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Cultivo heterotrófico de Aphanothece microscopica Nägeli e Chlorella vulgaris em diferentes fontes de carbono e em vinhaça
(Universidade Federal de São Carlos, 2012-03-08) Bonini, Monica de Albuquerque; Bastos, Reinaldo Gaspar; https://lattes.cnpq.br/9329363278429665; https://lattes.cnpq.br/5490287339979298
ABSTRACT Microalgae include both algae Chlorophycea and cyanobacteria. These organisms have attracted interest due to its versatile metabolism, since some strains have, additionaly to photosynthetic metabolism, hability to grow in the dark by the consumption of simple organic molecules, such as glucose, acetate and glycerol. This hability suggests the application of these microorganisms in several areas, such as biological treatment of agroindustrial wastewater, aiming the removal of nutrients and organic matter. São Paulo/Brazil is one of the main producers of ethanol from sugarcane, generating a considerable amount of vinasse. Vinasse represents the main wastewater from de sugarcane agroindustry, being usually applied as fertigation in sugarcane crops. In this context, this study aimed to evaluate the heterotrophic growth of cyanobacterium Aphanothece microscopica Nägeli and the chlorophyceae Chorella vulgaris in synthetic culture media supplemented with organic carbon source and in vinasse, aiming to produce biomass and application it in wastewater treatment. Mixotrophic cultures were conducted to select the optimal concentration of organic substrate for the growth of microalgae, which were evaluated in heterotrophic cultures. Additionally, experiments have been conducted with pre-treated vinasse, evaluating the COD removal and the glucose and potassium incorporation. By the mixotrophic tests was selected the optimal concentrations of 25 and 12.5 g.L-1 glucose, 0.5 and 1.25 g.L-1 potassium acetate and 0.46 and 0.92 g.L-1 glycerol as ideal for the cultivation of Aphanothece microscopica Nägeli and Chlorella vulgaris, respectively, which reflected on the maximum specific growth rate between 0.0072 and 0.043 h-1. In the heterotrophic cultures the maximum specific growth rate was greater or equal to both microalgae in all carbon sources, with reduction between 30.4 and 90% of the initial concentrations of substrates. The experiments demonstrated possibility to use vinasse as culture media for both microalgae, especially Aphanothece microscopica Nägeli. In this conditions, results indicated the maximum removals of glucose (55.5%), COD (60.8%) and potassium (13%) by the cianobacterium, and 83.7% of glucose, 25% of COD and 13.8% of potassium by Chlorella vulgaris. The results suggest the heterotrophic metabolism for both microorganisms, pointing an interesting alternative to use of wastewater as culture media to produce high-value biomass from a low-cost way.
Análise da escoabilidade de pós
(Universidade Federal de São Carlos, 2012-03-08) Campos, Milene Minniti de; Ferreira, Maria do Carmo; https://lattes.cnpq.br/7070885875161111; https://lattes.cnpq.br/8281708881484887
There are many industries which use powders somewhere in their production process, such as: food, pharmaceuticals, ceramics, cement and fertilizer industries. The knowledge of properties associated with the flowability of these materials is important, since the characteristics of the powders can go through amendments in processing. Thus, the evaluation of indexes of flowability and the identification of main factors which influence the powders flowability play an important role in the operation and design of industrial devices. The objective of this study was to evaluate the flowability properties of organic and inorganic powders, as well as analyze which factors interfered in these properties. The organic materials were represented by whole and skim milk powders, while alumina and ceramic powder were selected for the assessment of inorganic materials. The physical characterizations carried out were: display materials morphology at SEM (Scanning Electron Microscopy), size distribution, particle density, initial moisture content, aerated bulk density and tapped bulk density. The measured materials flowability properties were: angle of internal friction, effective angle of internal friction, angle of wall (galvanized steel) friction and flow index, all of them determined by Jenike's direct shear cell, Hausner ratio obtained from the values of tapped and aerated bulk densities; angle of repose, determined through the dropping of powder in an acrylic surface. In general, the results obtained, considering all methodologies employed for the determination of materials flowability, demonstrated that alumina, ceramic powder and whole milk powder, if compared to skim milk powder, presented lower indexes of flowability. If these materials were stored in silos made of galvanized steel, alumina and ceramic powder flowability would be more difficult than that of skim and whole milk powders. Thus, the results showed that the material physical properties interfere in powders flowability. The skim milk powder flowed more easily than whole milk powder, because higher fat content and smaller average particle size of whole milk powder decreased the flowability of this material in comparison to the skim milk powder. Likewise, despite they have similar composition, alumina presented lower flowability that ceramic powder, because this powder had larger average particle size and the powder presented fewer agglomerated particles.
