Abstract The effect of microwave heating on the expansion of vermiculite was studied at a level of 700 W for 4 min exposure time and compared with raw vermiculite. In this study, the characterization of vermiculite from a mine in the northeast region of Brazil was performed using thermogravimetry, N2-adsorption, cation exchange capacity, X-ray powder diffraction (XRD), infrared (IR) spectroscopy, X-ray fluorescence spectroscopy (XRF), and scanning electron microscopy (SEM). Following the microwave heating, the vermiculite was characterized using XRD, IR spectroscopy, and SEM. Microwave irradiation of the vermiculite sample caused structural changes such as loss of crystallinity and disorder, as revealed by the XRD patterns, but did not cause expansion. Results from SEM and IR spectroscopy showed that the microwave heating did not cause profound alterations to the morphology, clay structure, and chemical composition of the vermiculite.

Resumo Este estudo propôs o desenvolvimento de uma membrana eficiente composta por zeólita-alumina a ser utilizada na separação óleo/água de efluentes contaminados por processos de extração de óleo. Os esforços feitos para cuidar do meio ambiente e descontaminar reservas de água são extremamente valiosos e constantemente atualizados. Pouca pesquisa foi feita sobre este assunto e este estudo contribuiu para remediar essa falta. A tecnologia de membrana é uma alternativa razoável para procedimentos convencionais, se economia e ecossustentabilidade forem consideradas. O objetivo deste estudo foi examinar o desempenho da membrana compósita produzida através de mistura mecânica. O potencial da membrana compósita (zeólita NaA/gama-alumina) para separar as emulsões óleo/água foi testado. Os resultados obtidos demonstraram que a membrana compósita é uma excelente alternativa para o processo de separação da emulsão óleo/água; as membranas são alternativas eficientes e de baixo custo para o tratamento de efluentes oleosos.

Abstract This study proposed the development of an efficient membrane composed of zeolite-alumina to be used for water-oil separation of wastewater effluents contaminated by oil extraction processes. The efforts made to care for the environment and to decontaminate bodies of water are extremely valuable and constantly being updated. Little research has been done on this subject and this study contributed to remedying this lack. Membrane technology is a reasonable alternative to conventional procedures if economics and eco-sustainability are considered. The objective of this study was to examine the performance of a composite membrane produced through mechanical mixing. The potential of the composite membrane (NaA zeolite/gama-alumina) to separate oil-water emulsions was tested. The results obtained demonstrated that the composite membrane is an excellent alternative for the oil/water emulsion separation process; the membranes are efficient and low-cost alternatives for treating oily wastewater.

Cadmium is a heavy metal which is found in the soil, air and food. It is present in everyday life and currently it is being implicated as a toxic, teratogenic and carcinogenic agent. It causes lesions to several organs of humans and animals alike. This work aims to investigate the toxic effects on fetuses of dams exposed to cadmium chloride treatment. Ten pregnant rats were divided into two groups. Five rats, the study group, received an intraperitoneal administration of cadmium chloride at 5 mg/Kg body weight on the 10th day of pregnancy and the other five, the study group, received a solution of 0.85% sodium chloride at the same dose and at the same application site. The fetuses together with the placentas and umbilical cords were collected on the 20th day of pregnancy. The administration of cadmium chloride caused a significant reduction in the sizes of both the fetuses and the placenta. The lengths of the umbilical cords were also shorter in animals of the study group when compared with the control group. This study also evaluated the morphological alterations caused in the proximal and distal convoluted renal tubules and collectors as well as the renal glomerular cells. Morphometry evidenced significant alterations in the proximal tubules and the glomerular cells and to a lesser degree in the distal tubules. The brush-border membrane cells were seen to be very sensitive and displayed some alterations. The glomeruli presented with edema and the Bowman's capsules were also affected

El cadmio es un metal pesado que se encuentra en la tierra, aire y alimentos. Está presente en forma coditiana todos los días de la vida y actualmente es catalogado como un tóxico, teratogénico y agente carcinogénico. El cadamio causa numerosas lesiones a los órganos humanos y animales. Este trabajo tiene como objetivo investigar los efectos tóxicos en fetos de ratas expuestas a tratamiento con cloruro de cadmio. 10 ratas preñadas fueron divididas en dos grupos. Cinco ratas recibieron por administración intraperitoneal 5 mg/Kg de cloruro de cadmio por peso corporal, durante 10 días de preñez y otras cinco ratas recibieron bajo las mismas condiciones del otro grupo, una solución de cloruro de sodio al 0.85% . Los fetos fueron extraídos junto con las placentas y funículos umbilicales a los 20 días de preñez. La administración del cloruro de cadmio causó una reducción significativa en los pesos de los fetos y placentas. La longitud del funículo umbilical fue más corta en el grupo experimental que en el grupo control. El estudio evaluó las alteraciones morfológicas causadas en los túbulos proximal, distal, contorneados y colectores renales como también en las células del glomérulo renal. La morfometría evidenció alteraciones significativas en los túbulos proximales y en las células glomerulares y, en menor grado, en los túbulos distales. El borde en cepillo de la membrana celular se observó muy sensible y se visualizaron algunas alteraciones. Los glomérulos se presentaron con edema y la cápsula del glomérulo fue también afectada