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1
Lewis, Helen. "Characterisation of fluid-flow systems for Irish lead-zinc deposits." Thesis, University of Glasgow, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337511.
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Blood, James. "Electrochemical studies of PbOâ‚‚ battery plate materials and PbOâ‚‚ anodic deposits." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268814.
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Ceyhan, Nuri. "Lead Isotope Geochemistry Of Pb-zn Deposits From Eastern Taurides, Turkey." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/3/1054592/index.pdf.
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This study is concerned with the Pb-isotope compositions of galena samples from Pb-Zn occurrences in southern Turkey. The purpose is to i) provide chronologic information for ore deposition, ii) investigate the likely source(s) of lead in ore
deposits, and iii) examine the possible control of tectonic setting and crustal basement on Pb-isotope compositions. The data used in the study belongs to the
deposits located in Taurides (Zamanti, KahramanmaraS, Malatya, Elazig, Bitlis), with additional data from Nigde Massif and Hakkari Area.
The mineralizations are dominantly carbonate-hosted Pb-Zn deposits formed as fracture and karst fillings and, in some places, parralel to bedding. Ore minerals are mainly Zn-oxides and minor Zn, Pb-sulphides.
The Pb-isotope compositions, as evaluated in terms of their configuration with respect to reference crustal growth curves and reference isochrons on conventional Pb-isotope diagrams, point to U/Pb ratios greater than average crustal values (and close to the Western Mediterranean Crustal Growth Curve) for
all the deposits, indicating upper crustal source for Pb. However, some of the deposits (AfSin-KahramanmaraSOreks, Dü
ndarli, AgcaSar and skarn type deposits to the south of Ç
adirkaya in Zamanti (Kayseri-Adana)
Keban-Elazig) appear to have magmatic inputs in their genesis. Relatively old deposits are likely Paleozoic (Cafana-Malatya and Tü
rksevin-KahramanmaraS), Late Paleozoic-Early Mesozoic (Kalekö
y-Zamanti) and Mesozoic (Hakkari) in age. The rest of the deposits (most of the occurrences in Zamanti, Nigde, KahramanmaraS, Elazig and Bitlis) are likely of Cenozoic age. The Pb-isotope compositions are, in general, similar to those from other occurrences in the Mediterranean Belt.
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Whitbread, Michael Andrew Ian, and n/a. "Lithogeochemichal alteration aound the Century and Elura Zn-Pb-Ag deposits: detecting alteration expressions in deep and near surface environments." University of Canberra. Resource, Environmental & Heritage Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20051129.112425.
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Exploration companies commonly rely on geochemistry to identify alteration of
distinctive geochemical and mineralogical character, surrounding metal sulphide
deposits that were precipitated from hydrothermal fluids. However, examination of
raw analytical data is prone to error due to closure effects and the difficulty in
removing the effects of background variation in unaltered rocks from the variations
imposed by later hydrothermal alteration. Closure can be avoided by using ratios, or
by utilising mass balance approaches based on fixing volume, mass or concentration
changes between samples of parent and daughter lithologies. Using a parent-daughter
approach is limiting, because only pairs of samples can be compared at any one time
and because an unaltered equivalent must be produced for each sample examined in
this way. Pearce Element Ratio analysis and General Element Ratio analysis (PER
and GER) are not restricted in this fashion, and are more amenable to interrogation of
large data sets. PER and GER are also capable of decoupling background variation
from that variation due to hydrothermal alteration. Furthermore, these ratio methods
are readily applied to commercially derived lithogeochemical assays.
In this study, various analytical methods and interpretive techniques (including PER
and GER) have been applied to identify alteration in rocks around the Century and
Elura Zn-Pb-Ag deposits, and to assess whether primary ore-related alteration effects
can still be identified once altered rocks have been subjected to weathering.
Ratios of trace elements over a conserved element have been used to generate a suite
of pathfinder elements for each deposit. Elements enriched in host rocks around both
deposits include the economic metals Zn, Pb and Ag, along with Rb and Tl. Sodium is
ubiquitously depleted in altered rocks. Other elements in the pathfinder suites are
distinctive to each deposit type, and include a number of major and trace elements
that are added or removed from the rocks around the mineralised zones. For example,
Sb and As are enriched in rocks around Elura mineralisation while Ge and Cd are
enriched in samples around Century deposit.
Iron carbonate development accompanied by potassic alteration, the destruction of
albite and the absence of chlorite are the dominant mineral alteration effects at both
deposits. PER and GER diagrams have been used to quantify the intensity of this
alteration and allow lithogeochemistry to be used to vector towards high intensity
alteration, which is adjacent to Century and Elura mineralisation. These ratio methods
are applied to both visibly and cryptically altered rocks at both deposits, and have a
very high degree of success in classifying alteration in unweathered rocks.
The following simple PER ratios indicate proximity to Elura mineralisation:
Ca/C, K/Al for shales, K/(Al-Na) for siltstones/sandstones.
The following simple PER ratios indicate proximity to Century mineralisation:
Mn/Ti, Mg/Ti and Fe/Ti vs C/Ti, K/Ti vs Al/Ti, K/Ti vs (Al-Na)/Ti.
Pathfinder elements can be overlain onto PER and GER diagrams to aid in ranking the
prospectivity of samples, and to assess mineral hosts for individual pathfinder
elements.
Weathering destroys most indicators of alteration in the Elura area, while alteration
signatures are better preserved in host rocks around the Century deposit.
5
Dudek, Nickolas. "Evaluating the Source and Use of Radon for Exploring Deeply Buried Uranium Deposits." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36187.
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This project’s goal is to evaluate the use of groundwater Rn as a tool for the search of deeply buried U deposits. To do so, the concentrations of major cations, anions, Rn, 4He, and 3H were measured in groundwater. Additionally, the abundance, composition, and distribution of radionuclides (U, Ra, 206Pb, 207Pb, 208Pb), were measured in soil and sandstone above the Denison Mines’ Phoenix Deposit (located at a depth of ~450 m).
Rn was extracted from groundwater using mineral oil, and higher groundwater Rn radioactivity (average 0.13 Bq/g of water, n=10) was found in drill holes within ~100 meters of the Phoenix Deposit’s surface projection than in distal holes (average 0.072 Bq/g of oil, n=4). High Rn radioactivity is independent of the drill holes’ intersection with U ore, indicating that drilling did not transport significant amounts of Rn or parent isotopes to shallow depths. The water table is commonly within the Dunlop Member of the Athabasca sandstones, and groundwater Rn is positively correlated with average U concentrations obtained by modified aqua regia digestion of sandstones (analytical code 2AMS at the Saskatchewan Research Council) and also positively correlated with U in three-acid digestion of sandstones (analytical code 3AMS at the Saskatchewan Research Council). Diffusion models show Rn cannot travel significant distances, and so Rn is likely produced in MFd from the in-situ decay of U and Ra.
226Ra radioactivity was measured for B horizon soil samples (n=39) and sandstone samples (n=20) after a HCl leach followed with BaSO4 precipitation. An extraction efficiency for Ra of 28.2%±3.8%. was determined by comparing the soil BaSO4 precipitation procedure against unprocessed soils. Ra radioactivity in B horizon soil is lower than expected from U contents determined with INAA. Ra radioactivity is comparable to the values expected from INAA U concentrations (n=17) in sandstone, with exception to 4 Dunlop Member samples and 2 samples in the Read Formation and Bird Member. Ra in 4 of 5 samples in the Dunlop Member are 10-50% overabundant, perhaps resulting from Ra percolating downwards from soil. The proposed interpretation is consistent with lower than expected Ra radioactivity of B horizon soil. Ra is 260% and 420% overabundant in the two samples from the Read Formation and the Bird Member (1 each), suggesting upward migration of Ra from the U deposit. Low solute concentration and a neutral-weakly alkaline pH of shallow groundwater in the study area appears to prevent significant travel of Ra ions through groundwater by means of ion absorption competition.
Pb isotopic compositions were determined using an ICP-MS for sandstones and soil via three different leaches; 0.02 N HBr, 2.7 N HCl, and concentrated HBr. Overall, Pb isotopic compositions of MFd (n=5) and B horizon (n=10) are similar, supporting the percolation of acidic surface waters through soil. One sample from RD (among 4 samples) show high 206Pb, suggesting an upward migration of 206Pb from the deposit.
The ratios of 4He/3He in ground water ranged between 0.95-1.07; typical of groundwater-atmosphere interaction. The lateral flow of groundwater at deep levels can explain the absence of higher 4He/3He.
6
Goutier, Françoise Mélanie. "Galena lead isotope study of mineral deposits in the Eagle Bay Formation, southeastern British Columbia." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26264.
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The Eagle Bay Formation in the Adams Plateau-Clearwater area, 35km northeast of Kamloops, hosts several economic and sub-economic mineralized occurrences. The age and genesis of these mineral deposits can be estimated by using a specific growth curve which depicts the lead evolution for the Eagle Bay Formation. This curve, named the remodeled curve, represents a local deviation from the average 'shale' curve of Godwin and Sinclair (1982) for the autochthonous part of the Canadian Cordillera. This remodeled curve is specifically applicable to the Adams Plateau-Clearwater area. The lead isotope data from the deposits of the Eagle Bay Formation plot in three distinct clusters along the curve indicating that the lead isotopic signature of the Eagle Bay Formation is upper crustal, and that three periods of mineralization can be recognized or 'fingerprinted'. Accordingly, mineralization cogenetic with Devonian volcanism, and veins related to Cretaceous magmatism can be distinguished by location of galena-lead isotope values within clusters 1 or 3 respectively. Cluster 2 reflects a Late Triassic pulse of mineralization and includes epigenetic veins and stratiform deposits. These deposits are either replacement or cogenetic with their host. The Triassic model age for mineralization that is apparently stratiform and cogenetic raises questions about the currently assigned Cambrian age of associated host rock. To accommodate the lead isotope data a new Upper Triassic unit (T-EBG) within the Eagle Bay Formation is defined.
