Water pollution has generated the need to develop technologies to remove industrial pollutants. Adsorption has been recognized as one of the most effective techniques for effluent remediation. In this study, parts (stem and leaves) of a problematic aquatic weed, the water hyacinth (Eichhornia crassipes), were separated to produce a bioadsorbent. The objective was to evaluate the adsorption of a cationic dye, methylene blue (MB), in an aqueous solution of the biomass from different parts of the water hyacinth (Eichhornia crassipes) plants. The materials were characterized through techniques of infrared spectroscopy, scanning electron microscopy, X-ray diffractometry, and thermogravimetric analysis, before and after the material adsorption. Water hyacinth biomasses presented adsorption capacity above 89%, and the kinetics was faster for stem biomass. The kinetic study found that the adsorption process is better described by the pseudo-second-order model, and the adjustments of the isotherm experimental data indicated that both materials are favorable for adsorption. Therefore, water hyacinth bioadsorbent represents a renewable resource with potential for effluent treatment.

Rapid industrial development has led to the use of numerous dyes responsible for significant water pollution worldwide. Adsorbents have been developed to treat these waters, mainly in the form of activated biochar, which has several advantages, one of which is its good surface characteristics, such as high surface area and pore volume. The objective of the investigation was to analyze the efficiency of removing the methylene blue model dye in aqueous solutions through the adsorption process using biochar chemically activated from the leaf and stem of water hyacinth (Eichhornio crassipes) as a bioadsorbent. This study carbonized the stem and leaf containing zinc chloride at 600 °C. The materials were characterized by different techniques and were tested for their ability to adsorb methylene blue. The activated stem and leaf biochars removed approximately 285.71 and 322.58 mg g⁻¹ of the dye, respectively, indicating that the adsorption is more significant in the leaf. Pseudo-second-order kinetics was the most suitable model to describe dye adsorption on biochars, and the experimental isotherm data fit the Langmuir model. It is concluded that the application of activated water hyacinth biochar is a renewable resource with the potential for effluent treatment.

Um dos grandes desafios da investigação em educação é o fato de pesquisar sobre as múltiplas relações entre o uso de tecnologias e a sala de aula. Ao levarmos em consideração o atual contexto de pandemia, percebemos que a busca por respostas às inquietações relativas à implementação das Atividades Remotas ganha ainda mais importância na comunidade científica. Tendo o que foi mencionado anteriormente, este trabalho apresenta como Objetivo Geral: Compreender os dilemas e desafios na implementação das Atividades Remotas de Ensino Aprendizagem no IFPI, Campus Floriano. Para tanto, o estudo consistiu de uma pesquisa qualitativa, documental, cuja forma de abordagem foi a Etnometodologia, tendo como procedimentos a Observação Participante, a Entrevista Narrativa e o Ciclo de Políticas, tendo como lócus o Instituto Federal do Piauí – IFPI, Campus Floriano e como interlocutores, três acadêmicos do curso de Licenciatura em Matemática. O trabalho evidenciou que o IFPI, embora tenha trabalhado para regulamentar as atividades não-presenciais e para buscar a diminuição das desigualdades apresentadas no acesso às atividades remotas o IFPI, por meio de instrumentos como o “auxílio conecitividade”, na prática, vivenciou o surgimento de muitos dilemas de cunho pessoal, social e pedagógico por parte dos alunos, bem como desafios didáticos por parte dos professores.

Given the increase in environmental pollution, especially of water, the emergence of studies that seek to develop strategies to mitigate/treat such effects have gained prominence in the world scientific community. Among the numerous adsorption processes, those made from biochar production stand out. This study analyzed the adsorption properties of the blue methylene model dye in the aqueous solution of biochar and activated biochar developed from pequi (Caryocar brasiliense) endocarp. The biochar was characterized, before and after adsorption, by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometry (XRD), and thermogravimetric analysis (TG). The surface load of the materials was performed by the point of zero charge (pH_PZC) method. The study also included analyses of contact time parameters and adsorbed concentration in the adsorption process. Morphological analysis showed that a more significant and profound number of fissures and pores appeared in the activated biochar compared to the biochar. Residual mass analysis evidenced that biochar lost about 15% more mass than the activated biochar, indicating that activation occurred satisfactorily. The adsorption process was well adjusted by pseudo-second-order kinetics and Langmuir’s isothermal model. The activated biochar achieved an excellent adsorption capacity of 476.19 mg.g⁻¹, thus demonstrating to be a sound system for removing dyes from an aqueous medium.

Water pollution remains a global problem that urges researchers to develop new technologies aimed at environmental restoration. Here, this study aimed at obtaining an activated biochar from pequi almonds for dye removal. Before and after adsorption, the materials underwent characterization using techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Raman spectroscopy, and thermogravimetric analysis (TG). The biochar from the pequi almond was called BA, and the activated biochar from the pequi almond was called ABA. The influence of the pH, contact time, and adsorbate concentration on adsorption was investigated using the dye methylene blue. The morphological assessment revealed higher cracks and pores in the ABA than in the BA. The TG showed that the BA lost approximately 19% more mass than the ABA, indicating that activation occurred. The activation contributed to the decrease in the degree of disorder in the BA because of the increased number of graphitic carbon atoms (ordered) in the ABA, as observed via Raman. The adsorption kinetics followed a pseudo-second-order model, while the adsorption isotherms followed the Langmuir model. The BA adsorption capacity was 500.00 mg g⁻¹, constituting a robust solution for dye removal from aqueous environments. Therefore, this implies the success of the process.

Diante das possibilidades de ação educativa que busquem alternativas aos modelos tradicionais, merece destaque o uso da ludicidade. Nessa perspectiva, estudos que abordem o uso de atividades lúdicas, em especial os jogos, vêm ganhando destaque nas pesquisas relativas ao ensino de ciências, em particular no ensino de citologia. Desta maneira, este trabalho apresenta como objetivo geral desenvolver uma proposta de jogo de tabuleiro que auxilie no ensino de citologia para alunos da educação básica. Para tanto, a pesquisa foi composta de uma Revisão Sistemática, seguida de uma Prospecção Tecnológica e culminou na confecção de um protótipo de jogo que auxilie no ensino de citologia. Os resultados do trabalho apontam para a necessidade tanto de novas propostas educativas sobre o uso de jogos para o ensino de citologia, tendo em vista a existência de poucos trabalhos referentes à temática no banco de dados da Scielo, quanto de registros de patentes resultantes de propostas educativas semelhantes à que é abordada nesse artigo.