<p>In the U.S, more than 5.6 million commercial buildings are in operation and some include offices, schools, and childcare centers. These large buildings have complex indoor plumbing and often drinking water chemical and microbiological safety hazards can go undocumented. Generally, the larger the building’s square footage, the greater number of building occupants potentially exposed to the drinking water and greater amount and complexity of indoor cold and hot water piping and appurtenances. Because commercial buildings routinely undergo periods of low to no water use (e.g., holidays, weekends) cold and hot water can stagnate in the plumbing. This stagnation can allow for chemical and biological drinking water quality safety to deteriorate. This thesis work was designed to examine water safety challenges in school, childcare center, and office buildings to address existing knowledge-gaps.<br></p><p><br></p><p>The study described in Chapter 1 was conducted to better understand the risks of elevated copper levels at U.S. schools and childcare centers. Study goals were to: (1) understand occurrences of copper in school and childcare center drinking water systems, (2) review acute and chronic health impacts associated with the ingestion of copper contaminated water, and (3) examine the effectiveness of remedial actions to address copper in drinking water. Of the more than 130,000 schools and 856,000 childcare centers in the U.S., only about 1.7% of all those facilities had copper drinking water testing data recorded in a federal Safe Drinking Water database since the database was created in 1992. Of these facilities that were designated public water systems, about 13% (2,332) had reported a copper drinking water exceedance. Over a period of 30 years, very few studies have been conducted to document copper levels in schools and childcare centers. Available studies reported widely different sampling protocols and remedial actions. Flushing copper contaminated water from plumbing was the most evaluated remedial action, but flushing sometimes needed to be repeated indefinitely because copper exceeded safe limits within hours after flushing stopped. In-building water treatment with ion exchange systems and orthophosphate corrosion inhibitor addition have been used. At present, there is limited data from testing for copper in schools and childcare centers as well as studies to aid building managers in identifying and remediating copper occurrences. <br></p><p><br></p><p>The study described in Chapter 2 was designed to better understand chemical and microbiological quality in a green office building due to weekend stagnation events (~60 hours per event). Specific goals were (1) to investigate characterize disinfectant, pH, as well as heavy metal and microbial contaminant levels at the building point-of-entry and fixtures throughout the building, (2) understand how water quality varied spatially and by fixture use frequency, and (3) investigate the effectiveness of remedial actions on removing the water quality problems identified. As-built plumbing drawings were used to create a sampling plan and flushing plan. The total chlorine concentration decreased during stagnation (p < 0.05) and was highest at the building entry point (max 0.8 mg/L), and lower throughout the building (max 0.28 mg/L). Total cell counts were greater on Mondays compared to Fridays (p < 0.05). Legionella spp. was highest at the fixture with zero water use recorded during the study. Copper and lead levels throughout the building increase over the weekend (p < 0.05). Copper exceeded the U.S. federal health-based drinking water limit (1.3 mg/L) at 4 of the 12 tested locations. These locations all branched off the same riser. Manual fixture flushing temporarily reduced copper levels, but copper rebounded quickly prompting the need to flush fixtures every 19 hours. Results showed that drinking water testing should be required for building water systems before occupancy permits are issued, and after an extended stagnation period to understand worst case conditions. Testing should include disinfectant level, copper, lead, and legionella. <br></p><p><br></p><p>This thesis research found that a general lack of water testing data for existing office, school, and childcare center buildings inhibited a wider understanding of water safety risks. It is recommended that building officials adopt water testing as a requirement for building occupancy certificates. Testing should also be conducted periodically during the life of the buildings especially after unusually long stagnation periods (e.g., shutdowns or holiday breaks), and in buildings where children or other sensitive populations (e.g., elderly or people with underlying conditions) are occupants. Testing should include disinfectant level, copper, lead, and legionella at the point of entry and multiple locations throughout the building, depending on fixture use and building occupants. Without water testing, occupants may continue to be exposed to water that does not meet federal safe drinking water limits and go undetected. If contamination is found, building managers should review the flushing plan and potentially consider point of use water treatment to address short- and long-term water safety problems. <br></p>

