Electrical Impedance
Mostrando 13-24 de 147 artigos, teses e dissertações.
-
13. Production of Nanometric Bi4Ti3O 12 Powders: from Synthesis to Optical and Dielectric Properties
This paper aims to evaluate the synthesis and annealing parameters for production of nanometric Bi4Ti3O12 and its properties. The powders were obtained through the solution combustion route and the impacts of annealing temperature on the materials’ physicochemical features as well as their optical and electrical properties were investigated. Thus, the prep
Mat. Res.. Publicado em: 16/07/2018
-
14. Preliminary results of cervical impedance measurements
AbstractIntroduction: In this work, we report the development and initial tests of a measuring system that is used to measure the cervical electrical impedance with the purpose of assessing cervical ripening. The objective is to offer a system that provides real-time information about the cervical electrical impedance and, indirectly, of the cervical ripeni
Res. Biomed. Eng.. Publicado em: 17/05/2018
-
15. Structural, optical and electrical properties of Ni-doped Co3O4 prepared via Sol-Gel technique
In this article, Nickel doped Cobalt oxide thin films and powders have been prepared on glass substrates using sol gel based dip coating process in order to investigate their optical, structural and electrical properties. The Ni concentration was changed from 0 to 9 wt(%).The synthesized samples were characterised by Ultraviolete visible analysis, X-ray diff
Mat. Res.. Publicado em: 07/02/2018
-
16. Thermal and Conductivity Studies of VO2+ Doped Methacrylic Acid - Ethyl Acrylate (MAA:EA) Copolymer Films
New polymer electrolyte films of Methacrylic Acid - Ethyl Acrylate (MAA:EA) copolymer embedded with different concentrations of VO2+ ions were prepared by solution casting technique. Thermal properties of these films were investigated employing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Electrical conductivity of the films
Mat. Res.. Publicado em: 23/10/2017
-
17. Electrical and thermal properties of PLA/CNT composite films
ABSTRACT Conducting polymers presents many potential applications such as biosensors and biofuelcells. However, to be used in those devices, a thin film must be deposited onto a conducting and biocompatible substrate. In this work, carbon nanotubes (CNT) were mixed in a poly (lactic acid) - PLA - matrix with different compositions (from 0.25 to 5.0 %) in ord
Matéria (Rio J.). Publicado em: 10/08/2017
-
18. Influence of additives on phase stabilization of scandia-doped zirconia
ABSTRACT The effects of small additions of tin, zinc, calcium and boron oxides on phase composition and electrical conductivity of zirconia-10 mol% scandia were investigated. Compounds containing 1 mol% zinc, tin and calcium oxides and 1, 3 and 5 wt.% boron oxide were prepared by solid state reaction and characterized by X-ray diffraction, density measuremen
Matéria (Rio J.). Publicado em: 01/06/2017
-
19. Power amplifier circuits for functional electrical stimulation systems
Abstract Introduction: Functional electrical stimulation (FES) is a technique that has been successfully employed in rehabilitation treatment to mitigate problems after spinal cord injury (SCI). One of the most relevant modules in a typical FES system is the power or output amplifier stage, which is responsible for the application of voltage or current puls
Res. Biomed. Eng.. Publicado em: 2017-06
-
20. Electrical and microstructural characterization of Gd-doped Ceria/Y-doped Zirconia bi-layer electrolyte prepared by tape casting
ABSTRACT GDC-YSZ bi-layer SOFC electrolytes are an interesting manner to protect GDC electrolytes of the low oxygen partial pressure present at anode-electrolyte interface. This oxygen partial pressure condition and high temperatures during the operation of SOFC permit GDC electrolyte reduction injuring the performance of SOFC. In this work, GDC-YSZ bi-layer
Matéria (Rio J.). Publicado em: 22/05/2017
-
21. Study of the Nanostructure Effect on Polyalkylthiophene Derivatives Films Using Impedance Spectroscopy
In this paper, devices fabricated with a diode-like structure (electrode/polymer/electrode) from spin-coated and nanostructured (Langmuir-Schaefer) films of polythiophene derivatives were characterized by impedance spectroscopy and studied by theoretical fitting to reach a better understanding of the physical processes in the devices. The materials used for
Mat. Res.. Publicado em: 20/03/2017
-
22. A low-profile and ultra-wideband printed antenna with a 176% bandwidth
Abstract This work reports the development of a simple, low-profile and ultra-wideband printed antenna. The proposed antenna is based on a truncated ground plane and an impedance matching structure formed by a round junction and two chamfers; these modifications significantly increase the antenna frequency bandwidth compared to conventional microstrip antenn
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-03
-
23. Electrical Conductivity in the KDP, ADP, and K1-x(NH4)xH2PO4 Crystals
Impedance Spectroscopy was performed to examine the electrical conductivity on KH2PO4 KDP, (NH4)H2PO4 ADP and K1-x(NH4)xH2PO4 (x = 0.076, 0.118, 0.357, 0.857, 0.942) crystals with increasing temperature. They were grown by solvent evaporation method. Zview simulation software was used to theoretically fit electrical conductivity results as a function of freq
Mat. Res.. Publicado em: 23/02/2017
-
24. Modificación de las propiedades estructurales, eléctricas y magnéticas del BiFeO3 por la incorporación de Ba y Nb
Bismuth ferrite (BFO) and Ba-Nb-substituted BFO with compositions Bi1-xBaxFeO3 (x= 0, 0.10, 0.15 y 0.20), BiFe1-yNbyO3 (y= 0, 0.03, 0.06 y 0.09) y Bi1-xBaxFe1-yNbyO3 (x= 0.10 (y= 0, 0.03, 0.06 y 0.09) powders were synthesized using the citrate-gel method. Infrared spectroscopy indicated shifting of Bi/Ba-O and Fe/Nb-O bond vibrations and a structural transit
Quím. Nova. Publicado em: 2017-02