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Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Orange peels (Citrus sinensis) are an abundant lignocellulosic residue that can be used as a carbon source to obtain solids with catalytic potential in the transformation of terpenes and their oxides into value-added products. This research seeks to evaluate the isomerization of a-pinene epoxide to campholenic aldehyde using a catalyst obtained from orange peels. The material OAC-Zn was obtained by activation of orange peel with ZnSO4.7H2O followed by thermal treatment at 500 °C; an additional solid was obtained from orange peel by pyrolysis at 500 °C (OC-500). XRD revealed the presence of ZnO and ZnS in OAC-Zn; TGA analysis indicated thermal stability in OAC-Zn and OC-500 materials; SEM images showed porous surfaces of different morphology, and the presence of microporosity in OC-500 and mesoporosity in the OAC-Zn that was confirmed by physical nitrogen adsorption. The elements C, O, Zn and S were identified in OAC-Zn by EDX analysis. The results of TPD-NH3 showed that the solids contained medium and weak acidity. Campholenic aldehyde was synthesized with a 96 % selectivity over the material OAC-Zn. [ABSTRACT FROM AUTHOR]

Copyright of Comunicaçõe Geológicas is the property of Laboratorio Nacional de Energia e Geologia, I.P. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Comunicaçõe Geológicas is the property of Laboratorio Nacional de Energia e Geologia, I.P. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O objetivo deste trabalho foi verificar a qualidade do ar no município de Charqueadas, localizado na Região Metropolitana de Porto Alegre, através dos dados de rotina de duas estações de monitoramento ambiental operadas pela Tractebel Energia, uma na cidade de Charqueadas e outra no município de Triunfo. Os resultados de partículas totais em suspensão (PTS) e partículas inaláveis (PM10) foram comparados com a Resolução CONAMA 03/1990 e a partir de amostras de material particulado total, foram realizadas análises de espectroscopia atômica e espectroscopia dispersiva de raio –X para identificar os elementos presentes no ar ambiente e sua relação com as principais fontes de emissão da região. As análises mostraram que a qualidade do ar observada na Estação localizada em Triunfo é melhor do que a observada na Estação de Charqueadas. Os dados obtidos indicam que há um reflexo positivo na qualidade do ar relacionado a implantação das tecnologias que reduziram as emissões de poluentes para a atmosfera. A análise das amostras revelou a presença de partículas de origem natural e antropogênica, entre os elementos analisados, os de maior concentração foram Fe e Mn nos dois locais avaliados, embora outros elementos químicos característicos de áreas urbanas industriais também tenham sido identificados. Com relação a caracterização morfológica das partículas de PTS as imagens obtidas mostram a presença de partículas heterogêneas com diferentes formas e tamanhos, os elementos predominantes foram o silício e o alumínio, no caso do silício está presente na composição dos filtros de fibra de vidro utilizados na amostragem

A Revista Lancet Countdown: Acompanhando o Progresso em Saúde e Mudanças Climáticas é uma colaboração internacional multidisciplinar que objetiva monitorar as relações entre saúde pública e mudanças climáticas. Reúne 35 instituições acadêmicas e agências das Nações Unidas de todos os continentes, embasando-se na expertise de climatologistas, engenheiros, economistas, cientistas políticos, profissionais de saúde pública e médicos. Todos os anos, a Lancet Countdown publica uma avaliação anual do estado das mudanças climáticas e da saúde humana, procurando oferecer aos tomadores de decisão acesso a orientações para uma política baseada em evidência de alta qualidade.

Firewood as humankind's most used fuel, was replaced by coal from XIII century on due to a number of factors. Thus coal became Second Industrial Revolution driving energy after the invention of the thermal machine in XVIII century. This text addresses the various technological, social, economic and environmental aspects that influenced this process, which culminated in the adoption of fossil fuel as the most consumed energy in the last two hundred years. [ABSTRACT FROM AUTHOR]

