The major aim of this study was to investigate various leaching methods for the recovery of zinc and lead from blended neutral leach residues of &Ccedil / inkur having a composition of 12.59 % Zn, 15.21 % Pb, 6.45 % Fe, 0.054 % Cd. Initially water leaching tests were performed at various conditions of leaching temperature, reaction time and particle size. The optimized conditions for water leaching were found to be 2 h, 95&amp / #61616 / C and 250 g/l pulp density with a final pH of 5.9. However, the zinc recovery value of 10.26 % was not adequate for industrial scale operations itself. In acid leaching trials / acid concentration, temperature, reaction time and particle size were the chosen variables. At the optimized condition of 150 g/l H2SO4, 95&amp / #61616 / C, 2 h at 250 g/l pulp density with a final pregnant solution pH of 4.2, the extraction values were determined as 74.87 % for Zn and 39.59 % for Fe. These recovery values were evaluated as suitable for industrially feasible operations while creating a secondary leach residue of a composition of 4.10 % Zn, 19.17 % Pb, 5.52 % Fe and 85 ppm Cd that would not be suitable for pyrometallurgical lead production. After recovering zinc in considerable amount by hot sulphuric acid leaching, NaCl leaching experiments for the extraction of lead were done on the secondary leach residue by taking temperature, time and pulp density into account. The most promising conditions of brine leaching for lead recovery were found as 300 g/l NaCl, 20&amp / #61616 / C, 15 minutes and 20 g/l pulp density that gave approximately 82 % lead recovery with a final residue of 7.87 % Pb, 6.86 % Zn, 8.79 % Fe.

Made available in DSpace on 2014-06-11T19:28:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-19Bitstream added on 2014-06-13T20:18:13Z : No. of bitstreams: 1 silva_cd_me_jabo.pdf: 179730 bytes, checksum: 9f07c31ef9e1bd2fe12de506cf5e8e6a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A agricultura moderna exige testes rápidos para avaliação da qualidade de sementes para determinar o seu uso potencial. O teste de condutividade elétrica é usado para sementes de muitas espécies, especialmente as de leguminosas. O objetivo dessa pesquisa foi o de avaliar o efeito da temperatura de armazenamento sobre os resultados do teste de condutividade elétrica e da composição mineral da solução de embebição de sementes de feijão (Phaseolus vulgaris L.) armazenadas durante um ano a temperatura de 10 e 25 °C. Foram utilizados três lotes da cultivar IAPAR – 81 (grupo carioca) e três lotes da cultivar IPR – TIZIU (grupo preto) armazenadas em câmara fria a 10 °C e em BOD a 25 °C. As avaliações foram reali zadas em intervalos de três meses ao longo de 12 meses e as variáveis avaliadas foram: teor de água, germinação e vigor (envelhecimento acelerado e condutividade elétrica). O conteúdo de potássio da solução de embebição foi determinado por fotometria de chama e o conteúdo de cálcio e magnésio por espectrofotometria de absorção atômica. Os dados foram analisados segundo o delineamento inteiramente casualizado em esquema fatorial (4 períodos de armazenamento x 3 temperaturas) com tratamento adicional (avaliação inicial) com quatro repetições para cada lote. As sementes das cultivares apresentaram comportamento semelhante no armazenamento. / Modern agriculture requires quick tests to evaluate the seeds quality, in order to determine their potential use. The electrical conductivity test has been used for many species, especially legumes seeds. This research was carried out in order to investigate the relationship between the amount of electrolytes (K+, Ca++ and Mg++) on the seed soaked solution and the vigor measured by electrical conductivity test of bean seeds (Phaseolus vulgaris L.) stored at 10 and 25 °C. Three seed lots cultiv ar IAPAR - 81 (Carioca Group) and three cultivar IPR - TIZIU (black group) were stored in a cold chamber at 10 °C and in a BOD at 25 °C. Eval uations were done in intervals of three months over a 12 months and the variables were: water content, germination and vigor (accelerated aging and electrical conductivity tests). The potassium content in the imbibition solution was determined by flame photometry and the calcium and magnesium contents, by atomic absorption spectrophotometry. The statistics model used was completely randomized design in a factorial (four periods of storage X three temperatures) with additional treatment (initial assessment) with four replicates for each lot. The cultivars showed similar behavior in storage. Electrical conductivity values decreased in the last evaluation and it was not followed by reduction of the ions quantified. The potassium was the ion leached in larger amounts from bean seeds stored, and it´s behavior was closest to the results of electrical conductivity test.

