RESUMO
Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.
Assuntos
Compostos Azo/toxicidade , Biodegradação Ambiental , Descontaminação/métodos , Espectrometria de Massas em Tandem/métodos , Recuperação e Remediação Ambiental/métodos , Águas Residuárias , Fotoquímica , Têxteis/toxicidade , Microscopia Eletrônica de Varredura , Catálise , Domínio Catalítico , Espectrometria de Massas por Ionização por Electrospray , Corantes , Fotobiorreatores , Modelos TeóricosRESUMO
ABSTRACT Sludge oil derived from the effluent generated in poultry abattoirs offers a promising biomass for the production of biodiesel. In this work, determination was made of its physicochemical characteristics, including acidity, density at 20ºC, peroxide index, moisture content, and saponification index, together with evaluation of a route for its conversion to biodiesel.
Assuntos
Biocombustíveis , Matadouros , Biomassa , Energia RenovávelRESUMO
Trata-se de estudo retrospectivo sobre 12 casos de infarto cerebelar. Sete pacientes eram do sexo masculino e cinco, do feminino. A idade variou entre 46 e 76 anos, com média de 54 anos. As causas foram hipertensão arterial sistêmica em seis, endocardite bacteriana em três e desconhecida em outros três. A cefaléia foi sintoma presente em dez pacientes, vômitos em oito, tonteira em oito, ataxia da marcha em sete e vertigem em quatro. A tomografia do crânio foi útil no diagnóstico e conduta. Onze pacientes foram submetidos a tratamento conservador. Derivação ventricular externa e craniectomia suboccipital foram realizadas em um paciente. Houve quatro óbitos. O prognóstico esteve diretamente relacionado ao nível de consciência por ocasião da admissão, da extensão do infarto e da idade do paciente.