Magíster en Gestión y Dirección de Empresas / El presente trabajo, analiza la metodología de Gestión de Proyectos utilizada en el Proyecto Óxidos Encuentro de Antofagasta Minerals S.A., y se compara descriptivamente con los estándares utilizados por la industria minera chilena, y mundialmente utilizados en el área de Gestión de Proyectos, como lo son PMBOK del Project Management Institute (PMI), y la metodología FEL de Independent Project Analysis (IPA). También, se analiza el tipo de contratación utilizada, comparándola con la de un contrato tipo EPCM para la etapa de ejecución, de forma de identificar diferencias, ventajas y desventajas. La metodología utilizada por el Proyecto OXE, consistió en que el Mandante asumió el gerenciamiento del proyecto, contrató por separado la ingeniería, realizó por su cuenta las compras y contratos, licitó y contrató la construcción, y por consiguiente, asumió la mayor parte de los riesgos de la ejecución. De acuerdo al análisis comparativo realizado respecto a PMBOK para la Ejecución de Procesos y para las Áreas de Conocimiento , se puede indicar que el Proyecto OXE cumple todas las recomendaciones y lineamentos definidos y compiladas por PMI para el desarrollo de proyectos de inversión de capital. Sin embargo, se recomienda realizar mejoras en las áreas de conocimiento de Gestión de Calidad y Adquisiciones, de manera de robustecer el Modelo de Gestión propuesto. Se destaca que las áreas de Gestión de Interesados, de Riesgos, de Recursos Humanos, Tiempo y Costos, fueron abordadas en forma adecuada y sobresaliente, permitiendo capitalizar las oportunidades que se dieron en el transcurso del proyecto. Según la metodología FEL de IPA, el análisis comparativo indica que los procedimientos ADS de AMSA se encuentran alineados y que fueron correctamente utilizados en el Proyecto OXE. Sin embargo, existen doce recomendaciones VIPs de IPA para el desarrollo de proyectos, las cuales se cumplen parcialmente, generándose oportunidades de mejora respecto a la utilización de software 3D, minimización de residuos, confiabilidad del proceso, mantenimiento preventivo y optimización energética. Respecto a la contratación tipo EPCM, se señala que el Proyecto OXE, consideró un equipo de profesionales experimentados internamente que administraran a los contratistas de ingeniería, de empresas colaboradoras en diversas áreas, de construcción y algunos EPC. Con ello, el equipo del mandante desarrolló el proyecto y servicios, pero no contaba con todos los sistemas y procedimientos que utilizan y poseen las empresas especialistas en EPCM, y a su vez fue limitado por los lineamientos corporativos de AMSA. Sin embargo, se ejecutaron acciones que permitieron disminuir las brechas existentes con un contratista tipo EPCM y se realizó un adecuado seguimiento de Riesgos, Costos y Plazos, que permitieron alcanzar gran parte de los factores de éxitos definidos, y cumplir con la mayoría de las directrices de PMBOK y FEL.

Selenium (Se) is an essential mineral with functions for both animals and humans. There are several regions in the world deficient in this mineral and studies have related Se supplemented with reducing cholesterol. Thus, the objective of this study was to evaluate the Se effect in different levels and sources in the diet finishing of Nellore cattle on the performance and meat quality. It was used 63 Nellore cattle (412 kg and ± 24 months of age) in a completely randomized design with two sources (sodium selenite and selenium-enriched yeast) and four supplementation levels (0; 0.3; 0.9 and 2.7 mg Se/kg DM). There were no changes in performance and carcass characteristics. The Se level reduced (P<0.01) lipid and proteins oxidation (TBARS and carbonyl) compared to the control treatment on retail display storage (0, 2, 4 and 6 days). Organic Se, regardless of level, provided Se 138% higher (P<0.0001) in meat and 22.6% higher (P<0.0001) in serum than inorganic Se. The activity of glutathione peroxides (GPx) in muscle was 288% higher for animals supplemented with selenium and consequently, the cholesterol concentration in L. dorsi was 10.2% lower (P<0.001). The serum HMG-CoA reductase concentration was 32.7% lower in animals receiving Se supplementation (organic or inorganic). In conclusion, Se supplementation in beef cattle diet is a way of naturally producing selenium-enriched meat and with better quality for human consumption. / O selênio (Se) é um mineral essencial com funções para animais e humanos. Existem várias regiões do mundo deficientes neste mineral e estudos têm relacionado a suplementação de Se com a redução do colesterol. Assim, o objetivo deste estudo foi avaliar o efeito de diferentes teores e fontes de Se na dieta de terminação de bovinos Nelore sobre o desempenho e a qualidade da carne. Foram utilizados 63 animais da raça Nelore (412 kg e ± 24 meses de idade) em delineamento inteiramente casualizado, com duas fontes (selenito de sódio e selênio levedura) e quatro teores de suplementação (0; 0,3; 0,9 e 2,7 mg Se/kg MS) em confinamento, durante 84 dias. Não houve alterações no desempenho e nas características de carcaça. O teor de Se reduziu (P <0,01) a oxidação lipídica e proteica (TBARS e carbonila) em comparação ao tratamento controle durante o armazenamento em simulação de exposição no varejo (0, 2, 4 e 6 dias). O Se orgânico, independentemente do teor, forneceu valor de Se 138% superior (P <0,0001) na carne e 22,6% superior (P <0,0001) no soro em relação ao Se inorgânico. A atividade glutationa peroxidase (GPx) no músculo foi 288% maior nos animais suplementados com selênio e, consequentemente, a concentração de colesterol na carne foi 10,2% menor (P <0,001). A concentração sérica de HMG-CoA redutase foi 32,7% menor nos animais que receberam suplementação de Se (orgânico ou inorgânico). Foi concluído que a suplementação com Se na dieta de bovinos de corte é uma forma de produzir carnes enriquecidas com selênio naturalmente e com melhor qualidade para consumo humano.

