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Desenvolvimento de microcantilever funcionalizado com polímero condutor para a detecção de compostos orgânicos voláteis e umidade relativa
(Universidade Federal de São Carlos, 2012-05-31) Steffens, Clarice; Herrmann Júnior, Paulo Sérgio de Paula; https://lattes.cnpq.br/3478230611350302; https://lattes.cnpq.br/8224498867270799
The great interest to develop microcantilevers sensors is due to several desirable properties, in particular the ability to adjust the size and structure, thus increasing the perspectives for the construction of new sensor systems. In this work, we developed functionalized microcantilever sensors with conducting polymers to detect relative humidity, volatile organic compounds and insect pheromones. The development was based on a systematic investigation, since the polymer synthesis and the film formation until the sensing step. For this purpose, we studied two treatments to clean the microcantilevers surfaces (plasma and piranha solution). Also, appropriate ways for the sensors functionalization were evaluated, using spin-coating and thermoelastic probe techniques. The polyaniline solutions were obtained by the in-situ and interfacial synthesis. This way, the doping, morphology and the polymer structure have been investigated by the AFM, UV-Vis, FTIR, diffraction and FE-SEM techniques, and likewise the film properties. It allowed us to optimize the preparation conditions of the polyaniline films on the surface of the microcantilevers sensors to detect relative humidity and volatiles. Also, it was possible to develop sensors with polyaniline thin films, capable to detect 1 ppmv of relative humidity, and this shows that they can be used to measure large limits of detection. Moreover, the functionalized microcantilevers sensors showed a fast response time, repeatability over several cycles and exhibited lifetime longer than 6 months. The coated microcantilevers sensors showed an excellent response to the volatile organic compounds (VOCs), indicating that the sensitive layer was xiv appropriate for detection of these volatiles. The sensitivity of these sensors at VOCs increased with the polarity, thus the methanol compound showed the greatest sensitivity. It was possible to detect and evaluate different concentrations of the pheromone 2-heptanone, at different temperatures. The microcantilever sensors response not only showed an excellent sensitivity, but also a fast response time. It was observed an excellent response to deflection of the microcantilever sensors when exposed to volatile during the banana ripeness.
Análise dos critérios de priorização de projeto junto ao fundo estadual de recursos hídricos do Estado de São Paulo: estudo de caso do Comitê da Bacia Hidrográfica do Tietê-Jacaré
(Universidade Federal de São Carlos, 2012-05-31) Martins, Renata Genova; Salvador, Nemésio Neves Batista; https://lattes.cnpq.br/9930582531600560; https://lattes.cnpq.br/9196368368202528
The State Water Resources Fund of São Paulo (FEHIDRO) was established by the 7.633 State Law, of December 30 of 1991, to give financial support to the hydrographic basins actions. The resources from this fund are distributed in the Water Basis Committees (CBH) every year, each CBH is responsible for finding the way to select the projects. This research aimed to study the criteria and rules for distribution of financial resources in the Water Basis Committee Tietê-Jacaré (CBH-TJ), arising from FEHIDRO, aiming to contribute to its improvement. For develop of this study four stages were performed: Bibliographic Search; Chacterization of study area; Documental Search and survey of opinion. The third stage consisted in a diagnosis of the investments realized with FEHIDRO resources and also the comparative analysis of the adopted criteria to the projects approval in the CBH-TJ and other committees of São Paulo State. The last stage referred to the questionnaires along the keymembers of the committee, where it sought the identification of process failures, difficulties in the projects evaluation and guidelines for solving the problems and/or contributions for the process improvement. The results showed that some criteria adopted by CBH-TJ have failures (lack of information to the score, absence of weighing and subjective criteria which makes difficult the impersonality in the assessments). It was suggested several ways to improve the process (adoption of more technical criteria that reduct the subjective in the assessments, elaboration of specific punctuation score cards according each thematic line, addition of new criteria, increase of the evaluation time of projects and weight attribution for all criteria), which will give support for the improvement of the decisions to be made by CBH-TJ, as well contribute for a better allocation of FEHIDRO public resources.
Cultivo de surubim pintado (Pseudoplatystoma corruscans) e híbrido (P. reticulatum X P. corruscans) em sistema de recirculação de água
(Universidade Federal de São Carlos, 2012-05-31) Miranda, Mário Olindo Tallarico de; Verani, José Roberto; https://lattes.cnpq.br/0053232138684810; https://lattes.cnpq.br/4018340450695188
This study aimed to test a pilot recirculating aquaculture system (RAS) and to evaluate in this system the effects of the stocking density on the production of species of surubim pintado , Pseudoplatystoma corruscans, and its hybrid with P. reticulatum regarding the effect of stocking density and water renewal rate on the hybrid production. The study lasted for 84 days. The physical and chemical conditions in the RAS was evaluated by measuring water consumption (223,6 L/kg of fish produced), temperature (25,8±0,7ºC), dissolved oxygen (5,33±0,04 mg/L O2 in the water inlet to culture tanks), pH (6,75±0,25), total alkalinity (40,0±20,6 mg/L CaCO3), carbon dioxide (16,6±6,1 mg/L CO2), total suspended solids (8,0±4,2 mg/L TSS), total ammonia nitrogen (0,18±0,10 mg/L NH3-N), nitrite (0,163±0,090 mg/L NO2-) and nitrate (58,0±9,7 mg/L NO3-). To evaluate the fish performance, two experiments were conducted simultaneously. In experiment 1, densities of 40, 80 and 120 fish.m-3 (approximately 8.5, 17 and 25.5 kg.m-3) for the pure and the hybrid lineages were tested using a 3 x 2 factorial design (three densities and two lineages). In experiment 2, only the hybrid lineage was used, and three stocking densities were tested: 20, 40 and 60 fish.m-3 (approximately 9, 18 and 27 kg.m-3) and two water renewal rates (1 L/kg.min-1 and 0,5 L/kg.min-1), using a 3 x 2 factorial design (three densities and two water renewal rates). Fish were fed with extruded food (40% crude protein) at a rate of 2.5% of the body weight per day. For both experiments, daily specific growth rate (SGR), final weight, biomass gain, final density, food conversion, final weight and dissolved oxygen levels at the tank outlet are discussed. In experiment 1, both lineages showed to be adapted to the RAS, but the hybrid lineage had a better performance than the pure lineage. In experiment 2, the highest water renewal rate resulted in a better performance, and an increase in density improved the final production.