This research aimed to evaluate the air quality, by determining the concentrations of PM 2.5-10 , PM 2.5 and the metallic elements Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg in the leaf part of ryegrass (Lolium multiflorum) in an area close to Schmidt Stream, at the lower section of Sinos River Basin (SRB), in a research campaign of six months, from October 2013 to March 2014. The particles collected in the PM sampling were analyzed by Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray Spectrometry (EDS), in order to study their morphology and chemical composition. The mean concentration of PM 2.5-10 was 9.1 µg m . Concentrations of metallic elements, especially Pb, Cr and Zn, were classified as Class 4 (very high pollution levels), according to the classification proposed by Klumpp et al. (2004). Chemical and morphological analysis of PM revealed the presence of particles of biological origin, soot (Cr, Fe, Ni, Zn, Cd, Hg and Pb), salts (KCl) and soil resuspension (Al and Si). The integrated study methodology, employing environmental variables, such as PM and ryegrass, can be of help in the preparation of wide-ranging environmental diagnoses, in addition providing information needed to develop precautionary measures designed to minimize the effects of atmospheric pollution that takes into consideration the environment's supportive capacity and environmental quality.Keywords: air pollution, particulate matter, biomonitoring, lolium multiflorum, mev/eds. Klumpp et al. (2004). A caracterização química e morfológica das partículas coletadas revelou a presença de fuligem (Cr, Fe, Ni, Zn, Cd, Hg e Pb), materiais biológicos, cristais salinos (KCl) e partículas ressuspensas de poeira do solo (Al e Si). Estudos integrados empregando variáveis ambientais como o MP e o biomonitoramento com azevém podem auxiliar na elaboração de diagnósticos ambientais robustos, além de fornecer informações para o desenvolvimento de medidas de precaução que considerem a capacidade de suporte do meio ambiente e que visem à minimização dos efeitos prejudiciais da poluição atmosférica. Concentrações de MPPalavras-chave: poluição atmosférica, material particulado, biomonitoramento, lolium multiflorum, mev/eds.
One of the biggest environmental problems existing today is air pollution, which is characterized by the presence of toxic gases and metal pollutants, the latter of which is generally associated with emissions of particulate matter (PM) from industries or automotive vehicles. Biomonitoring is a method that can be used to assess air pollution levels because it makes it possible to determine what effects these air pollutants cause in living organisms and their responses. The species Lolium multiflorum Lam., known as ryegrass, is considered a good bioindicator of metals, since it accumulates these substances during exposure. This study proposes to conduct an integrated assessment of air quality using two different monitoring methodologies: biomonitoring with L. multiflorum and active monitoring in areas with different levels of urbanization and industrialization. Concentrations found in ryegrass plants revealed high levels of Pb, Cr, Zn, and Cu, indicating that vehicular and industrial emissions were the main sources of pollution. Analysis of PM also revealed soot and biogenic particles, which can transport metals. Therefore, with the proposed method, the anthropogenic impact on air pollution in the investigated area could be clearly demonstrated.
Recycling Footwear Industry Waste and Evaluation the Deterioration in SoilAbstract: The production of footwear generates various residues, such as cotton fabric flaps and rubber chips, which are materials that have characteristics that make it difficult to recycle. Thus, the objective of this study is the mechanical recycling of these residues, obtaining blends of these residues with Capro-PU and EVA. They are processed mechanically by comminution, extrusion and pelletizing, obtaining chemically analyzed materials and subsequently submitted to the injection and lamination processes in order to observe the characteristics in the form of industrialized products. The materials were characterized by Scanning Electron Microscopy, thermogravimetric analysis and CO 2 release rate evaluation. The recycled materials were subjected to the lamination and injection processes where they were evaluated according to characteristic tests for the production of assembly insoles. By the TGA, it was possible to verify that the blends had a greater thermal stability when compared to the pure consumables. Regarding the mechanical tests, all blends were within the limits established by the PFI and showed values of CO 2 release rate higher than the values of the test only with the fabric, since this is a biodegradable material. Thus, it is observed that the present study is a breakthrough for materials processing technology, creating new products with suitable characteristics for manufacturing processes and presenting microbiological degradation capacity, when discarded in soil.Keywords: Recycling; Mechanical processing; Footwear; Solid waste; Microbiological degradation. ResumoA produção de calçados geram diversos resíduos, tais como retalhos de tecido de algodão e aparas de borracha, que são materiais que apresentam características que dificultam sua reciclagem. Assim, o objetivo deste estudo é a reciclagem mecânica destes resíduos, obtendo blendas destes resíduos com Capro-PU e EVA. Sendo processados mecanicamente por cominuição, extrusão e peletização, obtendo-se materiais analisados quimicamente e posteriormente submetidos aos processos de injeção e laminação a fim de observar as características na forma de produtos industrializados. Os materiais foram caracterizados por ensaios de Microscopia Eletrônica de Varredura, análise termogravimétrica e avaliação da taxa de liberação de CO 2. Os materiais reciclados foram submetidos aos processos de laminação e injeção onde foram avaliados de acordo com ensaios característicos para a produção de palmilhas de montagem. Pelo TGA foi possível verificar que as blendas ficaram com uma maior estabilidade térmica quando comparado aos insumos puros. Em relação aos ensaios mecânicos, todas as blendas ficaram dentro dos limites estabelecidos pelo PFI e apresentaram valores de taxa de liberação de CO 2 superiores aos valores do ensaio somente com o tecido, visto que este é um material biodegradável. Desta forma, observa-se que o presente estudo é um avanço para a tecnologia de processamento de mater...
