Influência da adição do NaCl e KCl em sistemas de pastas contendo sílica para poços de petróleo em zonas evaporíticas e carbonáticas

One of the major challenges faced nowadays by oil companies is the exploration of pre-salt basins. Thick salt layers were formed in remote ages as a consequence of the evaporation of sea water containing high concentrations of NaCl and KCl. Deep reservoirs can be found below salt formations that prevent the outflow of oil, thus improving the success in oil prospection. The slurries used in the cement operations of salt layers must be adequate to the properties of those specific formations. At the same time, their resulting properties are highly affected by the contamination of salt in the fresh state. It is t herefore important to address the effects of the presence of salt in the cement slurries in order to assure that the well sheath is able to fulfill its main role to provide zonal isolation and mechanical stability. In this scenario, the objective of the present thesis work was to evaluate the effect of the presence of NaCl and KCl premixed with cement and 40% silica flour on the behavior of cement slurries. Their effect in the presence of CO2 was also investigated. The rheological behavior of slurries containing NaCl and KCl was evaluated along with their mechanical strength. Thermal and microstructural tests were also carried out. The results revealed that the presence of NaCl and KCl affected the pozzolanic activity of silica flour, reducing the strength of the hardened slurries containing salt. Friedel´s salt was formed as a result of the bonding between free Cl- and tricalcium aluminate. The presence of CO2 also contributed to the degradation of the slurries as a result of a process of carbonation/bicarbonataion

Hidrocarbonetos policíclicos aromáticos em sedimentos de fundo do estuário do rio Potengi, região da grande Natal (RN): implicações ambientais

Estuaries are environments prone to the input of chemical pollutants of various kinds and origins, including polycyclic aromatic hydrocarbons (PAHs). Anthropogenic PAHs may have two possible sources: pyrolytic (with four or more aromatic rings and low degree of alkylation) and petrogenic (with two and three aromatic rings and high degree of alkylation). This study aimed to evaluate the levels, distribution and possible sources of polycyclic aromatic hydrocarbons in the estuary of the Potengi river, Natal, Brazil. Samples of bottom sediments were collected in the final 12 km of the estuary until its mouth to the sea, where the urbanization of the Great Natal is more concentrated. Sampling was performed on 12 cross sections, with three stations each, totaling 36 samples, identified as T1 to T36. The non alkylated and alkylated PAHs were analyzed by gas chromatography coupled to mass spectrometry (GC / MS). PAHs were detected in all 36 stations with total concentration on each varying 174-109407 ng g-1. These values are comparable to those of several estuarine regions worldwide with high anthropogenic influence, suggesting the record of diffuse contamination installed in the estuary. PAHs profiles were similar for most stations. In 32 of the 36 stations, low molecular weight PAHs (with 2 and 3 ring: naphthalene, phenanthrene and their alkylated homologues) prevailed, which ranged from 54% to 100% of the total PAH, indicating that leaks, spills and combustion fuels are the dominant source of PAH pollution in the estuary. The level of contamination by PAHs in most stations suggests that there is potential risk of occasional adverse biological effects, but in some stations adverse impacts on the biota may occur frequently. The diagnostic ratios could differentiate sources of PAHs in sediments of the estuary, which were divided into three groups: petrogenic, pyrolytic and mixing of sources. The urban concentration of the Great Natal and the various industrial activities associated with it can be blamed as potential sources of PAHs in bottom sediments of the estuary studied. The data presented highlight the need to control the causes of existing pollution in the estuary

I. Synthetic Studies Toward the Total Synthesis of Polycyclic Natural Products – Communesin F, Perophoramidine and Ineleganolide. II. Nickel Catalyzed Intramolecular C–O Bond Formation

Expedient synthetic approaches to the highly functionalized polycyclic alkaloids communesin F and perophoramidine are described using a unified approach featuring a key decarboxylative allylic alkylation to access a crucial and highly congested 3,3-disubstituted oxindole. Described are two distinct, stereoselective alkylations that produce structures in divergent diastereomeric series possessing the critical vicinal all-carbon quaternary centers needed for each synthesis. Synthetic studies toward these challenging core structures have revealed a number of unanticipated modes of reactivity inherent to these complex alkaloid scaffolds. Finally, a previously unknown mild and efficient deprotection protocol for the o-nitrobenzyl group is disclosed – this serendipitous discovery permitted a concise endgame for the formal syntheses of both communesin F and perophoramidine.

In addition, the atroposelective synthesis of PINAP ligands has been accomplished via a palladium-catalyzed C–P coupling process through dynamic kinetic resolution. These catalytic conditions allow access to a wide variety of alkoxy- and benzyloxy-substituted PINAP ligands in high enantiomeric excess.