Rhodamine B dye has been widely used in the dyeing of semiprecious stones (agate), which are exported to many countries around the world, and in this dyeing process, colored effluents are generated. The main goal of this work was to use commercial active coal for the removal of rhodamine B. The adsorption studies were carried out to evaluate the effects of the coal mass, the pH of the dye solution and the adsorption kinetics. The results showed that for the initial dye concentration of 100 mg.L-1, the mass of coal with the highest adsorption capacity (73.72 ± 1.35 mg.g-1) was 0.1 g, when dye solution showed pH 8, the highest adsorption capacity (79.38 ± 0.33 mg.g-1) was observed. It was also observed that after 75 minutes the equilibrium was reached being the pseudo-second order model, which best represented the experimental data, in which R² and R²ajst were above 0.97 and EMR were down 3.9%. Thus the activated carbon tested showed a good adsorbent for removal of the rhodamine dyeing companies agate dyeing. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Ciencias Economicas: Investigacion y Reflexion is the property of Revista Facultad de Ciencias Economicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acid drainage influence on the water and sediment quality was investigated in a coal mining area (southern Brazil). Mine drainage showed pH between 3.2 and 4.6 and elevated concentrations of sulfate, As and metals, of which, Fe, Mn and Zn exceeded the limits for the emission of effluents stated in the Brazilian legislation. Arsenic also exceeded the limit, but only slightly. Groundwater monitoring wells from active mines and tailings piles showed pH interval and chemical concentrations similar to those of mine drainage. However, the river and ground water samples of municipal public water supplies revealed a pH range from 7.2 to 7.5 and low chemical concentrations, although Cd concentration slightly exceeded the limit adopted by Brazilian legislation for groundwater. In general, surface waters showed large pH range (6 to 10.8), and changes caused by acid drainage in the chemical composition of these waters were not very significant. Locally, acid drainage seemed to have dissolved carbonate rocks present in the local stratigraphic sequence, attenuating the dispersion of metals and As. Stream sediments presented anomalies of these elements, which were strongly dependent on the proximity of tailings piles and abandoned mines. We found that precipitation processes in sediments and the dilution of dissolved phases were responsible for the attenuation of the concentrations of the metals and As in the acid drainage and river water mixing zone. In general, a larger influence of mining activities on the chemical composition of the surface waters and sediments was observed when enrichment factors in relation to regional background levels were used.

O presente texto debruça-se sobre o relatório produzido por Ernest Fleury (1878‑1958), professor do Instituto Superior Técnico, na sequência de visita efetuada em abril de 1923, a convite da concessionária, aos barreiros e pedreiras existentes, respetivamente, entre Buarcos e Tavarede e no perímetro do Couto Mineiro do Cabo Mondego (Figueira da Foz). Estas explorações alimentavam as fábricas de cerâmica, cal hidráulica e cimento locais, daí resultando produtos emblemáticos que granjeavam bom acolhimento no mercado nacional, mas que enfrentavam uma competição séria e crescente. O relatório descreve as principais características dos depósitos em exploração e pronuncia-se sobre as potencialidades destes jazigos, no âmbito de uma longa colaboração que este importante geólogo teve com as indústrias do Cabo Mondego. Neste âmbito, para além da sua aura técnica, este documento deve ler-se num contexto temporal e como um contributo para a história da Geologia Aplicada em Portugal, de que Fleury foi pioneiro. https://doi.org/10.14195/1645-2259_16_15