The Luíz Rau stream is one of the main streams of Novo Hamburgo. In the stream industrial effluents are released from various sectors, from paint and adhesive industries, metallurgy and leather industry, besides receiving a large amount of domestic sewage. The emissions of these pollutants contribute to decrease water and sediment quality. Within this context, this study evaluated the conditions of the Luíz Rau stream bed sediments, with the determination of the metals like cadmium, lead, chromium and nickel, in depth. To perform the evaluation three points were chosen for sampling along the stream course. The sampling sites were identified as Point A, in Roselândia district and this corresponds to one of the springs and therefore considered as reference value, Point B, in Santo Afonso district being a midpoint of the stream, and Point C also located in Santo Afonso district, near the outfall in Rio dos Sinos river. Cadmium was not detected in any point. At the A and C points chromium was the metal observed in higher concentration in the sediment, up to 45.14 mg kg -1 concentration. In the B point, the metal that was observed in the highest amount was nickel in the concentration of 20.69 mg kg -1 .Keywords: sediment, Luíz Rau stream, environmentally available metals, collection of sediment in depth. Avaliação preliminar de metais pseudo-totais e biodisponíveis em profundidade no sedimento do arroio Luíz Rau em Novo Hamburgo (RS)Resumo O arroio Luíz Rau é um dos principais arroios de Novo Hamburgo, e um importante afluente do Rio dos Sinos. Nele são lançados efluentes industriais dos mais diversos setores, desde indústrias de tintas e adesivos, metalurgia e da indústria do couro, além de receber uma grande quantidade de esgoto doméstico. As emissões destes poluentes contribuem para uma diminuição na qualidade da água e dos sedimentos. Dentro deste contexto, este trabalho avaliou as condições do sedimento do arroio Luíz Rau, com a determinação dos metais cádmio, chumbo, cromo e níquel em profundidade, nas formas pseudo-total e biodisponível. Para a realização desta avaliação, foram escolhidos três pontos para coleta de amostras ao longo do percurso do arroio. Os pontos foram identificados por Ponto A, no bairro Roselândia, sendo que este corresponde a uma das nascentes e por isso considerado como ponto branco, o Ponto B, no bairro Santo Afonso, sendo um ponto intermediário do arroio, e o Ponto C, também localizado no bairro Santo Afonso, próximo à foz, junto ao Rio dos Sinos. O cádmio não foi detectado em nenhum dos pontos amostrados. Nos pontos A e C, o cromo foi o metal observado em maior concentração no sedimento, com concentração de até 45,14 mg kg Palavras-chave: sedimento, arroio Luíz Rau, biodisponibilidade de metais, coleta de sedimentos em profundidade.
Os dejetos líquidos de suínos (DLS) e o extrato pirolenhoso (EP) geralmente são utilizados como fertilizantes em áreas agrícolas. Quando dispostos na natureza de forma inadequada, eles podem causar impactos ambientais negativos, tanto para o solo, quanto para os lençóis freáticos. Este estudo propõe pesquisar o efeito da incorporação do extrato pirolenhoso no solo, juntamente com DLS, na mobilidade dos metais Cu e Zn e contaminantes tipicamente presentes nos DLS. Os experimentos foram conduzidos em colunas de solo com adição de EP e DLS, em concentrações determinadas, para verificar a lixiviação dos metais. As colunas foram submetidas a regas regulares. Os percolados foram analisados por espectrometria de absorção atômica para a quantificação dos metais estudados. Os resultados mostraram o perfil de lixiviação de Cu e Zn. Pode-se verificar que a combinação da adição do DLS e do EP ao solo diminui a lixiviação dos metais analisados.
ResumoO processo de galvanização a zinco utiliza como principal passivante o metal cromo na sua forma hexavalente. O presente trabalho estuda a remoção por zeólitas do íon cromo (VI) do efluente de uma indústria metalúrgica. Devido a grande concentração de Cr (VI) na amostra, primeiramente foi realizada uma redução deste metal utilizando metabissulfito de sódio, que é o agente redutor e de precipitação ideal para efluentes contendo concentrações de Cr(VI) acima de 100 mg L EVALUATION OF THE USE OF ZEOLITES IN THE REMOVAL OF CHROMIUM (VI) OF WASTEWATER METALS INDUSTRY AbstractThe process of zinc planting uses as the main passivating the metal hexavalent chromium. This paper studies the removal of chromium (VI) of the wastewater from a metallurgical industry by zeolites. Due to the high sample concentration in Cr (VI), was first performed a reduction of this metal using sodium metabisulfite, which is the ideal reduction and precipitating agent for wastewater containing concentrations of Cr(VI) above 100 mg L -1. At lower concentrations the precipitate has a low sedimentation kinetics, requiring a polish with a tertiary treatment. This study was conducted in fixed-bed column where were filtred solutions with concentrations of Cr(VI) ranging from 0.5 to 10 mg L -1 . The wastewater was applied at the top of the column and removed from the bottom. From the adsorption data was calculated the adsorption isotherms (Langmuir and Freundlich). The Langmuir model obtained was significant and predictive with 97.93 % reliability. The maximum capacity of the zeolite to remove chromium (VI) was estimated at 0.02 mg Cr(VI) g -1 zeolite..
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