988 resultados para Química Inorgánica


Relevância:

70.00% 70.00%

Publicador:

Resumo:

This study aimed to determine the concentration and inorganic chemical composition of samples from airborne particulate matter inhaled in fine and coarse fractions. Aerosol samples were collected in 2013 and 2014, from sites located in the cities of Londrina and Maringa, in the state of Paraná, Brazil. The samples were collected daily (24h) in two campaigns: winter and summer. For the collection, was used a dichotomous sampler with quartz fiber filter with 47 mm in size and 2 µm porosity, 97% efficiency, retaining particles of up to 0.3 µm. Quantification of the airborne particulate matter mass was performed by gravimetry method. The results from Londrina to PM2.5 and MP2,5-10 represent, respectively, 29.2% and 70.8% of airborne particulate matter in the winter campaign (2013), 30.9% (PM2.5) and 69.1 % (MP2,5-10) in the summer campaign (2013), and 35.9% (PM2.5) and 64.1% (MP2,5-10) in the winter 2014 campaign. In the city of Maringa, the results presented the percentage of 42.0% (PM2.5) and 58.0% (MP2,5-10) for the winter season (2014), and 28.8% (PM2.5) and 71.2 % (MP2,5-10) for the summer season (2014). The PM2.5/PM10 ratio was on average 0.3, demonstrating that both cities are developing urban areas. Analysis of the major soluble inorganic species in water (NO3-, SO42- and Cl-) associated with MP2,5-10 were quantified by ion chromatography at the LACA Laboratory in the State University of Londrina, with the largest contribution found in all campaigns was to NO3-. The NO3-/SO42- ratios above 1.0 indicate the local traffic contribution. The analysis of metals associated with PM2.5 was carried out by mass spectrometry with inductively coupled plasma (ICP-MS) in the Federal University of Santa Catarina. The Zn, Pb, Cu and Mn concentrations found in all campaigns indicate the contribution of mobile sources to PM2.5. The concentration of BCe in PM2.5 was determined by reflectance, with higher BCe concentrations being found in winter campaigns. In general, Londrina presented the highest concentrations from the species analyzed when compared to Maringá. In addition, the analysis of the air mass trajectories indicated the transportation of pollutants coming mainly from fires in the southeastern region of the country.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

La asignatura de “Química del Estado Sólido” se imparte actualmente en los Másteres de “Ciencia de Materiales” e “Interuniversitario de Nanociencia y Nanotecnología Molecular”. El programa de esta asignatura en ambos Másteres es ligeramente distinto, ya que en principio así se pensó atendiendo a las particularidades de los objetivos de aprendizaje en cada Máster. Después de la experiencia adquirida tras unos años de funcionamiento de esta asignatura, y dado que la asignatura tiene en ambos Másteres el carácter de “básica”, los autores creen que es posible proceder a una homogeneización curricular con el fin del aprovechamiento de recursos (no sólo humanos, sino también de espacio y tiempo). Esto permite que la asignatura pudiese ser impartida con los mismos objetivos de enseñanza-aprendizaje en ambos Másteres y de manera simultánea. En este trabajos e aborda una propuesta de metodología docente según un enfoque didáctico que cubre las necesidades de formación en ambos Másteres.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

254 p : il, graf. col.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Con este proyecto se pretende encontrar una ruta de procesado para obtener materiales semejantes a los aerogeles. El procedimiento se basa en la sublimación a temperatura ambiente de un sólido adsorbido en el interior de un gel de sílice.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

32 p.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Tese de doutoramento, Química (Química Inorgânica), Universidade de Lisboa, Faculdade de Ciências, 2014

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Tese de doutoramento, Química (Química Inorgânica), Universidade de Lisboa, Faculdade de Ciências, 2015

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Tese de doutoramento, Química (Química Inorgânica), Universidade de Lisboa, Faculdade de Ciências, 2015

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Tesis (Maestría en Ciencias con Especialidad en Química Inorgánica) UANL

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Tesis (Doctor en Ciencias con Orientación en Química Inorgánica) UANL, 2010