Дисертації: "Gold distribution"

1

Aylmore, Mark G. "Distribution and agglomeration of gold in arsenopyrite and pyrite." Thesis, Curtin University, 1995. http://hdl.handle.net/20.500.11937/149.

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The form and location of gold in the structure of arsenopyrite and pyrite minerals, and the mechanisms for the mobility agglomeration of gold in arsenopyrite during thermal treatment, have been studied using a combination of Rietveld X-ray diffraction refinement, Convergent Beam Electron Diffraction (CBED) and Atomic Location by Channelling Enhanced Microanalysis. The basic structure of all the arsenopyrite compositions studies, has been shown to be monoclinic P2(subscript)1/c, regardless of the variation in stoichiometry. An increase in the arsenic to sulfur ratio in the natural arsenopyrites was found to be associated with an increase in unit cell dimensions accompanied by expansions within the iron-centred octahedra along the [101] direction of the monoclinic cell and concommitant contractions of the octahedra in the (101) plane. There was no obvious relationship between variation in stoichiometry and structure of arsenopyrite which could provide information as to possible substitution of gold in its structure. However, atomic displacements caused by twinning or disorder, may help to incorporate gold.The synthesis of auriferous arsenopyrites showed that gold has to be in an ionic form to be taken up in the structure. The form of the gold species affects the distribution of gold in the structure, being chemically zoned when derived from a dichloro complex and more evenly distributed when derived from a hydrosulfido complex. It is suggested that rapid crystallisation, with resultant displacement faults along the b-axis, may contribute to higher concentrations of gold in the natural arsenopyrite structure. Electron probe microanalysis showed a possible slight iron-deficiency in some of the auriferous arsenopyrite grains analysed. However, the errors in the analyses were too high to provide conclusive evidence of gold substitution in the iron sites, as has been proposed in the literature.Analyses of natural and synthetic pyrites showed no deviations in structural parameters which could indicate possible substitution of gold or other impurities within the structure.Electron channelling experiments showed that gold was located on the sulfur sites in pyrite. In arsenopyrite, there was some evidence for gold located on the iron sites, however, most gold was interstitial, probably situated between the octahedra. This location is probably facilitated by the presence of the displacement faults as observed by CBED in the synthetic auriferous arsenopyrite.Breakdown of arsenopyrite under thermal treatment was topotactic along its b-axis, which converts to the a-axis in the pyrrhotite structure, following a reconstruction mechanism based on the preferential removal of arsenic over sulfur. Gold was visually recorded exsolving from the arsenopyrite structure and agglomerating as liquid metal globules as the arsenopyrite was chemically altered during thermal treatment under the Transmission Electron Microscopy electron beam. Gold became mobile on the decomposition of arsenopyrite, but this was not observed until a temperature of approximately 470 degrees celsius was reached. Above the temperature both solid solution and particulate gold became mobile. The interaction of arsenic vapour and gold reduced the melting point of gold.The observations on the effects of arsenic residence time, and the relative mobility of solid solution and particulate gold during the thermal decomposition of auriferous arsenopyrite and pyrite, have significant implications for improved industrial extraction of gold from these minerals.

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2

Aylmore, Mark G. "Distribution and agglomeration of gold in arsenopyrite and pyrite." Curtin University of Technology, School of Applied Chemistry, 1995. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=11407.

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The form and location of gold in the structure of arsenopyrite and pyrite minerals, and the mechanisms for the mobility agglomeration of gold in arsenopyrite during thermal treatment, have been studied using a combination of Rietveld X-ray diffraction refinement, Convergent Beam Electron Diffraction (CBED) and Atomic Location by Channelling Enhanced Microanalysis. The basic structure of all the arsenopyrite compositions studies, has been shown to be monoclinic P2(subscript)1/c, regardless of the variation in stoichiometry. An increase in the arsenic to sulfur ratio in the natural arsenopyrites was found to be associated with an increase in unit cell dimensions accompanied by expansions within the iron-centred octahedra along the [101] direction of the monoclinic cell and concommitant contractions of the octahedra in the (101) plane. There was no obvious relationship between variation in stoichiometry and structure of arsenopyrite which could provide information as to possible substitution of gold in its structure. However, atomic displacements caused by twinning or disorder, may help to incorporate gold.The synthesis of auriferous arsenopyrites showed that gold has to be in an ionic form to be taken up in the structure. The form of the gold species affects the distribution of gold in the structure, being chemically zoned when derived from a dichloro complex and more evenly distributed when derived from a hydrosulfido complex. It is suggested that rapid crystallisation, with resultant displacement faults along the b-axis, may contribute to higher concentrations of gold in the natural arsenopyrite structure. Electron probe microanalysis showed a possible slight iron-deficiency in some of the auriferous arsenopyrite grains analysed. However, the errors in the analyses were too high to provide conclusive evidence of gold substitution in the iron sites, as has been ++
proposed in the literature.Analyses of natural and synthetic pyrites showed no deviations in structural parameters which could indicate possible substitution of gold or other impurities within the structure.Electron channelling experiments showed that gold was located on the sulfur sites in pyrite. In arsenopyrite, there was some evidence for gold located on the iron sites, however, most gold was interstitial, probably situated between the octahedra. This location is probably facilitated by the presence of the displacement faults as observed by CBED in the synthetic auriferous arsenopyrite.Breakdown of arsenopyrite under thermal treatment was topotactic along its b-axis, which converts to the a-axis in the pyrrhotite structure, following a reconstruction mechanism based on the preferential removal of arsenic over sulfur. Gold was visually recorded exsolving from the arsenopyrite structure and agglomerating as liquid metal globules as the arsenopyrite was chemically altered during thermal treatment under the Transmission Electron Microscopy electron beam. Gold became mobile on the decomposition of arsenopyrite, but this was not observed until a temperature of approximately 470 degrees celsius was reached. Above the temperature both solid solution and particulate gold became mobile. The interaction of arsenic vapour and gold reduced the melting point of gold.The observations on the effects of arsenic residence time, and the relative mobility of solid solution and particulate gold during the thermal decomposition of auriferous arsenopyrite and pyrite, have significant implications for improved industrial extraction of gold from these minerals.

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3

Manohar, Nivedh Harshan. "Quantitative imaging of gold nanoparticle distribution for preclinical studies of gold nanoparticle-aided radiation therapy." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54877.

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Gold nanoparticles (GNPs) have recently attracted considerable interest for use in radiation therapy due to their unique physical and biological properties. Of interest, GNPs (and other high-atomic-number materials) have been used to enhance radiation dose in tumors by taking advantage of increased photoelectric absorption. This physical phenomenon is well-understood on a macroscopic scale. However, biological outcomes often depend on the intratumoral and even intracellular distribution of GNPs, among other factors. Therefore, there exists a need to precisely visualize and accurately quantify GNP distributions. By virtue of the photoelectric effect, x-ray fluorescence (XRF) photons (characteristic x-rays) from gold can be induced and detected, not only allowing the distribution of GNPs within biological samples to be determined but also providing a unique molecular imaging option in conjunction with bioconjugated GNPs. This work proposes the use of this imaging modality, known as XRF imaging, to develop experimental imaging techniques for detecting and quantifying sparse distributions of GNPs in preclinical settings, such as within small-animal-sized objects, tissue samples, and superficial tumors. By imaging realistic GNP distributions, computational methods can then be used to understand radiation dose enhancement on an intratumoral scale and perhaps even down to the nanoscopic, subcellular realm, elucidating observed biological outcomes (e.g., radiosensitization of tumors) from the bottom-up. Ultimately, this work will result in experimental and computational tools for developing a better understanding of GNP-mediated dose enhancement and associated radiosensitization within the scope of GNP-aided radiation therapy.

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4

Polito, Paul A. "Exploration implications predicted by the distribution of carbon-oxygen-hydrogen gases above and within the Junction gold deposit, Kambalda, Western Australia /." Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09php769.pdf.

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5

Coxon, Brian Duncan. "Lateritisation and secondary gold distribution with particular reference to Western Australia." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005586.

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Lateritisation is associated with tropical climates and geomorphic conditions of peneplanation where hydromorphic processes of weathering predominate. Laterites are products of relative (residual) and absolute(chemical) accumulation after leaching of mobile constituents. Their major element chemistry is controlled by the aluminous character of bedrock and drainage. Bauxitisation is characterised by residual gibbsite neoformation and lateritisation, by both residual accumulation and hydromorphic precipitation of goethite controlled by the redox front at the water table. The laterite forms part of a weathering profile that is underlain by saprock, saprolite, the mottled zone and overlain by a soil horizon. The secondary gold in laterites has its source invariably with mineralised bedrock. The distribution of secondary gold is controlled by mechanical eluviation and hydromorphic processes governed by organic, thiosulphate and chloride complexing. The precipitation of secondary gold is controlled by pH conditions, stability of the complexing agent and ferrolysis. Gold-bearing laterites are Cainozoic in age and are best developed on stable Archean and Proterozoic cratons that have suffered epeirogenesis since lateritisation. Mechanical eluviation increases in influence at the expense of hydromorphic processes as a positive function of topographic slope and degradation rate. Gradients greater than 10⁰ are not conducive for lateritisation, with latosols forming instead. High vertical degradation rates may lead to the development of stone lines. In the Western Australian case, post-laterite aridification has controlled the redistribution of secondary gold at levels marked by stabilisation of the receding palaeowater table. Mineable reserves of lateritic ore are located at Boddington, Westonia and Gibson toward the south-west of the Yilgarn Block. A significant controlling variable appears to be the concentration of chloride in the regolith. Based on the Boddington model, the laterite concentrates the following elements from bedrock gold lodes: i) Mo, Sb, W, Hg, Bi and Au as mobile constituents. ii) As and Pb as immobile constituents. Geochemical sampling of ferruginous lag after bedrock and laterite has provided dispersed anomalies that are easily identifiable. "Chalcophile corridors" up to 150 km in length are defined broadly by As and Sb but contain more discrete anomalies of Bi, Mo, Ag, Sn, W, Se or Au, in the Yilgarn Block. The nature of the weathered bedrock, the tabular distribution of secondary gold ore deposition and the infrastructural environment lends the lateritic regolith to low cost, open-cut mining. The western Australian lateritic-gold model perhaps can be adapted and modified for use elsewhere in the world.

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6

Sibbick, Steven John Norman. "The distribution and behaviour of gold in soils in the vicinity of gold mineralization, Nickel Plate mine, southern British Columbia." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28862.

