Advanced oxidation processes (AOPs) constitute important, promising, efficient, and environmental-friendly methods developed to principally remove persistent organic pollutants (POPs) from waters and wastewaters. Generally, AOPs are based on the in situ generation of a powerful oxidizing agent, such as hydroxyl radicals (•OH), obtained at a sufficient concentration to effectively decontaminate waters. This critical review presents a precise and overall description of the recent literature (period 1990–2012) concerning the main types of AOPs, based on chemical, photochemical, sonochemical, and electrochemical reactions. The principles, performances, advantages, drawbacks, and applications of these AOPs to the degradation and destruction of POPs in aquatic media and to the treatment of waters and waste waters have been reported and compared.

Advanced Oxidation Processes in Water/Wastewater Treatment: Principles and Applications. A Review

Electrochemically Assisted Remediation of Pesticides in Soils and Water: A Review

Electrochemical oxidation is an effective wastewater treatment method. Metal oxide-coated substrates are commonly used as anodes in this process. This article compiles the developments in the fabrication, application, and performance of metal oxide anodes in wastewater treatment. It summarizes the preparative methods and mechanism of oxidation of organics on the metal oxide anodes. The discussion is focused on the application of SnO2, PbO2, IrO2, and RuO2 metal oxide anodes and their effectiveness in wastewater treatment process.

Metal oxide-coated anodes in wastewater treatment

Electrochemical reduction of halogenated organic compounds is gaining increasing attention as a strategy for the remediation of environmental pollutants. We begin this review by discussing key components (cells, electrodes, solvents, and electrolytes) in the design of a procedure for degrading a targeted pollutant, and we describe and contrast some experimental techniques used to explore and characterize the electrochemical behavior of that pollutant. Then, we describe how to probe various mechanistic features of the pertinent electrochemistry (including stepwise versus concerted carbon–halogen bond cleavage, identification of reaction intermediates, and elucidation of mechanisms). Knowing this information is vital to the successful development of a remediation procedure. Next, we outline techniques, instrumentation, and cell designs involved in scaling up a benchtop experiment to an industrial-scale system. Finally, the last and major part of this review is directed toward surveying electrochemical studi...

Electroreductive Remediation of Halogenated Environmental Pollutants.

Adsorption behavior and mechanism of five pesticides on microplastics from agricultural polyethylene films.

This report shows an unexpected toxicity decrease during atrazine photoelectrodegradation in the presence of NaCl. Atrazine is a pesticide classified as endocrine disruptor occurring in industrial effluents and agricultural wastewaters. We therefore studied the effects of the degradation method, electrochemical and electrochemical photo-assisted, and of the supporting electrolyte, NaCl and Na2SO4, on the residual toxicity of treated atrazine solutions. We also studied the toxicity of treated atrazine solutions using Artemia nauplii. Results show that at initial concentration of 20 mg L−1, atrazine was completely removed in up to 30 min using 10 mA cm−2 electrolysis in NaCl medium, regardless of the electrochemical method used. The total organic carbon removal by the photo-assisted method was 82% with NaCl and 95% with Na2SO4. The solution toxicity increased during sole electrochemical treatment in NaCl, as expected. However, the toxicity unexpectedly decreased using the photo-assisted method. This finding is a major discovery because electrochemical treatment with NaCl usually leads to the formation of toxic chlorine-containing organic degradation by-products.

Unexpected toxicity decrease during photoelectrochemical degradation of atrazine with NaCl