Taking into account the importance of the effect on the health of PM10 inhalable particles and the metals associated with them, the levels of metals were assessed: Al, Cr, V, As, Se, Na, K, Mg, Ca, Bi, Fe, Hg and Pb, generated by natural sources such as marine aerosol and re-suspension of the soil and anthropogenic sources such as coal mining and vehicular circulation, in Fonseca, La Guajira, Colombia, samples were collected at two sites near the carboniferous complex, during drought and rainfall periods, using a high volume sampler with quartz fiber filters, with a monthly frequency for a total of 20. The samples were subjected to a process of acid digestion, and analyzed by mass spectrometry with inductively coupled Plasma (ICP-MS). The reported PM10 levels exceeded the WHO-established 20 µg/m³ annual standard. The most concentrated metals correspond to Na (2.4 µg/m³ 1.49 µg/m³), Al (0.52 µg/m³ 1.78 µg/m³), Ca (0.49 µg/m³ 0.60 µg/m³) and Cr (0.40 Mg/m³ 0.18 µg/m³). There were no statistically significant differences between the sampling sites. V, Hg and Pb did not exceed the air quality standard established for Colombia and who; As such, the As has largely exceeded the permissible limit of Colombia and OMS. In addition, the statistical analysis allows to conclude that metals can come from the same source, both natural and anthropogenic. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pela importância econômica da madeira de algumas espécies do gênero Mimosa L. ocorrentes na caatinga nordestina e pelo fato de Mimosa ophthalmocentra Mart. ex Benth. (jurema-de-imbira), às vezes, ser confundida com Mimosa tenuiflora (Willd.) Poir. (jurema-preta) ou vice-versa, este trabalho objetivou apresentar novos dados referentes à anatomia e densidade básica da madeira das duas espécies, visando oferecer subsídio para identificação das duas espécies, identificar caracteres anatômicos da madeira relacionando-os com o ambiente caatinga e apresentar o potencial energético que sua madeira possui. O estudo anatômico e a determinação da densidade da madeira foram realizados com amostras ao nível do peito (1,30 m acima do solo) e em dois galhos com diferentes diâmetros, de espécimes ocorrentes nos municípios de Serra Talhada e Sertânia, Pernambuco, Brasil. As espécies apresentam distinção expressa através do tipo de casca, coloração do cerne e do alburno, além das características peculiares da madeira. Mimosa ophthalmocentra apresenta camadas de crescimento distintas, constituídas por linhas de parênquima axial contendo cristais, parênquima axial escasso e menor quantidade de raios por mm². Já Mimosa tenuiflora apresenta camadas de crescimento distintas, porém sem cristais, parênquima axial vasicêntrico, em faixas ou aliforme confluente, e maior percentagem de raios. Ambas apresentam algumas estruturas da madeira com as características anatômicas comuns às diversas espécies do gênero Mimosa, contribuindo assim para uma melhor caracterização do gênero. Pelos parâmetros anatômicos da madeira e pela elevada densidade básica (>0,84 g/cm³), concluiu-se que as duas espécies apresentam perspectivas seguras para a produção de álcool combustível e carvão vegetal desde a fase de lenho juvenil. Mimosa ophthalmocentra apresenta maior potencial energético, pela maior percentagem de fibras e por possuir parênquima escasso e menor percentagem de raios.Due to the economic importance of the wood of Mimosa L. species in Northeastern Brazil's caatinga and to the fact that Mimosa ophtalmocentra Mart. ex Benth. ("jurema-de-imbira") is confused with Mimosa tenuiflora (Willd.) Poir. ("jurema-preta") and vice versa, this research aimed to present new data related to the anatomy and basic density of the wood of both species; to contribute to the taxonomic study for differentiating them; to identify anatomical characters of the wood relating them to the caatinga environment; and to present the energetic potential that they possess. The anatomical study and wood density determination were carried out with samples at dbh level and with two branches of individuals within the municipalities of Serra Talhada and Sertânia (Pernambuco). The species both differed in bark type, color of heartwood and sapwood, besides the different anatomical characteristics found in the wood. Mimosa ophtalmocentra has distinct growth layers consisting of parenchyma lines containing crystals, scarce parenchyma and smaller quantity of rays. Mimosa tenuiflora, on the other hand, also has growth layers, but without crystals, axial parenchyma vasicentric, confluent and in bands, and greater percentage of rays. Both species have some wood elements with anatomical characteristics typical of representatives of Mimosa, contributing therefore to a better taxonomic understanding of the genus. Based on wood anatomical parameters and elevated basic density (> 0.84 g/cm³), the conclusion was reached that both species have great perspectives for the production of fuel alcohol and charcoal since juvenile wood age. Because Mimosa ophthalmocentra has scarce parenchyma and fewer rays, it shows greater energetic potential than Mimosa tenuiflora.