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Sampling of soils and till are conventional methods of gold exploration in glaciated regions. However, the exact nature of the residence sites and behaviour of gold within soil and till are poorly known. A gold dispersion train extending from the Nickel Plate mine, Hedley, southwest British Columbia, was investigated in order to determine the distribution and behaviour of gold within soils developed from till. Three hundred and twelve soil, till and humus samples (representing LFH, A, B and C horizons) were collected from fifty-two soil pits and thirty-four roadcut locations within the dispersion train. Soil and till samples were sieved into four size fractions; the resultant -212 micron (-70 mesh) fraction of each sample was analysed for Au by FA-AAS. Humus samples were ground to -100 micron powder and analysed for Au by INAA. Based on the analytical results, each LFH, A, B and C horizon was subdivided into anomalous and background populations. Detailed size and density fraction analysis was carried out on soil profiles reflecting anomalous and background populations, and a mixed group of samples representing the overlap between both populations. Samples were sieved to six size fractions; three of the size fractions (-420+212, -212+106, -106+53 microns) were separated into two density fractions using methylene iodide and analysed for Au by FA-AAS. The Au content of the -53 micron fraction was analysed by FA-AAS and cyanide extraction - AAS. Results indicate that the Au content of soil profiles increase with depth while decreasing with distance from the minesite. Heavy mineral concentrates and the light mineral fraction Au abundances reveal that dilution by a factor of 3.5 occurs within the till over a distance of 800 metres. However, free gold within the heavy mineral fraction is both diluted and comminuted with distance. Recombination of size and density fractions indicate that the Au contents of each size fraction are equivalent; variation in Au abundance is not observed with a change in grain size. Seventy percent of the Au in the -53 micron fraction occurs as free gold. Chemical activity has not altered the composition of gold grains within the soil profiles. Compositional and morphological differences between gold grains are not indicative of glacial transport distance or location within the soil profile. Relative abundances of gold grains between sample locations can be used as an indicator of proximity to the minesite. The sampling medium with the best sample representivity and contrast between anomalous and background populations is the -53 micron (-270 mesh) fraction of the C horizon. Geochemical soil sampling programs in the vicinity of the Nickel Plate mine should collect a minimum mass of 370 grams of -2000 micron (-2 mm) soil fraction in order to obtain 30 grams of the -53 micron fraction.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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7

Slabbert, W. L. "Ore distribution controls of the Navachab Gold Mine, Damara Belt, Karibib District, Namibia." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1016364.

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The Navachab Gold mine, an orogenic lode gold deposit, is located in the Karibib region of the Pan-African (ca. 550-500) Damara belt of central Namibia. Gold mineralisation is developed within the steeply NW dipping limb of the Karibib dome. Here, ore envelopes trend along three main orientations: a) trends shallowly towards the NE (the down plunge extent), b) trends sub-vertically in and along the down plunge extent and c) trends sub-horizontally across the down plunge extent. The down plunge extent represents the bulk of the gold mineralisation, hosting the only high grade ores mined at Navachab. As such, past work primarily focused on establishing the controls to the mineralisation observed here. The sub-vertical and sub–horizontal ore trends are seen as secondary, lower grade, being hosted in the footwall. By cutting pushbacks into the footwall, in an effort to regain access to high grade pit bottom, future gold production almost exclusively relies upon optimally mining these ores. This underlines the importance to investigate and outline the mineralising controls to the secondary ore trends. This study identified the following prevailing quartz vein sets developed within the footwall, set (1) dips shallowly towards the NE (conjugate vein set), (2) steeply towards the NW (bedding parallel veins) and (3) steeply towards the SE (S2 foliation parallel). The NW and SE dipping sets contain high average gold grades, occurring at an infrequent vein density. The NE dipping veins, as a result of occurrence density alone, was highlighted as the dominant gold hosting set. Veining occurred during the late stages of the NW-SE directed, sub-horizontal shortening (D2) event and is associated with top-to-the-NW thrusting and NW-verging folds. Re-Os molybdenite dating from auriferous quartz veins indicates mineralisation occurred at 525-520 Ma. As crustal shortening amplified the Karibib dome, flexural flow developed fractures along bedding planes, providing the control to bedding parallel veins (NW dipping). With continued crustal compression the dome later experienced fold lock up associated with reduced mean rock stress and sub-horizontal extension occurred along the steeply NW dipping limb. Horizontal extensional gashes sucked in fluids to form the shallowly NE dipping conjugate vein set. These features suggest the regional D2 strain as the first-order control to quartz vein development, down plunge and within the footwall ores. To further define the secondary ores, lithological and structural controls were evaluated on a more detailed local scale. With equal amounts of biotite schist and calc-silicate host rock (bulk of the footwall lithology) material analysed, the biotite schist units were found to contain a larger volume amount of quartz veins. The mineralisation incurred is also developed at higher average gold grades compared to that of the calc-silicates, demonstrating biotite schist having the optimal rheology for quartz vein emplacement. Normal faulting and thrusting occurs widespread, at all scale levels, across the footwall. These were primarily observed along bedding foliations and secondly at higher angles cutting across foliation. The study did not constrain the extent of these, but can conclude faulting plays a very prominent role in re-distributing the secondary ores parallel to bedding along sub-vertical trend planes. Great care should be placed in properly modelling these with 3D software such as Leapfrog. The Navachab gold mineralisation came about as a result of convergent and collisional tectonics activating metamorphic dehydration of the crustal metapelites. As these fluids ascended they absorbed gold from the crust, emplaced by either a magmatic or paleo-placer source. The gold enriched hydrothermal fluids amalgamated in large scale 1ste order structures (shearing of the steep NW limb of the Karibib Dome, the Mon Repos Thrust Zone) that acted as primary active fluid path ways. In the case of Navachab the gold enriched fluid fluxed along these pathways while interacting with fluid sinks related to a physical throttle (brittle schist, folding, bedding parallel shears) and/or a chemical trap (marbles). By summarising and detailing the fluid sinks and active fluid pathways identified by this and previous works, it is strongly recommended that a mineral approach system be designed and implemented as targeting model to lead future exploration endeavours.

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8

Armitage, Michael Graham. "The occurrence and distribution of gold in shear zones at Renco Mine, Zimbabwe." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281878.

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9

Sener, A. K. "Characteristics, distribution and timing of gold mineralisation in the Pine Creek Orogen, Northern Territory, Australia /." Connect to this title, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0102.

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10

Wedin, Francis. "Controls on the characteristics, timing and distribution of epithermal gold deposits in western Turkey." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/46336/.

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A study of epithermal gold mineralisation has been conducted across the Western Anatolian Volcanogenic and Extensional Zone (WAVE) in western Turkey. A Bulk Leach Extractable Gold stream sediment survey was undertaken, in addition to rockchip sampling and analysis of drill core, and mapping. Clay samples from the Simav Fault were dated, geophysical data over the study area analysed, and new GIS data was examined. Hitherto unknown epithermal gold deposits –including Akçapınar, Kőprűbaşı and Yaylabayır - have been discovered during the progress of this largely field based study, as well as a north-east striking gold deposit belt, named the Kozak Gold Corridor. Kőprűbaşı is among a number of jasperoid-hosted deposits which represent a new deposit analogue in WAVE, termed “Demirci-Type”. This research has produced a new geological model for the formation of epithermal gold deposits in the WAVE Zone. The model links a south-west migration of the subduction zone in WAVE during the Miocene with similar patterns of gold deposition, with the latter occurring in at least one distinct episode between 19 and 23Ma. Dacitic to rhyolitic volcanics acted as highly favourable host rocks for gold deposition, while ophiolitic mélange and Pan-African schist rocks are shown to provide a secondary crustal enrichment of gold, and the main structural controls are observed to be east-west P shears and north west-south east R1 shears. The Simav Fault is shown to be mineralised and a crucial deep conduit for gold deposits in its hangingwall. Tilting of graben and half-graben blocks in WAVE accounts for different degrees of uplift and erosion between deposits of similar age, such as Kızılçukur and Kızıltepe. Future gold exploration in the region should be focussed on targeting similar parameters to this model. The Kozak Gold Corridor and Sındırgı Gold Corridor are deemed prospective for further discoveries.

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11

Barbosa, Leo. "EXAMINATION OF MICRO-SCALE SULFIDE DISTRIBUTION FOR THE GOLD MINERALIZATION IN THE LAPPBERGET DEPOSIT, GARPENBERG MINE, SWEDEN: TOWARDS A GEOMETALLURGICAL APPROACH." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-87022.

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Ore characterization studies are of great importance to the mining industry, especially when dealing with precious metals by-products. It is a way towards increasing mining efficiency. The Swedish Boliden’s Zn–Pb–Ag–(Cu–Au) Lappberget Deposit is the main ore body at the Garpenberg Mine producing concentrates of zinc, lead, copper, and a gravity concentrate of silver and gold, which accounts for a significant revenue for the mine. Garpenberg Mine is an ancient and traditional mining site in Sweden, nonetheless the Lappberget deposit is a relatively recent discovery and there are still on-going studies on this ore body. More recently detailed ore investigations have been carried out on the sulfides and silver mineralization in different geological domains within the Lappberget deposit. In this context, the present work is focused on investigating the gold mineralization of the deposit, aiming to study the occurrence and distribution of gold minerals, characterize the gold in the ore and how its characteristics affect gold recoveries during its processing. To achieve these goals, different investigative methods were applied on drill core samples of the footwall disseminated to semi-massive mineralization (FWD), and on samples from the gravity concentrator at Boliden’s processing plant. The techniques applied were optical microscopy, scanning electron microscopy, energy dispersive x-ray spectrometry, electron probe microanalysis, laser ablation inductively couple plasma mass spectrometry, and bulk chemical analysis. The main findings pointed electrum as the main gold mineral, occurring with a strong sulfide association, in a variety of textures and grain sizes. The study also identified the occurrence of Au-Bi alloy, not previously described in literature of the Garpenberg region. The potential of invisible gold in the sulfide carriers was also a subject of investigation, as well as the evaluation of the characteristics of the samples from the gravity concentrator.

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12

Côté, Carol. "La distribution de l'or à la mine Montauban /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1989. http://theses.uqac.ca.

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13

Sener, A. K. "Characteristics, distribution and timing of gold mineralisation in the Pine Creek Orogen, Northern Territory, Australia." University of Western Australia. Centre for Global Metallogeny, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0102.