Séries de diques máficos alcalinos fortemente a levemente insaturados em sílica ocorrem nas cercanias de Santo Antônio do Pinhal (SP) e Campos do Jordão (SP) na serra da Mantiqueira, SE Brasil. Estes intrudem o embasamento cristalino precambriano (Sul do Orógeno Brasília) e a intrusão máfica-ultramáfica alcalina Ponte Nova. As rochas alcalinas dessa região são cretáceas e compõem o magmatismo da província alcalina Serra do Mar (PASM). Em sua maioria, os diques são classificados como basaltos alcalinos e lamprófiros alcalinos. São porfiríticos, com a população de macrocristais formada principalmente por clinopiroxênio e olivina. Subordinadamente, macrocristais de kaersutita, sadanagaíta rica em titânio, e ocasionalmente, flogopita, enstatita, magnetita, espinélio e plagioclásio são registrados. Estes apresentam texturas de desequilíbrio, como sieve e embayment, que, associadas a estilos de zonamento complexo, indicam evolução magmática em sistema aberto. Este estudo envolve: (1) petrografia de detalhe por microscopia ótica e microscopia eletrônica de varredura, (2) análises químicas pontuais, de elementos maiores e menores por microssonda eletrônica e de elementos-traço por espectrometria de massa com plasma acoplado indutivamente e amostrador por ablação a laser (LA-ICP-MS), em diferentes zonas dos macrocristais máficos, e (3) geoquímica de rocha-total por fluorescência de raios X e ICP-MS. Estas análises foram realizadas com vistas à determinação da gênese destas populações de cristais zonados. A partir das composições obtidas, balanços de massa foram realizados para excluir a influência dos macrocristais nas composições globais dos corpos e obter uma estimativa composicional dos líquidos magmáticos, representados pela matriz fina a afanítica nestas rochas. As zonas dos macrocristais em equilíbrio com os líquidos calculados foram determinadas por meio da constante de equilíbrio de troca catiônica de Mg e Fe entre cristal e líquido, KdFe2+ -Mg2+ C/L . Estas relações de equilíbrio permitiram atribuir significados genéticos as zonas dos cristais, definindo-os como xenocristais, antecristais e fenocristais. Os primeiros (em desequilíbrio textural e químico com o a matriz) foram capturados e/ou reciclados de ambientes magmáticos precoces à consolidação da rocha, permitindo acessar processos magmáticos passados durante a evolução do sistema magmático. Xenocristais mantélicos foram indentificados exclusivamente em diques da suíte fracamente insaturada em sílica. Macrocristais de olivina zonada com centros Fo>90 e textura embayment, encontram-se ao lado de macrocristais de clinopiroxênio zonado com centro de diopsídio com cromo incolor, anédrico, com zonamento concêntrico step normal. Estes centros de diopsídio com cromo apresentam mg# (Mg/Mg+FeT em proporção molecular) 88-87, alto Ni, baixo Na2O, Al2O3, TiO2, Zn, Sc, Hf, Y, Zr, Sr e elementos terras raras (ETRs), compatíveis com peridotitos fáceis granada e granada-espinélio. Nessa mesma ocorrência, centros de macrocristais de piroxênio são classificados como enstatita (xenocristais) e apresenteam textura sieve, zonamento concêntrico step reverso, altos teores de MnO, Ni, Zn e muito baixos de ETRs. Quanto aos antecristais, cristais em desequilíbrio químico e textural com a matriz mas cogenéticos ao sistema magmático, os clinopiroxênios destacam-se nos diques fortemente insaturados em sílica. Os centros desses macrocristais são classificados como diopsídio (por vezes com cromo ou com sódio), augita, hedenbergita e egirina-augita. O diopsídio é incolor, subédrico, com textura glomeroporfirítica, sieve, zonamento setorial e concêntrico step reverso. Este centro antecristalino incolor apresenta alto mg# (83-80), Cr2O3, Ni, Sc, baixo Na2O, Zn e valores intermediários de Zr, Y, Hf e Sr, quando comparado aos demais antecristais. Centros verdes de augita e egirina-augita são encontrados nos diques de ambas as séries e apresentam textura embayment, sieve e zonamento concêntrico step. No geral os centros verdes tem baixo mg# (70-40), Cr2O3, alto MnO, Na2O, Zn, mas diferentes