| dc.contributor | Cruz Mandujano, J., Universidad Michoacana de San Nicolás de Hidalgo, Dpto. de Ciencias Básicas Y Matemáticas, Facultad de Ingeniería Civil, Mexico; Egberto Bedolla, B., Instituto de Investigaciones Metalérgicas, Universidad Michoacana de San Nicolás de Hidalgo, Mexico; Villafaña Rauda, E., Centro Universitario de Los Lagos, Universidad de Guadalajara, Mexico | |
| dc.description.abstract | Using the open photoacoustic cell technique, we obtained the spectra of the photoacoustic signal amplitude as a function of the modulation frequency of the incident radiation. From these spectra we determined the thermal diffusivity in Mg- AZ91E/AlN metal matrix composite with a magnesium alloy of around 9% aluminum and 1% zinc, the aluminum nitrade (AlN) is a ceramic with relationship AlN/AZ91E with ratio 1:1. The photoacoustic signal amplitude in the region thermally thick and optically opaque is used to calculate the thermal diffusivity of the Mg-AZ91E/AlN material and the results obtained are shown. " 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).",,,,,,"10.1117/12.903426",,,"http://hdl.handle.net/20.500.12104/44824","http://www.scopus.com/inward/record.url?eid=2-s2.0-84858401172&partnerID=40&md5=8a5ca18622f7f428713936ef2488ebef",,,,,,,,"Proceedings of SPIE - The International Society for Optical Engineering",,,,"8011",,"Scopus",,,,,,"composite; diffusivity; Photoacoustic",,,,,,"Study of thermal properties of metallic samples AZ91E/ALN",,"Conference Paper"
"46611","123456789/35008",,"Tafoya, D., Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden, Centro de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72, 58089 Morelia, Michoacán, Mexico; Franco-Hernández, R., Instituto de Astronomía y Meteorología, Universidad de Guadalajara, Avenida Vallarta No. 2602, 44130 Guadalajara, Jalisco, Mexico, Departamento de Astronomía, Universidad de Chile, Casilla 36-D Santiago, Chile; Vlemmings, W.H.T., Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden; Pérez-Sánchez, A.F., Argelander Institute for Astronomy, University of Bonn, Auf dem Hügel 71, 53121 Bonn, Germany; Garay, G., Departamento de Astronomía, Universidad de Chile, Casilla 36-D Santiago, Chile",,"Tafoya, D. | |
| dc.description.abstract | Garay, G.",,"2014",,"We report the first detection of submillimeter water maser emission toward water-fountain nebulae, which are post-AGB stars that exhibit high-velocity water masers. Using APEX we found emission in the ortho-H2O (10 29 ? 936) transition at 321.226 GHz toward three sources: IRAS 15445-5449, IRAS 18043-2116, and IRAS 18286-0959. Similar to the 22 GHz masers, the submillimeter water masers are expanding with higher velocity than do OH masers, suggesting that these masers also originate in fast bipolar outflows. In IRAS 18043-2116 and IRAS 18286-0959, which figure among the sources with the fastest water masers, the velocity range of the 321 GHz masers coincides with the range of the 22 GHz masers, indicating that they probably coexist. Toward IRAS 15445-5449, the submillimeter masers appear in a different velocity range, indicating that they trace different regions. The intensity of the submillimeter masers is comparable to the 22 GHz masers, implying that the kinetic temperature of the region where the masers originate should be T k > 1000 K. We propose that the passage of two shocks through the same gas can create the conditions for explaining the strong high-velocity 321 GHz masers coexisting with the 22 GHz masers in the same region. " 2014 ESO. | |