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Over the last two decades, gold occurrences in the Palaeoproterozoic Pine Creek Orogen (PCO) have been cited as type-examples of high-temperature contact-metamorphic or thermal-aureole deposits associated with granitoid magmatism. Furthermore, spatial relationships between these gold occurrences and the granitoids have led to inclusion of these deposits in the intrusion-related gold deposit group. Research on the characteristics, distribution and timing of these gold deposits tests these classifications and supports an alternative interpretation. The deposits display many similarities to well-described ‘turbidite-hosted’ orogenic gold deposits described from several Palaeozoic orogens. As in most ‘turbidite-hosted’ orogenic deposits, the gold mineralisation is dominantly epigenetic, sediment-hosted (typically greywacke and siltstone) and fold-controlled. Most gold is hosted by concordant or discordant veins, with limited alteration halos in host rocks, except where they occur in silicate-facies BIF or other Fe-rich rocks. The domal culminations of major doubly-plunging anticlines, and/or fold-limb thrust-faults, are important structural controls at the camp- and deposit-scales. Many deposits are sited in parts of the lithostratigraphy where there is significant competency and/or chemical contrast between units or sequences. In particular, the complex interdigitated stratigraphy of euxinic and transitional high-energy sedimentary rocks of the c.1900-1880Ma South Alligator Group is important for the localisation of gold deposits. The distribution of deposits is influenced further by the location and shape of granitoids and their associated contact-metamorphic aureole. Approximately 90% of gold deposits lie within the ∼2.5km wide contact-aureole, and most of these are concentrated in, and just beyond, the biotite-albite-epidote zone (0.5-1.0km from granitoid), with few deposits located in the inner hornblende-hornfels zone. At the deposit scale, gold is commonly associated with arsenopyrite-loellengite and pyrite, native-Bi and Bi-bearing minerals, and is confined to a variety of extensional quartz-sulphide ± carbonate veins. Such veins formed typically at 180-320°?C and ∼1kbar from low- to moderate salinity, two-phase aqueous fluids. Isotopic studies of the deposits are equivocal in terms of the source of hydrothermal fluid. Most δD and δ18O values fall within the range defined for contact-metamorphic and magmatic fluids, and sulphur isotopes indicate that the fluids are within the range of most regional sources. Significantly, lead isotope ratios show that the goldbearing fluid does not have a felsic magmatic-source signature, but instead suggest a homogenous regional-scale lead source. Excluding a few outliers, the relative uniformity of deposit characteristics, including host rocks, structural style, alteration, sulphide paragenesis and fluid P-T-X conditions, suggests that most deposits represent a continuum of broadly coeval mineralisation that formed under similar geological conditions

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14

Munir, Nazia Binte. "Manufacturing and Characterization of Gold-Black and Prediction and Measurement of its Directional Spectral Absorptivity." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/102097.

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Gold-black has emerged as a popular absorptive coating for thermal radiation detectors in aerospace applications. The performance and accuracy of thermal radiation detectors largely depends on the surface optical properties of the absorptive coating. If the absorptivity of the layer is directional or wavelength dependent, then so will be the detector gain itself. This motivates our interest in the manufacture, physical characterization, and study of the wavelength and polarization sensitivity of the directional spectral absorptivity of gold-black. A first-principle model based on lossy antenna theory is presented to predict the polarization dependent directional spectral absorptivity of gold-black in the visible and near infrared. Results for normal spectral absorptivity are in good agreement with measurements reported in the literature. However, suitable experimental data were not available to validate the theory for directional spectral absorptivity. Therefore, an experimental campaign to fabricate and measure the directional spectral behavior of gold-black had to be undertaken to validate the first-principle model. New in-plane bidirectional reflectance distribution function (BRDF) measurements for two thicknesses (~4 μm and ~8 μm) of gold-black laid down on a gold mirror substrate are reported in the visible (532 nm) and near-infrared (800 and 850 nm) for p- and s-polarizations. The investigation is then extended to a three-layer sample, which is shown to exhibit off-specular reflectivity. Described are processes for laying down gold-black coatings and for measuring their in-plane BRDF as a function of thickness, wavelength, and polarization state. A novel method for retrieving the directional absorptivity from in-plane BRDF measurements is presented. The influence of polarization on directional absorptivity is shown to follow our earlier theory except at large incident zenith angles, where an unanticipated mirage effect is observed.
Doctor of Philosophy
Instruments called thermal radiation detectors play an important role in monitoring the global climate from space. Gold-black is often used as an absorptive coating to enhance the performance of these instruments. Users need to know how gold-black coatings influence instrument performance. In general, coating properties depend on the wavelength and direction of incident radiation, as well as on an optical phenomenon called polarization. This dissertation investigates the relationship between the creation of gold-black coatings and their performance. A physical model is postulated for predicting the optical behavior of gold-black in the visible and near infrared. The model produces results that are in good agreement with measurements reported in the literature. However, suitable directional measurements were not available to validate the theory. Therefore, an experimental campaign was mounted to fabricate gold-black coatings and measure their optical behavior in order to validate the mathematical model. We observed the optical behavior of several of our gold-black samples of various thickness and over a range of wavelengths. We also studied a three-layer sample which was found to exhibit an unexpected behavior called off-specular reflectivity. Described are processes for creating gold-black coatings and for measuring and explaining their optical performance. During the course of this investigation an unanticipated mirage effect was observed for the first time.

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15

Mahizhnan, Annamalai. "Red-brown hardpan: distribution, origin and exploration implications for gold in the Yilgarn Craton of Western Australia." Thesis, Curtin University, 2004. http://hdl.handle.net/20.500.11937/1732.

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Red-brown hardpan occurs extensively in Western Australia in the arid and semi-arid regions of the Murchison, Pilbara and Eastern Goldfields divisions, between longitudes 115ºE and 124ºE and latitudes 23ºs and 30ºs. It occupies an area of about 360,000 sq. km, two thirds of which occurs in the Yilgarn Craton. The purpose of this research is to map the distribution of red-brown hardpan in the Yilgarn Craton of Western Australia; study the relationship between landscape, soil texture and vegetation; investigate the physical characteristics, petrology, mineralogy, geochemistry and cementing agents; and thereby determine the processes invaded in forming red-brown hardpan. The relation of red-brown hardpan to gold is investigated and determined its implications in mineral exploration. The main case study areas were the Goldfields Gas Pipe Line, the Federal Open Pit Gold mines and the Menzies district in the Kalgoorlie-Menzies region of the Eastern Goldfields; areas in and around the Woolgorong Station in the Murchison Province and at the Wiluna Gold Mines in the Northeastern Goldfields. The findings and conclusions of this research are summarised below. Red-brown hardpan occurs at or near the land surface and may vary from less than one metre to more than 10 m thick. It is exclusively developed in colluvium and alluvium, showing varying stages of cementation ranging from weakly cemented through moderate to strongly cemented. In addition, calcrete and red-brown hardpan occurs together in many places, south of the Menzies line, and this distribution suggests that red-brown hardpan was once more extensive and has been subsequently replaced by carbonate to form calcareous red-brown hardpan and calcrete. Red- brown hardpan predominantly occurs in regions with Q50 mm annual rainfall.In present-day higher rainfall (400 to 500 mm) regions, red-brown hardpan is being weathered. There is no relationship between the distribution of mulga (Acacia aneura) and red-brown hardpan. Red-brown hardpan is exclusively developed in colluvium containing a minimum of 20% quartz, 15% clays and 2% iron oxides. It is bright reddish brown to reddish brown, earthy, with a sandy loam texture, blocky structure and porous. Red-brown hardpan is hard (up to 12 MPa), being characterised by sub-horizontal laminations predominantly of uncemented kaolinite. Ped surfaces may be coated by Mn oxide and carbonate which may be precipitated along the laminations. The mineralogy of the cement is complex. Data from XRD, SEM, TEM, EFTEM, FTIR and NIR investigations show poorly-ordered kaolinite and opal-A as the main components. Illuvial multilayered argillaceous cutans containing silica and alumina in a ratio of 2:l form the cement. Secondary silica (SiO2-95%) coatings are common, mainly as opal-A, on ped surfaces and on the inner walls of voids and vughs. Etch pits are developed in these coatings and some of them are filled by kaolinitic clays. Selective dissolution experiments using acid ammonium oxalate show that oxalate- soluble amorphous and poorly ordered silica and alumina in red-brown hardpan have molar ratios of about 1.6 to 2 A1203:SiO2.These results suggest that red-brown hardpans were formed where there was sufficient water during the wet season to dissolve alumina and silica, but insufficient to leach them. During the subsequent dry season, the dissolved alumina and silica was precipitated as poorly-ordered kaolinite and opal-A. Successive dissolution and precipitation led to fusion of poorly-ordered kaolinite and opal-A at a nanometre scale to progressively cement the colluvium. The age of the red-brown hardpans, estimated by paleomagnetic dating of hematite, is from Pleistocene to present. Based on the findings of this research, the red-brown hardpan is redefined and primarily classified on its degree of cementation as: (1) weakly cemented, (2) moderately cemented and (3) strongly cemented. It is further classified chemically into: (1) siliceous, (2) calcareous and (3) ferruginous. In the Yilgarn Craton, red-brown hardpan is believed to occur mainly north of the 'Menzies Line'. However, this study reveals the presence of red-brown hardpan 75- 150 km south of the Menzies Line and the new southern boundary is closer to latitude 29ºs. Geochemical investigation at the Federal Open Pit Gold mines, Broad Arrow, north of Kalgoorlie indicate that there are Au anomalies in red-brown hardpan. Gold concentration is up to 50 ppb against the background anomaly of 10 ppb. Sequential and partial extraction analyses show significant correlation of Au with Ag, Ca, Ce, Co, Mg, Mn and Ni. This suggests that the Au concentration in red-brown hardpan is due to: (a) mechanical dispersion due to reworking of Au-bearing clasts in the sediment and (b) hydromorphic dispersion from the underlying mineralisation. It can therefore be used as a useful sampling medium for gold exploration.

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16

Mahizhnan, Annamalai. "Red-brown hardpan: distribution, origin and exploration implications for gold in the Yilgarn Craton of Western Australia." Curtin University of Technology, Department of Applied Geology, 2004. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15888.