teores de MnO, Na2O, Li, Sc, Hf, Y, Zr, Sr e ETRs. Ti-augita, quimicamente classificada como diopsídio subsilícico com titânio, é euédrica, com textura glomeroporfirítica, zonamento concêntrico oscilatório e setorial e observada como borda em todos os macrocristais de clinopiroxênio, além de compor a matriz e agregados (textura glomeroporfirítica) com macrocristais subédricos de olivina (Fo<88). Estes dois últimos tipos, em desequilíbrio químico com a matriz hospedeira mas com texturas de cogeneticidade ao sistema magmático, são antecristais de um estágio magmático posterior a cristalização dos antecristais e captura dos xenocristais e em menor profundidade. Kaersutita euédrica a subédrica, com textura glomeroporfirítica, esquelética e zonamento concêntrico oscilatório é o cristal predominante nos lamprófiros alcalinos. Este também ocorre como macrocristal anédrico com textura sieve em alguns diques de olivina basalto. Nos anfibólios destaca-se o enriquecimento em Ba, Sr, Y, Nd, Zr e ETRs inversamente proporcional ao MgO. Flogopitas com titânio são observadas principalmente na matriz dos diques máficos alcalinos da Mantiqueira. Porém macrocristais são raros e observados com zonamento concêntrico step e setorial. Nos cristais de flogopita da matriz, ao aumento de vacância no plano octaédrico é proporcional as altas concentrações de Ti, Nb, Zr, Sr, Y e Li, quando comparado ao macrocristais. Os xenocristais de olivina e diopsídio com cromo, encontrados nos diques máficos da série fracamente insaturada em sílica, indicam incorporação de rocha encaixante mantélica e/ou da fonte. Já os magmas máficos fortemente insaturados em sílica se mostraram híbridos, a partir de modelagem com elementos-traço, entre a mistura de líquidos alcalinos máficos e félsicos, responsáveis por cristalizar em estágios precoces, os antecristais de clinopiroxênio nos diques. Um estágio em menor profundidade é indicado pela presença em todos os diques de fenocristais e antecristais de Ti-augita como borda, macrocristal isolado ou com textura glomeroporfirítica, cristal na matriz, sendo, por vezes, associado a olivina e anfibólio. Esta diversidade de macrocristais pode ser explicada pelo modelo complex plumbing system, onde a interconexão entre diferentes magmas, ao longo de distintos estágios com diversas encaixantes, sob profundidades diferentes da litosfera, se mostra eficiente na produção das feições petrográficas e químicas destas rochas por meio dos processos de mistura de magmas e incorporação da rocha encaixante durante a ascensão litosférica desses diques ultrabásicos alcalinos do Cretáceo na região ocidental da serra da Mantiqueira, província alcalina Serra do Mar. / Weakly to strongly silica-undersaturated mafic alkaline dike series occur nearby Santo Antonio do Pinhal (SP) and Campos do Jordão (SP) in a restricted area of the Mantiqueira range, SE Brazil. These are intrusive in the Precambrian crystalline basement (south of the Brasília orogen) and in the Ponte Nova mafic-ultramafic alkaline massif. These alkaline rocks are Cretaceous and are grouped as part of the Serra do Mar alkaline province (PASM). In the majority, the dikes are classified as alkaline basalts and alkaline lamprophyres. They are porphyritic, with the macrocryst population having clinopyroxene and olivine as main phases. Subordinatedly, kaersutite, and occasionally, phlogopite, enstatite, magnetite, spinel and plagioclase were found. These macrocrysts present desequilibrium textures, such as sieve and embayment, combined with complex zoning styles, which indicate a open-system magmatic evolution. The study involves: (1) detailed petrographic analyses by optical microscopy and scanning electron microscopy, (2) quantitative punctual analyses of major and minor elements by electron microprobe and trace element by laser ablation - inductively coupled plasma mass espectrometry (LA-ICP-MS) in different horizons of the main macrocrystic phases, and (3) whole-rock geochemistry by X-ray fluorescence and ICP-MS. These determinations were collected focusing in the determination of the genesis of each zone of zoned crystals. From the obtained compositions, mass balance calculations were done to exclude the macrocryst influence in the bulk compositions of the bodies and to have a compositional estimative of the melts, represented by the fine-grained to aphanitic matrices of these rocks. The crystalline zones of macrocrysts in equilibrium with the calculated melts were defined using the Mg-Fe exchange equilibrium constant between minerals and liquid, KdFe2+-Mg2+ C/L . The equilibrium relationships allowed the designation of genetic meanings to the the crystalline zones, being