Thesis (Ph. D.)--University of Wisconsin, 1909. / "A selected bibliography": p. 248-254.

Todos os processos industriais são forçados a cumprir especificações de produto através da inserção de rigorosos parâmetros de controle, principaJmente devido à globalização do mercado. A tendência mundial indica que cada vez mais a cor passa a ser um parâmetro primordial para a colocação do produto no mercado. Neste contexto, uma das dificuldades da indústria mineral é a inexistência de equipamentos adequados para a medição da cor de polpas de minério durante o processamento mineral. Isto se verifica principalmente para os minerais industriais que são caracterizados, na maioria das vezes, em termos de índices de alvura e amarelamento. Este traballio tem como objetivo principal avaliar o uso do equipamento Colorcell, utilizado e desenvolvido pela empresa Renner-HerrmaIlll para a produção de tintas, na indústria de processamento mineral. Os ensaios foram realizados com um equipamento similar ao original. Para se compreender as variáveis operacionais do equipamento utilizou-se um produto à base de carbonato de cálcio natural. Após a delimitação das variáveis e definição de uma metodologia de trabalho, foram caracterizados outros minerais utilizados nas indústrias de tintas, papel e plásticos. O sistema Colorcell também foi utilizado para o controle do processamento de caulim de uma empresa da região sul do Brasil. Ensaios em laboratório permitiram o ajuste de um modelo cinético para a etapa de alvejamento da empresa. A tecnologia Colorcell indica que além dos resultados benéficos ao controle de processo é possível correlacionar a caracterização colorimétrica em polpa com o método tradicional de medição de cor.

Todos os processos industriais são forçados a cumprir especificações de produto através da inserção de rigorosos parâmetros de controle, principaJmente devido à globalização do mercado. A tendência mundial indica que cada vez mais a cor passa a ser um parâmetro primordial para a colocação do produto no mercado. Neste contexto, uma das dificuldades da indústria mineral é a inexistência de equipamentos adequados para a medição da cor de polpas de minério durante o processamento mineral. Isto se verifica principalmente para os minerais industriais que são caracterizados, na maioria das vezes, em termos de índices de alvura e amarelamento. Este traballio tem como objetivo principal avaliar o uso do equipamento Colorcell, utilizado e desenvolvido pela empresa Renner-HerrmaIlll para a produção de tintas, na indústria de processamento mineral. Os ensaios foram realizados com um equipamento similar ao original. Para se compreender as variáveis operacionais do equipamento utilizou-se um produto à base de carbonato de cálcio natural. Após a delimitação das variáveis e definição de uma metodologia de trabalho, foram caracterizados outros minerais utilizados nas indústrias de tintas, papel e plásticos. O sistema Colorcell também foi utilizado para o controle do processamento de caulim de uma empresa da região sul do Brasil. Ensaios em laboratório permitiram o ajuste de um modelo cinético para a etapa de alvejamento da empresa. A tecnologia Colorcell indica que além dos resultados benéficos ao controle de processo é possível correlacionar a caracterização colorimétrica em polpa com o método tradicional de medição de cor.

Orientador: Saul Barisnick Suslick / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-07-22T14:49:57Z (GMT). No. of bitstreams: 1 Rodrigues_AntonioFernandodaSilva_M.pdf: 6733965 bytes, checksum: 4b0bd968ca46e070634cbdde209f0b2c (MD5) Previous issue date: 1997 / Resumo: Esta dissertação identifica e analisa alguns aspectos do boom estanífero nacional, dando ênfase aos seus principais fatores determinantes, efeitos e perspectivas setoriais, com o propósito de avaliar sua importância no cenário mínero-econômico nacional, no período de 1980 a 1996. Na década de 80 o segmento estanífero brasileiro experimentou um incremento produtivo súbito, com índices da ordem de 1.365% (1970-1989) e 665%(1980-1989). Consolidou internamente sua condição superavitária entre os produtores de não-ferrosos e apresentou-se ao mercado internacional como importante exportador de estanho metálico, evoluindo de um modesto sexto lugar como produtor no ranking ocidental, em 1980 - abaixo da Austrália, Bolívia, Indonésia, Tailândia e Malásia - para o primeiro posto durante o triênio 1988-1990. Neste contexto, observa-se que o impacto positivo das exportações, associado às vantagens comparativas da jazidas brasileiras, geraram um clima de euforia setorial, dando a falsa impressão de que se absorveria a crise internacional do estanho deflagrada na London Metal Exchange LME, em 1985. Contudo, não obstante a reconhecida competitividade inata às jazidas nacionais, implicações de ordem político-gerencial do boom comprometeram sobremaneira a sustentabilidade do segmento minero-estanífero brasileiro / Abstract: This dissertation identifies and analyzes some aspeets of the Brazilian tin boom. It emphasizes the main determinant faetors, the effeets and the eeonomie perspeetives ofthe seetor, in order to show its role in the Brazilian mining-eeonomie setting, in the period 1980-1996. In the 1980's the Brazilian tin seetor experieneed a sudden growth in tin eontent of ores produetion, about 1,365% (1970-1988) and 665% (1980-1989). The internal market reinforeed its condition showing a surplus among non-ferrous producers and was launehed to the international market as an important exporter of metallie tin, climbing from the sixth plaee, as a produeer in the Western World, in 1980 below Australia, Bolivia, Thailand and Malaysia to the first rank, during the period 1988-1990. In this setting, it ean be seen that the positive impaet of the exports, due to the favorable conditions provided by the Brazilian deposits, eaused an exeess of optimism in the tin business, leading to the impression that the erisis initiated by the London Metal Exehange LME would be overeome. Despite the inherent eompetitivity of the Brazilian deposits, both management and politieal issues eompromised greatly the sustainability ofthe mining-eeonomie Brasilian tin seetor / Mestrado / Administração e Politica de Recursos Minerais / Mestre em Geociências

