Dielectric Response
Mostrando 1-12 de 34 artigos, teses e dissertações.
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1. A Physical Study to Explain Response Differences between the BID and FID Detectors for PAHs and Pesticides
The dielectric barrier discharge ionization detector (BID) is one of the most modern detectors commercially available for gas chromatography (GC). Its technology based on the sample ionization through the energy released from the helium plasma generation process gives it the ability to act as a universal detector and a greater response to various types of co
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Ground-Penetrating Radar Antenna Design for Homogeneous and Low-Loss Dielectric Multilayer Media
Abstract Non-destructive evaluation of multilayer media represents an electromagnetic inverse problem, usually solved with analysis techniques in the time and frequency domains. The time- domain analysis technique depends directly on the accurate detection of reflected peaks measured by ground-penetrating radar (GPR), which limits this technique when the ref
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-06
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3. Theoretical Study of Plasmonically Induced Transparency Effect in Arrays of Graphene-Based Double Disk Resonators
Abstract In this paper, we consider coupled disk-shaped resonators separated by a thin dielectric substrate that can be used as frequency-tunable filters or as electromagnetic switches in the terahertz frequency band. The two disks are electromagnetically coupled and resonate with dipole plasmonic modes. By using a Temporal Coupled-Mode Theory based approach
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2019-03
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4. Piezoelectricity from Elastic and Dielectric Measurements on Unpoled Ferroelectrics
A method is described to assess the piezoelectric response of ferroelectric materials from the temperature dependence of the elastic moduli and dielectric constant of unpoled samples. The limits and advantages over the traditional methods on poled samples are discussed. A quantitative check is made by comparing the piezoelectric softening measured below the
Mat. Res.. Publicado em: 07/06/2018
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5. Polarization Insensitive Compact Wide Stop-band Frequency Selective Surface
Abstract A compact, polarization insensitive, wide stop band frequency selective surface is presented. The unit cell is designed by modifying the basic square loop FSS. The simulated value of bandwidth for transmission < ‒ 20 dB for TE incident wave is 7.7 GHz from 4.71 GHz to 12.41 GHz which is 89.95% corresponding to the center frequency of this range. I
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2018-03
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6. Nonlinear Forced Vibration Analysis of Dielectric-Elastomer Based Micro-Beam with Considering Yeoh Hyper-Elastic Model
Abstract The present study investigates nonlinear forced vibration of dielectric elastomer-based micro-beam. The nonlinear terms in beam equation are geometric and material one. Geometric nonlinearity is considered by von-Karman strain displacement relationship and the material nonlinearity is modeled with Yeoh hyper-elastic model. Galerkin and Multiple scal
Lat. Am. j. solids struct.. Publicado em: 2017-03
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7. Measured Dielectric Permittivity of Contaminated Sandy Soil at Microwave Frequency
Abstract Measurement of dielectric permittivity of soil has been studied by many researchers. However, few studies have been conducted on contaminated soil. The motivation of the present study is to investigate the behavior of sandy soil contaminated by lubricant oil at microwave frequency. Two different artificially prepared soil samples are measured in the
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2016-06
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8. Impedance and Modulus Spectroscopy Characterization of Tb modified Bi0.8A0.1Pb0.1Fe0.9Ti0.1O3 Ceramics
In this paper we present the impedance spectroscopy of ternary solid solutions of BiFeO3, TbFeO3 and PbTiO3, prepared by solid-state reaction method. The preliminary structural studies were carried out by x-ray diffraction technique, showing the formation of polycrystalline sample with ABO3 type of perovskite structure with hexagonal symmetry for Bi0.8Tb0.1P
Mat. Res.. Publicado em: 16/02/2016
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9. Effect of magnetic ion doping on structural, electric and relaxor properties of Pb (Fe2/3W1/3) O3 multiferroic ceramics
Single-phase Pb(Fe2/3W1/3)O3 (PFW) multiferroic ceramics doped with magnetic ions were fabricated using a modified B-site precursor method. Dielectric response was investigated over a wide range of temperature and frequency. Doping did not modify the characteristic temperatures (T C, T N) and the order at ferroelectric phase transition, keeping the relaxor p
Mat. Res.. Publicado em: 2014-12
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10. Aplicação de novos materiais em transistores de efeito de campo ferroelétricos
In this work, we investigated the electrical properties of the polyelectrolyte PSS in its sodium form (PSS-Na, Polystyrene sulfonic in the sodium form) and acid form (PSS-H, polystyrene sulfonic in the acid form) and also doped with Fe3+ for application in Ferroelectric Field Effect Transistors (Fe-FET). The PSS-Na was acquired from Aldrich and PSS-H was obt
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/07/2012
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11. Influência da condutividade e permissividade do solo em função da frequência no cálculo da impedância longitudinal e admitância transversal de linhas aéreas de transmissão / Influence of earth´s conductivity and permittivity frequency dependence on longitudinal impedance and transversal admittance transmission line´s parameters calculation
This thesis aims to propose more accurate models for calculating the electrical parameters of overhead power transmission lines. The influence of earth s conductivity and permittivity frequency dependence is evaluated when calculating transversal and longitudinal transmission lines parameters in the frequency range 0 to 2 MHz. This frequency range covers the
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/04/2010
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12. MICROWAVE DEVICES USING HIGH DIELECTRIC CONSTANT FILMS / DISPOSITIVOS DE MICROONDAS UTILIZANDO FILMES DE ALTA CONSTANTE DIELÉTRICA
The growing demand for portable devices with more reduced size and weight has stimulated the search for materials with high dielectric constant and low losses in the microwave frequency range allowing circuit integration and miniaturization. In this work, a theoretical and experimental study of the use of high dielectric constant films in the fabrication of
Publicado em: 2010