Estudo sobre a ictiofauna do Rio Cabeça, um tributário do Rio Corumbataí com nascentes nas cuestas basalticas do estado de São Paulo
(Universidade Federal de São Carlos, 2012-03-08) Cardoso, Rodrigo Torres; Garavello, Júlio César; https://lattes.cnpq.br/2778105126670170; https://lattes.cnpq.br/8249557280995807
This study investigates the composition and distribution of fish species from Rio Cabeça, a tributary of Rio Corumbataí basin. Fish samples and physical data were monthly collected at four regular sampling sites and during 12 months, thorough the channel of Rio Cabeça and on five additional collection sites. From the physical data, width, depth and water velocity (in m/s) of the river were obtained. The fish collections were made with help of: gill net, trawl net, other hand net and sieve. Species richness and abundance were designed thorough the constancy of occurrence of the species; the Jaccard similarity analysis of rarefaction; the species accumulation curve and a descriptive analysis of the collecting sites. The sampling sites showed physical characteristics as: Site 1, narrow but deep and with rapid waters. Site 2, wider and shallower and with more water spread. Site 3, mostly broad and deeper. Site 4, also broad and shallow, but containing rapids and fast waters. The samples include 4.532 fish specimens belonging to six orders, 17 families and 65 species. Site 4, showed the best richness and abundance, and the other three sites revealed to be more or less similar. In terms of constancy the site 4 had the highest percentage of occasional species, while the other three sites had the highest percentage of regular species. The analysis of rarefaction had shown a greater richness of species at site 4 and lower species richness at remaining sites. The species accumulation curve shown that a considerable proportion of fish species is present in this river as represented in this study. The Jaccard similarity analysis shown significant differences in the species composition through the four collecting sites. The results and the discussion suggest that the basaltic Corumbataí mountain formation may interfere with the distribution, composition and richness of the ichthyofauna. On the other hand, the Rio Cabeça with 65 fish species is an important tributary of the Rio Corumbataí. Finnaly this study outcome the necessity of more attention to ichthyofauna conservation at waterfall environments, where the specimens are exposed to illegal fisheries.
Estudo da secagem de sementes de embaúba em leito fluidizado
(Universidade Federal de São Carlos, 2012-03-08) Corrêa, Luciano Jacob; Sartori, Dermeval José Mazzini; https://lattes.cnpq.br/6654974812569635
Due to the importance of conservation of ecosystems and having Cecropia glaziovi.S as a pioneer species of the Tropical Forests, this plant becomes indispensable in reforestation areas altered wild. The drying operation is fundamental in the improvement of seeds, since it is not a seed recalcitrant. There is currently interest in studies of convective drying of the seeds on bed furniture, as in previous search has been shown to occur in fixed bed preferential channels and agglomerations of particles. The objective of this work is to study the fluidized bed capable of carrying out the drying of seed of native plants with the maintenance of physical and physiological properties. The comparison between the methods of decomposition and scraping the inflorescences wet and dry extraction showed that the wet method is more suitable for this kind of seed. The fluid dynamics of the contact between the seed and the fluid was drawn from measurements of pressure drop and air flow rates increasing and decreasing the bed. Using the method of SOGAB, demonstrated the uniformity of velocity and temperature in the entrance region of the measuring cell. The analyze the fluid allowed to obtain the information on the fluidisation characteristics curves, while the drying tests enabled the knowledge of the effects of temperature and velocity of the drying air on the properties of the seeds. The data obtained were compared with empirical equations and the resulting semi-empirical literature. Since the Page equation is analyzed between the equations that best represents the experimental data according to statistical criteria adopted. Assessment of germination, regardless of substrates, which are germitest paper germibox tanks and soil showed that the seeds are suitable for replanting. It was possible to obtain, after drying, seed with adequate humidity values for the storage and physiological qualities contribute to the perpetuation of these embryos and dissemination of higher plants in nature.