The distinctive lead isotopic signature between deposits hosted by the Eagle Bay Formation is valuable as a guide for future mineral exploration programs in the Adams Plateau-Clearwater area. Recognition of lead isotopic fields that fingerprint types of mineral deposits, provides a useful and practical framework for the classification and evaluation of new mineralized prospects in the area.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
7
Smyth, D. "Biogeochemical prospecting applied to deposits of orthomagmatic copper-nickel-PGE, lode gold and lead in Ireland." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390857.
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Latorre, J. J. "Exploration for stratabound copper, lead and zinc deposits in the Damara-Katanga orogen, central-southern Africa." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005558.
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The Damara-Katanga orogen in central-southern Africa represents an area of 1.73xl0⁶ sq. km. The region is considered one of the wealthiest metallogenic provinces in the world. Successful exploration for stratabound base-metal deposits has taken place at this particular area since the introduction of more organised methodology in the early 1920s. The genesis, location and distribution of the ore deposits are related to their tectonic settings. Geodynamic evolution of the orogen, which initially formed part of a complex Pan-African rift system, comprises the following stages rifting; downwarping, including spreading on the western portion; syn-orogeny and late-orogeny. Two major tectonic events in the history of the region have been identified: the Katangan (900-750 Ma) and the Damaran episodes (750-500 Ma). Timing of mineralisation of ore deposits has been related to the evolutionary stages of the orogen. Genetic models of the most productive deposits are briefly discussed in this dissertation. The sedimentological, geochemical, paleogeographic and structural features can be employed as geological guidelines for integrated exploration programmes. Discoveries of major deposits and prospects in the orogen are also summarised, focussing on the exploration methods employed. The cost-effective use of the exploration techniques includes the classical copper-lead-zinc soil sampling for residual soils such as those in the Copperbelt area. Airborne magnetics and electromagnetics and follow-up ground geophysics have proved successful in areas where the cover is transported in the search for shallow ore deposits such as the Matchless massive sulphides. Remote sensing, geochemical and geophysical techniques have been tried in covered areas of western Botswana. The lack of geological control makes this interpretation difficult. A detailed geological mapping and the use of geochemical and geophysical techniques has been used to delineate carbonate-hosted base-metal deposits at the Otavi Land. The more expensive traditional methods necessary for the delineation of orebodies, such as pitting, trenching and drilling, are also discussed. Using a sequential approach, a possible exploration strategy is suggested, outlining the cost-effective use of remote sensing, geochemical and geophysical techniques. Standardisation in basic geological information is required for future successful explorations in the Damara-Katanga orogen, as well as attractive mining policies. In the event of their implementation, exploration perspectives are promising, specifically in terms of ore potential.
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Andrew, Anne. "Lead and strontium isotope study of five volcanic and intrusive rock suites and related mineral deposits, Vancouver Island, British Columbia." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26953.
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Lead isotope compositions have been obtained from five major volcanic and intrusive rock suites and several ore deposits on Vancouver Island. Lead, uranium and thorium concentrations and strontium isotope ratios have been obtained for a subset of these samples. The rock suites examined are the Paleozoic Sicker Group, Triassic Karmutsen Formation, Jurassic Island Intrusions and Bonanza Group volcanic rocks, and the Eocene Catface intrusions.
Isotope geochemistry of the Sicker Group is consistent with the interpretation that it formed as an island arc. Relatively high 207pb/204pb ratios indicate sediment involvement in the subduction process, which suggests that the Sicker Group formed close to a continent. Buttle Lake ore deposits display decreasingly radiogenic lead isotope ratios with time, suggesting that the associated magmas become increasingly primitive. This supports the hypothesis that these deposits formed during the establishment of rifting in a back-arc environment.
Karmutsen Formation flood basalts display isotopic mixing between an ocean island-type mantle source and average crust. Isotopic evidence is used to support a Northern Hemisphere origin for these basalts.
Mixing is apparent in the lead and strontium isotope signatures of the Island Intrusions and Bonanza Group volcanic rocks, between depleted mantle and crustal (possibly trench sediments) components. This is consistent with formation of these rocks in an island arc environment.
Eocene Catface intrusions have relatively high 207pb/204pb indicating that crustal material was involved in their formation. There are two groups of plutons corresponding to an east belt and west belt classification. Galena from the Zeballos mining camp related to the Eocene Zeballos pluton indicates that the mineralization was derived from the pluton.
Galena lead isotope data from Vancouver Island may be interpreted in a general way by comparison with data from deposits elsewhere of known age and origin. No single growth curve model can be applied. Lead isotope characteristics of Vancouver Island are clearly different from those of the North American craton, reflecting the oceanic affinities of this terrane.
A new technique has been developed to compare 207pb/204pb ratios between samples with differing 206pb/204pb ratios. The procedure projects 207pb/204pb ratios along suitable isochrons until they intersect a reference value of 206pb/204pb. This technique can be used for interpreting lead isotope data from old terranes, in which lead and uranium may have undergone loss or gain, and if lead and uranium abundances have not been measured.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Leonel, Letícia Gameiro. "Aplicação de variáveis indicadoras na avaliação da incerteza volumétrica em um depósito de Zn-Pb." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/44/44137/tde-24022016-092459/.
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Santa Maria é um projeto de exploração mineral conduzido pela empresa Votorantim Metais Ltda, com foco nas comodities zinco e chumbo. Localizado no estado do Rio Grande do Sul, próximo das antigas minas de Camaquã e Uruguay, o projeto se encontra em uma região geologicamente fértil para exploração mineral. O depósito de Santa Maria possui informações suficientes para permitir a avaliação dos recursos minerais e também estudos de viabilidade econômica de projeto, entretanto, sua mineralização ocorre de forma heterogênea e condicionada a feições geológicas estruturais complexas, inserindo dúvidas à respeito da forma e volume dos corpos mineralizados. O objetivo desta pesquisa é a avaliação da incerteza associada à modelagem dos corpos mineralizados. Essa avaliação foi realizada através da comparação entre o modelo tridimensional confeccionado por interpretação de seções e outros dois modelos probabilísticos: um gerado por krigagem de indicadoras e outro gerado por simulação sequencial de indicadoras, que permitiu a interpretação da incerteza associada. Com os resultados obtidos foi possível quantificar os valores de volume máximo, mínimo e médio esperado no depósito, além de avaliar regiões de maior e menor confiança. A utilização conjunta dos métodos de krigagem de indicadoras e simulação sequencial de indicadoras se mostrou uma excelente opção para avaliação do modelo interpretado. Através do tratamento dos resultados foi possível obter informações à respeito da variabilidade local e global do depósito e sobre o comportamento espacial da mineralização. Os resultados e interpretações obtidos podem ser aplicados em trabalhos futuros no depósito, como na classificação do recurso mineral, no refinamento do modelo geológico e no planejamento de futuras malhas de sondagem infill.Santa Maria is a mineral exploration project conducted by Votorantim Metais Ltda, with focus on zinc and lead extraction. The project is located in the state of Rio Grande do Sul, in the vicinities of the old mines of Camaquã and Uruguay, a favorable area for mineral exploration. There is enough information about Santa Maria\'s deposit to allow the estimation of mineral resources and the project\'s economical viability study, however, its mineralization occurs in heterogeneous ways and is conditioned to complex geological structural features, casting doubts about the shape and volume of the ore bodies. The main goal of this research is evaluating the uncertainty associated with the modeling of the orebodies. This evaluation was performed by comparing a three-dimensional model created by section interpretation and other two probabilistic models: one generated by indicator kriging, and the other generated by sequential indicator simulation, which allowed the interpretation of the associated uncertainty. Based on the obtained results, it was possible to quantify the maximum, minimum and average expected volume of the deposit, and also to evaluate the regions of most and least reliability. The joint use of indicator kriging and sequential indicator simulation methods proved to be an excelent tool for evaluating the interpreted model. By processing the results it was possible to obtain information about deposit\'s local and global variability and spatial behavior of mineralization. The obtained results and interpretations can be applied in deposit\'s further sutdies, for instance, to classify the mineral resource, to refine the geological model or to plan future infill drilholes.
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Uazeua, Kakunauua. "Mineralogical, geochemical and lead isotopic analysis of the lead mineralization of the Skorpion Deposit, south western Namibia." Thesis, Rhodes University, 2019. http://hdl.handle.net/10962/68391.
