Infrared Detectors
Mostrando 1-12 de 18 artigos, teses e dissertações.
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1. Propriedades ópticas, magnéticas e estruturais de monocristais Cs2NaAlF6 dopados com cromo trivalente / Optical, magnetic and structural properties of Cs2NaAlF6 single crystals doped with trivalent chromium
This work is devoted to study the optical, magnetic and structural properties of the elpasolite crystal Cs2NaAlF6 with 0.1, 1.0, 3.0, 10.0, 30.0 and 50.0% of Cr3+ ions. The interest on this material lies on the fact that such system presents a broad, intense band in the visible and infrared regions at room temperature and therefore can be used as a tunable r
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/08/2011
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2. Uncooled detectors of continuum terahertz radiation
THz continuum spectral photometry has new and unique applications in different civil and military areas presenting a number of distinctive advantages on the well known microwaves or mid- to near-infrared technologies. THz sensing is essential to investigate the emission mechanisms by high energy particle acceleration processes. Technical challenges appear to
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2011-06
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3. Métodos para avaliação das emissões de gases do efeito estufa no sistema solo-atmosfera / Methods for the assessment of greenhouse gases emissions in the soil-atmosphere system
A escolha do método para avaliar as emissões de gases do efeito estufa (GEE) é uma etapa importante para o conhecimento e/ou desenvolvimento de práticas agrícolas com potencial de mitigação do aquecimento global. A presente revisão tem por objetivo apresentar vantagens e limitações de métodos utilizados para quantificação dos fluxos de dióxido
Publicado em: 2010
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4. Modelo da galáxia utilizando contagens de estrelas no infravermelho / Galaxy model by using infrared star counts
The majority of first quantitative models for the structure of Galaxy used the star counts method to explore the most important galactic structure parameters as a whole. Some of the most important models owe to Bahcall \& Soneira (1980), the Besançon group (Robin \& Crezé (1986)), Wainscoat et al. (1992), Ortiz \& Lépine (1993), among others.
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 29/02/2008
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5. Quantum dots: photodetectors, weak localization and counter-rotating edge states / Pontos-quânticos: fotodetectores, localização-fraca e estados de borda contra-rotativos
In this work we present transport properties of heterostructures with quantum-dots. Three subjects were exploited: on the first one, we observed anomalous quantum Hall plateaus, for wich we attributed to the existence of counter-rotating edge-states; on the second subject, we determined the decoherence time of the bidimensional electron system as a function
Publicado em: 2008
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6. Lead telluride p-n junctions for infrared detection: electrical and optical characteristics
PbTe mesa diodes were fabricated from a series of p - n junctions grown on BaF2 substrates. For this series, the hole concentration was kept constant at 10(17) cm-3 and the electron concentration varied between 10(17) and 10(19) cm-3. Capacitance versus voltage analysis revealed that for n > 10(18) cm-3, a one-sided abrupt junction is formed. The direct and
Brazilian Journal of Physics. Publicado em: 2006-06
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7. Semiconductor characteristics of Nd doped PbO-Bi2O3-Ga2O3 films
In this work optical and semiconductor characteristics of gallium oxide based thin films are studied. This material has important electro-optic applications and offers possibilities for semiconductor applications in heavy metal oxide semiconductor technology. In this study thin films of PbO-Bi2O3-Ga2O3 were deposited by reactive sputtering. Two targets with
Brazilian Journal of Physics. Publicado em: 2006-06
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8. Evaluation of EOS/MODIS and NOAA/AVHRR sensors in the detection and reporting of fires and burnings / Avaliação dos sensores EOS/MODIS e NOAA/AVHRR na detecção e registro de incêndios e queimadas
The efficiency of detection and monitoring of fire forests is fundamental for fire control and reduction of costs and damages in firefighting operations. Therefore the need for efficient methods for forest fire detection, allowing a faster action and better decision-making. Remote sensing can be a suitable tool for preventing and fighting forest fires. The o
Publicado em: 2006
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9. Electrical characterization of PbTe p-n junctions for applicarion in infrared detectors. / Caracterização elétrica de junções p-n de PbTe para aplicação em detectores de infravermelho.
This work reports on the electrical characterization of PbTe p-n junctions for application in photovoltaic detectors in the medium infrared range. For this purpose, a series of p-n junctions, where the hole concentration p was kept at 1017 cm-3 and the electron concentration n varied between 1017 and 1019 cm-3, was successfully grown by molecular beam epitax
Publicado em: 2004
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10. ACCURACY OF HIGH TEMPERATURE MEASUREMENT IN INDUSTRIAL PROCESSES / CONFIABILIDADE METROLÓGICA DA MEDIÇÃO DE ELEVADAS TEMPERATURAS EM PROCESSOS INDUSTRIAIS
The accuracy of high temperature measurement in industrial processes is important for safety reasons and product quality and specification in different industries. Due to the fact that the traceability of temperature measurement by infrared thermometers, as used in industrial processes, is only assured by Inmetro (National Institute for Metrology, Standards
Publicado em: 2004
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11. Caracterização elétrica de junções p-n de PbTe para aplicação em detectores de infravermelho. / Electrical characterization of PbTe p-n junctions for applicarion in infrared detectors.
Este trabalho visa à caracterização elétrica de junções p-n de PbTe para aplicação em detectores fotovoltaicos na faixa do infravermelho médio. Para isto, uma série de junções p-n foi crescida com sucesso por epitaxia de feixe molecular sobre substratos de fluoreto de bário. Nesta série, a concentração de buracos p ficou mantida fixa em 1017
Publicado em: 2004
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12. Desenvolvimento e aplicação de modelos de transferencia de calibração em espectroscopia no infravermelho proximo de ondas curtas (SW-NIR)
The aim of this work was the development of calibration models using short wave near infrared and the application of calibration transfer techniques in analytical chemistry. In this studies were used three kinds of samples: cachaça, syrup s soft drinks and gasoline. In the first application, have been developed a calibration model to quantifying, in the tem
Publicado em: 2003