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Effluents from textile processes, when discarded of inappropriately, have been shown to be a major environmental concern. In this way, different methods can be used, among them adsorption is an economical and efficient technique in the removal of dyes. Therefore, we propose to analyze the adsorptive capacity of bacterial cellulose (CB) against effluents containing the dye Remazol Black B (RBB). CB was produced by the bacterium Gluconacetobacter hansenii and characterized by the techniques of FTIR, DRX, TGA / DTG and pH (PCZ). The RBB removal tests were initially performed at different pHs. From the best experimental condition, new tests were performed at temperatures of 30, 40, 60 and 100 ± 2 °C, 150 rpm, pH 3.5, using 0.5 g of adsorbent in the concentrations of dye from 25 to 65 mg•L -1 . The kinetic study showed that the system balance was achieved in 80 minutes. The experimental data were better described by the pseudosecond order model. The equilibrium results showed that the experimental data fit the Langmuir model (qmax 17.513 mg•g -1 ). The thermodynamic parameters of adsorption showed that the process is exothermic, not spontaneous and also presented low system randomness. The activation energy (Ea) was 23.8 kJ•mol -1 characterizing physical adsorption. The residual water was not toxic to animal or microbial cells. Bacterial cellulose proved to be a good low-cost adsorbent, easy to acquire and which can be used in the adsorption process.

Em função do crescente conhecimento nas implicações sobre o meio ambiente, do aumento populacional e consumo exacerbado, o alto volume de resíduos gerados a serem dispostos de forma inadequada, tem favorecido como grandes desafios tanto para os gestores públicos quanto para a sociedade O objetivo do trabalho foi avaliar o local de destinação final dos resíduos sólidos urbanos gerados no Distrito Pilar em Jaguarari-BA. O trabalho foi desenvolvido no período de janeiro de 2016. A primeira etapa, foi realizada no local de destinação final dos resíduos, através de visitas e observações in loco do lixão à céu aberto, às quais permitiram descrever os principais impactos ambientais presentes no ambiente de destinação final dos resíduos, e através de entrevistas para os moradores que moram no entorno do lixão, e funcionários da prefeitura. De acordo com os resultados, observou-se que os principais impactos diagnosticados foram: Resíduos depositados de maneira irregular, contaminação do solo, e águas subterrâneas, riscos aos catadores e impacto na saúde pública.

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This study evaluates the removal of textile dyes using mixed adsorbents prepared by the growth of Aspergillus niger in orange peels. The highest azo dye removal efficiency was obtained at pH 2, solid: liquid ratio (1: 4 g·mL-1) and time of equilibrium of 250 minutes for each dye. The concentrations of Remazol Black B (RB) and Remazol Red (RR) in both synthetic textile effluents were between 25 mg·L-1 and 100 mg·L-1. The mixed adsorbent was characterized by X-ray diffraction (XRD), spectroscopy infrared region (FTIR) and scanning electron microscopy (SEM). The results indicated that there was a 100% removal of RB and 94.85% of RR at the concentration of 25 mg·L-1. At the concentration of 100 mg·L-1, the percentages of removal reached 98.87% for RB and 96.37% for RR, respectively. The proposed mixed adsorbent was able to remove the textile dyes, presenting adsorptive capacities of 20.77 mg·g-1 and 19.28 mg·g-1 for the dyes RB and RR. Regarding the adsorption kinetics, the experimental data showed that the pseudo second order model was the one that best explained the adsorptive process. For the equilibrium results, the Langmuir model and the Langmuir-Freundlich model were the ones that best fit the experimental data of RB and RR, respectively. The mixed adsorbent produced is a promising alternative for the treatment of textile effluents.

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Consumidoras em potencial, as crianças formam um grupo que precisa ser analisado na sua interação com as mensagens da propaganda, por possuir um jeito próprio de compor fantasia e realidade. Com base no conceito de recepção como lugar de produção da comunicação, conforme Jesús Martín-Barbero, a pesquisa focalizou como a criança entende as diferenças entre comerciais e programação da TV, assim como os elementos de atração, de retenção do produto, marca e personagem para refletir sobre a influência da propaganda. Dentre os métodos para levantamento de dados, trabalhou-se com discussão de grupo e técnica projetiva. Palavras-chave: Recepção; criança; televisão; propaganda; consumidor. ABSTRACT Children are potential consumers, who have their own way of composing fantasy and reality. They form a group that needs to be especially understood in their interaction with advertising messages. Based on Jesús Martín- Barbero´s concept for reception as the locus of production in communication, the present research aimed at seeing how children understand the differences between TV programs and comercials. By analyzing the elements that most attract them, identifying their product, character and brand retention, we reflect over the influence of advertising on children. In order to gahter data, group discussion and projective techniques were used. Keywords: Audience; child; television; advertisement; consumer.