The desire of the minerals industry to be more sustainable has led towards the increasing development of by-products. One such industry is the production of Alumina. The Alumina industry in Australia is the major producer of alumina in the western world with over 25 million tonnes of Bauxite Residue per annum. Alcoa World Alumina (Alcoa) has three refineries in Western Australia producing approximately 20,000 tonnes of Mud and a similar level of Red Sand each day. These as yet unutilised potential resources are being stockpiled, occupying a significant footprint. It is widely recognised within industry that there would be economic, environment and social benefits if a sustainable use for these materials were found. One such potential by-product is the production of coarse bauxite residue (Red Sand), neutralised and washed low in salt. The main purpose of this research was to establish a potential market for this material, through scientific evaluation of Red Sand as a replacement of natural fine aggregate (Natural Yellow Sand) in concrete mixes. For this research, the mixed stream of Bauxite Residue (fine and coarse) obtained in the Bayer process was neutralized by a process of carbonation then washed using cyclones and counter current wash towers to a value added byproduct. The coarse particles (Washed and Carbonated Sand-WCS) of the stream were separated by Wet High Intensity Magnetic Separation technique (WHIMS) so that different segments such as High Iron Sand (HIS) and Low Iron Sand (LIS) were formed. Physical, chemical and mineralogical properties of these materials have been tested and compared with that of natural sand. Several mixes of concrete were then designed using Red Sand as a fine aggregate in order to verify their effects on strength and durability indicators of concrete. / The comparative analysis between normal mix proportions and the mix proportions utilizing Red Sand was also achieved. In addition, the impact of marine environment on concrete mix design and properties of manufactured concrete were evaluated with a series of standard laboratory tests. The findings were promising in terms of both mechanical properties and durability and suggested that Red Sand, in particular Low Iron Sand is likely to be effective in place of fine aggregates and can be used within marine grade concrete with no major differences when compared to normal concrete. From the results obtained, it can be deduced that this material can be used in a wide range of concrete applications in Civil Engineering and Construction.

A number of methods for the analysis of free amino acids in melon fruit have been evaluated experimentally. Analysis of their tBDMS derivatives by GC (gas chromatography) was found to be the most suitable for the mix of free amino acid found in the melon matrix. It affords good yields of amino acid derivatives with excellent gas chromatographic properties and characteristic mass spectra. The single-step derivatization procedure is highly reproducible and allows simultaneous analysis of asparagine and glutamine together with their corresponding acids. Changes in amino acids, sugars, the principal acids, volatiles and minerals in the free form were studied in the fruit mesocarp during development, ripening and storage of the fruits. Sucrose was the principal sugar, absent in young fruit but showing a dramatic increase during ripening while the levels of fructose and glucose remained constant during the whole course of fruit growth or slightly decreased during ripening and storage. The quantitative determination of 22 free amino acids was achieved by GC analysis using the method developed. Total aroma volatiles were determined using a headspace-gas chromatographic technique. They increased and reached a maximum value just before fruit full slip. Most of the esters characteristic of melon aroma were absent in young fruit but developed at the ripening stage. Changes in the quantities of mineral nutrients present in the fruits were determined by ICP-AES analysis. The concentrations of most elements increased thoughout the fruit development except for Ca which decreased markedly and Cu which decreased during early growth then fluctuated around lower values later in the development stage. All of the above changes can be related to the metabolic activity during fruit growth and maturation. Statistical analysis showed changes in TV, TSS, TS, pH, some free amino acids and some minerals were strongly correlated. / Master of Science (Hons)