these classified as xenocrysts, antecrysts and phenocrysts. The first two types (in textural and chemical disequilibrium with the matrices) were captured and/or recycled from an early magmatic environment, allowing to access the former magmatic processes during the evolution of the system. Mantle xenocrysts were only identified in dikes from the weakly silica-undersaturated series. Macrocrysts of zoned olivine with cores having Fo > 90 and embayment texture were found together with zoned clinopyroxene macrocrysts, presenting incolor, anhedral Cr-diopside cores with normal concentric step zoning. These Cr-diopside cores have mg# (Mg/Mg+FeT in molecular proportions) 88-87, high Ni values and low Na2O, Al2O3, TiO2, Zn, Sc, Hf, Y, Zr, Sr and rare earth elements (REEs). These compositions are compatible with the garnet and garnet-spinel peridotite facies. On the same occurrence, cores of macrocrystic pyroxene are classified as enstatite (xenocryst) and present sieve texture, concentric reverse step zoning, and high levels of MnO, Ni, Zr and very low of REEs. Antecrysts, crystals in chemical and textural disequilibrium with the matrices but cogenetic to the magmatic system, were mainly formed by cores of clinopyroxene macrocrysts in strongly silica-undersaturated mafic alkaline dikes. The cores of these ones are classified as diopside (sometimes Cr-bearing of Na-bearing), augite, hedenbergite and aegirine-augite. The diopside is incolor, subhedral, with glomeroporphyritic and sieve textures, setorial and concentric reverse step zonings. They present higher mg# (83-80), Cr2O3, Ni, Sc values, lower Na2O and Zn, and intermediate Zr, Y, Hf and Sr concentrations when compared to the other antecryst. Green cores of augite and aegirine-augite are found in dikes of all series and present embayment and sieve textures and concentric step zoning. These have low mg# (70- 40), Cr2O3, high MnO, Na2O and Zn, but wide ranges of MnO, Na2O, Li, Sc, Hf, Y, Zr, Sr and REEs. Ti-augite, chemically classified as subsilicic Ti-bearing diopside, is euhedral, with concentric oscillatory and setorial zonings and found as rims in all clinopyroxene macrocrysts, as matrix crystals and as agregates (glomeroporphyrithic texture) with subhedral olivine macrocrysts (Fo<88). Some of these two minerals zones are in chemical disequilibrium with the matrix but with textural equilibrium of magmatic system, being classified as antecrysts from a next magmatic stage of antecrystals cristalization and xenocryst incorporation. Other horizons of Ti-augite are phenocrysts, in chemical equilibrium with the host melt. Euhedral to subhedral kaersutite, with glomeroporphyritic and skeletal textures and oscillatory concentric zoning is predominant in alkaline lamprophyres. Anhedral kaesutite crystals with sieve texture occurs as macrocrysts in some olivine basalts dikes. In these amphiboles, the enrichment in Ba, Sr, Y, Nd, Zr and REEs present negative correlation with MgO contents. Ti-bearing phlogopites are found mainly in the matrices of the mafic dikes from the Mantiqueira range. However, macrocrysts are rare and found with anhedral habit and concentric step and setorial zonings. The increase of vacancies in octaedric plane of the matrix crystals phlogopite is proportional with the concentrations of Ti, Nb, Zr, Sr, Y and Li, when compared with the macrocryst compositions. The olivine and Cr-diopside xenocrysts found in the mafic dikes from the weakly sílica-undersaturated series indicate the incorporation of mantle host rocks and/or source rocks. Otherwise, the magmas from the strongly sílica-undersaturated series are considered hybrids, based on the trace-element mixing modelling of alkaline mafic and felsic melts. These compositionally contrasting liquids are the responsible for the crystallization, in the earlier stages, of the different families of clinopyroxene antecrysts. On next stage, at lower depth, is indicated by the presence of phenocrysts and antecrysts of Ti-augite as rims, isolated or aggregate macrocrysts and matrix crystals, sometimes associated with olivine and amphiboles. This macrocryst diversity can be explained by the complex plumbing system model. In this model, the interconection between several magma reservatories along distinct evolution stages, with different host rocks during their ascent under several depths in the lithosphere, is considered a efficient way to explain the petrographic and chemical features found in these rocks. Processes of magma mixing and the incorporation of host rocks during the lithospheric ascent are registere for the ultrabasic alkaline Cretaceous dikes of the Mantiqueira range, Serra do Mar alkaline province.