n este artículo se presenta una descripción de la relación existente entre el pensamiento económico y los recursos naturales, en especial, los no renovables. Se define el modelo de Hotelling, con su planteamiento matemático y su respectiva solución gráfica, el cual permite determinar el sendero óptimo de agotamiento de un recurso natural no renovable y una estimación de su precio de mercado. Un marco general sobre la actualidad y perspectivas del carbón térmico colombiano es la base para la aplicación de este modelo a dicho recurso energético, lo que determina, con base en las reservas probadas de carbón térmico en Colombia y su función de demanda, el tiempo de agotamiento y su precio de comercialización.Neste artigo apresenta-se uma descrição da relacão existente entre o pensamento económico e os recursos naturais, especialmente, os não renováveis. Define-se o modelo de Hotelling, com a sua proposta matemática e a sua respetiva solução gráfica, o qual permite determinar o caminho ótimo de esgotamento de um recurso natural não renovável e uma estimativa do seu preço de mercado. Um enquadramento geral sobre a atualidade e perspectivas do carvão térmico colombiano é a base para a aplicação do este modelo a dito recurso energético, o que determina, com base nas reservas provadas de carvão térmico em Colômbia e sua função de demanda, o tempo de esgotamento e o seu preço de comercialização.In this paper a description of the relationship between economic thought and natural resources, especially those non-renewable, is presented. The Hotelling model is defined, with its mathematical approach and the respective graphical solution, which determines the optimal path of depletion of a non-renewable natural resource and an estimation of its market price. A general frame for the present situation and prospects for thermal coal in Colombia is the basis for the implementation of this model to this energy resource. Based on the proven reserves of thermal coal in Colombia and its demand function, time depletion and its trading price are determined.

O desenvolvimento vegetativo e de raízes de espécies das orquídeas brasileiras Cattleya intermedia (John Lindley) e Miltonia clowesii (John Lindley) utilizando diferentes substratos e extrato pirolenhoso foi avaliado. Mudas produzidas in vitro foram transferidas para recipientes com: T1 – casca de pinus (Pi), fibra de coco (Co) e casca de arroz carbonizada (Ca); T2 – PiCoCa e carvão vegetal (Car); T3 – PiCoCaCar, sendo o carvão vegetal tratado com extrato pirolenhoso (EP); T4 – CoCaCarEP; e T5 – CoCaCar. Todos os materiais foram utilizados na mesma proporção. Altura da parte aérea, número de raízes, comprimento da maior raiz, número de brotos, massa fresca total e pH foram avaliados sete meses após a instalação do experimento. Para C. intermedia, o T3 foi superior aos outros tratamentos, com valores maiores para os parâmetros estudados. O T4 e, a seguir, o T2 foram os tratamentos nos quais os valores mais seaproximaram do melhor tratamento. Para Milt. clowesii, a mesma tendência se verificou, entretanto sem a mesma magnitude nas diferenças entre os tratamentos. De maneira geral, o extrato pirolenhoso incrementou o desenvolvimento vegetativo e radicular das orquídeas estudadas.The vegetative and root development of the species of Brazilian orchids Cattleya intermedia (John Lindley) and Miltonia clowesii (John Lindley) using different substrates and pyroligneous extract were assessed. Seedlings from in vitro propagation were transferred to vessels with: T1 - Pinus bark (Pi), coconut fibers (Co) and charred peel of rice (Cr); T2 – PiCoCr and vegetal charcoal (Ch), T3 – PiCoCrCh with the charcoal treated with pyroligneous extract (PE);T4 - CoCrChEP and T5 - CoCrCh. The materials used in substrates were placed in the same ratio. Plant height, number of roots, length of the greater root, number of buddings, total fresh mass and pH were assessed seven months after experiment onset. For Para C. intermedia, T3 was superior than the other treatments, with higher values for the studied parameters. T4, followed by T2, were the treatments in which the values were closer to the best treatment. For Milt. clowesii the same tendency was found, although without the same magnitude in the differences among treatments. In general, pyroligneous extract incremented the vegetative and root development of the studied orchids.