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The Skorpion none-sulphide Zinc Deposit is located in the para-autochtonous Port Nolloth Zone of the Gariep Belt, which overlays the Lower-Proterozoic Orange River Group basement rocks (Corrans et al., 1993). Situated in close proximity to the larger Rosh Pinah Zn-Pb deposit, the Skorpion Deposit contained a resource of 24.6 Mt at 10.6 % Zn and unquantified Cu and Pb prior to mining. To date, zinc has been the only metal exploited, with minor amounts of copper as a by-product. This study aims at understanding the mineralogical composition of the Skorpion lead mineralization and understanding the relationship between lead and the major metals such as zinc and copper in order to form a basis for further work that could determine the potential of processing lead as a by-product. As part of the study, work was also done on lead isotopes mainly with the aim of understanding the mineralization genesis and to determine the differences between the Skorpion and Rosh Pinah deposit which rationalize the inferior economic potential of the Skorpion lead mineralization. Results of the study have shown that majority of the lead mineralization is hosted by the felsic metavolcanics as galena and subordinately in the metasiliciclastics as pyromorphite, a lead manganese phosphate. In terms of the mineral textures, the lead minerals appear to be mainly secondary phases that have been remobilized and reprecipitated around pyrite, within pyrite cracks and intergrown with minerals such as chalcocite and greenockite. Lead has been mainly concentrated along fault zones. The elevated pyromorphite concentrations tend to occur within gossanous zones in close association with iron and manganese oxides. These textures represent supergene enrichment of a sulphide proto ore. However, contrary to copper and zinc mineralization, lead was not remobilized far from the proto ore merely as a function of its poor mobility in acidic fluids (Reddy et al., 1995). This substantiates the concentration of secondary lead in the felsic metavolcanics and to a much lesser extent, in the metasiliciclastics. Both secondary zinc and copper were reprecipitated in the metasiliciclastics, further away from the sulphide proto ore, hosted mainly by the felsic metavolcanics. The average lead isotope ratios of 206Pb/204Pb (17.26), 207Pb/204Pb (15.60) and 208Pb/204Pb (37.42) resemble results provided by Frimmel (2004) for both the Skorpion and Rosh Pinah deposits. For the Skorpion samples from Frimmel (2004) had the following average ratios: 206Pb/204Pb (17.29), 207Pb/204Pb (15.59) and 208Pb/204Pb (37.51). The Rosh Pinah samples had the following average ratios: 206Pb/204Pb (17.17), 207Pb/204Pb (15.61) and 208Pb/204Pb (37.45). These results indicate lead derivation from the lower 2.0 Ga Eburnean pre-Gariep basement in agreement with and Frimmel et al. (2004). The host felsic metavolcanics might have been derived from melting of the basement rocks during the formation of the Adamastor Ocean. In comparison to the Rosh Pinah deposit lead isotope signatures, the Skorpion lead isotopes overlap with the Rosh Pinah deposit isotopes, but have a much narrower range. This is an indication of a much shorter lived and potentially faster mineralization event contrary to the SEDEX type Rosh Pinah deposit. The smaller tonnage of the Skorpion deposit, its inferior lead concentrations and the elevated radiogenic lead isotopes point toward a VMS deposit which was formed in a small graben fed by shallow conduits during a short lived mineralization event. Sedimentary rocks covered the forming deposit at a fast rate and impaired the deposit advancement. The interaction between the upper crustal rocks and the mineralizing fluids is what may have resulted in the elevated radiogenic lead signature. In contrast to this, SEDEX deposits such as the Rosh Pinah Deposit, are generally fed by deep seated conduits that allow more longer lived leaching of metals from the underlying basement rocks and generally allow minor influence from upper crustal rocks.
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Banks, D. A. "On the origin of the Tynagh lead + zinc + copper deposit, Ireland." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382386.
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Lardeau, Maria. "Mineralogie et petrogenese du minerai sulfure du gisement volcano-sedimentaire a zn-cu-ba-(pb-ag) de chessy-les-mines (rhone) : application a l'etude des amas sulfures metamorphises." Orléans, 1987. http://www.theses.fr/1987ORLE2053.
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L'etude petrogenetique des minerais de chessy-les-mines a permis de preciser la nature de la mineralisation et l'etude des deformations, de retracer l'evolution geologique complexe. Il est apparu que les metamorphismes ont amene une homogeneisation et une purification chimique des mineraux du minerai alors que leur recristallisation lors de la mise en place du granite a entraine un rajeunissement chimique. Cette approche petrogenetique et geochimique renforce la parente genetique entre chessy-les-mines et saint bel
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Cox, Nicholas David. "Geology of the Mount Costigan lead-zinc deposit, west-central New Brunswick." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5980.
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The Mount Costigan Pb-Zn deposit is located about 40km east of Plaster Rock, New Brunswick within the Early Devonian Costigan Mountain Formation, in the Matapedia Cover Sequence (formerly the Cialeur Bay Synclinorium). It occurs about 250m east of the summit of Mount Costigan within a series of brecciated and unbrecciated crystal and lapilli tuff, rhyolite and minor siltstone which are exposed in six trenches (North, South, East, West, Southwest and Central). To the west the Costigan Mountain Formation is overlain by the Wapske Formation. The most significant feature of the deposit is the large amount of brecciation, which, in the Central Trench, also serves as the main sulphide host. Petrographic studies indicate that the breccia consists of angular to subangular blocks of massive and banded crystal tuff, massive to spherulitic to flow-banded rhyolite and minor lapilli tuff. The Mount Costigan deposit is interpreted to represent a base metal variety of epithermal deposit. (Abstract shortened by UMI.)
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Bradford, John Allan. "Geology and genesis of the midway silver-lead-zinc deposit, north-central British Columbia." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27398.
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The Midway Ag-Pb-Zn manto deposit is hosted in Middle Devonian McDame Group limestones of the Cassiar Terrane, a displaced segment of the North American miogeocline. In the map area (1040/16), platformal carbonates and siliciclastics of Cambrian to Devonian age are unconformably overlain by Devono-Mississipian basinal sediments, including exhalites (Earn Group). These are structurally overlain, above a flat lying decollement, by Upper Paleozoic marginal basin sediments, basaltic volcanics, intrusives and ultramafites (Sylvester allochthon). The decollement represents the boundary between Cassiar Terrane and Slide Mountain Terrane in the map area.
Jurassic contraction of the North American margin and emplacement of the Sylvester allochthon produced southeasterly trending major and minor structures. Cretaceous - Tertiary extension, linked to transcurrent motion along the Kechika and related faults, produced the north trending high angle Tootsee River fault zone, which divides the map area.
Two intrusive suites, of mid-Cretaceous (100 Ma) and Late Cretaceous (70 Ma) ages, are documented by K-Ar dating. The Late Cretaceous episode is evidenced by large sericite - pyrite alteration zones southeast of Midway, but only a few felsic porphyry dykes are exposed at current erosion levels.
High angle faults in the Tootsee River fault zone confined intrusion driven hydrothermal fluid migration up plunge from an intrusive centre about 2 kilometres southeast of Midway. Fluids were ponded in a southeasterly plunging antiformal trap, and massive sulphides deposited in zones of pre-existing karst breccia porosity beneath a relatively impermeable shale cap. Fe and Cu rich pyrrhotitic assemblages occur at greater depth toward the intrusive centre, with sulphosalt rich pyritic assemblages at shallower depths to the north.
Immiscible aqueous - carbonic liquid and vapour were trapped in quartz deposited with sulphides at 300-340OC. Later lower temperature inclusions record the progressive loss of CH₄ and CO₂ from the system. Salinities were about 7-10 weight % NaCl equivalent. Sulphur isotopes of sulphides span a narrow range, indicating a well mixed reservoir and H₂S dominated environment. Both sedimentary and igneous sources are indicated. Oxygen isotopes of carbonates demonstrate large ¹⁸O depletions due to extensive meteoric water interaction. In a regional context (Rancheria silver district), Midway lead isotopes suggest mixing of upper crustal lead from country rocks with intrusion derived lower crustal lead. Cassiar Terrane epigenetic deposits are distinguished from epigenetic deposits of Slide Mountain Terrane, which have significant mantle lead, consistent with derivation from oceanic and arc host rock assemblages.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Li, Ning. "Depositional controls and genesis of the Jinding sandstone-hosted Zn-Pb deposit, Yunnan Province, Southwest China /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Thesis (Ph. D.)--University of Texas at Austin, 1998.Vita. One folded ill. in pocket. Includes bibliographical references (leaves 222-235). Available also in a digital version from Dissertation Abstracts.
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Cheshire, D. A. "The lithology and stratigraphy of the Anglian deposits of the Lea basin." Thesis, University of Hertfordshire, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373012.
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A revised lithostratigraphy and palaeoenvironmental history of Anglian sediments in Hertfordshire and west Essex is based on field observations and laboratory analysis of samples from 79 sites within the Lea basin and adjacent areas. Analyses included particle size, acid solubility and small clast lithology of tills, pebble counts of gravels, small clast lithology of sands, till macrofabric and palaeocurrent determinations of sands and gravels. Multivariate analyses of the petrographic properties showed that the till samples could be divided into four main groups. Similarity networks, augmented by field relations, identified four till lithostratigraphic units, which merge north-eastwards. Four gravel lithostratigraphic units were also identified from multivariate analysis of petrographic data. The oldest unit, the Westmill Lower Gravel Member, was deposited by the proto-Thames, and can be followed from the middle Thames region into the mid-Essex depression. Eastward flow was disrupted by the advance from the north-east of ice depositing the first (Ware) till. This caused the formation of ice marginal lakes. A temporary southward spillway was initiated in the lower Lea valley from the Watton Road Laminated Silt lake, but permanent diversion of the Thames was effected by a spillway from the Moor Mill Laminated Clay lake, dammed by Ware Till ice near its southwesterly maximum in the Vale of St. Albans. Three readvances followed, depositing lodgement tills named the Stortford, Ugley and Westmill Till Members. Of these, the Stortford Till is the most extensive, reaching the southern margin of glaciation at Finchley and Hornchurch. Gravels deposited during or between these three advances are the Smug Oak Gravel in the Colne Basin, and the Westmill Upper Gravel in the Lea basin. The latter is divided into the chalk-poor Hoddesdon Gravel Bed and the chalky Ugley Gravel Bed.
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Anderson, Iain Kerr. "Ore depositional processes in the formation of the Navan zinc/lead deposit, Co. Meath, Ireland." Thesis, University of Strathclyde, 1990. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23503.
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Burtt, Martin David. "Geology of the B-baseline zone, Walton barium-copper-lead-zinc-silver deposit, Nova Scotia." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10065.