<p><a>This dissertation focused on better understanding the fundamental processes that control organic and inorganic contaminant interaction with plastic plumbing pipes. Plastic pipes are increasingly being installed for drinking water plumbing, but their role in affecting drinking water quality has received little study. It is well-known that plastic pipes can sorb and release organic contaminants and be difficult to decontaminate. Several problems were identified in the literature and through discussions with industry: (1) Past guidance issued to communities affected by petroleum contaminated water does not seem to specifically consider plastic plumbing pipe remediation, (2) investigators have also identified heavy metals can accumulate on pipe inner walls, (3) Others have proposed certain heavy metals can catalyze plastic water pipe degradation, (4) No nondestructive cleaning methods were found for removing metal scales from plastic pipes.</a> These topics were a basis for studies conducted because lack of information inhibits greater protection of public health, safety, and welfare.</p> This dissertation involved the application of knowledge and techniques from the environmental engineering and science, polymer engineering, and material science disciplines. Chapter 1 focused on the response of copper and plastic pipes (i.e., chlorinated polyvinylchloride (cPVC), high-density polyethylene (HDPE), crosslinked polyethylene (PEX)) exposed to petroleum contaminated drinking water. Bench-scale results revealed that pipe rinsing followed by a single 3 day water stagnation period removed target monoaromatic hydrocarbons (MAH) from copper pipes, but much longer (<u>></u>15 days) time was required for decontaminating cPVC, HDPC, and PEX pipes. Benzene, trimethylbenzene and polynuclear aromatic hydrocarbons, some of which are not typically considered in drinking water contamination investigations, were found desorbed into clean drinking water from pipes. Future plumbing decontamination guidance should consider the conditions necessary for plastic pipe remediation. Chapter 2 describes the influence of drinking water conditions on heavy metal contaminant – low density polyethylene (LDPE) pellet surface interactions. Mixed metal drinking water solutions were applied and contained Cu, Fe, Mn, Pb and Zn at 30 µg/L. LDPE was selected as the model polymer because of its prior use for piping in Europe, use in bench-scale studies by others, and similarity to products used for the manufacture of more complex materials in the USA (HDPE, PEX). As expected, metal loadings were about 5 times greater for aged LDPE pellets suspended in solution compared to new LDPE pellets. This difference was attributed to the aged plastic surfaces having oxygen containing functional groups, increased surface area, and enhanced hydrophilicity. Metal loading was lower at pH >9.5 and in the presence of dissolved organic contaminants. The presence of free chlorine and corrosion inhibitor also decreased metal adsorption onto LDPE pellets. These factors likely enabled metal precipitation thereby not allowing metal species to adsorb to LDPE pellets suspended in water. XPS results showed deposited metals (i.e., Cu, Pb, Zn) primarily consisted of hydroxides and oxides. To further understand heavy metal – plastic pipe interactions, Chapter 3 involved the use of metal and plastic pipe rigs and exhumed PEX plumbing pipes. Exhumed cold and hot water PEX pipes contained a noticeable amount of heavy metals (i.e., most abundant metals were 2049 mg/m² Fe, 400 mg/m² Ca, 438 mg/m² Zn and 150 mg/m² P). Metal release and deposition onto PEX pipe was examined using bench-scale pipe rigs that contained new PEX pipe, brass valves, and copper pipe. Two water matrices (pH 4 and 7.5) and two temperatures (23^oC and 55^oC) were explored. The pH 4 water often accelerated metal leaching from brass valves, and a greater amount of heavy metals deposited on PEX pipes at high water pH and temperature (pH 4 and 55^oC) conditions. Oxygen containing functional groups were detected on PEX pipes connected to a brass valve or a brass valve combined copper pipe, but were not found on PEX pipe only (controls) samples, indicating that certain configurations may facilitate plastic pipe degradation. The last chapter describes the ability of a new lignin derived ligand to remove metal deposits from exhumed PEX plumbing pipes. When the ligand concentration was ≥ 5mM, more than 95% of sorbed metals (i.e., Cu, Fe, Mn, Pb and Zn) were removed. The ligand favored certain metals over others (Cu > Zn > Fe > Mn > Pb) and heavy metal removal mechanisms were proposed. This dissertation provides insights into the role of plastic pipes on drinking water quality. As plastic pipes continue to be installed, it is in the interest of public health, welfare, and safety to understand their role in positively and negatively affecting drinking water safety.