O presente estudo conduzido na FZEA/USP, teve por finalidade avaliar os efeitos do flúor provenientes do fosfato de rocha e do fluoreto de sódio na fluorose dental de ovinos. Foram utilizados 21 carneiros Santa Inês, os quais foram submetidos a três tratamentos com duração de 140 dias. Os tratamentos foram: Tratamento B: Dieta Controle (fosfato bicálcico) com 13,2 mg de flúor/Kg M.S.; Tratamento F: Dieta suplementada com 98,5 mg de flúor proveniente do fluoreto de Sódio; Tratamento R: Dieta suplementada com 94,5 mg de flúor proveniente do fosfato de rocha. No inicio e a cada 28 dias os carneiros eram pesados e colhidas amostras de sangue para dosagem sérica de flúor e no final do experimento, os animais foram abatidos para colheita de amostras de costela e dentes, para determinação dos teores de F. e análise histológica. Os animais suplementados com fosfato de rocha apresentaram níveis séricos de F superiores ao grupo controle, mas inferiores aos suplementados com flúor de fluoreto de sódio (p<=0,05). Ao final do experimento (40 dias), houve uma tendência (p<=0,08) dos animais da dieta controle ganharem mais peso que os suplementados com flúor do fluoreto de sódio. A suplementação da dieta durante 140 dias com 98,5mg de flúor proveniente do fluoreto de sódio ou com 94,5 mg de F proveniente do fosfato de rocha foi suficiente para aumentar significativamente o teor de F nos ossos. Não foi verificada alteração histológica nos molares de ovinos erupcionados aos 10 meses. / The present study was conducted at FZEA/USP and had the purpose to evaluate the effects of fluorine in rock phosphate and sodium flouride in sheep. Twenty one Santa Inês rams were submitted to three treatments during 140 days. The treatments were: Treatment B: Control diet dicalcium phosphate with 13,2 mg of fluorine/kgDM; Treatment F: Supplemented diet with 98,5 mg of fluorine from sodium fluorine ; Treatment R: Supplemented Diet with 94,5 mg of fluorine from rock phosphate. In the beginning and each 28 days the animals were weighted and blood samples were collected for analyses of fluorine serum concentration. By the end of the experiment, the animals were slaughtered to collect samples of ribs and teeth to determine the fluorine content and for histologic. The supplemented animals with rock phosphate presented higher fluorine serum levels than the control group, but lower than the supplemented ones with fluorine from sodium fluoride (p<=0,05). In the end of the experiment (140 days) there was a tendency (p<=0,08) of the animals control diet to put on more weight than the supplemented with fluorine from sodium fluoride. The supplementation of the diet during 140 days with 98,5 mg of fluorine from sodium fluoride or with 94,5 mg of fluorine from rock phosphate it was enough for a significative increasing in the fluorine concentration in the bones. No histological alteration was detected in the ovine molars broken out while they were 10 months.