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The Walton Ba-Cu-Pb-Zn-Ag deposit, Nova Scotia, is hosted by Visean-aged carbonate rocks of the Macumber Formation and its associated breccia. The Macumber Formation in the Walton area is divided into two units, the lower Macumber, a laminated carbonate 30-40$\sp\prime$ thick and the upper Macumber, a synsedimentary slump breccia that forms two mounds up to 70$\sp\prime$ thick. Outside the immediate mine area the carbonate is either limestone or dolostone; the Macumber Formation surrounding the deposit has been altered by hydrothermal fluids to manganiferous siderite. Based on barite and metal content two main ore types were defined. Type I comprises barite and variable sulphide contents, whereas Type II comprises only sulphides. Type I ore forms a stratiform sheet which straddles the upper Macumber/lower Macumber contact and contains lenses of Pb-rich and Cu-rich ore. Type II ore is most commonly associated with the upper Macumber mounds where it forms a large pod which cuts the Type I ore zone. The host stratigraphy is presently steeply dipping and faulted, both of which are considered to be post-ore events. The Walton deposit probably formed when uplift of the Cobequid Highlands in the late Namurian initiated gravity-driven flow of basinal fluids through a basal aquifer within the Horton Bluff Formation. The hot fluids flowed south toward the basin margin and leached salts and metals from the aquifer. In the Walton area these fluids were released, along faults, into the overlying Macumber carbonate and synsedimentary carbonate breccia, replacing them initially with manganiferous siderite. (Abstract shortened by UMI.)
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Militon, Christian. "La metallogenie polyphasee a zn-pb-ba-f et mg-fe de la region de gedre-gavarnie-barroude (hautes-pyrenees)." Orléans, 1987. https://tel.archives-ouvertes.fr/tel-00798146.
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Une prospection geologique systematique de ces terrains a conduit a la reconnaissance de quatre principaux types de mineralisations dans le socle, le devonien inferieur et le cretace : 1 - une mineralisation stratiforme a zn-pb-ba-f de type sedimentaire - exhalatif omnipresente au sommet de la barre calcaire emsienne (devonien inferieur). 2 - de nombreux filons de types b. P. G. C. A gangue de siderite avec, pour certains, presence importante de barytine ou de fluorine ; ces filons correspondent a une phase de mineralisation tardi-hercynienne, probablement en liaison avec une phase tectonique compressive impliquant un contexte decrochant a composante cisaillante senestre, evoluant progressivement vers une distension nord-sud. 3 - des amas metasomatiques a mg-fe dans la barre calcaire emsienne, pouvant representer le sommet du systeme hydrothermal responsable des filons tardi-hercyniens du socle. 4 - la dissemination de galene dans les calcaires du santonien et de petits amas decimetriques de barytine secants sur la dolomie greseuse du cenomanien ; ces indices traduisent la remobilisation de filons tardi-hercyniens principalement d'apres l'identite des compositions isotopiques du plomb.
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GUY, ANITA LOUISE. "THE EFFECT OF UNDERPOTENTIALLY DEPOSITED LEAD THIN FILMS ON SURFACE ENHANCED RAMAN SCATTERING AT SILVER ELECTRODES." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183882.
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This dissertation details the effect of underpotentially deposited (UPD) Pb on the surface enhanced Raman scattering (SERS) ability of roughened polycrystalline Ag electrodes. The deposition of monolayer and submonolayer amounts of Pb results in a quenching of the SERS response for pyridine and Cl⁻ adsorbed at Ag electrodes. Various factors which may contribute to the loss of SERS intensity are investigated. The most significant factors include changes in surface roughness features brought about by Pb UPD, changes in surface electronic properties of Pb-modified Ag and changes in a chemical contribution to surface enhancement. Possible changes in surface roughness properties of the Ag electrode due to Pb deposition are examined using scanning electron microscopy (SEM) and SERS reversibility studies. SEMs of roughened Ag electrodes before and after Pb monolayer deposition show no significant change in the morphology of the larger roughness features. However, the deposition and stripping of 60 - 70% of a Pb monolayer results in a loss of ca. 50% of the original SERS intensity for both adsorbate bands. This irreversible loss of SERS intensity is attributed to the destruction of atomic scale roughness (ASR). These results suggest that ca. 50% of the observed SERS response arises from a mechanism involving ASR. In addition, the destruction of ASR is shown to be largely responsible for the quenching of SERS at higher Pb coverages. The morphology of the SERS quenching profiles at lower Pb coverages for pyridine and Cl⁻ varies as a function of excitation wavelength. Experimental quenching profiles are compared with theoretical quenching profiles based on an electromagnetic contribution to SERS. Theoretical quenching profiles are calculated using a model for electromagnetic enhancement at a overlayer-covered ellipsoids proposed by Murray. The experimental results for both adsorbates are in agreement with the theoretical predictions for laser excitation in the blue. Experimental results in the green and red wavelength regions are best explained in terms of photoassisted charge-transfer mechanisms for surface enhancement.
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Rizzi, G. "The sedimentology and petrography of Lower Carboniferous limestones and dolomites : host rocks to the Navan zinc-lead deposit, Ireland." Thesis, University of Glasgow, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294560.
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Wookey, Philip Andrew. "Effects of dry deposited sulphur dioxide on the decomposition of forest leaf litter." Thesis, Lancaster University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328496.
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CHEN, SONG LING. "Application de la teledetection a la metallogenie de la montagne noire et de l'albigeois (massif central)." Toulouse 3, 1987. http://www.theses.fr/1987TOU30159.
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Mertens, Fleury Katharina. "Leiden lesen Bedeutungen von compassio um 1200 und die Poetik des Mit-Leidens im 'Parzival' Wolframs von Eschenbach." Berlin New York de Gruyter, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?id=2866255&prov=M&dok_var=1&dok_ext=htm.
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Bergami, Giulia. "Il paleolago del Timpone Pataso nel contesto evolutivo del Monte Sant'Angelo (Lipari) durante l'Epoca Eruttiva 5." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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In questo lavoro di tesi si è proceduto ad analizzare i depositi piroclastici delle Epoche Eruttive 5a e 5b relative all’attività del Monte Sant'Angelo nell’intervallo temporale tra <114 e 104 ka. Sono state analizzate in dettaglio le sequenze di depositi delle formazioni Timpone Pataso e Serra Pirrera e la loro origine è stata ricondotta a pyroclastic density current (PDC), a variabile concentrazione e contenuto d'acqua (wet), come testimoniato anche dalla presenza di strutture da slumping, di frane sin deposizionali e della presenza di resti vegetali (Chamaerops humilis, Laurus, Pinus, Quercus ilex, cytisus aeolicus, ecc..). Sono stati studiati in dettaglio i depositi del membro tpa della formazione Timpone Pataso, riconducibili ad una successione di riempimento di un paleolago di origine tettonica durante un periodo intereruttivo di quiescenza. Sono state quindi distinte tre sequenze deposizionali (Tipo A, B, C) caratterizzate da un’associazione complessa tra depositi vulcanoclastici e strati di selce. Esse sono state messe in relazione a flussi iperpicnali (Tipo A e B) ed ipopicnali (Tipo C), generati durante piogge intense, che venivano drenati all’interno di un paleolago alcalino (pH>9) con conseguente deposizione di materiale vulcanoclastico e diluizione delle sue acque. Quest’ultimo processo, associato ad un diminuizione del pH a valori minori di 8, è ritenuto responsabile della deposizione delle lamine di selce da acque sovrassature in silice. Le indagini svolte ed i risultati ottenuti sono stati elaborati in collaborazione con il professor Giorgio Gasparotto (Università di Bologna); mentre per i dati paleoambientali ci si è avvalsi della consulenza del Dott. Pietro Lo Cascio, illustre studioso dei paleoambienti eoliani.
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Zambianco, Edmar Casarin. "Avaliação da qualidade de pulverização em plantas de tomate utilizando diferentes pontas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-16122013-165050/.
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A tecnologia da aplicação tem papel fundamental na agricultura, pois proporciona uma correta aplicação do produto biologicamente ativo no alvo, ocasionando um melhor aproveitamento dos agrotóxicos. O objetivo do trabalho foi avaliar a influência de diferentes pontas e pressões na qualidade da pulverização na cultura do tomate por meio da quantificação do depósito e da cobertura foliar. Foram estudadas as pontas GA 11002 (jato plano com indução de ar), TTJ 60-11002 (jato plano duplo) e TT 11002 (jato plano padrão), todas nas pressões de 200, 350 e 500 kPa. Para todos os tratamentos a taxa de aplicação foi de 180 L ha-1. O percentual de cobertura foliar foi quantificado por meio da análise de imagens que detectaram o traçador fluorescente LRM 100 com o auxílio de luz ultravioleta. As imagens foram capturadas por uma câmera digital e processadas pelo software QUANT. O depósito foi quantificado pela extração e quantificação do traçador azul brilhante FD&C N°1 por meio de espectrofotometria. Para ambos os parâmetros foram analisadas amostras do estrato superior e inferior da planta. Houve diferença estatística somente para a cobertura foliar, sendo que na parte superior da planta a ponta de jato plano duplo apresentou menor cobertura na menor pressão. Nas maiores pressões houve um aumento da cobertura foliar favorecido pela formação de gotas médias e finas pelas pontas avaliadas. No estrato inferior a eficiência na cobertura foliar da ponta de jato plano diminui com o aumento da pressão. O depósito de pulverização foi favorecido pelo aumento da cobertura foliar.The application technology plays a key role in agriculture as it provides a correct application of the product biologically active in the target, causing a better use of pesticides. The aim of this study was to evaluate the influence of different nozzles and spray pressures acting on tomato by quantifying the deposit and leaf coverage. Were studied the nozzles GA 11002 (flat fan air induction), TTJ 60-11002 (twin flat fan) and TT 11002 (standard flat fan), all pressures of 200, 350 and 500 kPa. For all treatments, the application rate was 180 L h-1. The percentage of leaf coverage was quantified by image analysis to detect the fluorescent tracer LRM 100 with the aid of ultraviolet light. The images were captured by a digital camera and processed by software QUANT. The deposit was quantified by extraction and quantification of tracer bright blue FD&C N° 1 by spectrophotometry. For both parameters were analyzed samples of top and bottom of the parts plant. Statistical difference only for leaf coverage, and at the top of the plant to twin flat fan nozzles showed lower coverage in less pressure. In the higher pressures there was an increase of leaf coverage favored by the formation of fine droplets medium and evaluated nozzles. In the bottom part plant coverage efficiency of foliar flat fan nozzles decreases with increasing pressure. The spray deposit was favored by increased leaf coverage.
