Vinicius Oliveira

Synthesis and characterization of two new niobium(V) diperoxo complexes containing 8-quinolinolate as the ligand

Abstract Two new diperoxo complexes of niobium using 8-quinolinolate (Q) as the ligand, K[NbOH(O 2 ) 2 Q]·2H 2 O ( 1 ) and K[Nb(O 2 ) 2 Q 2 ]·3H 2 O ( 2 ), have been synthesised and characterised structurally by elemental analysis, IR and NMR ( 1 H, 13 C, 93 Nb) spectroscopy. The 1 H and 13 C NMR signals of the free ligand undergo shift on complexation.

Bioremediation of nitrogenous compounds from oilfield wastewater by Ulva lactuca (Chlorophyta)

ABSTRACT Oilfield wastewater (OFW) is a by-product of petroleum production and has a high nitrogen concentration. Bioremediation by macroalgae appears to be an option for OFW, and the genus Ulva (Chlorophyta) has strong potential as an agent of bioremediation because of its high nitrogen absorption capacity. This experimental study evaluated the efficiency of bioremediation of nitrogenous compounds in three concentrations of OFW by Ulva lactuca. One-phase decay models, photosynthetic status (assessed by pulse amplitude–modulated [PAM] fluorometry), and growth rate were used to assess bioremediation efficiency and algal physiology. All nitrogenous compounds were removed during the experimental period. The models that were applied for ammonium showed a stronger bioremediation effect for OFW at a concentration of 25% than at concentrations of 12.5% and 2.5%, and for nitrate, the models showed a stronger bioremediation effect at the 12.5% OFW concentration. The minor effects of OFW on photosynthetic performance and growth, added to high removal of nitrogen, emphasize the bioremediation capacity of U. lactuca, suggesting a new possibility of bioremediation of this waste.

Four new additions to the marine flora of Fernando de Noronha Archipelago, Tropical western South Atlantic Ocean

The macroalgae of the archipelago were first studied in the nineteenth century (Dickie 1874; Hemsley 1885; Murray 1891), and since then, occasional surveys have increased the knowledge of the diversity of the local species of benthic seaweed. Currently, the marine flora of Fernando de Noronha includes 135 taxa, represented by 56 species of Chlorophyta, 51 Rhodophyta and 28 Ochrophyta (Oliveira and Ugadim 1974; Eston et al. 1986; Szèchy et al. 1989; Pedrini et al. 1992).