A sequential extraction method was used to determine which dominant sedimentary mineral phase was involved in phosphorus retention in the sediments of Lake Rotorua and to verify the importance of iron phases in the role as a phosphorus sink. The observed influence of the experimental conditions upon the extent of phosphate adsorption to various iron phases shows a considerable quantity of phosphorus is present in the reducible phase and in the residual mineral phase. The phosphorus associated with iron(III) oxide phases was released into solution under reducing conditions when ferric iron oxide/oxyhydroxides, including amorphous and poorly crystalline Fe(III) phases, were solubilized. The residual primary and secondary mineral phases remained stable in the sediments until they were exposed to extremely acidic media analogous to strongly reducing conditions. Manganese is not involved in phosphorus retention to the same extent as iron. Aluminium phases present were released from surface complexes with relative ease and also from mineral structures under the prevailing conditions. The results show a strong agreement between aluminium and phosphorus suggesting it is associated with various aluminium phases to some extent. The sediments of Lake Rotorua are rich in organic-bound P which is released when organic material is oxidized under conditions analogous to anaerobic degradation. The degradation of refractory organic material represents a significant source of phosphorus for incorporation into diagenetic minerals forming in oxic and anoxic layers of the sediment. Heavy liquid separation of the sediments concentrated the small quantities of dense minerals into a separate fraction and the presence of iron sulfides could be verified. Three density fractions obtained by this method separated the diatoms (d less than 2.6 g cm-3), the silicates (d greater than 2.6 less than 3.7 g cm-3) and the heavy minerals (d greater than 3.7 g cm-3) present in the sediment sample. In the heavy mineral phase spherulitic framboidal pyrite and rhombohedrial siderite were observed by scanning electron microscopy (SEM). Energy dispersive x-ray fluorescence (XRF) analysis of the framboidal pyrite detected significant fluorescence's for sulphur and iron. The elemental analysis of siderite characterised it as an iron-rich, non-sulfidic particle with no phosphorus fluorescence. Particles were also observed that had a variable morphology to the framboidal pyrite minerals but similar ratio of Fe to S in the XRF spectrum. It is likely they are other stable forms of iron sulfides or pyrites in various stages of diagenetic dissolution. Digestion of the three density fractions shows the heavy mineral phase is significantly enriched in sulfur and in iron confirming the presence of sulfides. The sulfide-forming trace metals are concentrating in the heavy mineral phase but a progressive enrichment of trace metals down core is not found in the results. Many of the trace elements show maximum concentrations in the Tarawera tephra. There is a good agreement between iron and phosphorus in both treatments that implies iron phases are the predominant phosphorus fixers in the sediments of Lake Rotorua. However the identity of the phosphorus sink could not be confirmed by SEM or XRF analysis of the heavy minerals. The most likely explanations for the observed concentrations of iron and phosphorus and enrichment in the heavy mineral fraction are the persistence of the highly insoluble crystalline iron oxyhydroxides (goethite) in reducing sediments or the formation of the reduced iron mineral vivianite. Considering the density of vivianite it would have being taken into the heavy fraction by default which would account for the enrichment demonstrated by the solution analysis.

