Mycobacterium celatum is a recently described, slowly growing mycobacterium of still undefined clinical relevance. A retrospective study of seven patients was conducted to further elucidate the clinical presentation and prognosis of infection due to M. celatum in patients with AIDS. Three patients had an exclusively pulmonary infection and 3 had disseminated infection (including 2 patients with pulmonary and extrapulmonary involvement), and 1 patient had an exclusively extrapulmonary disease. Fever, weight loss, and productive cough lasting for >2 weeks were the most common symptoms. Chest radiographs showed diffuse or focal interstitial infiltrates without cavitation. The recovery of M. celatum from one patient was definitively determined to be clinically irrelevant. Our findings indicate that M. celatum may cause serious disease in patients with advanced human immunodeficiency virus-related immunosuppression. M. celatum infection appears to be responsive to antimycobacterial chemotherapy; however, further studies are needed to establish the optimal drug combination for this indication.
RESUMOO uso da biomassa para fins energéticos tem sido destaque como forma de reduzir a dependência energética de fontes não renováveis. A macaúba, espécie Acrocomia aculeata (Jacq.) Lodd. ex Martius, é uma palmeira arborescente. Possui um grande potencial energético a partir do processamento de seus frutos. O objetivo desse trabalho foi caracterizar os resíduos da macaúba após o processamento dos frutos, a fim de avaliar a sua utilização in natura e como carvão vegetal. O endocarpo apresentou teor de carbono fixo, poder calorífico e densidade a granel superiores, quando comparado aos demais resíduos e menores teores de cinza. O poder calorífico do carvão do endocarpo foi superior, enquanto que os teores de materiais voláteis do carvão do epicarpo apresentaram os maiores resultados. Todos os resíduos avaliados do processamento do fruto da macaúba têm potencial na geração de energia, especialmente o endocarpo e o epicarpo. O carvão do endocarpo possui características adequadas para sua utilização como fonte de energia e como redutor. Palavras-chave: Acrocomia aculeata; bioenergia; macaúba. ABSTRACTThe use of biomass for energy purposes has been highlighted in as a way to reduce dependence on nonrenewable energy sources. Macaw palm, Acrocomia aculeata (Jacq.) Lodd. ex Martius, is an arborescent palm and has a high energy potential from the fruit processing. The aim of this study was to characterize the macaw palm residues after the fruit processing to evaluate its use "in natura" and as charcoal. The endocarp showed higher fixed carbon content, heating value and bulk density compared with other residues and lower ashes content. The heating value of endocarp charcoal was the highest, whereas the volatile matter levels of epicarp charcoal showed higher results. All evaluated residues from the macaw palm fruit processing have potential in power generation, especially the endocarp and the epicarp. The endocarp charcoal has suitable characteristics as source of energy and as a reductant.
Resumo -O objetivo deste trabalho foi comparar três métodos alternativos de determinação do teor de umidade da madeira em tora com o método preconizado pela ABNT. O teor de umidade da madeira foi determinado em uma amostra de serragem e com um medidor elétrico capacitivo. Além disso, o teor de umidade foi determinado pelo método da ABNT em amostras de madeira. Concluiu-se, portanto, que é viável a utilização de métodos alternativos para a determinação da umidade da madeira em toras, em substituição ao método tradicional, desde que se façam ajustes.
New technologies and emissions controls have been developed for the production of charcoal, but are not widely used in the industry. The present study seeks to evaluate the potential environmental impact of these new technologies as compared to traditional ones. A Life Cycle Assessment (LCA) of Brazilian charcoal produced with different technologies without and with the combustion of the gases in burners or furnaces was carried out. The inclusion of furnaces for the combustion of gases reduces all categories of potential environmental impacts by approximately 90% in both a circular masonry kiln and a rectangular masonry kiln with gas combustion. In the process of producing charcoal (gate-to-gate system boundary), in terms of climate change, the rectangular masonry kiln with gas combustion was approximately 63% less impactful than the circular masonry kiln with gas combustion. In the gate-to-gate analysis, the rectangular masonry kiln with gas combustion presented the best performance when not considering NO 2 and SO 2 . Considering these emissions, there were changes in the impact categories of particulate matter emission and terrestrial acidification, and the circular masonry kiln with gas combustion presented better performance (for cradle-to-gate system boundary). The process in a rectangular masonry kiln without gas combustion presented a greater contribution to the categories of terrestrial impact ecotoxicity (98%), due to the emission of acetic acid especially.
RESUMO O objetivo deste trabalho foi estudar a influência do diâmetro da madeira de eucalipto na produtividade e nas propriedades do carvão vegetal. A carbonização foi realizada em forno circular de alvenaria com capacidade volumétrica de 12 st, acoplado a uma fornalha para combustão dos gases. Foi analisada a madeira de Eucalyptus sp., em duas classes de diâmetro, de 7-12 cm e 13-18 cm. Para a determinação das propriedades do carvão vegetal foram coletadas amostras em três posições equidistantes do forno, com distância de 1 metro entre os pontos de coleta, considerando o no sentido da porta para fundo do forno. As carbonizações realizadas com madeira de menor diâmetro apresentaram redução de 14,86% do tempo de carbonização. O rendimento gravimétrico em carvão vegetal para as classes de menor e maior diâmetro foram de 33,62% e 31,67%, respectivamente. Os valores obtidos para análise química imediata do carvão para ambas as classes estão de acordo com o desejável para uso siderúrgico. Os valores de friabilidade para ambas as classes foram classificados como pouco friáveis. Entretanto, o carvão produzido com madeira de menor diâmetro teve menor percentual de geração de finos. A carbonização utilizando madeira de menor diâmetro apresentou maior produtividade em carvão vegetal. Palavras-chave: rendimento gravimétrico; tempo de carbonização; friabilidade.
The charcoal production when performed in woods with high moisture content negatively impacts the pyrolysis and causes an increase of greenhouse emissions. The aim of this study was to investigate the effects of moisture on the production and quality of charcoal for the pig iron industry. The slow pyrolysis of Eucalyptus sp. was carried out in four different wood moistures, 0, 20, 40 and 60% (dry base). The charcoal and gas yield decreased according to the increase of wood moisture. On the other hand, the bio-oil yield and charcoal friability increased along with the moisture content. The proximate analysis, bulk density and higher heating value of the charcoal were not influenced by the moisture content. The use of wood with moisture content below 20% in the production of charcoal is an alternative to improve productivity, contributing for the economic sustanainability of this sector.
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