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Desenvolvimento de protótipo de sensor de umidade cerâmico
(Universidade Federal de São Carlos, 2012-08-24) Ito, Amadeu Rodrigues Pereira; Souza, Dulcina Maria Pinatti Ferreira de; https://lattes.cnpq.br/4100119317525940; https://lattes.cnpq.br/4941893403738344
Humidity sensor is a special type of gas sensor which is sensitive only to H2O molecules. It has a large variety of applications in industrial, household and agricultural equipments. Humidity ceramic sensors have been considered interesting due to their chemical and thermal stability. The lack of a national manufacturer of humidity sensors was the main motivation to accomplish this master thesis, whose objective was to develop a prototype of resistive ceramic humidity sensor. The objective was reached using Mn doped-MgAl2O4 powder, forming thin plates (650 a 750 μm) through tape casting process, appropriate sintering to obtain proper microstructure and the performance characterization of sintered plates as humidity sensor, especially with regard to sensibility and reproducibility. The tape casting process was successful for providing plates with excellent sensibility in the range 20-90% relative humidity and the response time of 120 and 20 seconds in the adsorption and desorption steps respectively. The correlation between the good performance and the porosity was established through the detailed interpretation of impedance spectra measured at several levels of humidity. Simultaneously to the porous plate preparation, it was developed a microcontrolled electronic transducer circuit with firmware written in C, which allows the immediate use of the electric signal produced by the humidity sensitive plate by a variety of equipments already available in the market. At the final step, the humidity sensor prototype was assembled through the insertion of the humidity sensitive plate, appropriately covered with silver electrode, to the electronic system.
Zoneamento (geo)ambiental analítico da microbacia do Córrego do Rosário (Descalvado, SP)
(Universidade Federal de São Carlos, 2012-08-24) Inêz, Eliezer Bernardes; Lorandi, Reinaldo; https://lattes.cnpq.br/7794241793056671; https://lattes.cnpq.br/2337238348941685
Adopting a river basin as a landscape management unit constitutes a major achievement in planning and management due to socio-environmental interactions and their unfoldings that take place in this area. Among the variety of environmental planning and management tools used in river basin contexts, (geo)environmental zoning is noteworthy in that it helps decision makers and aims at reconciling socio-economic development with environmental quality. Along these lines, the purpose of this study focused on the microbasin of the Rosário stream in Descalvado, SP, Brazil was to present an analytical (geo)environmental zoning proposal generated from a set of thematic mapping documents at a 1:10000 scale, field studies, and geo-technologies that seeks to analyze capacities and susceptibilities of this microbasin terrain in the face of urban occupation. Thus, the findings of this study can serve as a basis for discussion and construction of public policies capable of guiding a right and proper local urban expansion process.
Análise do controle autonômico cardíaco e do metabolismo muscular durante o exercício descontínuo dinâmico e resistido em homens jovens e idosos
(Universidade Federal de São Carlos, 2012-08-24) Simões, Rodrigo Polaquini; Silva, Audrey Borghi; https://lattes.cnpq.br/4855616925791895; https://lattes.cnpq.br/2731345085062145
The thesis consisted of three studies described below. Study I, which aimed to investigate the effect of aging on kinetic responses of heart rate (HR) and oxygen consumption (VO2) during rest-exercise (ontransient) and exercise-recovery transitions (off-transient), and to investigate the influence of exercise intensity (mild and moderate) on the kinetic parameters of these variables. 28 apparently healthy men were evaluated, and 14 constituted the young group (YG) and 14 the elderly group (EG). The evaluation consisted of applying an incremental exercise testing of ramp protocol on cycle-ergometer (IET-R) to determine the maximum power (MP) and discontinuous exercise test on a cycle ergometer (DET-C), which started with an initial power load of 10% of MP with subsequent increase of 10% until exhaustion. Were recorded ventilatory and metabolic variables, the HR and blood lactate at rest and during exercise. The lactate threshold (LT) was closed between the groups (approximately 30% of MP). The EG showed higher values of the kinetic responses, both on and off transitions of HR and VO2 (p<0.05), and the values were higher in moderate compared to mild in YG (p<0.05). We conclude that the elderly have slower kinetic responses of HR and VO2 in relation to young and that at moderate intensity; the kinetic responses were slower in relation to mild intensity in young. Following, the study II aimed to investigate the behavior of the heart rate variability (HRV) responses during a discontinuous resistance exercise (RE) protocol and check whether they agree with the blood lactate responses in the determination of anaerobic threshold (AT) in apparently healthy young and elderly. For this proposal, in the same volunteers in the study I, was applied the test of one repetition maximum (1RM) on the leg press 45º and the discontinuous exercise test on the leg press 45 (DET-L), initiated in 10% of 1RM subsequent increments of 10% until exhaustion, and the HR and blood lactate were obtained at rest and during exercise. The AT was determined at approximately 30% of 1RM in both groups and both methods of analysis (blood lactate and HRV), the HRV index decreased with increasing load and stabilized from the load corresponding to AT in both groups, additionally the blood lactate remained practically stable until the load of AT, and increased significantly after this intensity. The EG had lower HRV values in lower loads of AT, and lower values of HR and blood lactate in loads above of AT in relation to the YG. We conclude that the HRV responses to determine the AT are according to blood lactate, and that the increase in load during the discontinuous RE promoted gradual vagal withdrawal followed by sympathetic activation in both young and the elderly, however, these responses are attenuated with the aging process. Finally, the study III, aimed to determine the AT during discontinuous dynamic and resistance exercise protocol by analyzing blood lactate and HRV in healthy older adults, comparing the cardiovascular, metabolic and autonomic variables between these two exercise modalities. We evaluated the elderly group of individuals during the tests: IET-R, DET-C, 1RM and DET-L. The AT within about 30% of maximum intensity in both the DET-C and DET-L by both methods (blood lactate and HRV). There were no differences in HRV variables between the modalities of exercise and a significant increase in systolic blood pressure and blood lactate after AT load in the DET-L. We conclude that HRV was effective in determining the AT and that the parasympathetic modulation responses were similar between dynamic and resistance exercise.
