Search

This study aimed to synthesize Bi2Fe4O9 and apply it to the degradation of tartrazine yellow dye. Bi2Fe4O9 was synthesized using the solid-state reaction and the Pechini method. The materials obtained were characterized using X-ray diffraction (XRD), visible ultraviolet spectroscopy (UV-Vis) and field emission scanning electron microscopy (FEG). The microscopic images revealed a morphological difference between the two materials in which the material obtained by the Pechini method is the most porous and have the largest surface area. The pellet obtained by the Pechini method was seen to have a lower bandgap value when compared with the sample solid state reaction. In the photocatalysis tests, the best performance was also that of the material obtained by the Pechini method, with 99.34% degradation, while the material obtained by solid state reaction showed 85.86% in 120 minutes. The solution degraded with the material obtained by the Pechini method presented 81.66% of mineralization while the solution with the material obtained by solid state reaction showed 60.97% of mineralization. The results confirmed that the material obtained by both syntheses is able to maintain its effectiveness after 10 repetitions of the photocatalytic process, proving to be promising for waste treatment in the industrial field. [ABSTRACT FROM AUTHOR]

Although it is generally accepted that the tribe Genisteae has rather homogeneous pollen, we have found considerable variation in pollen size and morphology in Cytisusand related genera (Argyrocytisusand Chamaecytisus), which match taxonomic groups defined on morphological grounds. The results of Principal Component Analysis of pollen characteristics show the following: CytisusSect. Alburnoidesis well-delimited, with the smallest pollen grains and the simplest pattern in the tectum, fossulate-perforate to perforate; No separation of C. villosus(Sect. Cytisus) from Sect. Alburnoidesis observed; CytisusSect. Spartopsis, with the largest pollen grains and reticulate to reticulate-fossulate ornamentation, forms an isolated group; C. fontanesii(Sect. Heterocytisus) stands apart from other Cytisusspecies by its homogeneous ornamentation and the perforate instead of psilate-punctate margo. Thus, the pollen data supports its transfer to the separated genus Chronanthos; Pollen ornamentation and morphology also support the separation of Argyrocytisus battandieriand Chamaecytisus mollisfrom Cytisus. [ABSTRACT FROM AUTHOR]