mechanics and InformaticsVietnam National University Faculty of Civil and Industrial National University of Civil Engineering

The nonlinear analysis with an analytical approach on dynamic torsional buckling of stiffened functionally graded thin toroidal shell segments is investigated. The shell is reinforced by inside stiffeners and surrounded by elastic foundations in a thermal environment and under a time-dependent torsional load. The governing equations are derived based on the donnell shell theory with the yon Karman geometrical nonlinearity, the Stein and McElman assumption, the smeared stiffeners technique, and the Galerkin method. A deflection function with three terms is chosen. The thermal parameters of the uniform temperature rise and nonlinear temperature conduction law are found in an explicit form. A closed-form expression for determining the static critical torsional load is obtained. A critical dynamic torsional load is found by the fourth-order Runge-Kutta method and the Budiansky-Roth criterion. The effects of stiffeners, foundations, material, and dimensional parameters on dynamic responses of shells are considered.

关键词： toroidal shell segment functionally graded material (FGM) stiffened shell,critical static and dynamic torsional load thermal environment

Synthesis of RE-Ag,Al-RE-doped sol-gel glass and films for solar cells

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Journal of Rare Earths 2009年第4期27卷 671-674页

作者： A.v.Semchenko v.v.Sidsky v.Е.Gaishun d.L.Kovalenko W.Strek Francisk Skorina Gomel State University 246019 Sovetskaya st.104 Gomel Belarus Institute of Low Temperature and Structures Research PAN Okolna st.2 Wroclaw Poland

The paper dealt with the study of fluorescence properties of sol-gel systems doped with rate-earth ions and co-doped with silver. The general problem for these types of inorganic phosphors was a very low absorbance in the visible range. Therefore, a sensitizer of luminescence of the rare-earth ions should be selected and used. The sensitizer should possess a good absorbance in the visible range and strong interaction with the rare-earth ions. In this study silver ions were selected as the sensitizer.

关键词： sol-gel method sol-gel glass and film luminescence and its amplification rare-earth ions silver ions energy transfer

dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo Flores Leonardo Aguilar-Hernández Fernado García-dolores Humberto Nicolini Andrea Judith vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

Numerical and Experimental Studies of Working Processesin a Cryogenic Fuelling Tank Coupled with Energy Plant

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Journal of Thermal Science 2024年第6期33卷 2190-2202页

作者： UGLANOv d.A. SHIMANOvA A.B. SHIMANOv A.A. BLAGIN E.v. SARMIN d.v. LIU Junjie ZHENG Guanghua Cryogenics Laboratory Samara UniversitySamara 443086Russian Federation School of Power and Energy Northwestern Polytechnical UniversityXi'an 710129China

This article presents a d.vice for the storage and gasification of cryogenic working fluid,which is named a cryogenic fuelling tank.A cryogenic fuel tank can serve both as a fuel vessel and a pressure accumulator due to the regasification process that takes place *** of this tank is slowed by the lack of theoretical and experimental research on its working *** article deals with an investigation of the working process of the energy plant based on a cryogenic fuel tank coupled with a rotor-vane *** mathematical models include evaporation and condensation processes within the tank,heat exchange between gas chambers and between the tank and environment,and changes in energy due to incoming and leaving *** work used to determine the efficiency of a power plant is generated by a steam *** shows that it is possible to achieve specific work outputs up to 110-160 kJ/kg with relative d.viation of power and specific work determination equal to 1.4% and 1.9%correspondingly.

关键词： cryogenic fuelling tank gasification liquid natural gas low-temperature energy plant

Effect of hydrogen plasma treatment on the growth and microstructures of multiwalled carbon nanotubes

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Nano-Micro Letters 2010年第1期2卷 42-48页

作者： S.K.Srivastava v.d.vankar v.Kumar department of Physics Indian Institute of Technology Delhi National Physical Laboratory Dr.K.S.Krishnan Marg

The effect of hydrogen plasma treatment of iron oxide films on the growth and microstructure of carbon nanotubes(CNTs)by microwave plasma enhanced chemical vapor deposition process has been *** plasma was characterized in-situ using optical emission *** of the films was examined by scanning electron *** analysis was carried out by high resolution transmission electron microscopy(HRTEM)equipped with energy dispersive X-ray spectroscopy(EdS)and micro-diffraction *** is found that oxide films without H_2 plasma pretreatment or treated for lesser time resulted in CNT films with high percentage of carbonaceous particles and with embedded particles/nanorods distributed discontinuously in the cavity of the *** embedded particles were found to be of iron carbide(Fe-C)as confirmed by HRTEM,EdS and micro-diffraction *** observations suggested that the iron oxide particles had poor catalytic action for CNT growth and in-situ reduction of oxide clusters to Fe by hydrogen plasma plays a key role in discontinuous filling of the nanotubes by the catalytic particles.