Análise do ciclo de vida energético de projeto de habitação de interesse social concebido em light steel framing
(Universidade Federal de São Carlos, 2012-03-08) Carminatti Júnior, Riberto; Paliari, José Carlos; https://lattes.cnpq.br/9387796929252598; https://lattes.cnpq.br/7770833599788902
The construction industry in Brazil has great importance both socially and economically, but generates more than 50% of municipal solid waste and consuming large quantities of raw materials, energy and water. Thus the sector is strategic under the environmental point of view, since small changes in their processes cause the reduction of environmental impacts. To meet the current housing shortage, many building systems are being employed in the country, among which, the Light Steel Framing (LSF), which consists of a rational building system, and industrial productivity. The aim of this study was to simulate the amount of embodied energy original (EEi) of a standard project aimed at social housing using the LSF as a constructive system, applying the concepts of Life Cycle Analysis of Energy (ACVE). To achieve this goal initially was held to review the literature on sustainability, and LSF construction system ACVE. Following the adjustment was made for a project for social housing in structural masonry designed to LSF. From the specifications for materials and components, their respective values of the quantitative EEi and held the simulation of the quantity of EEi considering three scenarios: project conceived in structural masonry concrete block, masonry, structural ceramic blocks and LSF. Comparing the results of three simulations, it was concluded that the project designed masonry structural ceramic blocks showed the lowest absolute value of the EEi in relation to other systems simulated (117.6 GJ and 3.0 GJ / m² ), with the LSF presented an intermediate value (154.3 GJ and 3.9 GJ / m²), but very close to the masonry of ceramic blocks, while designed masonry concrete blocks had a higher value (262 , 0 GJ and 6.6 GJ / m²), largely due to the high value of IAS adopted for the concrete. It is noteworthy that these results should not be extrapolated as EE values were used for materials and components used in these construction systems referenced in the international literature, which indicates the need to build a national database about.
Desenvolvimento de blendas poliméricas policarbonato/ poli (Tereftalato de Butileno) (PC/PBT) compatibilizadas e nanoestruturadas
(Universidade Federal de São Carlos, 2012-03-08) Laurindo, Vanessa; Hage Júnior, Elias; https://lattes.cnpq.br/1240692926327687; https://lattes.cnpq.br/8930068830121454
The evaluation of addition of a random copolymer as compatibilizing and his effect in obtaining nanostructured morphology in blends composed by PC as matrix and PBT as dispersed phase, were investigated. The copolymercompatibilizer was produced by reactive mixture, in a torque rheometer, of the components of blend PC/PBT (50/50%wt) in the presence of different concentrations of the catalyst TnBT (1000 and 2000 ppm) and different mixing times (10 and 30 minutes). The characterization of thermal and chemicals properties by DSC, FTIR and 1HNMR showed evidences of the occurrence of transesterification reactions between the blends components for all systems studied. However, formation of the random copolymer was confirmed only for the system with addition of 2000 ppm of the catalyst, subjected to different mixing times. To minimize the effects of degradation reactions in the random copolymer formed, was selected use as compatibilizer to obtain nanostructured blends, the copolymer obtained after 10 minutes of mixing. To evaluating effect of the copolymer-compatibilizer in obtain a nanostructured morphology, were prepared blends PC/PBT (95/5%wt) with addition of 0, 1, 3 and 5% wt of copolymer and by the thermal analysis by DSC and DMTA was observed the existence of a partial miscibility, restricted to the amorphous phase, between the components of the blends PC/PBT studied. Morphological analysis by TEM revealed to obtain a dispersed phase nanostructured for the blend with addition of 3%wt of compatibilizing. The effect of random copolymer as compatibilizing agent for the blends studied was also demonstrated by characterization of the mechanical properties of tensile and impact.