Análisis preliminar de la fitotoxicidad del material particulado sedimentable de la zona urbana de Cuenca

Este artículo informa sobre la valoración de la fitotóxicidad del Material Particulado Sedimentable (MPS) en la zona urbana del cantón Cuenca. El MPS se recolectó en tres sitios de la zona urbana, mediante el método descrito en el Texto Unificado de Legislación Ambiental Secundaria del Ministerio del Ambiente (TULASMA). Por el material particulado se realizó la determinación de la concentración de los componentes utilizando el análisis gravimétrico, la de los metales pesados por espectroscopía de absorción atómica, y la de aniones por método adaptado de referencia EPA 300.1. Posteriormente se evaluó su fitotóxicidad en cuatro especies, mediante el bioensayo de germinación y elongación de raíz e hipocótilo, en semillas de Lactuca sativa, Brassica oleracea itálica, Allium cepa y Raphanus sativus. En el bioensayo las semillas se expusieron a diferentes diluciones de la suspensión acuosa de MPS. Los resultados muestran que el efecto de los MPS dependió de la concentración y de la especie analizada, evidenciando diferentes grados de fitotóxicidad.

Estudo das propriedades biocompatíveis de arcabouços poliméricos derivados de óleos vegetais para aplicação na engenharia de tecidos

Dissertação (Mestrado em Tecnologia Nuclear)

Desenvolvimento de eletrocatalisadores de PdM (M= Ni, Cu, Ag) para reação de redução de oxigênio em meio básico na ausência e presença de álcool

Tese (Doutorado em Tecnologia Nuclear)

Formulação e caracterização de matérias-primas para revestimento cerâmico Semi-Poroso com adição de chamote de telhas

The ceramics industry in Piauí is nowadays with 55 industries where 11 are in Teresina which is the mainstream of the state, producing 55 million shingles; in which 10 % is of this production is wasted being sometimes thrown on the margins of rivers, roads and highways provoking an environmental degradation. The main goal of this work is to verify the potential of producing semi porous ceramic using grog of shingles, on the first part of this work bodies-of-proof were produced from a basic formula of an industry, doping it with 5 %, 10 %, 15 % and 20 % in mass and in the second part of this work some bodies-of-proof were produced from a formula where one raw material was substituted by 50 % of grog and another substituting it all by grog, bodies-of-proof made of a basic formula previously announced was used for experiment control.The grog and the raw materials were characterized by: particle size analysis , thermal differential analysis, X ray diffraction , X ray fluorescence, an thermal gravimetric analysis and rational analyses. The bodies-of-proof were sintetisized in an industrial oven obeying the normal cycle adopted by an industry, with peak temperatures of 1135 oC and a fast burning cycle of 25 minutes having as energetic fuel liquefied petroleum gas . The pieces that were obtained by this were submersed in rehearsed physics of: water absorption of, apparent specific mass, apparent porosity, lineal retraction, rupture tension to the flexural and dilatometry; mineralogical analysis for X ray diffraction; and microstructural for electronic microscope of sweeping. For all the formulas with addition of grog, superior priorities to the requested by the requirements for semi porous and for the formula to F2-2,5 superior priorities to standard formulas which justifies the incorporation of the shingles in mass for the semi porous ceramic