The effect of two different anionic membranes on manganese deposition was studied in a two-compartment electrochemical reactor with a titanium cathode and a dimensionally stable RuO|Ti anode. Chronopotentiometry, ICP-OES, SEM, XRD and elemental mapping were used to understand the changes in concentration and characteristics of the metallic deposition at different current densities with the anionic membranes AMI 7001s and Neosepta AMX. The results demonstrate that AMI reduces more manganese than AMX below -100 A m, generating more metallic deposition but also more low-solubility manganous by-products, whereas both membranes exhibited similar behaviours above -100 A m reaching the maximum current efficiency (63%) at -200 A m.
View Article and Find Full Text PDFElectrochemical reduction of ionic species during manganese deposition from sulphated aqueous solutions has been studied in an electrochemical reactor with two anionic exchange membranes. Thermodynamic analysis, voltammetries, and chronopotentiometries were used to determine the reaction mechanism of the reductions developed, with the results demonstrating that the effect of the elemental selenium on the hydrogen evolution leads to the formation of elemental sulphur by reducing the sulphate ions with both membranes. It was also evident that in the range of -25 to -50 A m the electrodeposition of metallic manganese begins, with minimal interference from parasitic reactions.
View Article and Find Full Text PDFIn this work a Metal-Organic Framework (MOF) was prepared using a solvothermal method, taking as precursors 1. 2-di-(4-pyridyl)-ethylene, 1.2.
View Article and Find Full Text PDFObjective: Malaria parasites invade, grow and multiply inside erythrocytes and obtain nourishment from haemoglobin. Then, the released haem group is oxidized to haematin and inert dimeric haemozoin bio-crystals form, which provides the parasite a unique way to avoid the toxicity associated with the haem group. Therefore, antimalarial drugs are designed to inhibit dimer formation; however, recent electrochemical studies indicate that an inert dimer also promotes a toxic oxidizing environment.
View Article and Find Full Text PDFBackground: Understanding the significance of hemozoin (Hz) in the process through which is released from the heme group in the food vacuole during hemoglobin degradation, will allow the development of more effective drugs against malaria. Therefore, the development of methodologies to obtain Hz synthetically will facilitate an in vitro evaluation of new anti-malarial drugs.
Methods: We present a methodology with good results to obtain Hz from fecal material of blood-sucking insects .