999 resultados para Green, Mildred Browning


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The treatment efficiency of laboratory wastewaters was evaluated and ecotoxicity tests with Chlorella vulgaris were performed on them to assess the safety of their environmental discharge. For chemical oxygen demand wastewaters, chromium (VI), mercury (II) and silver were efficiently removedby chemical treatments.Areduction of ecotoxicitywas achieved; nevertheless, an EC50 (effective concentration that causes a 50% inhibition in the algae growth) of 1.5% (v/v) indicated still high level of ecotoxicity. For chloride determination wastewaters, an efficient reduction of chromium and silver was achieved after treatment. Regarding the reduction of ecotoxicity observed, EC50 increased from 0.059% to 0.5%, only a 0.02% concentration in the aquatic environment would guarantee no effects. Wastewaters containing phenanthroline/iron (II) complex were treated by chemical oxidation. Treatmentwas satisfactory concerning chemical parameters, although an increase in ecotoxicitywas observed (EC50 reduced from 0.31% to 0.21%). The wastes from the kinetic study of persulphate and iodide reaction were treated with sodium bisulphite until colour was removed. Although they did not reveal significant ecotoxicity, only over 1% of the untreated waste produced observable effects over algae. Therefore, ecotoxicity tests could be considered a useful tool not only in laboratory effluents treatment, as shown, but also in hazardous wastewaters management.

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Zero-valent iron nanoparticles (nZVIs) are often used in environmental remediation. Their high surface area that is associated with their high reactivity makes them an excellent agent capable of transforming/degrading contaminants in soils and waters. Due to the recent development of green methods for the production of nZVIs, the use of this material became even more attractive. However, the knowledge of its capacity to degrade distinct types of contaminants is still scarce. The present work describes the study of the application of green nZVIs to the remediation of soils contaminated with a common anti-inflammatory drug, ibuprofen. The main objectives of this work were to produce nZVIs using extracts of grape marc, black tea and vine leaves, to verify the degradation of ibuprofen in aqueous solutions by the nZVIs, to study the remediation process of a sandy soil contaminated with ibuprofen using the nZVIs, and to compare the experiments with other common chemical oxidants. The produced nZVIs had nanometric sizes and were able to degrade ibuprofen (54 to 66% of the initial amount) in aqueous solutions. Similar remediation efficiencies were obtained in sandy soils. In this case the remediation could be enhanced (achieving degradation efficiencies above 95%) through the complementation of the process with a catalyzed nZVI Fenton-like reaction. These results indicate that this remediation technology represents a good alternative to traditional and more aggressive technologies.

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The effect of boiling (10 minutes) on eleven green vegetables frequently consumed in the Mediterranean diet was evaluated. For that, some physicochemical parameters and the contents of vitamin C, phenolics and carotenoids, as well as the antioxidant activity, were determined in raw and boiled samples. The raw vegetables analysed in this study were good sources of vitamin C, carotenoids and phenolic compounds, with contents ranging from 10.6 to 255.1 mg/100 g, 0.03 to 3.29 mg/100 g and 202.9 to 1010.7 mg/100 g, respectively. Boiling promoted losses in different extensions considering both the different bioactive compounds and the distinct vegetables analysed. Contrary to phenolics (more resistant), vitamin C was the most affected compound. Boiling also originated significant losses in the antioxidant activity of the vegetables. Considering all the parameters analysed, the vegetables most affected by boiling were broccoli and lettuce. The least affected ones were collard and tronchuda cabbage.

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A new environmentally friendly Au nanoparticles (Au NPs) synthesis in glycerol by using ultraviolet irradiation and without extra-added stabilizers is described. The synthesis proposed in this work may impact on the non-polluting production of noble nanoparticles with simple chemicals normally found in standard laboratories. These Au NPs were used to modify a carbon paste electrode (CPE) without having to separate them from the reaction medium. This green electrode was used as an electrochemical sensor for the nitrite detection in water. At the optimum conditions the green sensor presented a linear response in the 2.0×10−7–1.5×10−5 M concentration range, a good detection sensitivity (0.268 A L mol−1), and a low detection limit of 2.0×10−7 M of nitrite. The proposed modified green CPE was used to determine nitrite in tap water samples.

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In the last decades nanotechnology has become increasingly important because it offers indisputable advantages to almost every area of expertise, including environmental remediation. In this area the synthesis of highly reactive nanomaterials (e.g. zero-valent iron nanoparticles, nZVI) is gaining the attention of the scientific community, service providers and other stakeholders. The synthesis of nZVI by the recently developed green bottom-up method is extremely promising. However, the lack of information about the characteristics of the synthetized particles hinders a wider and more extensive application. This work aims to evaluate the characteristics of nZVI synthesized through the green method using leaves from different trees. Considering the requirements of a product for environmental remediation the following characteristics were studied: size, shape, reactivity and agglomeration tendency. The mulberry and pomegranate leaf extracts produced the smallest nZVIs (5–10 nm), the peach, pear and vine leaf extracts produced the most reactive nZVIs while the ones produced with passion fruit, medlar and cherry extracts did not settle at high nZVI concentrations (931 and 266 ppm). Considering all tests, the nZVIs obtained from medlar and vine leaf extracts are the ones that could present better performances in the environmental remediation. The information gathered in this paper will be useful to choose the most appropriate leaf extracts and operational conditions for the application of the green nZVIs in environmental remediation.

