Valores e Desenvolvimento Humano

A primeira parte desse Relatório de Desenvolvimento Humano do Brasil 2009/2010 começa com a descrição de um amplo processo de consulta aberta à sociedade, denominada Brasil Ponto a Ponto, para a escolha do tema do relatório. A Campanha Brasil Ponto a Ponto teve por objetivo estimular o debate em todo o país sobre o que precisa ser mudado no Brasil para melhorar a vida das pessoas. A campanha foi aberta a todos os brasileiros, que poderiam participar respondendo à pergunta: O que precisa mudar no Brasil para a sua vida melhorar de verdade

Effect of different electrolytes on the swelling properties of calyx[4]pyrrole-containing polyacrylamide membranes

Calix[4]pyrrole (1) was synthesized and characterized and this macrocycle was incorporated in polyacrylamide gels. The presence of meso-octamethyl-porphyrinogen inside of gel was checked using infrared spectroscopy, differential scanning calorimetry, and swelling studies. The swelling degree of these hydrogels in equilibrium with different electrolytes (NaCl, LiCl, KCl, CaCl2 and AlCl3) was measured in a concentration range 0.1-0.5 mol dm-3. Although no significant alterations in the swelling degree can be found for the different 1:1 electrolytes, when the cation charge of unsymmetrical electrolytes increases, the gel swells in a significant way. This swelling process is enhanced by the presence of calyx[4]pyrrole. The effect of alkaline hydrolysis of polaycrylamide-based hydrogels was also studied. The hydrolysed hydrogels collapse in the presence of the electrolytes; this behavior is dependent on the hydrolysis degree, electrolyte charge and calyx[4]pyrrole presence and concentration; the latter leads to polyacrylamide with tailor-made properties.http://www.sciencedirect.com/science/article/B6TWW-4K0FJT9-2/1/a2e10fed9f08e8248532610bc3e2bdc