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Erul, Nedim. ""Lean six sigma" in Dienstleistungsprozessen : eine Analyse der Erfolgspotenziale /." Saarbrücken : VDM, Müller, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2951976&prov=M&dok_var=1&dok_ext=htm.
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Stalder, Marcel. "Petrology and mineral chemistry of sulphide ores and associated metalliferous rocks of the Gamsberg Zn-Pb deposit, South Africa : implications for ore genesis and mineral exploration." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16072.
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Thesis (PhD)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: The Gamsberg Zn-Pb deposit is a metamorphosed and multiply deformed sediment-hosted base metal deposit in the central Namaqua Province of South Africa. The deposit is hosted by the Bushmanland Group, a late Palaeoproterozoic (2000-1600 Ma) supracrustal succession of quartzite, metapelitic schist and interbedded metavolcanic rocks. Mineralisation occurs within the central part of the Gams Formation, a heterogeneous sequence of metamorphosed metalliferous sediments and fine-grained organic-rich shales. The ore horizon is subdivided into a lower unit of metapelite-hosted ore, an intermediate layer of phosphorite-hosted ore, and an upper unit of banded garnet-apatite ore. The ore body is enveloped by unmineralised silicate-, carbonate- and oxide-facies metalliferous rocks, which originally represented mixtures of Fe-Mn-rich hydrothermal precipitates, authigenic carbonate, and variable concentrations of detrital material. Based on mineralogical and geochemical characteristics, the metalliferous host rocks are subdivided into iron formations, coticules, Fe-Mn silicates, impure marbles and barite/Ba-rich quartzite. Minerals of the Gams Formation mostly represent solid solution between the Fe and Mn end-members of garnet, pyroxene, pyroxenoid, amphibole, olivine, spinel and ilmenite. Calcium-rich rock types are a typical feature and characterized by the occurrence of manganoan calcite, clinopyroxene, andradite-rich garnet and titanite. A successive increase in the (Mn+Ca):Fe value of rocks and minerals is evident with increasing distance from the ore horizon. Amphibole is restricted to Fe-rich ore-bearing assemblages, whereas orthopyroxene, clinopyroxene, Fe-rich pyroxenoid and olivine are present in intermediate assemblages, and Mn-rich rhodonite and pyroxmangite in the most manganiferous assemblages. These variations are mimicked by an increase in the Mn:Fe value of coexisting garnet and ilmenite group minerals with increasing distance from ore. LA-ICP-MS analyses have been used to constrain the REE patterns of garnet and apatite. In the ore-body, these minerals display a positive Eu anomaly, which is interpreted to reflect a distinct hydrothermal signature. In contrast, garnet and apatite in unmineralised metalliferous rocks display nil or a negative Eu anomaly. Primary features of the Gams Formation, such as REE patterns, the banded nature of garnet-apatite ore, the presence of diagenetic apatite nodules, and the distribution of the redox-sensitive elements Ba and Mn have been used to constrain palaeo-environmental conditions. The results indicate that metapelitehosted ore has been deposited in a stratified ocean that was characterised by anoxic bottom waters and precipitation of Fe and Zn sulphides into organic matter-rich shales. These rocks were superceded by phosphorite-hosted ore, garnet-apatite ore and metalliferous host rocks that developed in a suboxic to oxic environment. The large size of the deposit, the internal lamination of the ores and the predominance of sphalerite and barite are consistent with a vent-distal setting and precipitation of the ore-forming constituents from dense and reduced hydrothermal fluids, which originated due to reactivation of dormant growth faults. Collectively, the geological evidence indicates that Gamsberg is bridging the gap betweenthe SEDEX and BHT classifications. The relationships demonstrate that differences between these two classes of sediment-hosted Zn-Pb deposits are predominantly related to environmental conditions within localised third order basins and not to fundamental differences in ore-forming processes.
AFRIKAANSE OPSOMMING: Die Gamsberg Zn-Pb afsetting is ‘n meerfasig vervormde en gemetamorfiseerde sedimentgesetelde onedel metaal afsetting in die sentrale Namakwa Provinsie van Suid Afrika. Die afsetting word geherberg deur die Boesmanland Groep, ‘n laat Paleoproterosoïse (2000 – 1600 Ma) bokors-opeenvolging van kwartsiet, metapelitiese skis en tussengelaagde metavulkaniese gesteente. Mineralisasie word gevind in the sentrale deel van die Gams Formasie. Die Gams Formasie is ‘n heterogene opeenvolging van gemetamorfiseerde metaalhoudende sediment en fynkorrelrige organiese skalie. Die erts horison word onderverdeel in ‘n onderste laag van metapeliet-gesetelde erts, n sentrale laag van fosforiet-gesetelde erts, en ‘n boonste laag van gebande granaat-apatiet erts. Die erts-liggaam word omhuls deur ongemineraliseerde silikaat-, karbonaat- en oksied-fasies metal-ryke rotse. Hierdie gesteentes word geinterpreteer as oorspronklike mengsels van Fe-Mn-ryke hidrotermale partikels, outigeniese karbonaat, en verskeie hoeveelhede detritale materiaal. Gebaseer op mineralogiese en geochemiese kenmerke word hierdie rotse onderverdeel in ysterformasies, „coticules“, Fe-Mn silikate, onsuiwer marmer en barite/Ba-ryke kwartsiet. Minerale van die Gams Formasie form meestal soliede oplossingsreekse tussen die Fe en Mn endlede van granaat, pirokseen, piroksenoid, amfibool, olivien, spinel en ilmeniet. Kalsium-ryke rots tipes is ‘n tipiese kenmerk van die Gams Formasie en word gekenmerk deur mangaan-ryke kalsiet, klinopirokseen, andradiet-ryke granaat en sfeen. Daar word ‘n stapsgewyse vergroting van die (Mn+Ca):Fe verhouding in gesteentes en minerale gevind met toeneemende afstand van die erts horison. Amfibool is beperk tot Fe-ryke ertsdraende gesteentes, ortopirokseen, klinopirokseen, Fe-ryke piroksenoid en olivien tot intermediêre gesteentes, en Mn-ryke rodoniet en piroksmangiet tot Mn-ryke gesteentes. Hierdie variasies gaan gepaard met vergroting van die Mn:Fe verhouding in granaat en ilmeniet-groep minerale met toeneemende afstand van die erts. LA-ICP-MS analises was gebruik om die skaars-aarde element patrone van granaat en apatiet te bepaal. In die erts-liggaam wys hierdie minerale ‘n positiewe Eu anomalie, wat geinterpreteerd word as ‘n hidrotermale kenmerk. In ongemineraliseerde gasheer gesteentes wys granaat en apatiet geen of ‘n negatiewe Eu anomalie. Primêre kenmerke van die Gams Formasie, soos skaars-aarde patrone, the gebande voorkoms van granaat-apatiet erts, die teenwoordigheid van diagenetiese apatiet knolle, en die verspreiding van die redox-sensitiewe elemente Ba en Mn, was gebruik om afleidings oor die paleo-omgewing te maak. Die resultate het gewys dat metapeliet-gesetelde erts afgeset was onder anoksiese bodem water deur presipitasie van Fe en Zn sulfiedes in organiese skalie. Hierdie erts gaan oor in fosforiet-gesetelde erts, granaat-apatiet erts en metaal-ryke gasheer gesteente wat in ‘n suboksiese tot oksiese omgewing ontstaan het. Die grootte van die afsetting, die interne gelaagdheid van die erts, asook die teenwoordigheid van sfaleriet en bariet dui op ‘n distale omgewing relatief tot die hidrotermale bron en presipitasie van die ertsuit digte en gereduseerde hidrotermale vloeistowwe, wat ontstaan het deur die heraktiveering van rustende groeiverskuiwings. Gesaamentlik bewys die geologiese kenmerke van Gamsberg dat gemetamorfiseerde SEDEX en Broken Hill-tipe mineralisasie binne die perke van ‘n enkele afsetting kan voorkom. Die geologiese verhoudings dui aan dat verskille tussen hierdie twee tipes van sedimentgesetelde afsettings meestal veroorsaak word deur omgewings-toestande binne in gelokaliseerde derde orde komme en nie deur fundamentele verskille in ertsvormende prosesse nie.
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Rex, Katja. "Diversity and resource partitioning in three assemblages of leaf nosed bats (Phyllostomidae: Chiroptera)." Berlin Logos, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=3060165&prov=M&dok_var=1&dok_ext=htm.
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Walz, Norbert. "Kritische Ethik der Natur ein pathozentrisch-existenzphilosophischer Beitrag zu den normativen Grundlagen der kritischen Theorie." Würzburg Königshausen und Neumann, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2889805&prov=M&dok_var=1&dok_ext=htm.
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Ochsenmeier, Erwin. "Mal, souffrance et justice de Dieu selon Romains 1 - 3 : étude exégétique et théologique /." Berlin [u.a.] : de Gruyter, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2998740&prov=M&dok_var=1&dok_ext=htm.
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Hoffmann, Andrea. "Innovative Lichttechnologie in der Automobilindustrie dargestellt am Beispiel eines LED-Scheinwerfers eine terminologische Untersuchung /." Trier : WVT, Wiss. Verl. Trier, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2977390&prov=M&dok_var=1&dok_ext=htm.
