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Avaliação da geração de biogás a partir de resíduos agroindustriais e emprego do biofertilizante na remediação de solos contaminados por hidrocarbonetos
No full textA utilização de combustíveis fósseis como fonte de energia pode gerar impactos ambientais tais como emissão de gases poluentes e contaminação de solos. Uma alternativa para minimização destes impactos é o aproveitamento do resíduo da biodigestão da matéria orgânica em ambiente anaeróbico, utilizado na produção de biogás. O uso desta tecnologia, além de gerar um gás com alto teor calorífico, produz um efluente estabilizado (biofertilizante) que, quando disposto em solos, tem o potencial de incrementar os nutrientes, tornando-os mais ricos e com maior desenvolvimento da comunidade microbiana. Em áreas onde estão localizados postos de gasolina, vazamentos de derivados de petróleo causam a contaminação dos solos, sendo necessário um tratamento que vise à redução das quantidades de poluentes e evite que esta contaminação escoe para os lençóis freáticos. A técnica de biorremediação pode ser uma alternativa eficiente e de baixo custo para o tratamento destes solos. Assim, o presente estudo teve por objetivo avaliar o potencial dos resíduos de uma indústria alimentícia e frigorífico de suínos e aves na geração de biogás e utilizar o biofertilizante obtido pelo processo de biodigestão anaeróbia na biorremediação de solos contaminados com gasolina. Os resíduos agroindustriais submetidos à digestão anaeróbia geraram aproximadamente 13L de biogás, dentre este volume, aproximadamente 10L foi de metano (CH4). As análises físico-químicas do biofertilizante mostraram redução dos sólidos totais (ST), demanda biológica de oxigênio (DBO), demanda química de oxigênio (DQO), carbono (C) e nitrogênio (N), confirmando que houve degradação da matéria orgânica pelos microrganismos. No experimento de biorremediação os tratamentos de solo contaminado (SC) e solo contaminado mais biofertilizante (SCB) apresentaram redução significativa dos hidrocarbonetos, todos variando de 80 a 100% de remoção. Ao longo do experimento, foi verificado que a detecção dos hidrocarbonetos em SCB foi menor que SC, fato que possivelmente ocorreu pela adição de matéria orgânica que auxilia na retenção dos hidrocarbonetos no solo. Com a análise dos dados apresentados, pode-se concluir que os resíduos da indústria alimentícia e frigorífico são bons produtores de biogás quando dispostos em ambiente anaeróbico e que o aumento de matéria orgânica em solos contaminados aumenta a retenção dos hidrocarbonetos neste ambiente e não influencia na velocidade de degradação dos mesmos.The use of fossil fuel as a source of energy can generate environmental impacts such as emission of pollutant gases and soil contamination. An alternative to minimize from these impacts is the use of waste from the biodigestion of organic material in anaerobic environment, used in the biogas production. The use of this technology, besides generating gas with a high calorific content, produces a stabilized effluent (biofertilizer) that, when arranged on soils, has the potential to increase the nutrients, making them richer and with a greater development of the microbial community. In areas where gas stations are located, leaks of petroleum products cause soil contamination, which needs a treatment aiming the reduction of the amounts of pollutants, and avoiding the contamination from flowing to the groundwater. The technique of bioremediation can be an efficient alternative and with a low cost for the treatment of these soils. Thus, this study aimed to assess the potential of the waste from a food industry and swine and poultry slaughterhouse in biogas generation and use bio-fertilizer obtained by the process of anaerobic biodigestion in bioremediation of soils contaminated by gasoline. The agro-industrial waste subjected to anaerobic digestion generated approximately 13L of biogas, from this volume, approximately 10L was of methane (CH4). The physicochemical analyses of the biofertilizer showed a reduction of total solids (TS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), carbon (C), and nitrogen (N), sustaining that there was degradation of organic material by the microorganisms. In the experiment of bioremediation, the treatments of contaminated soil (CS) and contaminated soil plus bio-fertilizer (CSB) showed a significant reduction of hydrocarbons, all of them varying from 80 to 100% of removal. Throughout the experiment, it was found that the detection of hydrocarbons in contaminated soil plus bio-fertilize was lower than in contaminated soil, fact that probably occurred due to addition of organic material that helps in the retention of hydrocarbons in the soil. With the analysis of the presented data, we can conclude that the waste of food industry and slaughterhouse are good biogas producers when they are in anaerobic environment, and that the increase of organic material in contaminated soils increases the retention of hydrocarbons in this environment and it doesn’t influence on the speed of their degradation