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Red-brown hardpan occurs extensively in Western Australia in the arid and semi-arid regions of the Murchison, Pilbara and Eastern Goldfields divisions, between longitudes 115ºE and 124ºE and latitudes 23ºs and 30ºs. It occupies an area of about 360,000 sq. km, two thirds of which occurs in the Yilgarn Craton. The purpose of this research is to map the distribution of red-brown hardpan in the Yilgarn Craton of Western Australia; study the relationship between landscape, soil texture and vegetation; investigate the physical characteristics, petrology, mineralogy, geochemistry and cementing agents; and thereby determine the processes invaded in forming red-brown hardpan. The relation of red-brown hardpan to gold is investigated and determined its implications in mineral exploration. The main case study areas were the Goldfields Gas Pipe Line, the Federal Open Pit Gold mines and the Menzies district in the Kalgoorlie-Menzies region of the Eastern Goldfields; areas in and around the Woolgorong Station in the Murchison Province and at the Wiluna Gold Mines in the Northeastern Goldfields. The findings and conclusions of this research are summarised below. Red-brown hardpan occurs at or near the land surface and may vary from less than one metre to more than 10 m thick. It is exclusively developed in colluvium and alluvium, showing varying stages of cementation ranging from weakly cemented through moderate to strongly cemented. In addition, calcrete and red-brown hardpan occurs together in many places, south of the Menzies line, and this distribution suggests that red-brown hardpan was once more extensive and has been subsequently replaced by carbonate to form calcareous red-brown hardpan and calcrete. Red- brown hardpan predominantly occurs in regions with Q50 mm annual rainfall.
In present-day higher rainfall (400 to 500 mm) regions, red-brown hardpan is being weathered. There is no relationship between the distribution of mulga (Acacia aneura) and red-brown hardpan. Red-brown hardpan is exclusively developed in colluvium containing a minimum of 20% quartz, 15% clays and 2% iron oxides. It is bright reddish brown to reddish brown, earthy, with a sandy loam texture, blocky structure and porous. Red-brown hardpan is hard (up to 12 MPa), being characterised by sub-horizontal laminations predominantly of uncemented kaolinite. Ped surfaces may be coated by Mn oxide and carbonate which may be precipitated along the laminations. The mineralogy of the cement is complex. Data from XRD, SEM, TEM, EFTEM, FTIR and NIR investigations show poorly-ordered kaolinite and opal-A as the main components. Illuvial multilayered argillaceous cutans containing silica and alumina in a ratio of 2:l form the cement. Secondary silica (SiO2-95%) coatings are common, mainly as opal-A, on ped surfaces and on the inner walls of voids and vughs. Etch pits are developed in these coatings and some of them are filled by kaolinitic clays. Selective dissolution experiments using acid ammonium oxalate show that oxalate- soluble amorphous and poorly ordered silica and alumina in red-brown hardpan have molar ratios of about 1.6 to 2 A1203:SiO2.
These results suggest that red-brown hardpans were formed where there was sufficient water during the wet season to dissolve alumina and silica, but insufficient to leach them. During the subsequent dry season, the dissolved alumina and silica was precipitated as poorly-ordered kaolinite and opal-A. Successive dissolution and precipitation led to fusion of poorly-ordered kaolinite and opal-A at a nanometre scale to progressively cement the colluvium. The age of the red-brown hardpans, estimated by paleomagnetic dating of hematite, is from Pleistocene to present. Based on the findings of this research, the red-brown hardpan is redefined and primarily classified on its degree of cementation as: (1) weakly cemented, (2) moderately cemented and (3) strongly cemented. It is further classified chemically into: (1) siliceous, (2) calcareous and (3) ferruginous. In the Yilgarn Craton, red-brown hardpan is believed to occur mainly north of the 'Menzies Line'. However, this study reveals the presence of red-brown hardpan 75- 150 km south of the Menzies Line and the new southern boundary is closer to latitude 29ºs. Geochemical investigation at the Federal Open Pit Gold mines, Broad Arrow, north of Kalgoorlie indicate that there are Au anomalies in red-brown hardpan. Gold concentration is up to 50 ppb against the background anomaly of 10 ppb. Sequential and partial extraction analyses show significant correlation of Au with Ag, Ca, Ce, Co, Mg, Mn and Ni. This suggests that the Au concentration in red-brown hardpan is due to: (a) mechanical dispersion due to reworking of Au-bearing clasts in the sediment and (b) hydromorphic dispersion from the underlying mineralisation. It can therefore be used as a useful sampling medium for gold exploration.

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17

Fulton, Pamela J. "Distribution of gold mineralization at the New Britannia Mine in Snow Lake, Manitoba, implications for exploration and processing." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0010/MQ41702.pdf.

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18

Kelley, John Joseph. "Controlling Gold Nanoparticle Assembly through Particle-Particle and Particle-Surface Interactions." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1533083850424849.

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19

Serdar, Orhan. "Experimental Investigation And Modeling Of Dropwise Condensation On A Horizontal Gold Coated Tube." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605609/index.pdf.

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The phenomenon dropwise condensation on a horizontal gold coated tube is investigated by both analytical and experimental methods in this study. A computer program is prepared to calculate the dropwise condensation heat transfer rate on the horizontal gold coated tube. An experimental setup was also manufactured to measure the dropwise condensation heat transfer rate. The effects of flow rate, temperature of cooling water and also steam to wall temperature difference have been analytically investigated by using Mathcad computer program. Experiments were carried out at different inlet temperatures of cooling water. Effects of cooling water at different flow rates are also experimentally investigated. Results of the experiments are compared to those of the literature and the analytical results.

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20

Blanchard, Ian Geoffrey. "Determination and distribution of gold and the platinum group elements in the Devonian and Carboniferous rocks of south-west England." Thesis, Kingston University, 2000. http://eprints.kingston.ac.uk/20644/.

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A method has been developed for the determination of gold and the platinum group elements at the low concentrations found in most geological materials, utilising the advantageous properties of Inductively Coupled Plasma-Mass Spectrometry (lCP¬MS) analysis. The method has been applied to assess the distribution of the precious metals in south-west England. Results from this study are combined with previously published data on the distribution of precious metal enrichments and new fluid inclusion data, to determine the origin of these enrichments. The methodology developed uses a sodium peroxide fusion of a small (1.0 g) sample of powdered geological material, with separation by tellurium co-precipitation and determination by ICP-MS. Isotope dilution calibration is used where possibe to overcome losses through the procedure, but data for monoisotopic elements (Au, Rh) are obtained by external calibration. Detection limits for the method are excellent, being < 0.5 ng g-l for Au, Pt, Pd and the minor PGEs: Ru, Rh and Ir. Good agreement with reference data for certified reference materials WGB-l, TDB-l and UMT-l was obtained. Pd data were reliable throughout the method testing. Data for Pt and Au improved through the method development phase. The minor PGEs gave reliable data for high concentration reference materials. Field sample data were only reliable for Pd, Pt and Au; minor PGE concentrations were too low to allow quantitation. Low concentration Ir results showed a systematic error.Small quantities of gold have previously been found in south-west England. New data confirm the presence of gold in mineral materials from Hope Nose and LoddisweIl. Most of the area shows low precious metal concentrations, probably due to the lack of potential source rocks. Anomalous precious metal concentrations are found associated with deep-seated cross-course structures. These may have allowed the ingress of precious metal-bearing fluids from deeper crustal levels. A spatial association with greenstone basic volcanics is also seen, but the greenstones analysed do not show anomalously high precious metal concentrations. Palladium shows a greater dispersion than either Au or Pt; small amounts being detected in most areas sampled.

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21

Chitra, Eric, and n/a. "Bionomics of Culicoides molestus (Diptera: Ceratopogonidae): a pest biting midge in Gold Coast canal estates." Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20041119.101151.

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Culicoides molestus (Skuse) is the major species of biting midge that plagues human comfort in the estuarine Gold Coast region of southeast Queensland. Local authorities have initiated a search for an effective, non-chemical means of control, that would minimize human-midge interaction. The effectiveness of a program to control an organism, such as a biting midge, is dependent upon knowledge of the biology of the particular organism of interest. This project revolved examines the lifecycle of C. molestus in detail. It addresses questions regarding the location, seasonal distribution, and dispersal of its juvenile stages in the sand of infested beaches, and their response to chemical treatment, the monthly and annual cycles of the adult midge, and the possibilities of achieving laboratory oviposition, as a first step to laboratory colonisation. The distribution of eggs, larvae and pupae of C. molestus was found to be mostly concentrated around, but below, mean tide level. They also occurred well below the mean tide level. Eggs and larvae have been recovered from as deep as 10 cm in the sand. A seasonal study of the juveniles of this species indicated that they were more strongly influenced by tides than seasons. After a routine pest-control larviciding treatment, a beach recolonisation study revealed that beaches become suitable for oviposition approximately two months after treatment. Large larvae invaded the sprayed areas within days of treatment, which suggests the existence of a refuge outside of the reach of the insecticide. Larvae found in clean (egg- and larva-free), isolated sand containers, placed on the study beach, indicated that larvae could swim in or on the water as a way of moving around the beach. Extended bite-rate studies highlighted the existence of four peaks in adult midge biting activity during the course of a year, around the mid seasons. The strongest peaks of activity were found to be in autumn and spring, but the data suggest that the species undergoes four generations in a year. Through a series of trial-and-error experiments, oviposition under laboratory conditions was achieved. Although the time from blood-feeding to egg maturation is not yet well determined, it occurs within an eight day mean survival period. Blood quality appears critical for adult blood-fed midge survival. Midges fed on the blood of a volunteer who was frequently exposed to midge bites do not live long enough to mature its eggs. The partial ovarial development of one unfed adult female, reared in the laboratory, indicates that C. molestus is facultatively anautogenous.

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22

Hou, Zhihui. "Sediment budget of gold and magnetite and their distribution in stream sediment in lower Harris Creek, south-central British Columbia, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0031/NQ27165.pdf.

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23

Rabeau, Olivier. "Distribution de l'or de type orogénique le long de grands couloirs de déformation archéens : modélisation numérique sur l'exemple de la ceinture de l'Abitibi." Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL073N/document.

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Cette thèse visait à mieux définir les méthodes de ciblage et apporter des éléments de réponse sur la genèse des gisements d’or de type orogénique en périphérie des grands couloirs de déformation archéens. Cette thèse est présentée sous forme de trois articles. Le premier article traite de la distribution mathématique des gisements aurifères de type orogénique le long des grands couloirs de déformation. Une approche permettant de d’établir que la localisation des gisements se situant le long de structure de premier ordre n’est pas indépendante de la localisation de ses voisins a été développée. Cette approche permet de donner des éléments de réponse sur la formation de ces gisements et de générer des probabilités de découvertes à l’échelle régionale. La deuxième partie de cette présente une méthode l’évaluation du potentiel minéral sous couverture sédimentaire en 3D. Les teneurs aurifères compilées dans le secteur ont permis d’évaluer et de quantifier les relations spatiales existantes entre certaines entités géologiques et les emplacements minéralisés afin de cibler les endroits à haut potentiel. Enfin, les travaux présentés dans le dernier chapitre visent à délimiter les zones possédant une perméabilité structurale accrue lors de l’épisode de déformation contemporain à la mise en place de gisements aurifères de type orogénique. Une modélisation géomécanique 3D qui tient compte des propriétés physiques des roches a été effectuée sur un segment de faille choisi en utilisant un code d’élément fini. La déformation s’effectue en attribuant sur chaque discontinuité structurale des vecteurs ou des champs de déplacement en fonction des observations de terrain
This thesis had the objective to define targeting methods adapted to orogenic gold deposits hosted in greenstone belts and to better understand the formation mechanism of these deposits. The work accomplished is presented in three distinct articles. The first article aimed to determine if a mathematical relation can characterize the spatial distribution of orogenic gold deposits along a crustal scale fault zone within or if the localization of a deposit is independent of the position of each other. A uniform law was fitted between the frequency and the curvilinear inter-distance between successive orogenic gold occurrences along the CLLF for distances ranging from 315 to 5600 m. This approach gave insights on the formation mechanism and allowed the generation of a probability map for undiscovered deposits at a regional scale. The second chapter of this thesis focuses on a sector of the Cadillac Larder Lake Fault that was considered as having a high potential for discovery using the methodology presented in the last chapter. Compiled assays allowed the evaluation of the spatial association of certain geological features with orogenic gold mineralizations to allow targeting high potential areas. Finally, the work presented in the last chapter aimed at identifying dilatant zones during the deformation that is contemporaneous to the orogenic gold deposit formation. A 3D geomechanical modelling which takes rock properties into account was performed on a chosen segment of a fault zone using a finite element code. The deformation was induced using displacement vectors or fields interpreted from field data

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24

Oosthuizen, Nicolas Laurens. "Optimum water distribution between pumping stations of multiple mine shafts / Nicolas Laurens Oosthuizen." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9189.

