Optical Fibers
Mostrando 13-24 de 194 artigos, teses e dissertações.
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13. Effect of Alkaline and Hot Water Treatments on the Structure and Morphology of Piassava Fibers
The effect of alcaline and hot water surface treatments of piassava Attalea funifera fibers was investigated. The efficiency of each treatment was evaluated by Fourier transform infrared spectroscopy, X-ray diffractometry, optical microscopy, scanning electron microscopy and atomic force microscopy. The alkaline treatments were effective in removing the supe
Mat. Res.. Publicado em: 01/02/2018
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14. Analysis of Parameters for a Distributed Temperature Sensing based on Raman Scattering
Abstract This paper presents a theoretical and computational study on the analysis of parameters for distributed temperature sensing in optical fibers, based on spontaneous Raman scattering effect. The parameters studied were the optical power level, the range of frequency modulation and the length of the sensor element, as well as the application of optical
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-03
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15. Morpho-anatomy of the leaf of Myrciaria glomerata
Abstract Myrciaria glomerata O. Berg., Myrtaceae, popularly known as "cabeludinha", has high content of ascorbic acid and anti-inflammatory property and is used in folk medicine. The objectives of this study were the morphological, anatomical and histochemical characterization of the leaves. Leaf studies were made with optical, scanning electron and confocal
Rev. bras. farmacogn.. Publicado em: 2016-06
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16. MATERIAIS VÍTREOS E LUZ: PARTE 2
In this second part it will be discussed some photonic applications of glassy and glass ceramic thin films which can be used as planar waveguides. Some photonic applications require certain specifications of glass, which can be quantified by studying the nonlinear optical properties of the materials. Therefore, a brief introduction of these phenomena is disc
Quím. Nova. Publicado em: 2016-04
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17. A Multilayer Approach for Optical Network Planning
With the increase in demand to Backbone networks, one became fundamental the application of new telecommunication technologies for efficient use of devices and optical links, such as xPSK modulations with dual polarization, dispersion compensating fibers, coherent detection and digital processing signals. Thus, network planning using analytical models have b
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2016-03
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18. Chromatic Dispersion of an Optical Fiber Based on Photonic Quasicrystals with Twelve-Fold Symmetry and its Application as Directional Coupling
Abstract Optical fibers composed by photonic quasicrystals it is based on aperiodic structures characterized by at least two different symmetrical patterns from the base matrix. In this work, an optical fiber composed by quasi-periodic and symmetric matrix was analyzed using the finite element method in conjunction with cylindrical perfectly matched layers.
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2015-12
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19. Evolution of texture and microstructure during thermo-mechanical processingin ultrathin low carbon steels
ABSTRACT In this research paper an analysis concerning the evolution of crystallographic texture during hot rolling processing of low carbon steel is presented. The study was performed on a steel sheet with an initial thickness of 1.9 mm used in the process of cold rolling. In order to assess the differences between tensile and compressive deformation, a 90�
Matéria (Rio J.). Publicado em: 2015-09
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20. Dimensions and refractive index estimates of deeply buried optical waveguides in Lithium Fluoride
A recursive procedure is applied to the measured near-field profiles of buried optical waveguides recorded in a lithium fluoride (LiF) crystal by femtosecond laser pulses in order to estimate the core dimensions and the refractive index increase. Albeit the waveguides transversal section geometry is quite complex it is possible to obtain the horizontal and v
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2014-06
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21. Spectrally-efficient 17.6-Tb/s DWDM optical transmission system over 678 km with pre-filtering analysis
We present and analyze a 17.6-Tb/s DWDM optical transmission composed of 79 channels with 224-Gb/s RZ-DP-16QAM modulation format per-channel and coherent detection. A maximum reach of 678 km is obtained with an optical recirculation loop composed by 226 km of pure-silica core fibers and EDFA amplification only in a 50-GHz grid system with spectral efficiency
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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22. Theoretical and experimental comparison between power and degree of polarization based optical fiber current sensors
This paper presents a theoretical and experimental comparison of two techniques of optical fiber current sensors (OFCS) based on the Faraday Effect: the power and the degree of polarization (DOP) methods. The DOP method is shown to be insensitive to state of polarization (SOP) changes induced by environmental conditions. A maximum variation of 0.4% in the DO
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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23. Long-term stability decay of standard and regenerated Bragg gratings tailored for high temperature operation
Thermal stability of both standard and regenerated Bragg gratings written in normal and photosensitive optical fibers was accessed. An apparent spectral wavelength stabilization of common gratings with no thermal hysteresis was reached after thermal treatments. However, after a time interval of 5 months, gratings exhibited a shift in the resonance Bragg wave
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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24. Spectrally-efficient 17.6-Tb/s DWDM optical transmission system over 678 km with pre-filtering analysis
We present and analyze a 17.6-Tb/s DWDM optical transmission composed of 79 channels with 224-Gb/s RZ-DP-16QAM modulation format per-channel and coherent detection. A maximum reach of 678 km is obtained with an optical recirculation loop composed by 226 km of pure-silica core fibers and EDFA amplification only in a 50-GHz grid system with spectral efficiency
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-06