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Carré, Charlotte. "Rôle de la pollution par les métaux et de leur captage par un dépôt calco-magnésien formé en volume sur acier galvanisé en eau de mer." Thesis, Nouvelle Calédonie, 2017. http://portail-documentaire.unc.nc/files/public/bu/theses_unc/these_-_charlotte_carre1.pdf.
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Ce travail de recherche a pour objectif de détourner le processus bien connu de protection cathodique des structures métalliques maritimes contre la corrosion, pour en faire un outil efficace de décontamination des métaux polluant l’eau de mer. En effet, une des conséquence de cette protection est qu’elle conduit à la formation, sur le métal, d’un dépôt calcomagnésien, composé d'un mélange de brucite Mg(OH)2 et d'aragonite CaCO3, par précipitation des ions calcium et magnésium de l'eau de mer. L’idée est donc d’essayer de piéger dans ce dépôt des espèces métalliques polluantes.Dans un premier temps nous avons étudié la croissance du dépôt sur acier galvanisé en fonction du courant imposé et des paramètres physico-chimiques de l'eau. Si les variations du courant permettent de moduler la composition du dépôt (brucite/aragonite), l'agitation de l'eau et le temps de synthèse favorisent l'aragonite, et des températures élevées modifient les caractéristiques de la surface du dépôt.Par la suite, la capacité du dépôt à piéger pendant sa croissance du nickel et du plomb dissous dans l'eau a été étudiée en eau de mer synthétique. On démontre que l’efficacité du piégeage va dépendre du courant appliqué et que le nickel est piégé sous la forme Ni(OH)2, au contraire du plomb qui semble précipiter sous sa forme de carbonate. Ce piégeage semble rester partiellement pérenne, même en cas de rupture de la polarisation du métal. Finalement, des tests en milieu naturel dans une zone industrielle on permit de démontrer la pertinence de notre étude puisque en plus du Ni et du Pb, d’autres éléments tels Cr, Cu et Fe ont été piégésThe objective of this work is to divert the well-known cathodic protection process used to prevent metal structures against marine from corrosion, in order to develop an efficient tool for metal remediation in seawater. One of the consequences of this kind of protection is the formation of the calcareous deposit on the surface of the metal. The deposit is composed of a mixture of brucite Mg(OH)2 et aragonite CaCO3 and is formed by the precipitation of calcium and magnesium ions in seawater. The idea is to trap metallic pollutant in the calcareous deposit.First, the growth of the deposit has been studied on galvanized iron wires as a function of the impressed current and physical and chemical properties of the seawater. We found that variable values of the impressed current allow to control the proportion brucite/aragonite in the deposit. Increasing experiments duration and high water stirring speed favors the aragonite, and high temperatures modify the surface properties of the calcareous deposit.In the second part the nickel and lead trapping capacity of the deposit is studied in artificial seawater. We have demonstrated that the method works, and its efficiency depends on the impressed current. Material
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Anstett, T. F. "Grade-tonnage models of silver-copper-lead-zinc vein deposits of the Coeur d'Alene mining district, Idaho." 1986. http://catalog.hathitrust.org/api/volumes/oclc/14071286.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1986.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 145-148).
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Hawke, Michelle Irene. "Elemental characteristics of organic deposits from an area surrounding a lead-zinc smelter : concentration, distribution, mode of occurrence and mobility." Thesis, 2004. http://hdl.handle.net/2429/17082.
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Monitoring and remediation of anthropogenic trace elements requires knowledge of the magnitude of emissions and their fate in the environment. This study examines the role of organic sediments in the partitioning of Sb, As, Cd, Cu, Ni, Pb and Zn in the environment surrounding a lead-zinc smelter.
Trace element concentrations in peat profiles were highest near the smelter and decreased with distance. Peat concentrations were compared to mineral soil concentrations and to atmospheric deposition rates. Anomalies between peat concentrations and deposition rates identify locations of secondary source impact. Concentrations are higher in impacted peats than in corresponding soils, indicating preferential sequestration.
Assigning a geochemical baseline and differentiating between trace element sources is difficult in areas with heterogeneous geochemistry. Two geochemical fingerprinting methods were applied to estimate smelter impact: normalisation to "conservative elements" and rare earth element patterns.
Interpretation of "conservative element" ratios proved difficult, due to concentration variability. It was concluded that conservative elements may not represent a geochemical baseline.
Light rare earth element enrichment was noted in peats and other sampling media closest to the smelter, but not in smelter feedstock or wastes, suggesting that LREE enrichment is overprinted from background geochemistry.
Sources of trace element-rich particles include stack emissions and fugitive and geogenic dust. Peat ash was examined by SEM-EDX to determine the morphology and elemental composition of the particulates. Rounded smelter-emitted particles are present in peats sampled close to the smelter. Weathering and mobilisation are indicated by changes in chemistry between fresh and weathered particles. Angular fugitive dust sulphide particles also occur.
Sequential leaching of peats and soils illustrates that trace element speciation is controlled by environmental conditions and by source. In smelter-impacted peats, elements are sequestered as exchangeable, carbonate, Fe-oxide or organic species, indicating precipitation from solution. Non-impacted peats contain higher proportions of residual and sulphide species.
Environmental parameters impact peat diagenesis and influence element behaviour. An organic petrographic evaluation of smelter-impacted peats aids in determining past and current conditions. A well-humified profile, which indicates aerobic conditions, contained abundant Fe-oxide species. Profiles containing maceral assemblages that indicate anaerobic conditions contained sulphide and organic species.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Greyling, Lynette Natasha. "The paleoproterozoic carbonate-hosted Pering lead-zinc deposit, South Africa." Thesis, 2012. http://hdl.handle.net/10210/4283.
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M. Sc.The Pering Pb-Zn deposit is hosted in the stromatolitic dolomites of the Campbellrand Subgroup of the Ghaap Group, Transvaal Supergroup. The deposit is situated 20 km northeast of the town Reivilo in the semi-arid region of the Northwest Province, South Africa. It has been classified as a Mississippi Valley type deposit and is, together with the Bushy Park Pb-Zn deposit and F-Pb-Zn deposits near Zeerust, the only known MVT deposit of Paleoproterozoic age. The Pering open cast mine has been operational since 1986, yielding 18 Mt at an average ore grade of 3.6 wt.% Zn and 0.6 wt.% Pb. The aim of this study is to devise a metallogenetic model by integrating core logging, petrography, fluid inclusion and stable C-0-S isotope studies. The mineralogy includes sphalerite, galena and minor chalcopyrite as ore minerals, with diagenetic pyrite, hydrothermal dolomite, quartz and calcite as gangue minerals. Sphalerite predominates over galena. Mineralisation occurs as (a) disseminated stratabound replacements sheets restricted mainly to stromatolitic zones of the Steekdorings Member of the Reivilo Formation, and as (b) open space infill in breccia bodies that cross-cut the stratigraphy. Three events of hydrothermal brecciation, resultant of prolonged pulses of fluid infiltration, and mineralisation are recognised. The first brecciation event is marked by the cementation of the dolomite host rock by sparry dolomite, closely associated with finegrained disseminated sphalerite and galena. The second brecciation event is of minor importance, and is marked by the formation of small amounts of the second sphalerite generation, while the third, and final, brecciation event is marked by the formation of euhedral sphalerite, galena, quartz, sparry dolomite, and calcite as open space fill.
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Chang, Wan-Lan, and 常挽瀾. "Influence of the Lead Source Materials on the Microstructure and Ferroelectric Properties of PZT Films Magnetron Sputter-Deposited Using Lead and Lead Oxide." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/39367240617231655807.
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博士逢甲大學
材料科學所
93
A typical PZT (Pb(Zr0.54Ti0.46)O3) single target, a Pb/PZT dual target and a PbO/PZT dual target were used to deposit PZT films on a Pt/Ti/SiO2/Si substrate, to reveal the effects of the coating parameters of the three target configurations, on the microstructure and ferroelectric characteristics. The microscopic morphology and growth rate of the deposited PZT films was observed by FESEM, AFM and TEM. The crystal structure of the deposited PZT films was identified by XRD. The chemical state and chemical composition of the elements in the deposited films were determined by XPS and ICP, respectively. Ferroelectric polarization behavior, leakage current density, and the fatigue property of the deposited films were measured using a Radiant Technology RT66A tester. For the film deposited at the ambient temperature, the microscopic morphology was independent of the combination of targets, the smoothness of the surface and the featureless cross-section. The columnar grains of the PZT films deposited at substrate temperature of 580℃, were grown from the Pt/Ti/SiO2/Si bottom electrode layer with somewhat interdiffusion between deposited layer and substrate. The growth rate of the deposited films among three target configurations is great different and decreased as the increasing substrate temperature. The single PZT target, without lead compensation, presents a lowest growth rate over the entire range of substrate temperatures, while it is higher for Pb/PZT dual targets than that of the PbO/PZT dual targets due to the higher sputter yield of the Pb target than that of the PbO target. The deposited films consisted of perovskite phase with 15~20% excess lead can be obtained using a Pb/PZT dual target and a PbO/PZT dual target at a Pb and PbO target powers of over 25 W and 30W, respectively, at a substrate temperature of 580℃. However, deposition using a single PZT target over the range of substrate temperatures investigated was unsuccessful. The Pb/(Zr+Ti) decrease as the substrate temperature is increased at a fixed target power, but the Zr/(Zr+Ti) was independent of the deposition parameters. The surface of the deposited film is decomposed into PbOx, ZrOy and TiOz by reacting with the moisture in the atmosphere. Chemical states of the constituent elements of the deposited film deposited at a substrate temperature of 580℃ corresponds to be in form of perovskite phase structure either deposited by using Pb/PZT or PbO/PZT dual targets. The highest amount of perovskite phase presented in the film deposited using PbO/PZT dual target is found than that of the Pb/PZT dual targets and single PZT target. As a consequence, the P-E characteristics, the leakage current and the fatigue property of the films deposited using a PbO/PZT dual target are superior to those of films deposited using a Pb/PZT dual target, as ascribed to the excess lead, more oxygen vacancies and the less perovskite phase in the deposited film. Accordingly, perovsikte PZT thin film on Pt/Ti/SiO2/Si substrate can be successfully deposited both by using Pb/PZT and PbO/PZT dual target configurations in a RF magnetron sputtering system. The microstructure and chemical state of the deposited film are independent of the lead source materials though, the amount of excess lead, oxygen vacancies and PbOx/PZT strongly influence the P-E characteristics, the leakage current and the fatigue property of the PZT thin film, thereby provides useful information to whom involved in the sputter deposition of PZT thin films.