Downhole sampling of unboiled liquid at 1350 and 1500 m depth in the seawater-dominated Reykjanes high-temperature geothermal system in Iceland shows that metal concentrations measured at surface are minimum values due to mineral precipitation in the wells; by analogy of similar tectonic setting, host rocks and fluid composition, the metal concentrations measured in many black smoker vents at the seafloor are also minima. Fluids in the Reykjanes geothermal system react with mid-ocean ridge basalt at temperatures as high as 346°C and contain Fe 9-140 ppm, Cu 14-17 ppm, Zn 5-27 ppm, Pb 120-290 ppb, 1-6 ppb Au, and 28-107 ppb Ag. Fluids discharged at surface from the same wells have orders of magnitude lower metal concentrations due to precipitation caused by boiling and vapor loss during depressurization. Upstream of the orifice plate at high pressure (40 bar, 252°C) the precipitates consist mainly of sphalerite and chalcopyrite with a trace of galena and bornite. At the orifice plate of old wells, the pressure decreased sharply to 11 bar (188°C), resulting in abundant deposition of amorphous silica together with minor sphalerite and traces of chalcopyrite. In new wells the pressure at the orifice plate decreases to 22 bar (220°C); this pressure decrease and concomitant boiling causes deposition of fine-grained bornite-digenite solid solution together with sphalerite and galena on the fluid flow control valve. In high-pressure wells (average wellhead pressure 45-35 bar) most metals (mainly as sphalerite) are deposited downstream of the orifice plate, with up to 950 ppm Au and 2.5 wt.% Ag. Bulk concentrations in the scales vary between 15-60 wt.% upstream and downstream of the orifice plate and diminish from there. Iron increases up well from 8 to ~20 wt.% and decreases downstream of the orifice plate from 6 to 2 wt.% at the separation station; Cu downhole is ~3 wt.% but increases to 25 wt.% on the fluid flow control valve and then decreases; Pb downhole 100s ppm but at the wellhead is ~3 wt.%, increasing to 15 wt.% at the fluid flow control valve, then decreasing sharply from there.

Thermotherapy using natural thermal mud has played a crucial role for human health care since ancient times. However, recently the SPA and Wellness Centers have come into prominence with the exhaustion of primary reserves of natural thermal mud. In these centers, instead of natural thermal mud, peloids prepared using clay and/or clay minerals with thermal or mineral water through maturation process that changes the physicochemical properties of the clay and/or clay minerals. Turkey has several clay reserves / however, the investigation about their suitability for the pelotherapic applications is not adequate. The aim of this study is to investigate the mineralogical, chemical, and physicochemical properties of the 13 different samples collected from K&uuml / &ccedil / &uuml / khacibey, Hancili, and Kazbekir localities in &Ccedil / ankiri and Kizil&ouml / ren, Karadirek, and H&uuml / dai localities in Afyonkarahisar in order to evaluate their suitability for pelotherapic applications. The results of mineralogical, chemical, and physicochemical analyses including cation exchange capacity, swelling index, plastic index, water loss, specific surface area, grain size and cooling rate properties were compared with the results in the previous studies. For maturation process distilled water and two different commercial mineral water with different chemical compositions were used. At the end of the four week long maturation, the peloids are evaluated in the sense of consistency, ease of handling and pleasant sensation during application. Evaluation of analyses results showed that clay deposits in Hancili and K&uuml / &ccedil / &uuml / khacibey localities in &Ccedil / ankiri can be considered being suitable for pelotherapic applications. On the other hand, clay deposits in Kazbekir locality in &Ccedil / ankiri and in all three localities in Afyonkarahisar cannot be considered being suitable for pelotherapic purposes.

Downhole sampling of unboiled liquid at 1350 and 1500 m depth in the seawater-dominated Reykjanes high-temperature geothermal system in Iceland shows that metal concentrations measured at surface are minimum values due to mineral precipitation in the wells; by analogy of similar tectonic setting, host rocks and fluid composition, the metal concentrations measured in many black smoker vents at the seafloor are also minima. Fluids in the Reykjanes geothermal system react with mid-ocean ridge basalt at temperatures as high as 346°C and contain Fe 9-140 ppm, Cu 14-17 ppm, Zn 5-27 ppm, Pb 120-290 ppb, 1-6 ppb Au, and 28-107 ppb Ag. Fluids discharged at surface from the same wells have orders of magnitude lower metal concentrations due to precipitation caused by boiling and vapor loss during depressurization. Upstream of the orifice plate at high pressure (40 bar, 252°C) the precipitates consist mainly of sphalerite and chalcopyrite with a trace of galena and bornite. At the orifice plate of old wells, the pressure decreased sharply to 11 bar (188°C), resulting in abundant deposition of amorphous silica together with minor sphalerite and traces of chalcopyrite. In new wells the pressure at the orifice plate decreases to 22 bar (220°C); this pressure decrease and concomitant boiling causes deposition of fine-grained bornite-digenite solid solution together with sphalerite and galena on the fluid flow control valve. In high-pressure wells (average wellhead pressure 45-35 bar) most metals (mainly as sphalerite) are deposited downstream of the orifice plate, with up to 950 ppm Au and 2.5 wt.% Ag. Bulk concentrations in the scales vary between 15-60 wt.% upstream and downstream of the orifice plate and diminish from there. Iron increases up well from 8 to ~20 wt.% and decreases downstream of the orifice plate from 6 to 2 wt.% at the separation station; Cu downhole is ~3 wt.% but increases to 25 wt.% on the fluid flow control valve and then decreases; Pb downhole 100s ppm but at the wellhead is ~3 wt.%, increasing to 15 wt.% at the fluid flow control valve, then decreasing sharply from there.