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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

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UNL - NSBE

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The Zubarev equation of motion method has been applied to an anharmonic crystal of O( ,,4). All possible decoupling schemes have been interpreted in order to determine finite temperature expressions for the one phonon Green's function (and self energy) to 0()\4) for a crystal in which every atom is on a site of inversion symmetry. In order to provide a check of these results, the Helmholtz free energy expressions derived from the self energy expressions, have been shown to agree in the high temperature limit with the results obtained from the diagrammatic method. Expressions for the correlation functions that are related to the mean square displacement have been derived to 0(1\4) in the high temperature limit.

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The green movement has evolved over the last twenty years from various social, peace and ecology activist organizations into direct political participation in parliamentary institutions through the Green Party. Although there is no definable theory of green politics, the culmination of interacting social movements as well as feminist, decentralist and in many cases, left wing political ideology, has produced a specific kind of political direction for the Greens internationally. As a result of the increased a ttention and awareness given to ecological issues , combined with the heightened evidence of large scale environmental deterioration, public attitudes and government decisions on development and natural resource management have been significantly altered. The Green Party of Canada is still r elatively young in comparison to its European counterparts, although ecologica l awareness and interest in t he green movement in Canada is strong, as reflected not only in support on a political level for the Canadian Greens I but for environmental issues and a ctivism in general. For this reason it s important to determine whether or not the Green Party is a significant aspect of the Canadian green movement, and if in fact its representation is necessary as an active participant in the Canadian political system . The Green Party of Canada, as a vital aspect of the Canadian green movement, and its connection to international green organizations can be examined primarily through the examp l es of both the Canadian Greens and the Green party of Ontario , by using original party documents and literature, information gained through Green party meetings and discussions with members, and commentary by Green theorists where app licable. As well, the influence on the Canadian green movement by the German Green Party is outlined , again mainly through party literature, documents and critiques of the party's experiences. This study reveals several existing and potential problems fo r t he Green Party in Canada, and the political fut ure of the Canadian green movement in general. Some, such as the real i ties of the Canadian political system are external to the movement, and may be overcome with adjustments in goals and methods, and a realization of the changing attitude towards environmental issues in a political context . On the other hand, internal party disfunctions in both organization and direction, caused mainly by the indefinite parameters of green ideology, threaten to exploit the already problematic aspects evident in t he Green Party . Aside from its somewhat slow beginnings, the Green Party in Canada has developed into a strong grassroots social movement, not however from its political visibility but from the steady growth in the popul ari ty of ecological pol i t ics in Canada. Due to the seeming enormity of the obstacles facing the Greens in their effort 4 to achieve electoral success, it is doubtful that Parliamentary representation will be achieved without a major re-orientation of party organization and methods. UI timately the strength of the Green Party in Canada will be based upon its ability to survive as a significant movement, and its willingness to continue to challenge political thought and practice.

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The aggressive mushroom competitor, Trichoderma harzianum biotype Th4, produces volatile antifungal secondary metabolites both in culture and during the disease cycle in compost. Th4 cultures produced one such compound only when cultured in the presence of Agaricus bisporus mycelium or liquid medium made from compost colonised with A. bisporus. This compound has TLC and UVabsorption and characteristics indicating that it belongs to a class of pyrone antibiotics characterised from other T. harzianum biotypes. UV absorption spectra indicated this compound was not 6-pentyl-2H-pyran-one (6PAP), the volatile antifungal metabolite widely described in Th1. Furthermore, this compound was not produced by Th1 under any culture conditions. Mycelial growth of A. bisporus, Botrytis cinerea and Sclerotium cepivorum was inhibited in the presence of this compound through volatility , diffusion and direct application. This indicates that Th4 produces novel, volatile, antifungal metabolites in the presence of A. bisporus that are likely involved in green mould disease of mushroom crops.

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Label on card stock for "Clarke & Chapman, Packers and Jobbers of Green Apples, Macomb, Illinois, 1870-1878"

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Mildred Sloman is pictured with three unidentified gentlemen in this undated photograph, believed to be taken in London, Ontario. This black and white snapshot was in the possession of the Rick Bell family, whose ancestors include Black slaves from the United States.

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Mildred Sloman, dressed in uniform, is pictured here in this undated black and white snapshot, likely taken in the early 1940s. The Sloman family is descended from former American slaves who settled in Canada. This photograph was among the family memorabilia in the possession of Rick Bell, of St. Catharines, Ontario.