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In 2011 the mining industry purchased 14.5% of the electrical energy generated by Eskom. During 2011 in South Africa, dewatering pump systems on gold mines were the fourth largest electrical energy consumer on South African mines therefor making dewatering pumps ideal candidates to generate significant financial savings. These savings can be realised by controlling time-of-use (TOU) schedules. Previous studies concentrated on the impact of improving a pumping scheme of a single mineshaft. This dissertation will focus on the operations of a complete dewatering system consisting of multiple mineshafts. The case study will consist of a gold mine complex comprising of five different shafts - each with its own reticulation system – as well as the larger interconnected water reticulation system. Various pumping options were investigated, simulated and verified. The interaction between shafts was determined when load-shifting was scheduled for all the shafts taking each shaft’s particular infrastructure into account. The underground dewatering system was automated and optimised based on the simulation results. Mine safety protocols were adhered to while optimal pump operational schedules were introduced.
Thesis (MIng (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

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25

Joshi, Chakra Prasad. "Understanding Fundamentals of Plasmonic Nanoparticle Self-assembly at Liquid-air Interface." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1387306468.

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26

MARQUES, ANDRE L. F. "Medida do fluxo de neutrons termicos do reator IPEN/MB-01 com detectores de ativacao de fios de sup197Au." reponame:Repositório Institucional do IPEN, 1995. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10456.

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Made available in DSpace on 2014-10-09T12:38:56Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:59:43Z (GMT). No. of bitstreams: 1 02755.pdf: 2809959 bytes, checksum: a21b5dc47bef9cb4b424a52336924fa8 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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27

Agarwal, Abhiruchi. "Nanocarrier mediated therapies for the gliomas of the brain." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39468.

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Existing methods of treating glioma are not effective for eradicating the disease. Therefore, new and innovative methods of treatment alone or in combination with existing therapies are necessary. Delivery of therapeutic agents through delivery carriers such as liposomes diminishes the harmful effects of the agent in healthy tissues and allows increased accumulation in the tumor. In addition, targeted chemotherapy using liposomes provides the opportunity for further increase in drug accumulation in tumor. However, the current targeting strategies suffer accelerated plasma clearance and are not advantageous in improving efficacy. The search for new tumor targets, novel ligands, new strategies for targeting, and particle stabilization will advance our ability to improve delivery at the tumor level while decreasing toxicity to normal tissues. The global objective of this thesis was to improve the status of current liposomal therapy to achieve higher efficacy in tumors. Here, we show a novel mechanism to increase targeting to tumor while uncompromising on the long circulation of stealth liposomes. Long circulation is essential for passive accumulation of the nanocarriers due to EPR effect, in order to see benefits of targeting. Using phage display technique, a variety of tumor specific peptides were identified for use as targeting moieties. One potential advantage of the approach proposed here is the rapid identification of patient tumor specific peptide that evades the RES. This could lead to the development of a nanocarrier system with high avidity and selectivity for tumors. Therefore, tumor accumulation of the targeted formulations will be higher than that of non‐targeted liposomes due to increased drug retention at the tumor site and uncompromised blood residence time.In addition, it has been shown that the distribution of nanocarriers, spatially within the tumor, is limited that might further hinder the distribution of the encapsulated drug, thereby limiting efficacy. It is necessary to release the drug from within the nanocarrier to promote increased efficacy. Here, we were able to address the problem of drug diffusion within the tumor interstitium using a combination therapy employing a remotely triggered thermosensitive liposomal chemotherapeutic. We fabricated a thermosensitive liposomal nanocarrier that maintained its stability at physiological temperature to minimize toxicity to healthy cells. We, then, showed a remote triggering mechanism mediated by gold nanorods heated via NIR can help in achieving precise control over the desired site for drug release. These strategies enabled increased drug availability at the tumor site and contributed to tumor retardation. Additionally, we show that the synergistic therapy employing gold nanorods and thermosensitive liposomes may have great potential to be translated to the clinic.

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28

Tete, Lisa. "Modelling Local pH Values and Ion Distributions near Gold Nanoparticles." Thesis, Umeå universitet, Kemiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-186565.

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Corrosion is the sum of processes by which an element, commonly a metal, wears away, deteriorates [1]–[3]. One of these processes uses the principle of electrochemistry as a basis, being the transfer of electrons between one chemical reaction and the element that undergoes corrosion [4], [5]. One example of electrochemical corrosion in everyday life is steel corrosion [6]. Iron contains electrons that can be taken up by oxygen in an acidic environment through the following reaction: O2 + 2 H2O + 4 e-  4 OH-. This reaction taking up electrons is defined as a reduction. These electrons come from iron which releases them, this process being defined as an oxidation reaction: Fe(s)  Fe2+ + 2 e-. The resulting redox reaction is maintained by the movement of electrons between two poles, often electrodes, an anode where the oxidation occurs and a cathode where the reduction occurs [7]. Iron, which was more inert is now available as an ion for interacting elsewhere in its environment. As metals have an important place in our society, so does electrochemical corrosion. Being infrastructure, medicine, food storage or transportation, corrosion must be kept under control. For instance, corrosion of metallic biomaterials can severely compromise their biocompatibility [8], [9]. Research has led to various solutions to drastically reduce corrosion caused by external environments. Metals in trace amounts also have an important impact, particularly on health. Due to their size, they can easily be absorbed by living species; this can be beneficial for health purposes for instance but, if absorbed in excess, it can also lead to a panel of risks [10]–[12]. The metal used in this project is gold. Due to its properties and sensitivity to its environment as a nanoparticle, gold has proven to be beneficial, especially in life science and modern medicine [13]–[15]. However, drawbacks behind the intensive use of gold nanoparticles (GNP) are less known and more complex to study. The variation of the pH in the bulk solution has been studied for this project. The explored assumption is that corrosion of these nanoparticles is guided by changes of the bulk pH, which is often linked to electrochemical reactions, themselves described by the Nernst equation [16]–[18]. During corrosion, the surface pH changes. This is of interest in this project and has been indirectly monitored by both the bulk pH and the surface potential. Pourbaix diagram is an example of this link between potential and pH values: it focuses on the potential of the species of interest. Depending on their sizes and whether there is a current, pH should be calculated either at the particle surface or in the bulk solution. Indeed, the current density can translate a pH difference between the two positions. As the species react at their surface, pH value there can deviate a lot from the bulk pH value. To observe pH changes, Hydrogen Oxidation Reaction (HOR) has been selected as it leads to a H+ production: H2  2 H+ + 2 e-. It has often been used for this purpose [16], [17], [19], [20]. The concept behind this project originates from another study, “Near-surface ion distribution and buffer effects during electrochemical reactions”, studying HOR on a rotating Pt disc electrode [20]. Here, researchers have studied effects that the pH, represented in the Nernst equation, has on the current density near the electrode. The previous study has been adapted for this project by now studying pH effects on the current density near spherical GNPs. Additional studies such as Oxygen Reduction Reaction (ORR) and diffusion limitation from hydrogen- and oxygen supplies have been considered in the project. The simulations have been performed on MATLAB software.

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29

Hullo, Marie. "Place des nanoparticules pour lutter contre la radio-résistance du cancer du sein : impact de l’hétérogénéité tumorale Gold Nanoparticle Uptake in Tumor Cells: Quantification and Size Distribution by sp-ICPMS . Radiation Enhancer Effect of Platinum Nanoparticles: Experimental in Vitrolimits Andrelevant Physical Chemical Simulation." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASL004.

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L’utilisation de nanoparticules de haut numéro atomique pour potentialiser les effets de la radiothérapie fait l’objet de nombreux travaux de recherches. Historiquement, l’intérêt porté à ces nanoparticules repose sur un principe d’action physique : en densifiant la matière, les nanoparticules localisées dans une tumeur augmentent localement la probabilité d’interaction des rayonnements ionisants avec celle-ci. L’augmentation de la dose délivrée localement serait alors associée à un stress oxydatif et à une augmentation des lésions de l’ADN. Ainsi la radio-sensibilisation liée aux nanoparticules permettrait d’une part de lutter contre la radio-résistance et d’autre part d’améliorer l’index thérapeutique. La radiothérapie constitue l’un des piliers du traitement du cancer du sein. Néanmoins, les tumeurs mammaires sont hétérogènes et plusieurs sous populations coexistent avec des sensibilités différentes aux traitements. Les cellules souches cancéreuses (CSC) et le processus de transition épithélio-mésenchymateuses (TEM) contribuent principalement à cette hétérogénéité et confèrent aux cellules tumorales des propriétés de plasticité, de tumorogénicité et de résistance à la mort cellulaire. Dans le cas particulier du cancer du sein, les cellules issues de la TEM et les cellules souches cancéreuses partagent un même phénotype surfacique caractérisé par la perte d’expression de la protéine membranaire CD24 et la surexpression de CD44. Ce travail de thèse vise à évaluer l’efficacité de nanoparticules métalliques de nature (or, platine), de taille (5 à 35 nm) et de charges (positives, négatives) différentes comme agents potentialisateurs des effets de l’irradiation sur des modèles de tumeurs mammaires aux statuts épithélio-mésenchymateux différents. Face à la difficulté à mettre en évidence un effet biologique significatif du double traitement in vitro, j’ai cherché à comprendre quels paramètres physiques, chimiques et biologiques sont nécessaires pour observer l’effet radiosensibilisant. L’un des principaux enjeux a été de parvenir à une bonne diffusion des nanoparticules au sein des tumeurs. Pour comprendre les mécanismes, nous avons comparé la réponse transcriptomique de cellules cancéreuses mammaires, au fond génétique commun mais de phénotype épithélial ou mésenchymateux (triées selon leur niveau d’expression CD24/CD44), exposées à un groupe de nanoparticules de composition physico-chimique différente de manière à s’affranchir d’un l’effet qui serait spécifique à une nanoparticule. L’analyse du transcriptome souligne l’importance des structures membranaires et extracellulaires dans la reconnaissance et l’interaction préférentielle des nanoparticules avec les cellules mésenchymateuses. Ces résultats sont d’autant plus importants que l’identification de gènes et de mécanismes clés favorisant l’accumulation de nanoparticules dans les cellules cancéreuses les plus résistantes aux traitements devrait permettre d’améliorer la conception de nouvelles nanoparticules à haut potentiel thérapeutique
The use of high-Z nanoparticles to enhance radiotherapy effects has gained momentum over the last decade. Historically, as nanoparticles increase tumor density, they were thought to improve radiation dose by locally increasing the probability of interactions with ionizing radiations. Local dose enhancement is then associated with increased oxidative stress and DNA damage. Therefore, radiosensitization with nanoparticles could impair radioresistance as well as improve therapeutic index. Radiotherapy is a cornerstone of breast cancer treatment. However, mammary tumors are heterogeneous and comprise distinct populations of cancer cells that respond differently to treatments. Cancer stem cells (CSC) and epithelial to mesenchymal transition (EMT) are major factors contributing to cancer cells plasticity, tumor heterogeneity, and escape from programmed cell death (apoptosis). In breast cancer, both CSC and cells undergoing EMT are characterized by the expression of two surface markers CD24 and CD44 (CD24-/low, CD44 high). This work aims to evaluate the efficiency of high-Z nanoparticles of different nature (gold, platinum), different size (from 5 to 35 nm) and different surface charge (positive and negative) as potent radiosensitizer on several breast cancer models of different epithelial or mesenchymal state. As no significant change could initially be observed in vitro following the combination of nanoparticles with radiation compared to radiation alone, I gain insight on the influence of physical, chemical and biological parameters required for characterizing radio-enhancement. Among them, I focused on improving the diffusion of nanoparticles and their internalization in tumor cells. I showed that nanoparticles uptake by breast cancer cells was depending on their mesenchymal state: nanoparticle internalization by cancer cells is dramatically increased in mesenchymal-like cancer cells compared to epithelial-like cells across a panel of several breast cancer cell lines. Importantly this discrepancy was not affected by the charge, size or surface chemistry of the nanoparticles themselves. This strongly suggests a cell-dependent mechanism, in opposition to the current paradigm that nanoparticles uptake is mainly governed by their inherent physical/chemical properties. This study emphasized the importance of membrane and extracellular structures in nanoparticle recognition and preferential interaction with cells. Our results are of peculiar interests as the identification of genes or mechanisms facilitating nanoparticles accumulation into radioresistant cancer cells could further conception of promising therapeutic nanoparticles