Corporate finance reporting is based in rigorous, rules-based frameworks yet environmental and social reporting does not seem to have these normalised tools. The sustainable development of the business movement, in terms of increased environmental and social responsibility, will remain marginal as long as policy decisions maintain their direction towards old models of corporate governance that are not based on the key principles of the triple-bottom line, CSR and accountability. This thesis attempts to gauge to what extent Public-Private Partnership performs a transparent and independent source and appraisal of the standards of Governance for Sustainability for selected firms. This investigation is delimited to an Environmental Social Governance metric analysis and comparison of non-financial corporate data disclosure in sustainability reports from the mining and metals industry in the Nordic countries. It has been inferred from the analysis that an extrapolation can be made based on the financial predictions and trend prospecting of LKAB, Boliden Group, Lundin Mining Corporation, and the Swedish Association of Mines, Mineral and Metal Producers for the future growth of both the Nordic mining sector and sustainability reporting. As a result, ‘best-practice’ in reporting procedures could be exported to where demand is highest from pioneering firms with the ‘first-mover’ advantage, to SME’s and other interested firm’s outside of the Nordic countries. It has been identified that using the Global Reporting Initiative reporting framework enhances partnerships in businesses that adopt and use its index to the extent where it becomes integrated into their management chains and business strategies. The more comprehensively a firm discloses its non-financial performances with relation to the GRI framework, the more integrated reports appear to become. The standardisation of the accurate reporting and disclosure used from the GRI G3.1 varies greatly just between three firms in the same sector and region.

A novel approach for the production of soy protein isolates was investigated integrating electroacidification and membrane ultrafiltration. The effect of electroacidification on the ultrafiltration performance and physicochemical properties of the soy protein extracts was obtained by comparing an electroacidified (pH 6) and a non-electroacidified (pH 9) soy protein extract. The effect of membrane fouling on the permeate flux decline was studied in a hollow fiber and a dead end ultrafiltration system. Due to more significant membrane fouling, the permeate flux was always lower for the electroacidified extract, resulting in at least 1.5-fold increase in the total fouling resistance compared to the non-electroacidified extract. The total amount of protein deposited on the membrane surface during unstirred dead-end ultrafiltration was comparable (about 7 mg/cm2) for both soy protein extracts. The discrepancy between the total fouling resistance and the protein deposition estimates was attributed to the formation of denser (less permeable) fouling deposit for the electroacidified extract, which was supported by scanning electron microscopy studies of fouled membranes. The removal of carbohydrates and minerals was evaluated for direct ultrafiltration and two-stage discontinuous diafiltration using a hollow fiber system. The carbohydrate removal results were always consistent with the theoretical predictions, indicating that the carbohydrates were freely permeable across the membrane. In contrast, the minerals were partially retained by the membrane, but to a higher extent for the non-electroacidified extract, which demonstrated that the electroacidification pretreatment enhanced the mineral removal during the ultrafiltration. Incorporation of the diafiltration step improved the ash (mineral) and carbohydrate removal. Stronger electrostatic interactions between soy proteins, calcium/magnesium, and phytic acid (antinutrient) at alkaline pH resulted in less efficient removal of calcium, magnesium, and phytic acid during the ultrafiltration of the non-electroacidified extract compared to the electroacidified extract. Consequently, the soy protein isolates produced by electroacidification and the hollow fiber ultrafiltration had a lower mineral and phytic acid content. The protein content was at least 88 % (dry basis), with or without the electroacidification pretreatment. The study of the viscosity revealed that the electroacidification pretreatment reduced the viscosity of the soy protein extract, which resulted in a lower axial pressure drop increase during the ultrafiltration of the electroacidified extract compared to the non-electroacidified extract. Adjusting the pH of the electroacidified extract to 9 and the pH of the non-electroacidified extract to 6 had a great impact on the particle size distribution but only a marginal effect on the viscosity of the pH adjusted extracts. This indicated that the pH and the particle size distribution were not responsible for the viscosity difference between the electroacidified and the non-electroacidified soy protein extracts. It was proposed that the electroacidification pretreatment had some impact on the water hydration capacity of the soy proteins, which consequently affected the viscosity.