Photothermal Spectroscopy
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. Photoacoustic Thermal Characterization of Banana Fibers
Natural fibers are attracting the interest of engineering sectors owing to specific advantages such as lightweight and lower cost as well as an inherent condition of being renewable, biodegradable, recyclable and environmentally correct with respect to CO2 emission. In addition, several natural fibers present mechanical and thermal properties appropriate for
Mat. Res.. Publicado em: 2015-12
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2. Determinação das propriedades térmicas e óticas do semicondutor CdTe por espectroscopia fototérmica / Determination of thermal and optical properties of the semiconductor CdTe by photothermal spectroscopy
Este trabalho faz uma sucinta revisão de literatura em que são abordadas as técnicas de espectroscopia fotoacústica (PAS) e fotopiroelétrica (PPES). Para utilização destas técnicas espectroscópicas, são necessárias células de detecção de sinal fotoacústico e fotopiroelétrico, que foram desenvolvidas e testadas. Após o desenvolvimento da inst
Publicado em: 2008
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3. Photothermal characterization of low density polyethylene food packages
The present work discuss the applicability of photothermal techniques for determining diffusion coefficients of oxygen and carbon dioxide of commercial low-density polyethylene (LDPE). The methodology involves the monitoring of diffused gas by a photoacoustic analyzer. Diffusion coefficients measured for CO2 and O2 were 2.77 x 10-8 cm²/s and 1.68 x 10-7 cm�
Polímeros. Publicado em: 2004-03
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4. Estudos espectroscopicos e caracterização termica de materiais por tecnicas fototermicas
O estudo de propriedades térmicas e espectroscópicas de materiais tem despertado o interesse não só no meio acadêmico, mas também entre diversos setores industriais. Muitas são as técnicas que possibilitam este tipo de pesquisa, porém as técnicas fototérmicas têm demonstrado extrema eficiência para uma diversidade enorme de estudos e materiais.
Publicado em: 2004
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5. Dopagem tipo-n e mudanças estruturais induzidas pelo nitrogenio de filmes de germanio amorfo hidrogenado
In this work several informations are presented and discussed about structura1 and optoelectronic properties of doped samples of hydrogenated amorphous germanium (a-Ge:H) using P, As (solid sources) and N (using NH3) as doping impurities. In addition, we studied structura1 changes of a-Ge:H induced by N, in the nitrogen concentration range of ~2-6 at. %. The
Publicado em: 1998
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6. Bismuth doping of hydrogenated amorphous germanium
t: The addition of small quantities of bismuth to hydrogenated amorphous germanium (a-Ge:H), changed its electrical conductivity and bandgap. Detailed data were obtained from measurements of electrical conductivity, optical and infrared transrnission, and from photothermal deflection spectroscopy. Films of a-Ge:H having Bi atomic concentrations ranging betwe
Publicado em: 1998
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7. Propriedades estruturais da liga de a-Si-x Cx:H
In this present work, we mainly study the tendency of formation of homonuclear and heteronuclear bonds (chemical order) in a-Si1-xCx:H deposited by RF co-sputtering, and its correlation with optical properties, such as gap energy and structural disorder. The reason on using this deposition technique is that it permits the control of the hydrogen content whil
Publicado em: 1996
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8. Ligas amorfas de silicio e germanio hidrogenadas e materiais relacionados
Neste trabalho estudamos as ligas amorfas de silício e germânio hidrogenadas (a-SixGe1-x:H), o germânio amorfo hidrogenado (a-Ge:H), além do silício amorfo hidrogenado (a-Si:H). Apresentamos resultados nas propriedades estruturais e opto-eletrônicas de ligas crescidas por r.f. sputtering, ricas em germânio (x £ 0.25). Encontramos que para x £ 0.1 a
Publicado em: 1994
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9. Combinatorial discovery of oxidative dehydrogenation catalysts within the Mo-V-Nb-O system
Combinatorial methodologies were used for the synthesis and screening of mixed metal oxide heterogeneous catalysts. Primary screening at low reactant conversions at a throughput of greater than 10,000 catalyst compositions per month was performed by using simultaneous MS and photothermal deflection spectroscopy on spatially separated thick film catalysts wit
The National Academy of Sciences.