Made available in DSpace on 2014-06-12T16:26:25Z (GMT). No. of bitstreams: 2 arquivo1155_1.pdf: 1441766 bytes, checksum: 3090e50673db4f8353bc6516c2af26b5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Inúmeros estudos científicos vêm sendo realizados no sentido de validar as informações populares referentes ao uso de plantas medicinais. É comum no estado de Pernambuco, assim como em todo o Brasil, a existência de feiras livres que comercializam produtos feitos com ervas e extratos naturais (com composição não padronizada), que associada à suscetibilidade do indivíduo agrava o quadro de acidentes por plantas tóxicas. Estes ensaios tiveram como objetivo a verificação da toxicidade do Extrato Bruto Seco e do Extrato aquoso mimetizando o seu uso popular (na forma de infusão), da folha da planta Vitex agnus castus Linn. popularmente conhecida por erva-de-caboclo e Liamba (PE), alecrim-de-planta (PA) e pau-de-angola (PA e MA). Este projeto visou esclarecer possíveis alterações provocadas pelo Extrato Bruto Seco (EBS) das folhas da Vitex agnus castus Linn no Sistema Nervoso Central e determinar sua toxicidade. A avaliação toxicológica pré clínica aguda (CL50) usando metanáuplios de Artemia salina Leach deu um valor de 801,266 μg/mL para Vitex agnus castus Linn. Os valores obtidos são próximos a 1000 μg/mL, indicando uma baixa toxicidade para esta planta. O extrato aquoso de V. agnus-castus não apresentou DL50 inferior a dose de 4g/kg, indicando baixa toxicidade aguda em ratos. Já o estudo toxicológico pré clínico crônico dos ratos por 90 dias com o EBS das folhas da Vitex anus castus Linn com doses de 2,18 mg/kg (uso popular), 10,9 mg/kg (dose 5x) e 54,5 mg/kg (dose 25x) nas doses usual , 5x a usual, 25x a usual mostrou uma pequena alteração já esperadas das transaminases hepáticas não apresentando nenhuma alteração histopatológica considerável

A disagreement has arisen between the localauthorities (Skellefteå kommun) and Boliden Mineral AB regarding the use of amaterial called

Wireless Sensor Networks (WSNs) have attracted growing interest from both realcustomers and the scientific community in the recent years due to their powerfulcapabilities and varied applications. Each wireless sensor node relays data to thebase station (BS) directly in the direct communication protocol. However, there aresome applications that require some of the nodes to be placed at vast distances fromthe BS, which leads to rapid reduction in the total energy of all nodes. Since energyconsumption in sensor networks is critical, many new protocols have beendeveloped to reduce losses. The Low-energy adaptive clustering hierarchy(LEACH) is one of the most popular protocols that increase network lifetime byreducing losses. In this report, I survey and compare some algorithms and propose a new enhancedalgorithm for the LEACH protocol, thus saving energy and prolonging the networklifespan. MATLAB is used for simulation.

Masters of Science / The redistribution patterns of trace elements related to ore mineralisation in the secondary environment are the foundation of regolith exploration geochemistry. Understanding the controls of these element patterns is important for the detection of underlying ore deposits, especially in areas where bedrock is concealed by extensive regolith. The study area, which hosts PGE and gold deposits within the Stella Layered Intrusion is one such area. A major aim of this study was to use major element data to characterise the regolith materials enclosing the PGE mineralisation in the Stella Layered Intrusion to ascertain the degree of weathering that has occurred. Furthermore, the study aimed to relate the weathering patterns in regolith to the distribution of pathfinder elements of PGEs and gold in areas proximal and distal to the mineralised zones. The study was conducted using XRF data, which included major oxide and trace element data. These data were used to characterise regolith materials (scatter plots, K/Al versus Mg/Al plots) and calculating indices that determine the degree of weathering such as CIA and ICV indices as well as A-CN-K and A-CN-FM diagrams. Signatures of pathfinder/ trace elements were enhanced by hydroxylamine hydrochloride partial selective leach technique. The distribution patterns of the partial leach data were compared to the intensity of weathering and weathering products, e.g. manganese oxides, carbonates in areas proximal and distal to the ore zone. In the Serpens North Prospect, the major horizons that were identified include saprolith, stone line and aeolian sands. Incipient calcrete formation occurs in some parts of the Sirius Prospect, while in some parts, well developed, thick calcrete layers are found interlayered with the saprolith and aeolian sand.