Com o objetivo de analisar a fertilidade de solos construídos sobre áreas mineradas de carvão a céu aberto (28º35'50'' S e 49º25'26'' W) no Município de Siderópolis, SC, foram escolhidas duas áreas recuperadas em épocas distintas: área IV em 2002 e área VI em 2003. No centro de cada área foi estabelecida uma transecção de 100 m de comprimento, em que foram lançadas alternadamente à direita e à esquerda, a intervalos de 10 m, transecções perpendiculares de 20 m, em que foram coletadas nove amostras de solo (0 - 0,2 m). As nove amostras de cada grupo de dois transectos consecutivos foram reunidas em uma amostra composta, reduzindo o universo amostral de 90 para cinco amostras de solo de cada área. Foram analisados os teores de argila, pH, fósforo, potássio, matéria orgânica, alumínio, cálcio, magnésio, H + Al, soma das bases, CTC e saturação por bases. Em ambas as áreas, o teor de argila foi enquadrada na classe 3, o teor de matéria orgânica foi baixa, o pH e V% muito baixos, o Mg variou de médio a alto, a SB variou de baixa a média e a CTC foi considerada alta. Na área IV, o teor de P foi baixo, e o de Ca variou de médio a baixo, enquanto na área VI o teor de P variou de baixo a médio, e o de Ca foi baixo. Embora tenham sido observadas diferenças entre alguns dos parâmetros analisados, essas não foram severamente afetadas pelo tempo de recuperação das duas áreas.With the objective of analyzing the fertility of soils built over open pit coal mining areas (28º35'50'' S e 49º25'26'' W) in the city of Siderópolis (SC), two areas of different reclamation ages were selected: area IV and area VI, reclaimed in 2002 and 2003, respectively. A 100m transection was established in the center of each area, where perpendicular 20m transects were tossed at regular intervals of 10m, alternating to the right and to the left, and nine soil samples were collected (0 - 0,2 m). The nine samples of each group of two consecutive transects were gathered into a compound sample, reducing the sampling universe from 90 to 5 samples of soil for each area. The contents of clay, pH, Phosphorus, Potassium, organic matter, Aluminum, Calcium, Manganese, H + Al, base sum, CTC and base saturation were analyzed. In both areas, the content of clay fell into class three category, the content of organic compound was low, the pH and V% significantly low. Manganese varied from medium to high, BS varied from low to medium and CTC was considered high. In area IV, the content of P was low and Ca varied from medium to low, while in area VI the content of P varied from low to medium and Ca was low. Although differences had been observed among some of the parameters analyzed, they were not severely affected by the reclaimed time of the two areas.

Este trabalho objetivou estudar a anatomia e a densidade básica da madeira de Caesalpinia pyramidalis utilizada pelas comunidades locais, ocorrente na caatinga de Pernambuco, nos municípios de Serra Talhada e Sertânia, assim como comparar a percentagem dos elementos do lenho no tronco e nos galhos, na própria árvore, a fim de estabelecer o potencial total do lenho para produção de energia. As amostras do lenho do tronco (DAP) e de ramos de seis árvores da espécie foram coletadas nos dois municípios acima citados, em 2002. As análises das amostras seguiram os métodos usualmente empregados em estudo de anatomia de madeiras. Pelos parâmetros anatômicos do lenho e a elevada densidade básica (>0,84 g/cm³), concluiu-se que Caesalpinia pyramidalis revela grande quantidade de celulose e lignina, portanto apresentou perspectivas seguras para produção de álcool combustível e carvão vegetal. Pode-se propor o uso do lenho do tronco e dos galhos como combustível, desde a fase jovem da madeira, pela grande concentração de fibras, menor concentração de vasos e menor quantidade de parênquima, nos espécimes dos dois municípios.This work aimed to study the anatomy and basic density of Caesalpinia pyramidalis wood, used by local populations in the municipalities of Serra Talhada and Sertânia (Pernambuco), to assess the percentage of wood elements in the trunk and branches in both localities, and in the tree itself, in order to establish total wood potential for energy production. Samples of the trunk (dbh) and of branches from six trees of the species were collected in 2002. Sample analysis followed the usual methods of wood anatomy studies. Based on the anatomical parameters of the trunk and the high basic density (>0.84 g/cm³), we conclude that Caesalpinia pyramidalis wood contains an enormous amount of cellulose and lignin. Due to these features, this species showed good perspectives for the production of alcohol and charcoal. The trunk and branches can be used for fuel even at the immature stage because of high fiber concentration, low vessel concentration and low amount of parenchyma at this stage in both municipalities.

Neste trabalho, apresenta-se um novo material adsorvente, obtido a partir da pirólise de resíduos da erva-mate. O carvão resultante demonstrou elevada área superficial específica quando comparado com outros materiais pirolisados e elevada capacidade de remoção de contaminantes orgânicos de soluções aquosas. Os valores de área específica apresentados pelos materiais foram de 344, 191 e ~0,5 m² g-1, para o carvão Mate 1, Mate 2 e Mate 3, respectivamente. As isotermas de adsorção mostraram que os carvões apresentam potencial para utilização como adsorvente para compostos orgânicos, tais como: o corante têxtil vermelho reativo, o corante azul de metileno e para o herbicida atrazina, sendo que os máximos de adsorção utilizando o carvão Mate 1 foram de 16, 230 e 30 mg g-1, respectivamente.In this work we present a new adsorbent material, obtained by maté waste pyrolisis. The resulting charcoal presented high specific area when compared with other pyrolized materials and also high capacity to remove organic contaminants from aqueous solution. The charcoal showed specific area of 344, 191 and ~0.3 m² g-1 for sample Mate 1, Mate 2 and Mate 3, respectively. According to the corresponding adsorption isotherm these materials present good adsorption capacity for reactive textile and methylene blue dyes and the herbicide atrazine. Adsorption maxima were respectively 16, 230 and 35 mg g-1 for such substances, when sample Mate 1 was used.