O espessamento é uma operação unitária que tem como finalidade separar, por diferença de massa específica entre o sólido e o líquido, sólidos suspensos em meio fluido, pela ação da gravidade. É bastante empregado industrialmente em processos contínuos no adensamento de polpas e minérios, em unidades com reação de precipitação e no tratamento de efluentes, dentre outros. Os equipamentos que realizam esta operação, chamados espessadores, são, em geral, tanques abertos de formato cilíndrico, instalados no eixo vertical com a entrada da suspensão na parte superior central, de fundo ligeiramente cônico para a retirada da polpa espessada e calha circulando o topo para descarga do líquido clarificado. As várias técnicas de projeto destas unidades contínuas são comumente baseadas em ensaios de bancada com provetas. Não é raro ocorrerem para os mesmos dados experimentais, áreas de projeto com desvios superiores a 50%. O presente trabalho visou verificar a validade das técnicas de seleção de TALMADGE-FITCH, ROBERTS e FLUXO DE SÓLIDOS, para o dimensionamento de espessadores industriais com salmoura e lodo biológico. Foram realizados para este fim, ensaios de espessamento em provetas com as próprias suspensões industriais, calculadas as áreas pelas técnicas supracitadas e comparadas com os resultados das secções dos equipamentos contínuos industriais. Os desvios médios dos diâmetros para cada técnica em relação ao espessadores industriais apresentaram contra a segurança dos equipamentos um valor de 42% para o método de Talmadge-Fitch, 45,5% para Roberts e 43,5% para o método do Fluxo de sólidos. Concluiu-se, para as condições estudadas, que os métodos de provetas utilizados forneceram valores na mesma ordem de grandeza e que requerem um fator de escala para o dimensionamento das unidades industriais contínuas. / Thickening is a unit operation that has the goal of solid-liquid separation. The principle of this separation is the difference of specific weight between solid and liquid. This unit operation is used in mineral industries, to ore concentrate, wastewater, and others. The tanks called thickeners are usually open, with the feed on the top of the equipment. The solids discharge is done trough the bottom in a conical shape. The most techniques of sizing thickeners are based on graduated cylinders, and it is a common get result that has a difference area in about 50%. This happens because security coefficient, difficulties for results interpretation and scales factors. This research has the goal to apply the techniques of selection of Solids Flux, Roberts and Talmadge-Fitch in graduated cylinders. These methods are classical for thickener sizing. A comparison has been made between the results by those methods with the data obtained from continuous industrial units for salt solution and biological brine. The shunting line for the techniques obtained was 42% for Talmadge-Fitch, 45,5% for Roberts and 43,5% for Solid Flux in the relationship with industrial thickeners. In conclusion, for the studied condition, all methods showed values in the same order and requires a scale factors to sizing the continuous thickeners.

Foreign ownership and control of major segments of the Canadian economy today, according to many prominent Canadians, present grave problems and offer grim forebodings as to the future ability of Canada to maintain its economic and political independence. In the press, on the political platform, in Parliament, in a Royal Commission Report, and in learned societies, the controversial debate rages with the participants constantly diagnosing the economy's present state of health and busily suggesting a host of remedies. Pre-occupation with the question of foreign ownership and control of the economy is not a twentieth century phenomenon alone. The mining industry of the West Kootenay and Boundary regions of British Columbia in the 1890's—which constituted a significant segment of the economy—was once believed to be almost entirely American owned and controlled, Judge Howay and Dr. Sage, historians, who studied the mining industry in British Columbia, concluded that it was only after 1897 or 1898 that American ownership and control were replaced as "British and Canadian capital began to come into the Kootenays in fairly large quantities." Professor Hansen declared that American activity was strongly in evidence in the mining industry after 1896. Professor Innis stated that the development of lode mining in the Kootenay was the result of the construction of a transcontinental railway which had been primarily designed to handle Pacific Coast traffic. In expanding and focussing the thesis of Professor Innis on the national scene, Professor Creighton insisted that the central objective of national policy after 1867 involved realizing a strong, varied and integrated transcontinental economy. The statements of these authorities have stimulated the present study. New and additional information now has been made available to help to measure the relative control of capital— coastal British Columbian, or interior British Columbian, or other Canadian, or British, or American—in the mining companies of the West Kootenay and Boundary regions, 1890 to 1900. Records pertaining to 1,306 mining companies which were organized and operating in the West Kootenay and Boundary areas at some time between 1890 and 1900 have been examined. Five hundred ten of these companies were either foreign registered or were extra-provincially registered or licensed companies. Information concerning them could only be obtained by examining the British Columbia Gazette and current mining journals. Usually the source of capital has been assumed to be identical with the area of incorporation and with the locale of the head office. Considerably more information is now available on the 762 incorporated companies in British Columbia. Annual returns containing names, and addresses of shareholders and directors and the value of stock held by them provided the means to determine the source of capital for most of these companies. The writer classified these names under the various sources or nationalities. He then determined the total value of stock held by each of these sources for the 762 locally incorporated companies. The source or nationality controlling the company could thus be frequently ascertained. To obtain this information, the writer examined the files of 2,174 companies whose records are preserved on microfilm. The source of capital of a company—if it could be determined—has been noted for the year in which the company was incorporated or registered. This practice has appeared to be satisfactory as examination of annual reports has shown a remarkable absence of transfer of capital control from one group to another. The study is then confined to an examination and comparison of the source of capital of mining companies as determined by the year of incorporation or registration. The thesis is an inductive one. In addition to the above assumptions, lack of sufficient and reliable evidence on the source of capital of 214 companies has caused these companies to be classed under the category of insufficient information. The financial operations and the reasons for the success of a few companies and the reasons for the failure of many companies are examined. Changes in the control and ownership of many of the more important corporations are noted. Important capitalists, promoters and political figures who played a prominent role in financing companies are noted. The basic patterns and trends in capital formation, 1890 to 1900, and in a more general fashion, the trends from 1901 to 1914 are traced. In the period before 1890, the few companies established after the completion of the transcontinental line of the Canadian Pacific Railway in 1885 are briefly described. In the 1890 to 1900 period, American owned companies declined relatively as Canadian and British owned companies increased, but there were always significant numbers of American companies. The Canadian companies played an active role as one of the main agents in stemming the pervasive American influences in the region. After 1898, as Canadian capital controlled a second east-west railway in the South Kootenay and Boundary country, and as Canadians owned the major smelter, the Canadian and British owned mining corporations assisted in integrating the regions into the new Canadian transcontinental economy. Within the eleven year period, 1890 to 1900, three subsidiary movements of capital flow occurred. The first two, from 1890 to 1894—chiefly to the Slocan,—and from 1895 to 1897— chiefly to Rossland—followed the basic pattern of the major movement with an initial heavier emphasis on American capital, and a later swing to Canadian and British capital. The last movement, from 1898 to 1900, followed a different course as there was no large early influx of American capital. It only became more prominent at the end of the movement. Consolidations of mining corporations paralleling consolidations in the other major industries of the Province characterized the period from 1901 to 1914. The Canadian owned Consolidated Mining and Smelting Company, a gargantuan concern by 1914, and even then almost synonymous with mining in the Kootenay, had expanded rapidly after its beginning in 1905. Its growth epitomized the era of consolidation before World War I. / Arts, Faculty of / History, Department of / Graduate