No description available.

No description available.

The late 1990's was a time of great wealth and prosperity in the United States. With this economic fervor came a new era of deregulation of the financial services industry. During this time, Congress passed the Financial Services Modernization Act of 1999, otherwise referred to as the Gramm-Leach-Bliley Act (GBLA). This law removed the final barrier (contained in Depression-era Glass-Steagall legislation) between mixing investment banking and commercial banking in the United States. The purpose of this report is to explain the intentions of the law's supporters and detractors, to discuss why this period was a particularly ripe time for such a policy, to examine the leadership decisions that contributed to the passage of GLBA, and to understand the motives behind a "new Glass-Steagall" bill today. This paper focuses only on the deregulatory parts of GLBA relevant to Glass-Steagall's repeal. It does not examine the privacy protections, et al. of GLBA at any length. Also contained in the analysis is a brief discussion of whether GLBA's stated intentions have been violated through the mixing of banking and commerce that has emerged in the present day. Finally, this report ends with a discussion on the fidelity of our national debate on banking regulation, and what it means for the federal government to manage risk in American financial markets in support of the public interest. / text

Orientador: Roberval Daiton Vieira / Banca: Rubens Sader / Banca: Ana Dionísia da Luz Coelho Novembre / Resumo: A agricultura moderna exige testes rápidos para avaliação da qualidade de sementes para determinar o seu uso potencial. O teste de condutividade elétrica é usado para sementes de muitas espécies, especialmente as de leguminosas. O objetivo dessa pesquisa foi o de avaliar o efeito da temperatura de armazenamento sobre os resultados do teste de condutividade elétrica e da composição mineral da solução de embebição de sementes de feijão (Phaseolus vulgaris L.) armazenadas durante um ano a temperatura de 10 e 25 °C. Foram utilizados três lotes da cultivar IAPAR - 81 (grupo carioca) e três lotes da cultivar IPR - TIZIU (grupo preto) armazenadas em câmara fria a 10 °C e em BOD a 25 °C. As avaliações foram reali zadas em intervalos de três meses ao longo de 12 meses e as variáveis avaliadas foram: teor de água, germinação e vigor (envelhecimento acelerado e condutividade elétrica). O conteúdo de potássio da solução de embebição foi determinado por fotometria de chama e o conteúdo de cálcio e magnésio por espectrofotometria de absorção atômica. Os dados foram analisados segundo o delineamento inteiramente casualizado em esquema fatorial (4 períodos de armazenamento x 3 temperaturas) com tratamento adicional (avaliação inicial) com quatro repetições para cada lote. As sementes das cultivares apresentaram comportamento semelhante no armazenamento. / Abstract: Modern agriculture requires quick tests to evaluate the seeds quality, in order to determine their potential use. The electrical conductivity test has been used for many species, especially legumes seeds. This research was carried out in order to investigate the relationship between the amount of electrolytes (K+, Ca++ and Mg++) on the seed soaked solution and the vigor measured by electrical conductivity test of bean seeds (Phaseolus vulgaris L.) stored at 10 and 25 °C. Three seed lots cultiv ar IAPAR - 81 (Carioca Group) and three cultivar IPR - TIZIU (black group) were stored in a cold chamber at 10 °C and in a BOD at 25 °C. Eval uations were done in intervals of three months over a 12 months and the variables were: water content, germination and vigor (accelerated aging and electrical conductivity tests). The potassium content in the imbibition solution was determined by flame photometry and the calcium and magnesium contents, by atomic absorption spectrophotometry. The statistics model used was completely randomized design in a factorial (four periods of storage X three temperatures) with additional treatment (initial assessment) with four replicates for each lot. The cultivars showed similar behavior in storage. Electrical conductivity values decreased in the last evaluation and it was not followed by reduction of the ions quantified. The potassium was the ion leached in larger amounts from bean seeds stored, and it's behavior was closest to the results of electrical conductivity test. / Mestre