Modelo do estudo: Abordagem qualitativa de pesquisa Objetivo: foi utilizado recurso audiovisual (filmes)para propiciar reflexoes, discussoes e atualizacao de professores, alunos e profissionais da saude emtemas sociais pertinentes as areas da saude e educacao. Metodologia: o projeto foi estruturado em formade curso de difusao com cinco encontros, entre agosto e dezembro de 2008. Foram abordados temasrelevantes em Saude e Educacao (fome, violencia escolar, gravidez na adolescencia, processo saudedoenca e drogas na adolescencia) e foram convidados especialistas em cada tematica para debate. Oinstrumento utilizado para captar as percepcoes dos participantes foi um questionario de 14 questoessemi-estruturadas e ao final de cada encontro foi solicitada a entrega de relatorio. Foi realizada AnaliseTematica de Narrativa de material proveniente dos relatorios individuais de reflexao. Resultados: osencontros tiveram a presenca de 49 participantes (estudantes de graduacao, professores da rede municipal de ensino, profissionais da area da saude, pos-graduandos e docentes do ensino superior). Naanalise do material narrativo advindo das questoes abertas dos relatorios individuais de reflexao foipossivel levantar dois blocos de categorias, sendo que o primeiro deles destacou as expectativas que osparticipantes tinham antes de iniciar o projeto CineSocial e o segundo bloco levantou a opiniao dosparticipantes sobre a relevância do curso. Discussao e Conclusoes: o uso do cinema possibilitou acirculacao dos conhecimentos, tornou possivel a difusao de experiencias, corroborou a ideia de quedocumentarios assim como filmes de ficcao podem exprimir os conhecimentos orientados pela Ciencia.Pensar a arte do cinema nao foi a prioridade dessa experiencia, a prioridade foi pensar a vida, a sociedade, a escola, a saude, a exclusao social e temas do cotidiano presentes dentro ou fora das escolas.

Cinema: uma ferramenta pedagógica e humanista para temas em Saúde-Educação. A experiência do CineSocial

Study design: The approach to the research was qualitative. Objective: we used the audiovisual resources (movies) to make teachers, students and health professionals reflect, discuss and update social subjects relevant to health and education. Methodology: The Project was structured as a course with five meetings that took place between 2008 August and December. Subjects relevant to Public Health and Education were focused (hunger, school violence, teenage pregnancy, health-disease process and teenage drug abuse); for each theme, specialists were invited. The instrument used to acquire the participant perceptions was a questionnaire with 14 semi-structured questions and at the end of each meeting, a report was requested. A Thematic analysis of narrative was conducted with the material from the individual reflection report. Results: The meeting had the presence of 49 participants (undergraduates, public teachers, health professionals, graduates and professors). In the analysis of the narrative open question material from the individual reflection report, we could identify two sets of categories: the first one identified was the participants' expectancy before beginning the CineSocial project and the second one identified was the participants' opinions about the course relevance. Discussion and Conclusions: The cinema use enabled knowledge flow and experience diffusion; it also corroborated the idea that not only documentaries and fiction films could express the knowledge aimed by Science, but other types of cinema as well. Focusing on cinema was not the priority of this experience, the priority was focus on life, society, school, exclusion, current subjects present inside or outside of the school.

Cinema: an humanist and pedagogical tool for themes in Health-Education. The experience of CineSocial

ABSTRACT In order to produce bulbs or seeds, onion plants depend on genotype X environment interaction. Thus, breeders shall select the genotypes based on the climatic conditions of each producing region. This study aimed to evaluate 17 experimental onion hybrids and two commercial genotypes (‘Bella Dura’ and ‘Buccaneer’), based on agronomic, physicochemical attributes of the bulbs and resistance to early flowering under subtropical conditions. Joint analysis of variance and phenotypic divergence estimated through principal component analysis (PCA) and Ward’s hierarchical clustering were performed. We observed that the time of transplantation affected the agronomic traits more than the physicochemical traits, not affecting the percentage of early flowering of the genotypes. The first transplant season provided higher bulb productivity, whereas the second season reduced the cycle and productivity. Hybrids H1, H17 and ‘Buccaneer’ showed flowering rate lower than 3%. Among the experimental hybrids, H2 showed higher productivity when comparing with commercial cultivars, and H1, H12 and H14 were equivalent to them. However, H12 showed the highest early flowering rate (43%). Thus, considering the experimental genotypes evaluated under subtropical conditions, H1, H2, and H14, showed potential for commercial use or as potential parents in advancing the breeding program, as they stood out for presenting good yield, bulb quality and low percentage of early flowering.

Ricardo L. R. Santos

Papers

Unexpected toxicity decrease during photoelectrochemical degradation of atrazine with NaCl

Cinema: uma ferramenta pedagógica e humanista para temas em Saúde-Educação. A experiência do CineSocial

Cinema: an humanist and pedagogical tool for themes in Health-Education. The experience of CineSocial

Productivity, physicochemical quality and early flowering resistance of experimental onion hybrids