Orientador: Celso Pinto Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-07-23T20:46:41Z (GMT). No. of bitstreams: 1 FuentesCampuzano_CesarOswaldo_M.pdf: 2752559 bytes, checksum: b43afd2d15ae1c39fbe72386949cd76a (MD5) Previous issue date: 1998 / Mestrado

No description available.

This study uses a range of magnetic parameters, eg. Susceptibility (X), Saturation Isothermal Remanence (SIRM), Anhysteretic Remanence (ARM), interparametric ratios (ARM/X, SIRM/X, SIRM/ARM) and coercivity of remanence data (IRM-n/SIRM, (BO)CR), coupled with various dating methods (eg. moss increment counting and radiometric dating) to estimate the magnetic deposition onto some Scandinavian peat bogs. The sites available included 4 from southern Finland, 5 from northern Finland, 2 from northern Norway and 1 from southern Denmark. In addition to the magnetic techniques, a range of chemical determinations (iron, copper, zinc, lead, nickel and, where available, manganese) have been made, or are utilised, for all the peat cores. The reproducibility of the primary magnetic deposition record at Kaurastensuo, southern Finland has been examined. The rise in magnetic particulate concentrations, termed the magnetic 'take-off', was consistently dated to about 1931 for 7 of the 8 cores used, regardless of hummock-hollow micro topography. The persistence of magnetic minerals over timescales of 101-103 years has been examined by means of long core profiles from 4 southern Finnish bogs. The mineral magnetic and heavy metal profiles (iron, copper, zinc, lead and nickel) were in reasonable accord with the development of the individual bogs above different mineral soils. The development of peat profiles is dated from between 8000-9000 years BP using 14C dates spanning both the ombrotrophic and minerotrophic phases. The availability of moss increment counts for the northern Scandinavian sites and 210Pb determinations for Draved Moss, southern Denmark and Mo-I-Rana, northern Norway, has allowed estimates of variation in the magnetic deposition to be made. The northern Scandinavian sites all show increasing deposition from 1900, although maximum surface deposition varies from site to site, between 1.24-22.6 10-6Am2yr-1. The magnetic deposition at Draved Moss was estimated to be 21.6 10-6Am2yr-1 at a subsurface maximum dated to between 1967-1978. The increase in lead deposition at Draved Moss is in reasonable agreement with that of published lead deposition profiles from the same site, using earlier attempts at 210Pb determinations. At Mo-I-Rana, northern Norway the maximum magnetic deposition value is estimated to be 8.65 10-6Am'yr-1 for the surface slice, spanning the last 21 years. Any spatial variation in deposition within the Scandinavian sites appears to be partly masked by site-specific features, for example the close proximity of industrial sources at 2 of the Finnish sites and the iron and steel works at Mo-I-Rana. Magnetic deposition at the latter site is in good agreement with the history of iron and steel production within the region since the turn of the century.