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Larsson, Mina. "Application of Raman and Fluorescence Spectroscopy to Single Chromatographic Beads." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5741.

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31

Taylor, Linda Lea. "Storage of Pine Tree Substrate Influences Plant Growth, Nitrification, and Substrate Properties." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/40342.

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Pine tree substrate (PTS) is a relatively new substrate for container crop production. There are no detailed studies that elucidate how storage time impacts PTS chemical, physical, and biological aspects. The objective of this research was to determine how PTS storage time influenced PTS chemical and physical properties, nitrification, and plant growth. Pine tree substrate was manufactured by hammer-milling chips of loblolly pine trees (Pinus taeda L.) through two screen sizes, 4.76 mm (PTS) and 15.9 mm amended with peat (PTSP). PTS and PTSP were amended with lime at five rates. A peat-perlite mix (PL) served as a control treatment. Prepared substrates were placed in storage bags and stored in an open shed in Blacksburg, Virginia. Subsamples were taken at 1, 42, 84, 168, 270, and 365 days. At each subsampling day, twelve 1-L containers were filled with each substrate. Six containers were left fallow and six were planted with marigold (Tagetes erecta L. â Inca Goldâ ) seedlings. Substrate was also collected from select treatments for Most Probable Number assays to estimate density of nitrifying microorganisms, and for chemical and physical property analyses. Pour-through extracts were collected from fallow containers at 0, 2, and 4 weeks, and from marigold containers at harvest for determination of pH, electrical conductivity, ammonium-N and nitrate-N. At harvest, marigold height, width, and dry weight were measured. At least 1 kgâ ¢m-3 lime for PTS, and 2 to 4 kgâ ¢m-3 lime for PTSP were needed to maintain pH values â ¥ 5.5 for 365 days. Bound acidity of unlimed PTS increased but cation exchange capacity for unlimed PTS and PTSP decreased over 365 days. Carbon to nitrogen ratio and bulk density values were unchanged over time in all treatments. There were minor changes in particle size distribution for limed PTS and unlimed and limed PTSP. Marigold growth in PTS and PTSP was â ¥ PL in all limed treatments, except at day 1. Nitrite-oxidizing microorganisms were present and nitrification occurred in PTS and PTSP at all subsampling days. Pine tree substrate is relatively stable in storage, but pH decreases, and lime addition may be necessary to offset this decrease.
Ph. D.

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Serra-Diaz, Josep M., Brian J. Enquist, Brian Maitner, Cory Merow, and Jens-C. Svenning. "Big data of tree species distributions: how big and how good?" SPRINGER HEIDELBERG, 2018. http://hdl.handle.net/10150/626611.

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Background: Trees play crucial roles in the biosphere and societies worldwide, with a total of 60,065 tree species currently identified. Increasingly, a large amount of data on tree species occurrences is being generated worldwide: from inventories to pressed plants. While many of these data are currently available in big databases, several challenges hamper their use, notably geolocation problems and taxonomic uncertainty. Further, we lack a complete picture of the data coverage and quality assessment for open/public databases of tree occurrences. Methods: We combined data from five major aggregators of occurrence data (e.g. Global Biodiversity Information Facility, Botanical Information and Ecological Network v.3, DRYFLOR, RAINBIO and Atlas of Living Australia) by creating a workflow to integrate, assess and control data quality of tree species occurrences for species distribution modeling. We further assessed the coverage - the extent of geographical data - of five economically important tree families (Arecaceae, Dipterocarpaceae, Fagaceae, Myrtaceae, Pinaceae). Results: Globally, we identified 49,206 tree species (84.69% of total tree species pool) with occurrence records. The total number of occurrence records was 36.69 M, among which 6.40 M could be considered high quality records for species distribution modeling. The results show that Europe, North America and Australia have a considerable spatial coverage of tree occurrence data. Conversely, key biodiverse regions such as South-East Asia and central Africa and parts of the Amazon are still characterized by geographical open-public data gaps. Such gaps are also found even for economically important families of trees, although their overall ranges are covered. Only 15,140 species (26.05%) had at least 20 records of high quality. Conclusions: Our geographical coverage analysis shows that a wealth of easily accessible data exist on tree species occurrences worldwide, but regional gaps and coordinate errors are abundant. Thus, assessment of tree distributions will need accurate occurrence quality control protocols and key collaborations and data aggregation, especially from national forest inventory programs, to improve the current publicly available data.

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Frimpong-Manso, Yaw. "Land-tenure in the Hebrew Bible in relation to the land-tenure system of the Akan (Asante) of Ghana." Thesis, University of Aberdeen, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310633.

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This study investigates the ideas and conceptions underlying the religious, political and socio-economic principles governing landholding in the Hebrew Bible in relation to the system of land-tenure among the Akan people of Ghana. The Asante as a social unit is used to represent the entire Akan group as a microcosm of the world picture. The primary thrust of the thesis is that the Hebrew Bible reflects some basic conceptions of land which can be compared and contrasted with a contemporary socio-economic system of land administration for implications of land-tenure and use. The Hebrew Bible presents three main types of land ownership: 1) divine ownership of land, a basic theological assertion that land belongs to Yahweh absolutely and that all others, including Israel are God's tenants; 2) communal ownership of land based on the segmentary patrilineage system whereby the tribes and families hold land in trust for members of the community; 3) private ownership of land, an innovation developed as a result of social change. The Asante traditional belief also accepts the principle of divine ownership of land, but while it attributes creation to God, it also affirms that land basically belongs to the ancestors who pass it on to the present and future generations of the society. The other two types of land-tenure, communal and private, are represented in the Asante social system, though with some differences. Stool, lineage and family heads hold land in trust, but on fiduciary basis in the sense of holding both a proprietary and beneficiary interest in the land of which they are custodians. But the corporate matrilineage group is the basic socio-economic factor as far as traditional landholding in Asante is concerned.

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Trauernicht, Christoph Jan. "Measured and calculated dose distributions in the “claws” – a specially designed gold applicator loaded with I-125 seeds." Doctoral thesis, Faculty of Health Sciences, 2020. http://hdl.handle.net/11427/32371.

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Introduction: The “Claws” is a unique gold applicator for whole-eye radiotherapy that was designed at Groote Schuur Hospital. It is used to treat retinoblastoma. Under general anaesthesia, a pericorneal ring is attached to the four extraocular muscles, and four legs, each loaded with I125 seeds, are inserted beneath the conjunctiva in-between each pair of muscles and attached anteriorly to the ring. The four legs that are now sutured onto the ring give it a claw-like appearance, hence the name for the applicator. The applicator was designed in such a way that the dose is directed towards the middle of the eye, while sparing surrounding tissues. The dose to the organs at risk could never be determined accurately, because the treatment planning system (TPS) is not able to take into account the gold shielding. Additionally, the TPS approximates each seed as a point source and not as a line source, therefore not taking any anisotropy into account. Aims: The first aim of this project was to accurately determine various dosimetric and physical characteristics of a single I-125 seed and to then compare these to published data. Spectral measurements of the OncoSeed 6711 using various detectors were also done. The next aim was to formalize the model of the “Claws” so that the applicator can potentially also be manufactured elsewhere. The next aim was to describe the “Claws” dosimetrically. This was done - Using thermoluminescent dosimeters in a solid water phantom - Using gafchromic film in a solid water phantom - Using treatment planning systems TheraPlan Plus and BrachyVision - Using Monte Carlo simulations – egs_brachy The final aim of the thesis was the comparison of measured and calculated data. The Monte Carlo simulations take into account the seed anisotropy as well as the gold shielding; therefore the relative dose to critical structures can be estimated more reliably. Method and Materials: Gafchromic film and thermoluminescent dosimeters (TLDs) were used for measurements in various specially designed phantoms to determine the seed parameters, as well as dose distributions in the eye. Dose distributions were calculated on two treatment planning systems. A CAD drawing of the “Claws” was created and used to create the input file for Monte Carlo simulations using egs_brachy. The final Monte Carlo calculation simulated 64.000.000.000 particle histories at voxel sizes of 0.1 mm x 0.1 mm x 0.1 mm. Results: Measured seed data matched published seed data. Significant dose distribution changes were found when comparing measured and Monte Carlo data to planned data, especially near the periphery of the eye between adjacent legs. The Monte Carlo calculated dose to the optic nerve is 64.8 % of the central dose in the eye, while the planned dose is 93.7 %. The Monte Carlo lens dose varies from 72.0 % - 86.1 %, while the planned dose varies from 73.0 % - 84.3 %. Monte Carlo calculated dose to the bony orbit is 11.3 %, while the planned dose is 54.7 %. Conclusion: Measured seed data matched published seed data. The “Claws” were formalized with CAD drawings. Measured and Monte Carlo simulated dose distributions matched well, while planned dose distributions showed discrepancies in certain regions of the eye and outside of the eye. This clearly indicates that the gold shielding of the applicator walls must be taken into account during dose calculations. It can be concluded that the “Claws” were extensively described and characterized in this work.

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Mowat, Christopher. "Star formation in the Gould Belt : a submillimetre perspective." Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/34652.

