Wavelet-Based determination of Cu and Pb in water samples using potentiometric stripping analysis with a Lab-Made potentiostat

This paper demonstrates the possibility of simultaneously determining lead and copper in mineral, river and tap water by potentiometric stripping analysis using a low-cost lab-made potentiostat and a wavelet-based signal processing method. Pb(II) and Cu(II) concentrations were found to be in the range 3-7 µg L-1. Relative standard deviations were on average smaller than 3%, which is satisfactory in view of the trace concentration. For comparison, the determination was also carried out by using a high-end commercial equipment (μAutolab Type II, Eco Chemie). The average and standard deviation of the results were similar to those obtained with the lab-made potentiostat. No significant statistical difference was verified according to a paired t-test at a confidence level of 95%

Flow-batch analyzer for the chemiluminescence determination of catecholamines in pharmaceutical preparations

A novel, simple, cheap, flexible, versatile, and highly sensitivity flow-batch analyzer (FBA) with chemiluminescence detection was developed for determination of dopamine, norepinephrine, and epinephrine in pharmaceutical preparations. The method was based on the inhibitory effect of the mentioned catecholamines on a luminol-potassium hexacyanoferrate (III) chemiluminescence system in alkaline medium. The optimization of the chemical variables affecting this chemiluminescence inhibition effect has been carried out using a Box-Behnken experimental design. The sample throughput was 28 h-1. The system allowed the automatic preparation of standard solutions and analytical process can be accomplished just by changing the operational parameters in FBA control software.Fil: Grunhut, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Martins, Valdomiro L.. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Centurión, María Eugenia. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Araújo, Mário Cesar Ugulino de. Universidade Federal da Paraiba; BrasilFil: Fernández Band, Beatriz Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin

Protocolo de pesquisa sobre as emoções na idade idosa: uma revisão de escopo

Esta revisão de escopo visa mapear os principais conceitos encontrados no meio científico/acadêmico que apoiem o tratamento das emoções dos idosos e sua afetividade na sua qualidade de vida