Copyright of Revista de Historía da Sociedade e da Cultura is the property of Revista de Historia da Sociedade e da Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este estudo foi realizado em casa de vegetação, no ano de 1997, na Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul (UFRGS). Em um desenho experimental de blocos casualizados com parcelas divididas e seis repetições, foram avaliadas as seguintes variáveis: comprimento das raízes, raio médio, superfície ocupada e matéria seca produzida pelas raízes do azevém, visando avaliar o efeito da adição de substâncias húmicas no desenvolvimento das raízes do azevém. As plantas foram cultivadas em areia irrigada, com uma solução nutritiva completa e quatro doses de substâncias húmicas (0, 10, 20 e 30-mg/litro), extraídas a partir dos carvões das minas do Capané (Palermo CE-4.200 e Palermo CE-4.700), Leão (Leão CE-5.200) e Candiota (Candiota Camada Superior, Candiota Camada Inferior, Candiota CE-3.300 e Candiota CE-4.700). Para todas as variáveis analisadas a análise estatística acusou significância para os efeitos da interação doses x matéria-prima. Os resultados demonstraram que as substâncias húmicas promoveram o desenvolvimento das raízes aumentando: a) em 100,87% o comprimento da raiz; b) em 49,23% o peso das raízes e c) em 68% a superfície ocupada pelas raízes. Conclui-se que as substâncias húmicas promoveram o desenvolvimento das raízes do azevém e as distintas fontes destas substâncias agiram de forma diferente sobre os parâmetros das quatro variáveis analisadas.

Copyright of Revista Medicina is the property of Revista Medicina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O desenvolvimento vegetativo e de raízes de espécies das orquídeas brasileiras Cattleya intermédia (John Lindley) e Miltonia clowesii (John Lindley) utilizando diferentes substratos e extrato pirolenhoso foi avaliado. Mudas produzidas in vitro foram transferidas para recipientes com: T1 – casca de pinus (Pi), fibra de coco (Co) e casca de arroz carbonizada (Ca); T2 – PiCoCa e carvão vegetal (Car); T3 – PiCoCaCar, sendo o carvão vegetal tratado com extrato pirolenhoso (EP); T4 – CoCaCarEP; e T5 – CoCaCar. Todos os materiais foram utilizados na mesma proporção. Altura da parte aérea, número de raízes, comprimento da maior raiz, número de brotos, massa fresca total e pH foram avaliados sete meses após a instalação do experimento. Para C. intermédia, o T3 foi superior aos outros tratamentos, com valores maiores para os parâmetros estudados. O T4 e, a seguir, o T2 foram os tratamentos nos quais os valores mais se aproximaram do melhor tratamento. Para Milt. Clowesii, a mesma tendência se verificou, entretanto sem a mesma magnitude nas diferenças entre os tratamentos. De maneira geral, o extrato pirolenhoso incrementou o desenvolvimento vegetativo e radicular das orquídeas estudadas.

The goal of the research is to analyze the relationships (re) produced by capital appropriation process and nature of work in charcoal production in the municipality of Cândido Sales - BA, from the on-site observation of the productive activity of the charcoal. In order to take account of the dynamics that constructs the reality of the business of charcoal, the method historical-dialectical-materialist assumption is the theoretical, methodological and political development assumed in the study. The indiscriminate exploitation of nature and the exploitation of workers in coal plants are the objective reflection of the reduction to exchange values of society-nature relationship subjugated to (dis) mands of capital which (re) produces the territory for the appropriation of nature and concrete work, oxygenating the fire and smoke burning forests and the hope of the working class in charcoal. [ABSTRACT FROM AUTHOR]