Identificação e caracterização de microrganismos visando maior eficiência na produção de biogás
Get PDFOs setores agrícolas e agroindustriais geram resíduos ricos em matéria orgânica, principalmente os dejetos animais. Estes, por sua vez, podem ser degradados por processos biológicos e aproveitados como biomassas na geração de bioenergia em sistemas de digestão anaeróbia. O uso de co-digestão pode otimizar a produção de biogás e metano e, ao final do processo, sevir como inoculante na iniciação dos processos de digestão anaeróbia. Neste sentido, o objetivo deste estudo foi desenvolver, caracterizar e avaliar a eficiência de inoculantes, utilizando co-digestão anaeróbica de diferentes resíduos do agronegócio como biomassa em temperatura controlada e ambiente, e formular um inoculante com uma mistura de microrganismos isolados visando otimizar a produção de biogás e metano. Para isto, foram preparados quatro inoculantes (constituídos de dejeto suíno, aves e bovino), que foram incubados anaerobicamente por 72 dias e aclimatados em temperatura controlada (35o C) e ambiente (28 ± 3,5° C). Um inoculante, em cada temperatura, foi alimentado com uma mistura de celulose microcristalina, gelatina, latose e resíduo de óleo de cozinha. Ao final, a identificação da comunidade microbiana mostrou que os inoculantes apresentaram diferenças importantes entre as duas temperaturas avaliadas, Bacteroidetes foi o filo mais representativo em inoculantes a 28° C e Firmicutes a 35° C, e destaca-se que o uso dos inoculantes (alimentado e não alimentado) melhora o
rendimento da produção de biogás e metano 28 °C, atingindo valores semelhantes na faixa ideal de temperatura (35° C). O isolamento de 10 microrganismos anaeróbicos facultativos dos inoculantes mostrou que eles pertencem ao filo Firmicutes, famílias Paenibacillaceae e Bacillaceae. A adição desta mistura de microrganismos não melhorou a produção de biogás nas diferentes temperaturas, no entanto, mais testes
serão necessários para avaliar o potencial destes microrganismos. A partir dos resultados obtidos pode-se concluir que o uso de inoculantes em sistemas de digestão anaeróbica melhora a eficiência da produção de biogás e metano em temperaturas inferiores (28 °C ±3,5) a considerada ideal (35 oC), o que pode permitir o uso desse tipo de produção de energia nas regiões que apresentam temperaturas ligeiramente mais baixas.The agricultural and agroindustrial sectors generate waste rich in organic matter, mainly animal waste. These wastes can be degraded by biological processes and used as biomass in the generation of bioenergy. The use of co-digestion can optimize the production of biogas and methane and, at the end of the process, the biomass can be used as inoculant for a new anaerobic digestion process. In this sense, the objective of this study was to develop, characterize and evaluate the efficiency of inoculants, using anaerobic co-digestion of different residues from agribusiness as biomass at controlled and environmental temperature, and to formulate an inoculant with a mixture of isolated microorganisms in order to optimize production of biogas and methane. For
this pourpose, four inoculants (composed by swine, poultry and bovine manures) were incubated anaerobically for 72 days and acclimatized under controlled (35 oC) and environmental (28 ± 3.5 °C) temperatures. One inoculant of each temperature was fed with a mixture of microcrystalline cellulose, gelatin, latose and cooking oil residue. In the end of inoculat preparation, the identification of the microbial showed that inoculants presented important differences between the two temperatures evaluated, Bacteroidetes was the most representative phylum in inoculants at 28 °C and Firmicutes at 35 °C. The use of inoculants (fed or non-fed) improves the yield of biogas and methane production at 28 ° C, reaching similar values to ideal temperature range (35 °C). The isolation of 10 facultative anaerobic microorganisms from the inoculants showed that they belong to the phylum Firmicutes, Paenibacillaceae and Bacillaceae families. The addition of mixture of these microorganisms did not improve the biogas production at different temperatures, however, more tests will be needed to evaluate the potential of these microorganisms. From the results obtained, it can be concluded
that the use of inoculants in anaerobic digestion systems improves the efficiency of the biogas production and methane at lower temperatures (28 ° C ±3.5) than that considered ideal (35 °C), which may allow the use of this type of energy production in regions with slightly lower temperatures
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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