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Wallace, Sara Rose Bronwen. "The genesis of the Gayna River carbonate-hosted Zn-Pb deposit." 2009. http://hdl.handle.net/10048/408.
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Thesis (M. Sc.)--University of Alberta, 2009.Title from PDF file main screen (viewed on July 10, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Earth and Atmospheric Sciences, University of Alberta." Includes bibliographical references.
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Cheng, Wei-yuan, and 鄭惟元. "Chemical-vapor-deposited of lead based ferroelectric PZT films and its related research." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/05238944579046587314.
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博士國立臺灣科技大學
化學工程系
93
The aim of this study is placed on: (1) investigating the film-growth mechanism of PZT in the Pb(C2H5)4/Zr(O-t-C4H9)4/Ti(O-i-C3H7)4/O2-CVD system, (2) exploring the initial growth behavior of Ru (or RuOx) from the newly-developed Ru precursor, Ru(hfac)2(CO)2, for fabricating Ru-containing thin film as a electrode for PZT dielectric layer. In the first part, a cold-wall-typed CVD reactor was used to synthesize PZT thin film using Pb(C2H5)4, Zr(O-t-C4H9)4, Ti(O-i-C3H7)4 and O2 as the reactants. In the kinetic study of PZT film growth in this multi-component CVD system, it was found that a Langmuir-hinshelwood typed adsorption reaction with respect to Pb(C2H5)4 and O2 to form PbO dominates the PZT film growth. In contrast to the strong surface adsorption species, Pb(C2H5)4, two less adsorptive species, Ti(i-OC3H7)4 and Zr(t-OC4H9)4, were directly coming from the gas phase to react with PbO to form PZT films. That is, an Eley-Rideal growth mechanism dominates the PZT film growth in this multi-component CVD system. Moreover, in the initial growth study of PZT deposited on MgO(100) substrate by using XPS, AFM and EBSD techniques, it was found that the Stranski-Krastanov (SK) film growth model dominates the PZT formation that concerning a very thin layer of PbO (1 ~ 2 layers) first forms then PZT nucleates. In addition, a partial charge deviation was used to quantify the affinity of Pb(C2H5)4 on various oxide electrodes, and this explains well the PZT film growth dependency. In the second part, a newly-developed Ru precursor, Ru(hfac)2(CO)2, was used to investigate the initial growth behavior of Ru deposited on various surface terminations of Si(100) substrate. Furthermore, a quantum chemistry calculation for Ru(hfac)2(CO)2 was also employed to understand the surface reaction m
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方建瑋. "Fabrication of inverted lead halide perovskite hybrid organic solar cells with chemical bath deposited Zinc Oxide." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7rex9q.
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Lee, Yi-Lin, and 李億霖. "Effect of atomic layer deposited metal oxides on organic-inorganic hybrid lead halide perovskite solar cells." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/2gtjx2.
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碩士國立臺灣大學
材料科學與工程學研究所
106
Organic-inorganic hybrid lead halide perovskite solar cells have been developed rapidly because its excellent performance. However, the active material is unstable in ambient air, which limits its practical application. Thermal instability of devices states a more fundamental problem. In this thesis, atomic layer deposited inorganic metal oxides was applied to perovskite solar cells devices in order to solve the problem. We first investigated compatibility of perovskite with a variety of metallic precursors and with oxidants, respectively. We concluded criteria of selecting condition of ALD process and choice of precursors that would not damage perovskite. With optimal parameters, devices with ultra-thin atomic layer deposited Al2O3 or TiO2 direct on top of perovskite showed good performance. However, thermal instability of devices still did not improve due to imperfect coverage of oxides layer resulted from lack of nucleation cite on perovskite surface. To solve this problem, we deposited ALD AZO on organic charge transport layer instead. Device of this architecture reached efficiency of 14.6%, and only dropped to 80% of initial value after 1-day storage in glove box at 85℃. The thermal instability was much improved as efficiency of control devices dropped to less than 50% of initial value.
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Wang, Shih-Chieh, and 王士杰. "A Study of Lead Zirconate Titanate Pb(Zr0.52Ti0.48)O3 Thick Films Deposited by Aerosol Plasma Deposition Method." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/37163747950039600644.
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碩士國立臺北科技大學
材料及資源工程系碩士班
91
Recently, the application of piezoelectric thick film has been in intensively investigated for micro electro mechanical systems (MEMS) devices. This piezoelectric film was prepared by a novel method which combines aerosol deposition and low temperature plasma. We call this method as aerosol plasma deposition (APD). This method can grow piezoelectric thick films on Si wafers at relative low temperature. Lead Zirconate Titanate (PZT) films have been successfully grown by APD method at low temperature. This method is unique in its being capable of depositing coating at temperature lower than 200°C and at a deposition rate of several mm per minute. The PZT film grown by this technique had a relatively dense microstructure in SEM picture. The dielectric constant values were ranging from 180 to 300,with the dielectric loss factor in the range of 2.9~5.1 % was demonstrated. The phase of the as-deposited film examined by XRD was PZT perovskite phase. However, some second phase (pyrochlore) and amorphous phase can be detected by high-resolution TEM. As the result, the dielectric constant and dielectric loss can be improved to be 650~760 and 2.5~4.8% after heat treatment at 600oC and 1hour. The remnant polarization of 17.6 μC/cm2 and the coercive field of 67 KV/cm was obtained.
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Wen-MingChen and 陳文明. "Study of Molten Lead-free Solder Deposited by Inkjet Printing for Bonding of Thin-film Solar Cell Modules." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/45848479773543162118.
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碩士國立成功大學
材料科學及工程學系碩博士班
101
The photovoltaic industry is fast growing and the fabrication of solar cells has been kept improving. Nowadays, the main type of solar cell development is thin-film solar cells. However, most of studies focus on the solar cell structure to enhance the photovoltaic conversion efficiency rather than improving the solar module packaging process. For module packaging process, the bus wire bonding and the encapsulation of solar cells are needed in the fabrication of thin-film solar cell. In order to keep stable photovoltaic conversion efficiency after module packaging, good bonding strength is required between copper ribbon and aluminum back electrode of thin-film solar cell. Inkjet printing technology is a non-contact direct fabrication process, which can control precise droplet size and position and reduce material consumption. This study used lead-free solder as bonding material by inkjet printing process and module packaging technology for getting better quality of solar cell modules. In this study, Sn3.0Ag0.5Cu solders were successfully printed by using inkjet printing technology for bonding of thin-film solar cell modules. The results show that the peel strength of lead-free solder is better than that of silver paste when the dot spacing of lead-free droplets is lower than 200 μm. In other words, the amount of lead-free solder is over than 50 μg/mm2. As the bonding strength increases, the efficiency loss decreases. The optimum results of low efficiency loss degrade 1.5 % and good photovoltaic conversion efficiency is over 8.3 %.
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Yang, Chia-Huei, and 楊家慧. "Synthesis and Characterization of Lead Iodide Semiconducting Film Deposited on Rh(100) and Rh(111) single crystal electrodes." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/21696671426527707384.
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碩士國立中央大學
化學研究所
90
Adsorption of iodine atoms from a vapor phase onto an annealed Rh(100) single crystal produced either a well-ordered monolayer or multiple layers iodine, depending on the dosing levels. High-quality scanning tunneling microscopy (STM) atomic resolutions of these iodine adlayers were achieved, rendering the characterization of a (√2 × √2)R45° - I structure for the monolayer case and two different structures for the multiple layer cases. These iodine adlayers served as the substrates onto which PbI2 films were deposited from aqueous solutions of Pb(NO3)2 with KI mixed in the presence of excess amount of acetonitrile. X-ray photoelectron spectroscopy results also indicate the presence of stoichiometric amounts of Pb2+ and I- ions at the surface of Rh(100). STM imaging of these PbI2 films in air revealed a hexagonal array with a lattice constant of 0.45 nm, consistent with the ideal value of PbI2 crystal. The strong van der Waals interactions between the iodine overlayer and one of the iodide layers of PbI2 are responsible for the deposition of PbI2 on the surface. STM tentatively discerned the atomic arrangements of the uppermost iodide layer of PbI2.
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Zuna, Milan. "Dřevní letokruhy a rašeliny jako archívy recentních trendů depozice Pb a Hg v České republice." Doctoral thesis, 2012. http://www.nusl.cz/ntk/nusl-305936.