Some aspects of permeability deterioration in blast furnace process at high rates of pulverized coal injection are not well known yet. At operational practice variations in the ash quality of injected coals can affect the furnace performance. Previous work has investigated the behavior of individual coals ash at high temperatures in relation to the chemical and mineralogical compositions. This work aimed to assess this behavior for coal blends. Four coals and seven blends were selected and ashed at 800-850°C. The samples were analyzed by X-ray fluorescence and X-ray diffraction techniques and ASTM ash fusion (AFT) and viscosity tests were performed. Ash containing high contents of Si and Al showed higher fusion temperatures and higher viscosity at 1500°C, due mainly to the higher content of Mullite and to the low basicity, while those presenting significant contents of Fe, Ca and S had lower fusion temperatures and lower viscosity, due to the higher content of Anorthite and/or to the higher basicity. [ABSTRACT FROM AUTHOR]

The synthesis of zeolitic phases from mullite, the main component of fly ash generated during burning coal, hasbeen investigated. Thermodynamic analysis is performed in order to assess required temperatures and concentrations for the synthesis, as well as to determine the thermodynamically more stable species. X-Ray Diffraction (XRD) analysess how different zeolitic phases to be crystallized as product of the hydrothermal processing. The thermodynamic valuescalculated in this study proved similar to the experimental results and of other authors, and enabled the definition of the regions of stability for the species in the reactional environment. The experimental results, combined with the analysis of these diagrams, show that the stability of species to be formed during the hydrothermal treatment of coal ash are strongly dependent on temperature and NaOH concentration. The increase of both factors, however, drives the reaction towards less noble products, particularly hydroxycancrinite. [ABSTRACT FROM AUTHOR]

The use of international standards for the classification of Southern Brazilian coal has shown wide variation in the determination of the real coal rank. The Economic Commission for Europe (ECE UN) has developed standard criteria for coal classification, based on the simultaneous consideration of its three main characteristics: composition, rank and grade. Supplementary analyses are also required. Samples from the main coal seam exploited in Leão, located in Rio Grande do Sul, Southeast Paraná Basin, were subjected to petrographic, proximate, bed moisture and calorific value determination, in order to be classified according to the UN ECE rules. The coal seams occur in the Rio Bonito, Permian (Artinskian-Kungurian) of the Paraná Basin. According to the International Classification (ECE-UN) the in-seam coals at Leão are in the parabetuminous coal range (or medium-rank coal D). The results were also compared with data from earlier studies focusing on aspects of coal rank. [ABSTRACT FROM AUTHOR]

This study investigates geophysical logging as a tool to predict coal quality. Some of the coal's chemical parameters were determined by laboratory analysis and were compared against values derived from geophysical logging correlation (natural gamma radiation and resistivity versus ash content, specifically). The results showed a strong correlation between the coal's natural gamma emissions and their ash content. From this correlation, a simple linear model was obtained and used to estimate ash grades, directly from geophysical logging records. The error of these predictions is less than ± 5%. Additionally, results showed no correlation between the sulphur grade, or volatile matter, and the geophysical records. Ash grades derived from natural gamma ray values can be usedas secondary information to evaluate coal quality during resource estimation, when combined with lab analysis and appropriate geostatiscal methods. The methodology is illustrated by means of a case study at a coal deposit located in southern Brazil. [ABSTRACT FROM AUTHOR]

In the room-and-pillar mining method, conventional mining system had its peak along the 1950's and 1960's in the United States, giving place to the continuous mining system. In Brazil, these systems are still in use in some underground coal mines. This paper presents a production simulator developed to emulate the mining cycle at Carbonífera Metropolitana S.A., where all the unit operations in coal mining were included. A model was proposed for the room-and-pillar mining system, aiming to maximize the extraction at all coal faces from a given panel. The technique used was discrete-event simulation. After constructed and validated, the simulator proved to be efficient to forecast daily ROM production. Added to this, the simulator is able to help in visualizing bottlenecks and operations delays in the mining cycle. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the carbon dioxide (CO2) emissions from coal combustion in Brazil. A methodology using the emission factors estimated specifically for Brazilian coals is proposed. The use of secondary fuels and the electricity produced by the power plants were also considered in the calculations. The results obtained indicated carbon emissions of 1,794 Gg year-1 for 2002. In some cases 20% lower emissions were observed in comparison to the official methodology (MCT) that does not consider coal moisture and uses generic emission coefficients not adapted for Brazilian coal. The results suggest that national inventories must be revised and combustion systems should be updated in order to increase effi ciency and to reduce CO2 emissions as a sustainable measure for the coal use in the country. [ABSTRACT FROM AUTHOR]

