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Obesidade infantil – Caraterização de uma população com seguimento hospitalar

Introdução: A obesidade infantil está associada a grave morbilidade, a motivação para o tratamento geralmente é baixa e os resultados são habitualmente desanimadores. Objetivos: Caraterizar uma população com excesso de peso e obesidade inscrita na consulta de endocrinologia pediátrica e avaliar a existência de comorbilidades associadas. Material e Métodos: Estudo descritivo dos casos de peso excessivo (pré-obes...

End-of-life Zn–MnO2 batteries: electrode materials characterization

Physical and chemical characterization of several sizes and shapes of alkaline and saline spent Zn–MnO2 batteries was carried out, aiming at contributing for a better definition of the applicable recycling processes. The characterization essays included the mass balance of the components, cathode and anode elemental analysis, the identification of zinc and manganese bearing phases and the morphology analysis of...

Characterization of Spent Ni-MH Batteries

Spent Ni-MH batteries are not considered too dangerous for the environment, but they have a considerable economical value due to the chemical composition of electrodes which are highly concentrated in metals. The present work aimed at the physical and chemical characterisation of spent cylindrical and thin prismatic Ni-MH batteries, contributing for a better definition of the recycling process of these spent pr...

Recycling of exhausted batteries and EAF dusts by leaching with several aqueous...

Zinc is a base metal present in several products of general use, and therefore found in numerous residues and end-of-life products. The two main sources of zinc containing wastes are spent Zn-MnO2 portable batteries and electric arc furnace (EAF) dusts from steelmaking plants. The recovery of metals from these residues by appropriate recycling processes is mandatory due to environmental, economic and resource c...

Recycling of zinc bearing residues: leaching behavior of spent batteries and e...

Characterization of spent Ni-MH batteries

Leaching behavior of several zinc rich residues in a hydrometallurgical recycli...

The leaching of metals contained in spent Zn-MnO2 batteries and electric arc furnace (EAF) dusts using sulfuric acid solutions was studied, in order to evaluate the feasibility of simultaneous treatment of both wastes by a hydrometallurgical process. In both residues, a substantial quantity of zinc was solubilized (about 100% in batteries and 70-80% in EAF dusts) in diluted acid solutions and room temperature, ...

Integration of physical operations in the hydrometallurgical processing of spen...

The recycling of spent Zn-MnO2 batteries by hydrometallurgy involves the leaching of material previously treated by physical processing to allow the liberation of electrode particles and the separation of unwanted scrap. The integration of these physical operations with leaching is therefore crucial for the optimization of the process, allowing achieving high recovery yields of zinc and manganese and minimizing...

Leaching studies for metals recovery from printed circuit boards scrap

In this paper, the leaching behavior of the major metals present in printed circuit boards waste is evaluated, aiming at its recycling by hydrometallurgy. Several leachants were compared (sulfuric, hydrochloric and nitric acids, at 2 M H+ concentration), at temperatures of 25ºC and 90ºC and 4 hours of reaction time. Sulfuric acid leaching was not very promising concerning metals dissolution being only effective...

Preliminary results in the immunodiagnosis of tuberculosis in children based on...

The aim of this work was to study the difference in interferon gamma (IFN-gamma) production by T lymphocytes after early secretory antigen target 6 (ESAT-6) or purified protein derivate (PPD) stimulation in whole blood culture supernatants from children with suspected tuberculosis (TB) disease (n = 21), latent TB infection (n = 16) and negative controls (NC) (n = 22) from an endemic area in Brazil. The concentr...