Avaliação quali-quantitativa do fitoplâncton presente em reservatório de sistema de aproveitamento de água pluvial para irrigação
(Universidade Federal de São Carlos, 2012-08-24) Corrêa, Thais Helena Prado; Moruzzi, Rodrigo Braga; https://lattes.cnpq.br/9408665052901005; https://lattes.cnpq.br/0668892738076635
The use of rainwater can be an effective alternative to minimize the use of water sources. Within this perspective, stormwater play a key role in planning and sustainable management of water resources as a substitute for the use of water for agricultural purposes, irrigation, residential uses such as watering flowerbed and garden, cleaning floors, sidewalks and playground and car wash. Agriculture is the major user of water in the world, according to the World Resources Institute, UN agriculture uses 70% of existing drinking water. In Brazil, 88% of drinking water is used by agriculture and 5% of Brazilian crops are irrigated and 55% of farmers use archaic methods that lose more than half of the water used. Thus, alternative techniques of water management for irrigation must be proposed and implemented to mitigate the conflicts generated by the deficiency of water considering the use of rainwater as part of a broader activity, related to the expansion of water supply. Therefore, one should consider rainwater as an alternative source to conventional sources and it should investigate the potential qualitative and quantitative agreement with the intended uses. In this work the intended use is irrigation of vegetable crops for research on sustainable agricultural management techniques were therefore investigated the existence of species of phytoplankton and physical and chemical analyzes made reservoir built in the Research Center of the city-Ipeúna-SP.
Estudos cristaloquímicos e teóricos de derivados do decahidrofenantreno
(Universidade Federal de São Carlos, 2012-08-24) Machado, André Tivagus Lousada; Schpector, Júlio Zukerman; https://lattes.cnpq.br/4252331837170383; https://lattes.cnpq.br/3662422395254441
This work is a contribution to the study of the crystal, molecular and supramolecular structures as well as the conformation in vacuum of decahydrophenantrene derivatives. (4aS,4bR,7R,10aS)-3,7-Dimethyl-10a- (propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-decahydrophenanthrene-1,4-dione (Compound 1) In this compound, C19H26O2, the A ring adopts a chair conformation, whereas the B and C rings both adopt distorted half-chair conformations with the quaternary C atom common to both rings lying 0.577 (3) and 0.648 (3) Å out of the approximate plane defined by the remaining five C atoms (r.m.s.deviations = 0.1386 and 0.1156 Å for the B and C rings, respectively). Molecules are assembled in the crystal through C—H…O interactions involving both carbonyl O atoms, which lead to supramolecular chains aligned along the b axis. (4R,4aS,4bS,7R,10aR )-4-Hydroxy-4a,7-dimethyl-2-(propan-2- yl)-1,4,4a,4b,5,6,7,8,10,10a-decahydrophenanthren-1-one (Compound 2) In this compound, C19H28O2, the A ring adopts a chair conformation, and each of the B and C rings adopts a distorted half-chair conformation with the methine C atom in the CH2C(H)C( O) residue, common to both rings, lying 0.6397 (19) and 0.6328 (18) Å out of the approximate plane defined by the remaining five C atoms (r.m.s. deviations = 0.0791 and 0.0901 Å for rings B and C, respectively). Helical supramolecular chains along the a axis mediated by hydroxy– carbonyl O—H…O hydrogen bonds feature in the crystal packing. (4R,4aS,4bS,5R,10aR)-4-Hydroxy-4a,5-dimethyl-2-(propan-2-yl)- 1,4,4a,4b,5,6,7,8,10,10a-decahydrophenanthren-1-one (Compound 3) In this compound, C19H28O2, the A ring adopts a chair conformation. Both the B and C rings adopt envelope conformations with the C atoms common to both rings and adjacent to the carbonyl and hydroxyl groups, respectively, lying 0.604 (3) and 0.634 (3) Å out of the mean planes defined by the remaining five C atoms of rings B and C, respectively (r.m.s. deviations = 0.0100 and 0.0157 Å, respectively). The formation of linear supramolecular chains along the a axis mediated by hydroxy-O—H…O(carbonyl) hydrogen bonds is the most prominent feature of the crystal packing. The calculated and crystallographic structures are shown to be similar so that, in this case, the intermolecular interactions and consequently the crystal packing has almost no influence on the molecular conformation.