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This thesis presents my work characterising star formation in Gould Belt molecular clouds using submillimetre observations from SCUBA-2 on the James Clerk Maxwell Telescope (JCMT). I use these observations alongside data from previously published surveys using instruments including the Spitzer Space Telescope. I investigate the effect of including submillimetre data on the numbers, classifications and lifetimes of Young Stellar Objects (YSOs) in Gould Belt molecular clouds, particularly protostars. Following a literature review, I use SCUBA-2 450 and 850 μm observations to characterise star formation in the Lupus I molecular cloud. A total of eleven previously identified YSOs are detected with SCUBA-2, as well as eleven starless cores. Two cores have masses greater than the Jeans mass, and one has a virial parameter of 1.1 0.4, meaning these cores could be unstable against collapse. I use submillimetre emission to calculate disk masses, and find that one YSO has a disk mass greater than the minimum mass solar nebula. I find that Lupus I has a high percentage of both protostars and Very Low Luminosity Objects (VeLLOs). I also fit YSO Spectral Energy Distributions (SEDs) with models, allowing protostellar envelope masses and temperatures to be calculated, and interstellar extinction to be constrained for some YSOs. The signs of recent and future star formation support the hypothesis that a shock has triggered a star forming event in Lupus I. I also use SCUBA-2 data in conjunction with archival Spitzer and Herschel data to produce SEDs for five new candidate First Hydrostatic Cores (FHSCs) in Serpens South. These observations were then fit with models by the first author of this work, Alison Young. This work was able to identify two of the FHSC candidates as probable FHSCs, and constrain the rotation rate and inclination of one of them. I use JCMT Gould Belt Survey (GBS) observations of ten molecular clouds to produce an updated catalogue of protostars in these clouds. I use the FellWalker algorithm to find individual sources in the SCUBA-2 maps, and match them to the Spitzer YSO catalogue of Dunham et al. (2015). I use bolometric temperature to classify 362 out of 592 candidates as Class 0 or Class I protostars - a factor of two increase compared to the Spitzer catalogue due to improved submillimetre coverage. I find that protostellar lifetimes of 0.59 – 0.89 Myr - approximately 25 % longer than previously estimated. I also calculate protostellar luminosities, envelope masses, and envelope temperatures, and examine the distributions. Finally, I newly identify 19 protostars as VeLLOs, and increase the number of known VeLLOs in these clouds by a factor of two.

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36

Xu, Bei. "Les approches extrêmes de la contagion sur les marchés financiers." Thesis, Bordeaux 4, 2012. http://www.theses.fr/2012BOR40033.

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La thèse est composée de trois parties. La première présente un certain nombre de mesures de dépendance extrême. Une application sur les actions et les obligations de 49 pays montre que la théorie des valeurs extrêmes multivariées conduit aux résultats différents de ceux issus du coefficient de corrélation, mais relativement proches de ceux obtenus du rho de Spearman conditionnel multivarié. Cette partie évalue aussi le risque de pertes importantes simultanées. La deuxième partie examine les déterminants des co-mouvements extrêmes entre 5 pays core et 49 pays non core. Les mécanismes de transmission des chocs varient de la période moins récente à la période récente, des pays développés aux pays émergents, des chocs normaux aux chocs extrêmes. La troisième partie étudie le rôle de valeur refuge de l’or sur la période 1986-2012. Les gains positifs extrêmes de l'or peuvent être liés aux pertes extrêmes du S&P. Cependant, ce lien n'est pas toujours valable, il évolue dans le temps et serait conditionné par d'autres facteurs
The thesis consists of three parts. The first part introduces a number of measures of extreme dependency. An application on stock and bond markets of 49 countries shows the multivariate extreme value theory leads to results which are different from those from the correlation coefficient, but relatively close to those obtained from multivariate conditional Spearman's rho. This part also assesses the risk of simultaneous losses. The second part examines the determinants of extreme co-movements between 5 core countries and 49 non-core countries. Transmission mechanisms of shocks vary from less recent to recent period, from developed to emerging markets, from normal to extreme shocks. The third part examines the role of safe haven of gold over the period 1986-2012. Extreme positive gains of gold can be linked to extreme losses of S&P. However, this relationship is not always valid, it evolves over time and could be determined by other factors

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Gaier, Robyn Renee. "Understanding God's justice towards those who suffer : a critique of Eleonore Stump's defense /." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1107802929.

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Richie, Cristina. "Moving Environmental Bioethics into the 21st Century: Green Bioethics and the Common Good." Thesis, Boston College, 2016. http://hdl.handle.net/2345/bc-ir:106939.

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Thesis advisor: James Keenan
Environmental conservation is a pressing issue for modern humans. Health care systems and the consumption of medical goods should therefore be assessed in light of environmental sustainability. While the primary focus of environmental bioethics has been hospitals and health care facilities, ethicists must also address the offerings of the medical industry going forward. My dissertation proposes four principles to assess the environmental sustainability of current and future medical developments, techniques, and procedures. The four principles of green bioethics are: 1. General allocation of resources should precede special interest access: distributive justice 2. Current human needs over current human wants: environmental conservation 3. Simplicity before complexity: reducing dependence on medical intervention 4. The common good should drive health care instead of financial profit: ethical economics. The four principles of green bioethics will move environmental bioethics into the 21st century in a responsible and sustainable manner
Thesis (PhD) — Boston College, 2016
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Theology

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Mendoza, Leyva Irene Rebeca. "Does God favor the unequal distribution of resources? a study of the effects of religion on ethnic conflicts /." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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40

Boshoff, C. R. "Structure, distribution and phenology of perennial plant species in the Worcester Veld Reserve, in the arid winter rainfall region of the Southwestern Cape." Master's thesis, Faculty of Science, 1989. https://hdl.handle.net/11427/31874.

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High structural diversity amongst plant species in the arid winter rainfall region of southern Africa is common to other arid regions of the world. Details of the range and combinations of structural attributes in species, and within plant communities, are not widely known for southern African arid ecosystems. Hence little is known of how plant-form distributions vary within and between arid ecosystems. and of the environmental factors that may be responsible for any variations found. Nor is much information available on how phenological behaviour relates to the structural attributes of plant species. This study examined structural attributes of perennial plant species on the Worcester Veld Reserve, southwestern Cape. in relation to their distribution and phenology. Species were grouped on the basis of above ground structural and anatomical criteria. The distribution of species and plant-forms was assessed through a phytosociological survey along an environmental gradient in the area, and their phenology determined through qualitative and quantitative monitoring of species phenophases over a two year period. The results show that species of the predefined structural groups i) Co-occur throughout the area. but relative abundances vary from site to site and in relation to topography. aspect and the presence of Mirna-like mounds; ii) Phenological patterns for the flora overall are strongly seasonal, but the timing and periods of phenophases differ between, but are relatively uniform within, the defined structural plant groups. Since phenological patterns are indicative of resource-use patterns. these results indicate that the different plant-forms have different functional responses to the conditions of limited water availability and summer drought. This conceivably facilitates the co-existence of species in this water-limited environment. Habitat variability. which can be related to land-form patterns. is also implicated as a factor facilitating the co-existence of a diversity of species and plant-forms. Structural functional relationships known for arid region plants help to explain the relative uniformity of behaviour within plantform groups. and aid in understanding the ecological significance of distribution patterns of plant-forms in the arid landscape. The conclusion is reached that because of the close coupling between photosynthesis and water-use. the water storage potential and photosynthetic organ type are plant attributes which can serve as useful criteria by which arid region species can be grouped into ecologically meaningful categories or functional guilds. The formulation of a practical and meaningful functional classification is necessary to facilitate the understanding of complex vegetation patterns and processes within arid ecosystems. and allow for meaningful inter-ecosystem comparisons.

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Lo, Caleb. "How the self-transcendent emotion of awe affects cooperation, distributional preferences and reporting of the five factor model of personality traits." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132685/1/Yuheng_Lo_Thesis.pdf.

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The emotion of awe has been proposed to lead to behavioural shifts. This experimental study explores how induction of awe impacts cooperation through a repeated public goods game, distributional preferences through the equality equivalence test, and personality reporting through the five factor model of personality traits. It sheds light onto the study of prosocial behaviour, personality reporting and the experimental methodology of awe.

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Wiss, Erik, and Andrée Theander. "Från färdiginspelat låtmaterial till mastrings-ideal, digitala distributionsavtal, ersättning från en radiokanal, pressade CD-skivor i kartongfodral och en budget med god vinstmarginal." Thesis, University of Skövde, School of Humanities and Informatics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-1122.

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Syftet med det examensarbete som genomförts har varit att kartlägga processen för att på egen hand lansera sin musik i form av ett fullängdsalbum tillgängligt att köpas både i form av digitala nedladdningar och som traditionell CD-skiva.

I arbetet har vi bekantat oss med viktiga aspekter angående distributionsavtal, upphovsrätt, marknadsföring, design, foto, logotyper, texter och koder man bör känna till. En stor del av arbetet har även ägnats åt att förklara och utreda den sista delen i ljudbearbetningen - mastring. Dessutom har vi satsat på marknadsförning och exponering på Internet samt olika betalningslösningar som möjliggör skivans försäljning.

För att erhålla de nödvändiga delarna i arbetsprocessen har kontakt upprättats med bland andra: IFPI, Grammotex, N©B och Dicentia.

I rapporten får vi följa den progressiva rockgruppen Cap Outrun och deras väg till målet i form av en fallstudie.

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Passerat-Palmbach, Jonathan. "Contributions to parallel stochastic simulation : application of good software engineering practices to the distribution of pseudorandom streams in hybrid Monte Carlo simulations." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00858735.

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The race to computing power increases every day in the simulation community. A few years ago, scientists have started to harness the computing power of Graphics Processing Units (GPUs) to parallelize their simulations. As with any parallel architecture, not only the simulation model implementation has to be ported to the new parallel platform, but all the tools must be reimplemented as well. In the particular case of stochastic simulations, one of the major element of the implementation is the pseudorandom numbers source. Employing pseudorandom numbers in parallel applications is not a straightforward task, and it has to be done with caution in order not to introduce biases in the results of the simulation. This problematic has been studied since parallel architectures are available and is called pseudorandom stream distribution. While the literature is full of solutions to handle pseudorandom stream distribution on CPU-based parallel platforms, the young GPU programming community cannot display the same experience yet. In this thesis, we study how to correctly distribute pseudorandom streams on GPU. From the existing solutions, we identified a need for good software engineering solutions, coupled to sound theoretical choices in the implementation. We propose a set of guidelines to follow when a PRNG has to be ported to GPU, and put these advice into practice in a software library called ShoveRand. This library is used in a stochastic Polymer Folding model that we have implemented in C++/CUDA. Pseudorandom streams distribution on manycore architectures is also one of our concerns. It resulted in a contribution named TaskLocalRandom, which targets parallel Java applications using pseudorandom numbers and task frameworks. Eventually, we share a reflection on the methods to choose the right parallel platform for a given application. In this way, we propose to automatically build prototypes of the parallel application running on a wide set of architectures. This approach relies on existing software engineering tools from the Java and Scala community, most of them generating OpenCL source code from a high-level abstraction layer.