关键词： Carbon nanotubes Chemical vapor deposition Iron carbide MPECvd

Broadband ferromagnetic resonance studies on influence of interface bonding on magnetoeletric effects in ferrit e-ferroelectric composites

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Frontiers of physics 2012年第4期7卷 418-423页

作者： d.v.B.Murthy Gopalan Srinivasan Physics department Oakland UniversityRochesterMI 48309USA

A systematic study has been carried out on the effects of interface bonding on the strain mediated magnetoelectric （ME） coupling in ferromagnetic-ferroelectric bilayers. The technique used involves the static electric field E tuning of the ferromagnetic resonance （FMR） in yttrium iron garnet （YIG） and lead zirconate titanate （PZT） or lead magnesium niobate-lead titanate （PMN-PT）. A broad band detection technique has been d.veloped for studies over 1 40 GHz in three types of bilayers： epoxy bonded, eutectic bonded and YIG films directly grown onto piezoelectric substrate by electrophoretic deposition. The strength A of the converse ME effect （CME） defined as the ratio of the frequency shift 8f in FMR in E, A = 8f/E, varies over the range 0.8 to 4.3 ***/kv, and is the highest for eutectic bonded samples and is the weakest for epoxy bonded bilayers. The results presented here as of importance for dual electric and magnetic field tunable ferrite ferroelectric microwave resonators and filters.

关键词： Keywords ferrite ferroelectric magnetoelectric ferromagnetic resonance

Evolution of ionization waves in a multi-pulsed plasma jet:the role of memory charges

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Plasma Science and Technology 2023年第3期25卷 95-103页

作者： N Yu BABAEvA G v NAIdIS v F TARASENKO d A SOROKIN Cheng ZHANG Tao SHAO Joint Institute for High Temperatures Russian Academy of Sciences Institute of High Current Electronics Siberian BranchRussian Academy of Sciences Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

In this paper,we discuss the properties of ionization waves(IWs)in a multi-pulsed plasma jet while using the two-dimensional computational *** IWs are generated by application of three short negative pulses with a repetition frequency 12.5 *** simulations are performed continuously during a single run while accounting for charges accumulated inside(surface charges)and outside(space charges)the *** plasma forming gas mixture(He/O2=99.8%/0.2%)is injected through the discharge tube into the surrounding humid *** show that an IW can emerge from the tube exit at a pulse rising edge(as a negative IW)and at a falling edge of the same pulse(as a positive IW).It is demonstrated that remnants of the negative and positive charges play an essential role in the discharge *** first pulse travels the shortest distance as it propagates through the initially non-ionized *** IWs d.veloping during the second pulse essentially enlarge the plasma plume *** the same time,the IWs generated by the third pulse eventually decay due to the remnants of charges accumulated during the previous *** memory charges can lead to the IW extinction.

关键词： helium plasma jet multiple pulses positive and negative ionization waves

Second-Harmonic Response in Magnetic Nodal-Line Semimetal Fe_(3)GeTe_(2)

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Chinese Physics Letters 2022年第9期39卷 62-66页

作者： v.d.Esin A.A.Avakyants A.v.Timonina N.N.Kolesnikov E.v.d.viatov Institute of Solid State Physics of the Russian Academy of Sciences ChernogolovkaMoscow District2 Academician Ossipyan Str.142432Russia

We experimentally investigate second-harmonic transverse voltage response to ac electrical current for a magnetic nodal-line semimetal Fe_(3)GeTe_(2)(FGT).For zero magnetic field,the observed second-harmonic voltage behaves as a square of the longitudinal current,as it should be expected for nonlinear Hall *** magnetic field behavior is found to be sophisticated:while the first-harmonic response shows the known anomalous Hall hysteresis in FGT,the second-harmonic Hall voltage is characterized by the pronounced high-field hysteresis and flat(B-independent)region with curves touching at low *** high-field hysteresis strongly depends on the magnetic field sweep rate,so it reflects some slow relaxation *** the lowest rates,it is also accomplished by multiple crossing *** shape of the second-harmonic hysteresis is known for skyrmion spin textures in nonlinear *** skyrmions have been demonstrated for FGT by direct visualization techniques,we can connect the observed high-field relaxation with deformation of the skyrmion ***,the second-harmonic Hall voltage response can be regarded as a tool to detect spin textures in transport experiments.

关键词： harmonic relaxation hysteresis