La particularité de l’Oldoinyo Lengai à émettre des laves natrocarbonatitiques fait de ce volcan un laboratoire naturel pour l’étude de la genèse de ces magmas. De nouvelles mesures isotopiques en hélium nous ont permis de constater que la signature des fumerolles est constante depuis 1988 malgré le changement morphologique considérable du cratère sommital lors de la dernière éruption subplinienne de 2007-2008. L’alternance des éruptions explosives et effusives n’engendre donc aucune modification majeure dans l’organisation du système hydrothermal qui est par conséquent profondément enraciné. Les xénolites cogénétiques qui ont été émis lors de l’éruption de 2007-2008 permettent d’étudier directement les processus magmatiques qui se déroulent dans la chambre magmatique active. La comparaison des signatures isotopiques des gaz rares (hélium) de la chambre magmatique et des volcans silicatés de la région d’Arusha montre que les deux types de magmatisme ont une source analogue identifiée comme un manteau lithosphérique subcontinental préalablement métasomatisé par des fluides asthénosphériques. De plus, ces signatures isotopiques confirment l’absence de contaminations crustale lors de la remontée du magma entre le manteau source et la surface. Une description pétrographique de détail couplée à une approche thermobarométrique, ainsi qu’à la détermination des modèles de solubilité des volatils dans les liquides phonolitiques, nous a permis d’identifier l’évolution du liquide dans la chambre magmatique et ses paramètres de stockage. Les résultats nous révèlent que le magma injecté en 2007 a une composition phonolitique et des teneurs élevées en volatils (3.2 wt.% de H2O et 1.4 wt.% de CO2) ainsi qu’une température d'environ 1060° C. Ce magma évolue ensuite dans la chambre magmatique crustale se trouvant à 11.5±3.5 km de profondeur jusqu’à atteindre une composition de néphélinite et une température de 880°C. Pendant sa différenciation, le magma silicaté s’enrichit en calcium, sodium, magnésium et fer alors que sa concentration en silice, potassium et aluminium décroit. Ces résultats concordent avec les précédents relatifs à cette éruption, ou aux produits volcaniques plus anciens émis tout au long de la vie du volcan. Cette similarité suggère qu’aucun changement majeur n’ait eu lieu dans l’organisation de la plomberie du volcan Oldoinyo Lengai au cours de son évolution. Les mesures en éléments traces (REE, HFSE et LILE) dans les minéraux cristallisés lors de cette séquence de différenciation, et les inclusions magmatiques associées montrent un enrichissement pouvant atteindre de 100 à 1000 fois la composition du manteau primitif. Une étude expérimentale préliminaire s’appuyant sur la composition du liquide de recharge (phonolite) et les conditions (P, T) identifiées pour la chambre magmatique nous a permis de reproduire l'immiscibilité entre un liquide silicaté et carbonatitique, processus à l’origine de la formation des carbonatites de l’Oldoinyo Lengai. La poursuite de ces travaux expérimentaux permettra de mieux contraindre la genèse des magmas carbonatitiques et ainsi comprendre les processus en jeux dans l’enrichissement en éléments traces des magmas carbonatitiques / The uniqueness of Oldoinyo Lengai to emit natrocarbonatite lavas makes this volcano a natural laboratory to study the genesis of these magmas. New helium isotopic data permit to assert that the signature of the fumaroles has been constant since 1988 despite the radical morphological change of the summit crater after the last sub-Plinian eruption in 2007-2008. The alternation of the effusive and explosive eruptions does not cause major modifications in the hydrothermal system architecture, which is inferred to be deeply rooted. Cognate xenoliths that were emitted during the eruption in 2007-2008 represent a unique opportunity to document the igneous processes occurring within the active magma chamber. The comparison between the noble gas (helium) isotopic compositions of the active magma chamber and those of the other silicate volcanoes of the Arusha region indicates that both types of magmatism have similar sources, identified as being a typical sub-continental lithospheric mantle, which was previously metasomatized by asthenospheric fluids. Moreover, these isotopic signatures confirm that no crustal contamination has occurred during the magma ascent from the mantle to the surface. Detailed petrographic descriptions coupled to a thermo-barometric approach, and to the determination of volatile solubility models for a phonolite composition, allow us to identify the melt evolution at magma chamber conditions and the storage parameters. These results indicate that the magma injected in 2007 has a phonolitic composition and contains a high amount of volatiles (3.2 wt.% H2O and 1.4 wt.