RESUMEN
An experimental system has been set up to investigate the reaction kinetics of framboidal pyrite oxidation in real, reactive acid sulfate soil assemblages. This study was undertaken to determine the degree to which pyrite oxidation rates are reduced by bacteriological reactions and organic matter, which both modify the net reaction mechanisms and compete for available oxygen. The results from these experimental runs not only confirm the role of organic matter in mitigating pyrite oxidation but indicate that at least initially, the acidity produced is consumed or otherwise ameliorated by parallel reactions. Tracking pH or [H+] in both a reactor and in soil does not accurately reflect reaction progress and may not correctly indicate the true level of risk. In comparison, the tracking of pyrite oxidation with the concentration of sulfate in solution is not affected by side reactions or precipitation and is therefore a better indicator for the rate of pyrite destruction.
Asunto(s)
Hierro/química , Microbiología del Suelo , Suelo/análisis , Sulfuros/química , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Queensland , Sulfatos/químicaRESUMEN
A multicenter randomized clinical trial can offer exciting and challenging opportunities to the clinical coordinators and other health professionals who participate in the conduct of a clinical trial at the clinical units. This article will address an acute intervention trial, the Multicenter Investigation of the Limitation of Infarct Size, and demonstrate some of the important responsibilities of the clinical unit research nurse coordinators in the conduct and operation of this trial.