Substratum and pyroligneous extract in the cultivation of Brazilian orchids Cattleya intermedia (John Lindlcy) and Miltonia clowali (John Lindley) (Orchidaceae). The vegetative and root development of the species of Brazilian orchids Cattleya intennedia (John Lindley) and Mitonia clowesli (John Lindky) using different substrates and pyroligneous extract were assessed. Seedlings from in citro propagation were transferred to vessels with: T1 - Pinus bark (Pi), coconut fibers (Co) and charred peel of rice (Cr): T2 - PiCoCr and vegetal charcoal (Ch). T3 - PiCoCrCh with the charcoal treated with pyroligneous extract (PE); T4 - CoCrChEP and T5 - CoCrCh. The materials used in substrates were placed in the same ratio. Plant height, number of roots, length of the greater root, number of buddings, total fresh mass and pH were assessed seven months after experiment onset. For Para C. intennedia, T3 was superior than the other treatments, with higher values for the studied parameters. T4, followed by T2, were the treatments in which the values were closer to the best treatment. For Milt. clowesii the same tendency was found, although without the same magnitude in the diffrences among treatments. In general, pyroligneous extract incremented the vegetative and root development oldie studied orchids. [ABSTRACT FROM AUTHOR]

A cidade de Criciúma até pouco tempo era visivelmente reconhecida como a capital brasileira do carvão. A exploração do chamado ouro negro provocou transformações significativas na pequena vila de agricultores erguida no final do século XIX. Este artigo tem a pretensão de contribuir para uma introdução ao debate sobre a cidade de Criciúma ao longo do século XX, especialmente em sua última década.

Atualmente, o CBM representa uma importante fonte de energia alternativa. A mais importante sucessão sedimentar portadora de carvão no Brasil ocorre na Bacia do Paraná, com as maiores reservas localizadas nas jazidas do RS e de SC. Este trabalho tem por objetivo analisar as características químicas e petrográficas das camadas de carvão de três poços, realizados recentemente na jazida Sul Catarinense (SC) nos municípios de Treviso e Araranguá, com o intuito de avaliar a capacidade de geração de gás metano associado. Foram coletadas amostras de sete camadas de carvão (Barro Branco, Irapuá, A, Bonito Superior, Bonito Inferior, Pré-Bonito Superior e Pré-Bonito Inferior) da Formação Rio Bonito que foram submetidas à análise petrográfica e química. O litotipo carvão fosco bandado (BD) predominou no CBM-SC-2012, e carvão fosco (D), no CBM-SC-2013. Os resultados petrográficos indicaram valores de 0,60 a 1,26 Rrandom (%), classificando o carvão segundo o rank desde betuminoso alto volátil C até betuminoso médio volátil. A análise de macerais mostra variação na composição das camadas, com predomínio de vitrinita e inertinita. Quanto à análise imediata, as amostras variaram de 34,93 a 65,70% em peso de cinza. O poder calorífico varia de 1858,0 a 5074,8 cal/g. O conteúdo de carbono varia de 4,15 a 65,81%, e o enxofre, de 0,22 a 12,43%. De acordo com os parâmetros analisados, as camadas Barro Branco e Irapuá apresentam as condições necessárias para geração e armazenagem de gás natural, enquanto a camada Bonito apresenta baixo potencial devido ao alto conteúdo de matéria mineral.

Resumo: O Brasil passou por um período de crise energética em 2000. Contudo, este país apresenta vastas reservas de carvão que poderiam ser mais exploradas. Depois da crise o consumo de carvão teve algum incremento, mais estudos deveriam ser feitos a fim de minimizar as emissões de SOx e o aproveitamento das cinzas. As propriedades das cinzas dependem das características dos minerais que as originaram e da temperatura de combustão. A maioria dos sistemas empregados para queima é de combustão em leito pulverizado (1200-1600°C) ou fluidizado (850°C - mais comum fora do Brasil). Este artigo apresenta um estudo preliminar das características físicas do carvão, como tamanho e superfície, submetida a diferentes temperaturas com a finalidade de compreender seu comportamento nestas condições. A reconstrução mineralógica do carvão também foi desenvolvida.