% CO2) as well as a temperature around 1060° C. This magma subsequently evolved in the crustal magma chamber located at 11.5 ± 3.5 km depth until reaching a nephelinite composition and a temperature of 880°C. During the differentiation in the magma chamber, the silicate magma is enriched in calcium, sodium, magnesium and iron, whereas the content of silicate, potassium and aluminum decreases. Our results support previous studies related to this eruption, and are similar to the historical products emitted during the whole volcano history, permitting the suggestion that no major modification in the plumbing system has occurred during the Oldoinyo Lengai evolution. The trace elements (REE, LILE and HFSE) measured in the minerals and melt inclusions reveal a concentration reaching 100 to 1000 times the primitive mantle composition. A preliminary experimental study based on the recharge melt composition (phonolite) and identified magma chamber conditions (P, T) permits to reproduce the immiscibility between silicate and carbonatite liquids, key processes at the origin of the Oldoinyo Lengai carbonatites. The continuation of this experimental study will lead to a better comprehension of the carbonatite genesis, thus improving our understanding of the processes that are responsible for the enrichment in trace elements

Orientador: Marina Sangoi de Oliveira Ilha / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T03:47:26Z (GMT). No. of bitstreams: 1 Lima_LiwanaChiude_M.pdf: 1654795 bytes, checksum: 44e9ed5746c2489e5e6ee274dafa1b70 (MD5) Previous issue date: 2008 / Resumo: O comportamento do ser humano tem causado inúmeros danos ao meio ambiente, sendo necessário que se revejam atitudes e hábitos de consumo dos insumos em geral, dentre eles o uso da água. Apesar deste assunto se encontrar na pauta de discussões de vários países, percebe-se que as pessoas ainda não se atentaram para o fato de que a necessidade de preservação deste insumo é essencial para a sobrevivência humana e de que são agentes determinantes para a sua conservação dentro de uma edificação. Isto ocorre, muitas vezes, porque não é suficiente informar as pessoas sobre a crise da água, é necessário que elas revejam seus conceitos e valores, seus padrões de consumo, sintam-se sensibilizadas pelo problema e mudem de atitude em prol de um desenvolvimento sustentável. Inserido neste contexto, a partir de um programa de conservação de água desenvolvido no Hospital das Clínicas da UNICAMP, o presente trabalho consiste em um levantamento das atividades realizadas no uso doméstico da água nessa tipologia de edificação, por meio de entrevistas e da observação de sua forma de realização, de modo a identificar as principais fontes de desperdício e as ações a serem implantadas para o uso racional da água. Palavras-chave: sistemas prediais, uso racional da água, uso doméstico da água, hospitais, comportamento humano / Abstract: The human behavior has caused countless damages to the environment; consequently it is necessary to review attitudes and habits of resources consumption, among them the use of water. Although this subject is up for a discussion in several countries, it is noticed that most people still do not realize that the necessity for the water preservation is essential for human survival and that they play a decisive role in its conservation inside a building. In general, this often happens because it is not enough to inform the people about the crisis of the water, it is necessary to make them review their concepts and values, their consumption patterns and make them sensible of this problem, in order to change their attitude on behalf of a sustainable development. Inserted in this context, starting from a program of conservation of water developed at UNICAMP Hospital, this work consists of a study about the activities regarding the domestic use of water in this building. The results were obtained based on interviews and observing the users dealing with the water, in order to identify the main sources of waste and the actions that could be implanted for the rational use of water. Keywords: plumbing system, rational use of water, domestic use of water, hospitals, human¿ behavior / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil

The first part of this doctorate dissertation examines the factors influencing the occurrence and costs of pinhole leak corrosion as well as the household decisions for corrosion prevention and plumbing material selection. Three mail surveys of households were used to elicit the experiences with leaks as well as the optimal corrosion prevention and material choices. Probability modeling (i.e. MNL) and linear regression analysis were used to analyze survey responses. Pinhole leak occurrences were found associated with pipe type installed, property age, pipe failure history, and dwelling distance from a water treatment plant. The number and location of pinhole leaks in the dwelling and the pipe type are associated with the financial costs of pinhole leaks. The corrosion prevention choices as well as the plumbing materials depended on the risk of corrosion and cost associated with each option. Previous