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1 Tree rings and peat bogs as archives of recent trends in Pb and Hg deposition in the Czech Republic Milan Zuna, 2012 Abstract The environment polluted by toxic metals is currently one of the most topical subjects studied in a great many countries. Toxic metals and their forms are studied primarily because of their negative impact on the environment and also on human health. In the territory of the Czech Republic, direct measurements of the concentrations of these substances are available only for a limited time period. Consequently, indirect methods, such as geochemical archives, are used to determine the historical environmental burdens from these metals. Historical lead concentrations (Pb) were studied on peat bog profiles and tree rings in selected localities in the Czech Republic. Altogether 12 peat bog profiles and 33 wood cores (Picea abies) were studied, in the border territories of the Czech Republic with different historical burdens (Krušné Hory - Novodomské rašeliniště - ND, Jizerské hory - Bílá Smědá - BS, Šumava - Jezerní slat - JS), and in a historically burdened area polluted by processing of Pb- Ag ores (Příbram-Brdy). In the vicinity of Příbram, areas around the Brdy ridge (9 km east of the Pb metallurgical works) as well as in the immediate vicinity of the metallurgical works. We used the...
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Chiu, Chun-Wei, and 邱俊暐. "Studies on interfacial reactions of lead-free solder joints and electroless deposited diffusion barriers in the Bi2Te3-based thermoelectric system." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/632yph.
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碩士國立中正大學
化學工程研究所
102
Thermoelectric (TE) devices consist of many pairs of p- and n-type semiconductor elements, which are interconnected electrically by soldering technology. Bi2Te3-based alloys are the most popular thermoelectric materials. Sb and Se are usually alloyed to Bi2Te3-based alloys for p- and n-type, respectively, i.e., Bi0.5Sb1.5Te3 and Bi2Te2.7Se0.3. Ni is frequently used as a diffusion barrier to prevent the fast IMC growth. In this research, we studied the solid/solid and liquid/solid reactions between Sn-based solders (Sn or Sn-58Bi) and Bi2Te3-based thermoelectric materials. The SnTe growth rate of p-type couples were larger than the n-type. For the liquid-state aging, Sn reacted with TE substrates with two different directions (⊥c-axis or //c-axis), we found that the IMC growth of the Sn/p-type substrate reaction couple was anisotropic. The growth kinetics were also investigated. For the solid-state reactions, the growth is parabolic for p- and n-type reactions. For the liquid-state reactions, the growth of the p-type reaction is linear, and the n-type case followed a parabolic law. This study also simulated the solder joints of the thermoelectric device, using the electroless deposition of Ni-P or Co-P as a diffusion barrier between Sn and TE substrates. In the Ni-P system, the reaction was inhibited significantly between solder and p-type material. For the n-type cases, Sn diffused through the Ni-Sn-P layer when the Ni-P barrier was depleted, the NiTe phase occurred phase transformation in substrate side, and the SnTe and BiTe phases were formed. During the liquid reaction, the Ni-P layer was peeled off from the interface due to thermal expansion stress, resulting in the fast IMC formation. For the Co-P cases, Sn fast reacted with the Co-P layer and formed the CoSn4 phase. After an aging period of the p-type reaction, the metastable CoSn4 phase was transformed to Co(Sn,Sb)3 phases and the SnTe was formed in substrate side. In the solid/solid reaction of n-type, the CoSn4/Co-Sn-P/SnTe/BiTe structure was found. Both the p- and n-type liquid/solid reactions, the CoSn4 and Co-Sn-P phases were formed, and massive spallation of the CoSn4 phase occurred. In addition, the electroless Co-W-P was deposited on Cu substrate, and reacted separately with Sn or SAC305. The layer-structured CoSn3 phase and Co-Sn-P IMC were formed at the interface between Sn and the Co-W-P layer, while the (Cu,Co)6Sn5/CoSn3/Co-Sn-P structure was observed for using the SAC305 solder. In the liquid-state reactions, the Co-Sn and Co-Sn-P phases were formed in the initial stage. With the reaction proceeding, the Co-Sn phase was spalled into the liquid-state solder. When the Co-W-P was depleted, Cu fast diffused into the solder and the Co-Sn spalling phase transformed into (Cu,Co)6Sn5. The Co-Sn-P ternary phase grew thicker obviously, and a thick porous-structured Cu6Sn5 phase was formed at the interface. Finally, the Co-Sn-P layer was peeled off and the Cu6Sn5 thickness grew significantly.
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LIN, CHE-YANG, and 林哲揚. "A study on interfacial reactions in lead-free solder joints-using co-deposited Co(P) and Co(Zn) as diffusion barrier." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/58371526988694472883.
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碩士國立中正大學
化學工程研究所
105
Co system is the most promising diffusion barrier on the electronic package, but the interfacial reaction between Co and Sn was extremely fast, which led to the massive Sn-Co IMC growth, so that the reliability of the solder joint is reduced. In our past studies, we prepared Co-0.7wt.%P diffusion barrier by electroless plating, that showed great inhibition of Sn-Co IMC growth. Besides, Sn solder with minor Zn addition also had very good inhibition between Sn/Co interfacial reactions. But electroless plating method had higher processing temperature (90oC) and slow deposition rate, that make it difficult to be applied to electronic packaging process. However, the electroplating process had lower processing temperature(55oC) and the deposition rate was relatively fast, that make it suitable for electronic packaging. In this study, we used a simple and convenient electroplating method to deposit Co(P) or Co(Zn) diffusion barrier, by adding NaH2PO2∙H2O or ZnSO4∙7H2O into commercial Co plating bath. The P or Zn element was then co-deposited with the Co on the substrate during plating process. This study investigate whether the P or Zn element had great inhibition on the Sn-Co interfacial reaction, and compared the results with Sn/Co/Cu system. The Co(P) and Co(Zn) exhibited columnar structures was observed in FIB cross-sections. In Co(P) system, the prefer orientation of Co showed Co(0 0 2) in XRD, and Co(1 0 0) in GIXRD. In Co(Zn) system, with the increase of Zn from 0.56wt.% to 8.78wt.%, the prefer orientation in XRD changed from Co(1 1 0) to Co(0 0 2). However, in GIXRD, the prefer orientation were Co(0 0 2), indicating that with the addition of P and Zn would affect the crystal growth of Co. In the results of Co(Zn) heat treatment, several fine grains were observed in FIB cross-sections, and a broad peak appeared in XRD analysis showed the existence of 1-CoZn7 phase. The formed IMC in Sn/Co(P)/Cu system and Sn/Co(Zn)/Cu system were analyzed by EPMA and XRD. Both CoSn3 and CoSn4 were identified, and ternary Co-Sn-P phase were formed in Sn/Co-2.5wt.%P/Cu and Sn/Co-3.0wt.%P/Cu system. The growth of the IMCs showed great inhibition from Co-0.5wt.%P to Co-2.0wt.%P, it retarded about 88%、93.7% and 94% of IMC growth. For Co-2.55wt.%Zn and Co-6.77wt.%Zn system, it retarded about 88% and 98% of IMC growth. To discuss the inhibition behavior of the IMC growth, in the results of EPMA analysis, the existence of P and Zn in Sn-Co IMC in Sn/Co(P)/Cu and Sn/Co(Zn)/Cu system were identified. It is inferred that the P element doped into the lattice of the Sn-Co IMC, so it was hard for Sn atoms to diffuse, cause the inhibition of IMC growth. In the Co (Zn) system, the 1-CoZn7 phase precipitated in Co(Zn) during reaction, and a sufficient amount of Zn element can doped into the lattice of Sn-Co IMC, so that the growth of IMC were inhibited.
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Islam, Samia. "Validate a method for the determination of Cadmium and Lead by using Stripping Chronopotentiometry (SCP) obtained by thin mercury film deposited on rotating disk electrode (TMF-RDE)." Master's thesis, 2012. http://hdl.handle.net/10400.1/10623.
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Dissertação de Mestrado, Qualidade em Análises, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2012Neste trabalho, um novo método foi desenvolvido e validado para a determinação de Cd e Pb em água da torneira, com base num eléctrodo de disco rotativo (RDE-TMF), utilizando cronopotenciometria de redissolução (SCP). A espessura do TMFE foi determinada foi (1,46 ± 0,06) x 10-3 C para um intervalo de confiança de 95%. O procedimento foi composto por: potencial de deposição - 0,78 V; tempo de deposição 90 s; corrente de redissolução 5 μA e agitação de 1500 rpm. Para ambos os metais, a linearidade obtida dentro do intervalo de concentração de (2,5 × 10-9 a 1 × 10-7 M) percentagens de recuperação de foram 111 ± 15% e 103 ± 11% foram obtidos para o cádmio e para o chumbo, respectivamente (com base nos resultados dos materiais de referência certificados). Os limites de detecção obtidos para o Cd e Pb foram de (4,7 ± 3,8) x 10-10 M e (3,2 ± 0,4) x 10-10 M, respectivamente, e foram também obtidos valores de CV < 8%. O método analítico SCP revelou-se eficaz para a determinação de cádmio e chumbo na água da torneira utilizando o filme fino de mercúrio depositado sob um eléctrodo de disco rotativo.
A new validated method for Cd and Pb determinations in tap water, based on rotating disk electrode (TMF-RDE), using stripping chronopotentiometry (SCP), was developed. The TMFE thickness determined was determined at (1.46 ± 0.06) × 10-3 C for 95% confidence interval. The procedure comprised: deposition potential - 0.78 V; deposition time 90 s; stripping current 5 μA and stirring rate 1500 rpm. For both metals linearity was achieved within the concentration range of (2.5 × 10-9 to 1 × 10-7 M) with a high value of the regression coefficient based on the results of the Certified Reference Materials the trueness values in terms of % recovery were found to be 111 ± 15 % and 103 ± 11 % for cadmium and lead respectively. Detection limits of (4.7 ± 3.8) × 10-10 M and (3.2 ± 0.4) × 10-10 M were obtained for Cd and Pb, respectively, and CV values < 8% were observed. SCP was found to be an effective method for cadmium and lead in tap water by using thin mercury film on rotating disk electrode.
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Yuen-Nan, Chiu. "Electrical Property and Material Analysis of GaN MOS Diode and Investigation of Fe3Si Deposited on LED by Molecular Beam Epitaxy." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0016-1303200709303068.
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