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Applied mathematics and mechanics(English Edition) 2020年第9期41卷 1359-1380页

作者： A.BEHRAVAN-RAD m.JAFARI Faculty of mechanical and mechatronics Engineering Shahrood University of TechnologyShahrood ***Iran

The main objective of this research is to investigate the hygroelastic behavior of a non-homogeneous circular plate made up of porous metamaterial resting on an auxetic material *** mechanical properties of the main plate,as well as moisture concentration,vary as an exponential function in the transverse ***’s ratio is *** elastic supporting medium is developed by considering the structurestructure *** on the linear hygroelasticity theory,the governing state equations in terms of displacements and moisture concentration are *** first,the Fickian equation is solved to compute the nonlinear distribution of moisture through the plate thickness,and then the state equations are semi-analytically solved using the statespace(SS)method and the differential quadrature(DQ)rule to predict the elastic field quantities.A comprehensive parametric analysis is accomplished to elucidate the effects of key parameters on the steady-state response of the plate under the mechanical and hygral loads.

关键词： metamaterial hygroelasticity auxeticity hygral interaction

Production of dimethylether(DmE) as a clean fuel using sonochemically prepared CuO and /or ZnO- modified γ- alumina catalysts

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燃料化学学报 2014年第3期42卷 350-356页

作者： Sameh m.K.Aboul-Fotouh Ain Shams University Faculty of EducationChemistry Department

The catalytic conversion of methanol to dimethylether(DmE)was studied over CuO/Al2O3,ZnO/Al2O3and ZnOCuO/Al2O3nanocatalysts prepared in presence or absence of ultrasonic *** catalysts were characterized by X-ray diffraction(XRD),surface characterization method(BET),scanning electron microscope(SEm),H2-temperature programmed reduction(H2-TPR)and temperature programmed desorption of ammonia(NH3-TPD).The experimental results show that during catalytic dehydration of methanol to dimethylether,the activities of the CuO/Al2O3,ZnO/Al2O3and ZnO-CuO/Al2O3catalysts prepared using ultrasonic treatment are much higher than those prepared in absence of *** shows that the use of ultrasonication results in much smaller *** and XRD show that the ultrasonication increases the surface area and pore volume of the catalysts.H2-TPR profiles indicated that reducibility of the sonicated nanocatalysts is carried out at lower ***3-TPD shows that ultrasound irradiation has enhanced the acidity of the nanocatalyst and hence enhanced catalytic performance for DmE formation.

关键词： DmE 燃料化学氧化铜氧化锌

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： N.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： Nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

Gd^(3+) ion induced UV upconversion emission and temperature sensing in Tm^(3+)/yb^(3+):y_(2)O_(3) phosphor

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Journal of Rare Earths 2023年第9期41卷 1295-1301,I0001页

作者： madan m.Upadhyay Kaushal Kumar Optical materials&Bio-imaging Research Laboratory Department of PhysicsIndian Institute of Technology(Indian School of Mines)Dhanbad-826004India

Cubic phase Tm^(3+)/yb^(3+):y_(2)O_(3) and Tm^(3+)/yb^(3+)/Gd^(3+):y_(2)O_(3) phosphors were prepared by low temperature combustion technique for upconversion emission in UV-visible *** 980 nm excitation has generated UV emission at 314 nm in tridoped phosphor due to the energy transfer from Tm^(3+) to Gd^(3+)*** emission bands from Tm^(3+) are also observed in both the *** coupled Stark sublevels ^(1)G_(4(a))(476 nm) and ^(1)G_(4(b))(488 nm) of Tm^(3+) ion were utilised for optical thermometry using fluorescent intensity ratio(FIR) *** result shows that maximum absolute sensitivity in tridoped phosphor is observed to be 1.33 × 10^(-3) K^(-1) at 298 ***,temperature rise of phosphor at various pump power densities was also measured and it is estimated to achieve 407 K at the pump power density of 38.46 W/cm^(2).

关键词： Upconversion UV emission Combustion synthesis Temperature sensing Optical heating Gd^(3+)emission

Chaos,Transport and mesh Convergence for Fluid mixing

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Acta mathematicae Applicatae Sinica 2008年第3期24卷 355-368页

作者： H. Lim y. yu J. Glimm X.L. Li D.H. Sharp Department of Applied mathematics and Statistics Stony Brook University Stony Brook NY 11794-3600 USA Computational Science Center Brookhaven National Laboratory Upton N~ 11793-6000 USA Los Alamos National Laboratory Los Alamos NM USA

Chaotic mixing of distinct fluids produces a convoluted structure to the interface separating these fluids. For miscible fluids （as considered here）, this interface is defined as a 50% mass concentration isosurface. For shock wave induced （Richtmyer-meshkov） instabilities, we find the interface to be increasingly complex as the computational mesh is refined. This interfacial chaos is cut off by viscosity, or by the computational mesh if the Kolmogorov scale is small relative to the mesh. In a regime of converged interface statistics, we then examine mixing, i.e. concentration statistics, regularized by mass diffusion. For Schmidt numbers significantly larger than unity, typical of a liquid or dense plasma, additional mesh refinement is normally needed to overcome numerical mass diffusion and to achieve a converged solution of the mixing problem. However, with the benefit of front tracking and with an algorithm that allows limited interface diffusion, we can assure convergence uniformly in the Schmidt number. We show that different solutions result from variation of the Schmidt number. We propose subgrid viscosity and mass diffusion parameterizations which might allow converged solutions at realistic grid levels.