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Henderson, Robert Mark. "Leadership and the life of God distribution of ministerial gifts and leadership practices at the Quail Springs Church of Christ /." Theological Research Exchange Network (TREN) Access this title online, 2004. http://www.tren.com.

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Simard, Louis. "Distribution, abondance et écologie saisonnière des principaux insectes ravageurs du gazon sur les terrains de golf du Québec et évaluation du potentiel de contrôle des nématodes entomopathogènes indigènes." Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/24118/24118.pdf.

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46

Murray, Eamon. "A comparison between the theological approach of the 1992 Australian Catholic bishops' statement on the distribution of wealth in Australia, Common wealth for the common good, and some selected theological types." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1995. https://ro.ecu.edu.au/theses/1161.

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The Bishops of the Australian Catholic Church have been issuing annual statements on political, economic and social issues since 1940. The focus of this thesis, the 1992 Bishops' Statement, Common Wealth for the Common Good, has as its main theme the distribution of wealth in Australia. It is the culmination of a five year process of consultation and drafting by the Bishops' Committee for Justice, Development and Peace (BCJDP), under the direction of its Executive Secretary, Dr Michael Costigan. This thesis attempts to identify the theological approach, or perhaps approaches. of the Bishops' Statement by comparing it to five selected theological types. Tile instrument used to assist in the comparison is comprised of a number of theological and socio-economic disciplines. Each of the types and the Bishops' Statement are analysed according to their use of the disciplines and then the Bishops' Statement is compared to the types to conclude whether it matches any one type in particular. This thesis concludes that the Bishops' Statement does in fact correlate almost exactly with one of the selected theological types.

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47

Krčálová, Jana. "Řízení jakosti a řízení reklamací ve společnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2010. http://www.nusl.cz/ntk/nusl-222737.

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This masters thesis deals with the current state of quality control system and control of complaints. Based on the information obtained from the analysis of the current situation in the company there is proposal of options and methods for quality improvements and control of complaints in the distribution process.

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48

Polo, Marcelo. "A discriminação de preço nas redes contratuais de distribuição : abordagem civil e concorrencial." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/142950.

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O presente trabalho estuda a vedação da discriminação de preço nas redes contratuais de distribuição, tanto pelo aspecto concorrencial, quanto pelo aspecto civil. A abordagem concorrencial decorre da existência de um ilícito assim tipificado na Lei Antitruste brasileira. É preciso identificar os requisitos de aplicação próprios do direito concorrencial, que tem como bem jurídico tutelado a defesa da concorrência. Fez-se um estudo de direito comparado com o direito concorrencial norte-americano, em que vigente o Robison-Patman Act. A abordagem de direito civil-contratual depende da identificação dogmática da existência de uma rede contratual, a partir da verificação da finalidade econômica global em um dos elementos essenciais dos contratos individuais que formam a rede. Necessário, ainda, proceder à qualificação jurídica dos contratos de distribuição, partindo da sua causa e dos demais elementos estruturais que informam se tratar de um contrato atípico. A vedação à discriminação decorre da incidência da cláusula geral do art. 187 do CC/02, que proíbe o abuso do direito em razão de um exercício que exceda manifestamente os limites impostos pelos dois critérios trabalhados: a finalidade econômica ou social do direito e a boa-fé. Distingue-se a boa-fé enquanto criadora de deveres laterais de conduta da confiança enquanto protetora de uma situação de confiança. A vedação à discriminação de preço decorre do standard de boa-fé na função de criadora de deveres de conduta para o organizador da rede diante dos distribuidores que lhe estejam vinculados nessa rede contratual. O referencial valorativo é a lealdade que se espera do organizador da rede nesse contexto negocial. Estuda-se os diversos critérios econômicos justificativos do que seja uma justa e leal diferenciação de preço sob o influxo do conceito operativo de igualdade elaborado no âmbito do direito público.
This paper studies the prohibition of price discrimination in contractual networks of distribution, both by the competitive aspect, as the civil aspect. The competitive approach stems from the existence of an unlawful this way typified in Brazilian Antitrust Law. One need to identify the requirements for application of competition law, which legal interest is to protect competition, not competitors. There is a comparative study with the U.S. competition law, because of the current rules of Robinson-Patman Act. The approach of civil-contract law depends on the identification of a network contract from the scanning of the global economic interest in one of the essential elements of individual contracts that compose the network. Also necessary to proceed with the legal classification of the distribution contracts, from his structural and functional (“consideration”) elements that informs it as an atypical contract. The prohibition of discrimination price arises from the general clause of art. 187 of the Civil Code of 2002, which prohibits the abuse of rights in respect of an exercise that clearly exceed the limits imposed by the two criteria worked: the economic or social purpose of the right and good faith. It is distinguished the good faith in its function of create duties of the confidence of a trust situation. The prohibition of price discrimination stems from the standard of good faith in its function of create duties of conduct to the organizer of the network of distributors. The reference value is the loyalty expected of the organizaer of the network in this negotiating context. We study the different economic criteria to be evidence of an equitable and fair price differentiation under the influence of the operating concept of equality established under public law.

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49

Costa, André Brandão Nery. "Os contratos que viabilizam o processo de distribuição e os efeitos de sua denúncia unilateral." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7679.

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Trata-se de dissertação elaborada com o escopo de identificar os efeitos da denúncia unilateral exercida no âmbito dos tipos contratuais instrumentalizados ao processo de distribuição de bens e serviços, a partir do exame das diferenças tipológicas entre cada um deles. Aludidos tipos contratuais correspondem ao de agência, de representação comercial autônoma, de concessão comercial e de franquia, cujos contornos ainda são frutos de intenso debate doutrinário. No ordenamento pátrio, enquanto alguns tipos contratuais não sofreram regulamentação legal, outros tais como o de agência, de representação comercial autônoma, de concessão comercial de veículos autores e de franquia são regulados legislativamente, em fenômeno a que não se assiste em nenhum outro ordenamento da família romano-germânica. A construção da disciplina de tais consequências jurídicas transpassa pela delimitação do âmbito de incidência de cada um desses regimes legais, os quais podem atribuir consequências jurídicas próprias. Os tipos de agência e de representação comercial são equivalentes, o que permite tratá-lo de maneira conjunta, enquanto aqueles de concessão comercial e de franquia, a despeito de apresentarem diferenças relevantes, também podem ser examinados em conjunto pela similar estruturação dos interesses, a despeito de apresentarem peculiares leis regulando-os. Após realizado o exame legislativo e tipológico, examinou-se o impacto do princípio da boa-fé objetiva na determinação dos efeitos desencadeados pela resilição unilateral exercida pelo produtor nos contratos por tempo indeterminado, assim como a influência da previsão do parágrafo único do art. 473 do Código Civil na delimitação desses corolários jurídicos no que tange aos tipos contratuais analisados. Realizado essa investigação, constatou-se que, conquanto existam inúmeros fatores que distanciem, de um lado, os tipos de agência e de representação comercial autônoma e, de outro, de concessão comercial e de franquia, os efeitos desencadeados pela denúncia unilateral são semelhantes, próximos àqueles das relações de duração e nas quais existe estreita confiança.
This dissertation aims to identify the effects of unilateral termination of contractual types exploited under the economic process of distribution of goods and services, from the examination of typological differences between each of these contracts. Alluded contractual types correspond to the agência, representação comercial autônoma, concessão comercial and franquia, which contours are still fruit of intense doctrinal debate. In the Brazilian legal system, while some contractual types suffered no legal regulation, others such as agência, representação comercial autônoma, concessão comercial de veículos automotores and franquia are regulated legislatively, in a phenomenon that it is not witnessed in any other roman-germanic legal system. The construction of the discipline of such legal consequences pierces the scoping incidence of each of these statutory schemes, which may assign legal consequences of their own. It was found that the types of agência and concessão comercial are equivalent, allowing to treat them jointly, while those of concessão comercial and franquia, despite presenting relevant differences, can also be examined jointly as they present a similar structure of interests, despite presenting peculiar laws regulating them. After the legislation and typological examination, it was examined the impact of the principle of good faith in determining the effects triggered by the notice to quit of the producer in contracts for an indefinite period, as well as the determining influence of the sole paragraph of article 473 of the Brazilian Civil Code in the legal definition of these corollaries with respect to the contractual types analyzed. It was found that while there are numerous factors that distance themselves the effects triggered by unilateral withdrawal are similar and close to those of the contracts relational contracts.

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Bandeira, Paula Greco. "Contrato incompleto." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8363.

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A tese objetiva construir, sob o ponto de vista dogmático, critérios para a caracterização do contrato incompleto no direito brasileiro, estabelecendo o traço distintivo de sua causa e a disciplina jurídica que lhe é aplicável, à luz da metodologia civil-constitucional. Pretende-se, ainda, na perspectiva funcional dos fatos jurídicos, que permite a qualificação do contrato incompleto como negócio jurídico que emprega a técnica da gestão negativa da álea normal dos contratos, definir parâmetros interpretativos que orientem a sua execução. Por representarem o esmorecimento voluntário da técnica regulamentar, os contratos incompletos exigem elevados padrões de cooperação entre os contratantes na integração das lacunas, a ensejar a incidência reforçada dos princípios da boa-fé objetiva, da função social e do equilíbrio contratual, relativamente aos contratos em que ocorre a gestão positiva da álea normal. Após investigar os mecanismos legais incidentes na hipótese de inadimplemento do dever de integração da lacuna, analisam-se os limites legais e valorativos a que se sujeitam os contratos incompletos. Em chave conclusiva, almeja-se estabelecer o contrato incompleto como negócio jurídico lícito e merecedor de tutela no atendimento aos interesses concretos dos particulares no exercício de suas atividades econômicas, a evidenciar os novos confins da autonomia privada na legalidade constitucional.
This thesis aimsto buildstandards, from a dogmatic point of view, to define the incomplete contract in Brazilian Law, establishingthe distinctive feature of its function(causa) and its juridical discipline, inlight of the civilconstitutional methodology. It also intendsto determine interpretative parameters for its performance, under the functional perspective of the juridical facts, which allows the definition of the incomplete contract as a juridical act which adopts the negative technique of distribution of risks (álea normal).Since the incomplete contract intentionally doesnot regulate every possible contingency, ahigh level of cooperation between the contracting parties is required in order to fill its gaps. As a result,incomplete contracts set a higher standard when referring tothe principles of objective good faith, social function and contractual balance,which will be applied with more intensitythan in juridical actswherethere is a positive distribution of risks (álea normal).After analyzing the legal mechanisms applicable to the breach of the duty offillingcontractual gaps, this work will examine the legal and axiological limits to the incomplete contracts. In conclusion, this thesis aims to establish the incomplete contract as a licit juridical act, worthy of protection,asitmeets the parties interests in its economic activities, highlighting new boundaries ofthe private autonomy in the constitutional legality.

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