experiences with pinhole leak impacted the decision for household choices. Faster responses to pinhole leak outbreaks by utility managers and policymakers in terms of advising homeowners on the best ways of responding to leaks would assist homeowners in reducing costs of pinhole leak repairs and associated damages. The second part of this document deals with the debt financing issues. Debt financing decisions are made simultaneously by lenders and borrowers. Since lenders are unable to observe directly the firms’ investment decisions, the banks offer contracts based up on firms’ observable characteristics (i.e. wealth and size) and the prevailing market conditions. When deciding on the financing decisions, firms also take into account the changes in macroeconomic variables in order to lower the cost of borrowing. As a result, the goal for this article is to examine empirically the hypothesis of the effect of the debt determinant as well as the macroeconomic variables on the debt maturity structure. A reduced form of the simultaneous financing decisions model is estimated by employing several OLS estimation methods. The empirical findings offer strong support for firms with few growth options, large, and of low quality having more long-term debt in their capital structure. There was, however, no clear support for the impact of macroeconomic variables on debt maturity as some variables were not statistically significant. / Ph. D.

Made available in DSpace on 2016-06-02T20:09:10Z (GMT). No. of bitstreams: 1 DissMASC.pdf: 3170204 bytes, checksum: 83bd0768232793a648b29a0d4da7f753 (MD5) Previous issue date: 2004-05-06 / Financiadora de Estudos e Projetos / The potable water scarcity afflicts the begging of the 21st Century, being today, one of the main worries of the manhood. This way, it becomes necessary to reduce the per capita consumption. From the actions that promote the racional use of water, the technological ones seems to be , in the most of the cases, the most recomended to reduce the consumption without being necessary radical changes of the users. One of these technologies is the rainwater harvesting. This one erges as an action of good perspectives since it subistitutes the use of potable water in activities where it is not necessary a good quality water, younder, it will reduce the amount of stormwater in the public drainage net, working as a non-structural action of urban drainage. The lack of kwondlege as well a the real advantages that a rainwater system can bring to a builind, is the points to find out about this issue.. At this paper, it seeked to clear this techonolgy up with the study of national and international examples . It also seeked the cistern sizing, getting the best results to technical and economical issues, as well, as procedures to design and to mantain the devices that make part of the system used in this study. Besides that, it studied the changes that would be necessary to build the system, and the possibles changes at the work routine of the construction company. It also studied the financial feasibility of the investiment of this interprisement, checking the real economical advantages that can be get. It is waited that this research contributes to the development of this techonology, contributing to Racional use of water in residential tall buildings. / A escassez de água potável atormenta o início do Século XXI, sendo hoje uma das principais preocupações da humanidade neste século que começa. Dessa forma, surge a necessidade de redução do consumo per capita. Dentre as ações que promovem o uso racional da água, as tecnológicas parecem ser , na maioria dos casos, as mais recomendadas para reduzir o consumo sem que seja necessário mudanças radicais nos hábitos dos usuários. Entre estas, o aproveitamento de água pluvial surge como uma ação de boas perspectivas, pois substitui o uso de água potável onde a qualidade desta não é necessária e, a retirada desta diminuirá a quantidade de volume de água pluvial lançada na rede pública de drenagem, funcionando como uma medida não-estrutural de drenagem urbana. A falta de conhecimento técnico bem como das reais vantagens que um sistema de aproveitamento de água pluvial poderá trazer para uma edificação são as principais incógnitas desse assunto. Neste trabalho buscou-se clarear a tecnologia, com o estudo de diversos casos nacionais e internacionais. Também se buscou realizar o dimensionamento de forma mais correta e econômica, bem como listar procedimentos para elaboração e manutenção de todos os elementos constituintes do sistema utilizado no edifício objeto de estudo. Além disto, verificou-se as possíveis interferências nos processos construtivos, além de alterações das rotinas de trabalho da construtora, além do estudo da viabilidade financeira do empreendimento, verificando as reais vantagens da implantação do sistema neste caso. Espera-se que esse trabalho contribua para o desenvolvimento de uma tecnologia específica para o uso racional de água.