An efficient and exceptionally mild intramolecular nickel-catalyzed carbon–oxygen bond-forming reaction between vinyl halides and primary, secondary, and tertiary alcohols has been achieved. This operationally simple method allows direct access to cyclic vinyl ethers in high yields in a single step.

Finally, synthetic studies toward polycyclic ineleganolide are described. The entire fragmented carbon framework has been constructed from this work. Highly (Z)-selective olefination was achieved by the method by the Ando group.

Os estudantes e sua representação social do Curso Técnico Integrado em Artesanato na modalidade PROEJA do Instituto Federal de Brasília – Campus Taguatinga

Dissertação apresentada para obtenção do grau de Mestre em Educação Social e Intervenção Comunitária

Predição da criatividade e saúde mental

A criatividade tem sido mencionada desde há muito tempo pela literatura. A forma de a conceptualizar tem dependido em muito dos investigadores e da sua visão sobre o que é criatividade, porém as suas potencialidades têm tomado cada vez mais interesse pela comunidade científica. Os seus benefícios estendem-se a diversas áreas da vida humana, como sentimentos de satisfação, bem-estar e saúde mental. A investigação aqui apresentada procura encontrar modelos preditivos de comportamentos criativos, pressupondo que estes poderão ser de grande auxílio para o desenvolvimento de um melhor bem-estar psicológico. Assim a investigação comportou o uso de quatro variáveis: a pessoa, o processo, o produto e o ambiente criativo. A amostra contou com 215 estudantes universitários e os resultados revelaram o encontro de quatro modelos preditivos de comportamentos criativos, com uma maior ênfase nas artes visuais e manuais. Conclui-se com a ideia de que a predição de produtos criativos é possível e que tal poderá ser preponderante para um bom desenvolvimento da saúde mental.

Os estudantes e sua representação social do Curso Técnico Integrado em Artesanato na modalidade PROEJA do Instituto Federal de Brasília – Campus Taguatinga

Dissertação apresentada para obtenção do grau de Mestre em Educação Social e Intervenção Comunitária

South Carolina’s Creative Cluster : A Catalyst for Economic Development

This report presents results from a study of the creative economy associated with the arts, design, crafts and related activities in South Carolina. As this report will show, these creative individuals and enterprises exert a strong impact on the state’s economic base. Like other drivers of the regional economy, this creative activity revolves around a cluster, or a set of interrelated industries, that thrive in tandem. Along with manufacturing and agriculture, the creative cluster is a catalyst for state and local economic development. The report presents results from an analysis of the South Carolina creative cluster based on 2008 data. For the first time, this report provides a comprehensive summary of the creative economic footprint in South Carolina.

Exploration du travail d’une classe en réseau sur un objet partagé en situation d’arts plastiques

Cette étude s’est déroulée dans le contexte de l’École en réseau au Québec. Une classe du primaire a utilisé un espace numérique collaboratif (Knowledge Forum) pour la réalisation d’activités d’éducation artistique, soit l’appréciation d’un corpus d’oeuvres et la création d’un objet d’art. La progression du discours écrit relativement à ces deux objets de partage a été étudiée. Nos résultats montrent que les élèves ont réussi à faire progresser leurs contributions sur les deux objets partagés. En interagissant entre eux, ils ont créé des artéfacts de connaissances partagées et développé un langage artistique propre. À la suite de nos constats, des implications pédagogiques ont été formulées pour d’encourager la participation des élèves lors d’activités d’éducation artistique au moyen d’outils numériques qui soutiennent la collaboration.

Predição da criatividade e saúde mental

A criatividade tem sido mencionada desde há muito tempo pela literatura. A forma de a conceptualizar tem dependido em muito dos investigadores e da sua visão sobre o que é criatividade, porém as suas potencialidades têm tomado cada vez mais interesse pela comunidade científica. Os seus benefícios estendem-se a diversas áreas da vida humana, como sentimentos de satisfação, bem-estar e saúde mental. A investigação aqui apresentada procura encontrar modelos preditivos de comportamentos criativos, pressupondo que estes poderão ser de grande auxílio para o desenvolvimento de um melhor bem-estar psicológico. Assim a investigação comportou o uso de quatro variáveis: a pessoa, o processo, o produto e o ambiente criativo. A amostra contou com 215 estudantes universitários e os resultados revelaram o encontro de quatro modelos preditivos de comportamentos criativos, com uma maior ênfase nas artes visuais e manuais. Conclui-se com a ideia de que a predição de produtos criativos é possível e que tal poderá ser preponderante para um bom desenvolvimento da saúde mental.