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Sinterização, caracterização e propriedades de compósitos vidro-minerais para uso como revestimentos
(Universidade Federal de São Carlos, 2017-09-06) Santos, Gisele Guimarães dos; Crovace, Murilo Camuri; https://lattes.cnpq.br/2960564171443068; Zanotto, Edgar Dutra; https://lattes.cnpq.br/1055167132036400; https://lattes.cnpq.br/0761705816463042; https://orcid.org/0000-0001-7136-5494
Engineered stones, commonly known in Brazil as quartz surfaces, are materials used as large tiles for application in architecture and interior decoration. These materials consist of about 90% by weight of mineral particles of various shapes (usually quartz, but mica and feldspar are also used) dispersed in a polymer resin matrix. Despite its aesthetic appeal, the use of a polymer matrix leads to low wear resistance, low chemical resistance and great possibility of degradation of the polymer by UV rays and permanent marks by contact with hot objects. Thus, this project objective was the development and optimization of compositions and conditions of thermal treatment, characterization and viability of engineered stones with glass instead of a polymer matrix. Glass-mineral composites containing up to 70% weight of albite, alumina, petalilte and quartz (the rest being recycled window glass) were studied, with special attention in obtaining samples with low porosity. The composites were also characterized in relation to some properties, such as flexural strength, hardness, Kc, water absorption, resistance to thermal shock and resistance to chemical attack. With the exception of Quartz / Glass composites, it was possible to obtain materials of low porosity and diverse competitive properties in relation to other products already available. A composition containing glass and alumina had a flexural strength of 115 MPa and a hardness of 9 GPa; The composite of petalite and glass exhibited greater resistance to thermal shock; The albite and glass composite exhibited better resistance to chemical attack practically unchanged even when in contact with solutions of NaOH 10% (v / v), acetic acid 10% (v / v) and citric acid 3 g / L.
Atividades enzimáticas da celulase, cinéticas e modelagem matemática da decomposição das macrófitas emergentes Hedychium coronarium J König e Typha domingensis Pers
(Universidade Federal de São Carlos, 2017-09-06) Paccagnella, Yeda Carolina; Santino, Marcela Bianchessi da Cunha; https://lattes.cnpq.br/2356641063223397; https://lattes.cnpq.br/6246262052033890
The decomposition of a single macrophyte species may not represent entirely the carbon cycling in aquatic ecosystems, once in these environments several species growth and decay concomitantly. To describe the interaction of decomposition, the temporal variation of particulate organic carbon (POC) of Hedychium coronarium, Typha domingensis and the mixed samples (50% of each species) of these macrophytes were analyzed. Kinetic models were used to verify the temperature and the availability of dissolved oxygen, as regulation factors for the in vitro decomposition. Decomposition bioassays were prepared with dry plant fragments and water samples from the Fazzari Reservoir (47 o 53 ́ 15.80 ́ ́W and 21 o 58 ́ 15.19 ́ ́S). The incubations were maintained under aerobic and anaerobic conditions at 15, 20, 25 and 30 o C. From the chemical point of view, the detritus (single plants and the mixed samples) presented heterogeneous characteristics. The mean values of the labile fraction decay coefficients (k LS ) and the refractory fraction (k R ) of POC were parameterized. The POC temporal variation decay of H. coronarium (Treatment I), T. domingensis (Treatment II) and mixed litters (Treatment III) allowed to observe that, in general, aerobic processes favored the faster POC decay. The increasing temperature influenced the POC loss of mass in the three treatments (I: H. coronarium, II: T. domingensis and III: mixed samples). The Q 10 values in aerobiosis were 1.46, 1.55 and 2.00, and in anaerobiosis were 1.03, 1.26 and 2.09, for Treatments I, II and III, respectively. The anaerobic processes presented higher dissolved organic carbon (DOC) yields than the aerobic. The detritus decay in the Treatments I, II and III was % higher in the aerobic conditions. In general, a trend of pH increases during aerobic and anaerobic decomposition processes was observed. Among the 3 treatments, the mixed samples presented lower electrical conductivity values at 15, 20 and 30 o C, in which T. domingensis presented the highest values, however at 25 o C, the highest values were observed for H. coronarium. A tendency of increased enzymatic activity was observed in H. coronarium (aerobic and anaerobic conditions) and in mixed litters (aerobic conditions) as the temperature increases. The average phosphorus content of the remaining POC found in the aerobic and anaerobic incubations of H. coronarium showed the highest values among the 3 treatments, and T. domingensis litters presented intermediate values, as the temperature increased. The highest phosphorus content was found in mixed litters incubations under anaerobic conditions at 30°C. Interactive responses were evaluated in the mixed litter decomposition. Extrinsic factors (i.e. temperature and dissolved oxygen) and the chemical plants composition influenced the mixed samples decomposition processes, being observed antagonistic effects in aerobic incubations, at all temperatures, and, in anaerobic conditions, antagonistic (15 o C), additive (20 and 25 o C) and synergistic effects (30°C) were observed.
A construção da identidade profissional do professor de Música para a escola de Educação Básica
(Universidade Federal de São Carlos, 2017-09-06) Joly, Maria Carolina Leme; Lima, Emília Freitas de; https://lattes.cnpq.br/5515637339275988; https://lattes.cnpq.br/8669536548912329
This work is the product of a PhD research in Education and focuses on the professional identity of the school’s music teacher. The objectives were: (1) to analyze the identity construction process of the Music teacher, in order to understand the relationships that it establishes with the context of Music Education in Brazilian basic education; (2) understand which are the processes of socialization that influence the construction of the identity of the teacher of Music of basic education; (3) To analyze how different experiences, social relations and contexts influence the identity of Music teachers in basic education. The research question that guided the work was: How is the identity of the music teacher who works in basic school constructed?The key concepts of the research are: Identity, based on the Dubar, Socialization, having Dubar, Berger and Luckman as reference and Culture, based on the productions from Raymond Williams. The methodology is mixed, being bibliographical research, analyzing scientific articles on the subject, and field research, with semi-structured interviews. As data, I analyzed 16 articles from five different countries and interviewed two music teachers, who were admitted to work in the public education system. I concluded with this work that being a musician and being a teacher are two aspects that add up to the professional identity of the Music teacher; that the context, both specific to the classroom and broader: of the city or country in which professionals work, has a strong influence on the formation, consolidation or crisis of the Music teatcher’s identity; and, the recognition and value given by society will open or close the possibilities and potential of musical work in the basic school. The aim of this work is to understand the music teacher’s professional identity in order to contribute with his recognition, his training process and his space of action