关键词： Schmidt number mass diffusion turbulence multiphase flow

Creation of Super Long Transversely Polarized Optical Needle Using Azimuthally Polarized multi Gaussian Beam

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Chinese Physics Letters 2016年第6期33卷 29-32页

作者： C.m.Sundaram K.Prabakaran P.m.Anbarasan K.B.Rajesh A.m.musthafa Department of Physics Periyar University Department of Physics Mahendra Arts and Science College(Autonomous) Department of Physics Chikkanna Government Arts College Department of General Studies(Physics Group) Jubail University College(Male Branch)Royal Commission of Jubail

The intensity distribution in the focal region of a high-NA lens for the incident azimuthally polarized multi Gaussian beam transmitted through a multi belt spiral phase hologram is studied on the basis of the vector diffraction theory. Here we report a new method used to generate a needle of transversely polarized light beam with sub diffraction beam size of 0.366A that propagates without divergence over a long distance of about 22A in free space. We also expect that such a light needle of transversely polarized beam may find its applications in utilizing optical materials or instruments responsive to the transversal field only.

关键词： of on it for Creation of Super Long Transversely Polarized Optical Needle Using Azimuthally Polarized multi Gaussian Beam in that is

mapping non-laminar proton acceleration in laser-driven target normal sheath field

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High Power Laser Science and Engineering 2022年第1期10卷 10-16页

作者： C.y.Qin H.Zhang S.Li S.H.Zhai A.X.Li J.y.Qian J.y.Gui F.X.Wu Z.X.Zhang y.Xu X.y.Liang y.X.Leng B.F.Shen L.L.Ji R.X.Li State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Ultra-intense Laser Science Shanghai 201800China Department of Physics Shanghai Normal UniversityShanghai 200234China ShanghaiTech University Shanghai 201210China

We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum *** results illustrate the coexistence of ring-like and filamentation *** implement the knife edge method into the radiochromic film detector to map the accelerated beams,measuring a source size of 30-110μm for protons of more than 5 *** diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons,exhibiting non-laminar ***-in-cell simulations reproduced the experimental results,showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam *** work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.

关键词： knife-edge technique laser-plasma interaction non-laminar proton source target normal sheath acceleration Weibel instability

Experimental and numerical investigation of an intermediate temperature SOFC

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Experimental and numerical investigation of an intermediate ...

Fault Accommodation for a Class of Nonlinear Uncertain Systems With Event-Triggered Input

第九届全国氢能学术会议

作者： m.D.mat B.Timurkutluk y.Kaplan Nigde University

＜正＞There are large efforts in recent years to reduce the operation temperature of SOFCs which are usually employs yttria stabilized zirconia *** doped zirconia possesses high ionic conductivity below 700℃and has shown to have sufficient mechanical and long term *** this study,a large Scandia doped zirconia based electrolyte supported PEN is

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来源： cnki会议评论

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IEEE/CAA Journal of Automatica Sinica 2022年第2期9卷 235-245页

作者： Dong Zhao marios m.Polycarpou IEEE KIOS Research and Innovation Center of Excellence and the Department of Electrical and Computer EngineeringUniversity of CyprusNicosia 1678Cyprus

The event-triggered fault accommodation problem for a class of nonlinear uncertain systems is considered in this *** control signal transmission from the controller to the system is determined by an event-triggering scheme with relative and constant triggering *** the event-induced control input error and system fault threat,a novel eventtriggered active fault accommodation scheme is designed,which consists of an event-triggered nominal controller for the time period before detecting the occurrence of faults and an adaptive approximation based event-triggered fault accommodation scheme for handling the unknown faults after detecting the occurrence of *** closed-loop stability and inter-event time of the proposed fault accommodation scheme are rigorously *** cases for the fault accommodation design under constant triggering threshold are also *** example is employed to illustrate the effectiveness of the proposed fault accommodation scheme.

关键词： Adaptive control event-triggered control fault accommodation neural networks nonlinear systems

THE EFFECT OF EDIBLE BLACK TREE FUNGUS (AURICUARIA AURICULA) ON EXPERImENTAL ATHEROSCLEROSIS IN RABBITS

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中华医学杂志(英文版) 1989年第2期102卷 105-105页

作者： y m Fan m y Xu L y Wang y Zhang L Zhang H yang P Wang P Cui Laboratory of Atherosclerosis Beijing Heart Lung and Blood Vessel Medical Center Beijing

The effects of edible black tree fungus (BFF) compared with aspirin on serum lipid level and experimental atherosclerosis and thrombosis in rabbits were studied. The results showed that total serum cholesterol and B-lipoprotein of the BTF group were significantly decreased (Pmyocardial arterial lumen stenosis in the BTF group. The development of thrombus and platelet aggregation and thromboxane TXB2 level were inhibited both in the BTF and aspirin group (Pmay be used as a healthy food in preventing atherosclerosis and coronary heart disease, but its mechanism requires further investigation.

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