Petroleum reserves available worldwide are geologically based mainly on sedimentary and carbonate rocks, and the reservoir performance depends on the intrinsic properties of each rock and their response to changes in wettability. Recently, the change in wettability with low-salinity brine has been used to improve the oil recovery, which is an environmentally friendly and low investment, but there is no unanimity about the mechanisms of oil recovery process. Therefore, the aim of this study is to investigate the process involved in the wettability associated with interactions between the surface of powdered reservoir rock samples and the surrounding fluids. The reservoir rock surface (sandstone, calcite and dolomite) was evaluated under three different conditions. The total amount of adsorbed oil on aged samples was twice as high in carbonate rocks as in sandstone. The thermal gravimetric analysis (TGA) for the desorption steps of the organic fraction on dolomite and calcite indicates that the treatment under high brine concentration favored the oil desorption and the opposite result was observed for sandstone. This behavior suggests that carbonate rocks adsorb more strongly the organic phase compared to sandstone. Recently lowsalinity salinity investment Therefore fluids sandstone, sandstone (sandstone conditions TGA (TGA

The objective of the present work was to apply self-organizing feature maps (SOFM) and multilayer perceptron (MLP) to evaluate the protective capacity of tert-butylhydroquinone (TBHQ), butylhydroxyanisole (BHA), and butylhydroxytoluene (BHT) antioxidants against the biodiesel oxidation reaction. For this, the antioxidant concentration and the biodiesel compliance parameters were used as continuous input variables and the type of antioxidant as a categorical. The SOFM proved to be an adequate tool for the classification of biodiesel samples containing antioxidants. The performance of the 5 most active networks of the model ranged from 89 to 99% for training, testing, and validation with an error below 1.42 × 10-4. Statistical tests applied to validate the model showed no significant difference between predicted and experimental values. The global sensitivity analysis showed that the relative protection factor (RPF) contributed with 34.89%, the antioxidant with 31.49%, the induction period with 10.69%, the water content with 6.00%, and the others all together with 16.93% in the construction of the regression models by MLP.

The simultaneous diffusion of inorganic components in the olive pulp in wet brine was modeled based on Fick’s generalized 2nd Law and simulated using the finite element method. The main and crossed diffusion coefficients, the film coefficient and the Biot number were determined, with the application of the simplex optimization method, through the minimization of the percentage errors. The errors between the simulated and experimental data were 5.35% for NaCl and 4.77% for KCl and the adjusted main diffusion coefficients were 0.4358 × 10-12 m2 s-1 for NaCl and 0.5408 × 10-12 m2 s-1 for KCl. The system developed to simulate diffusion allows the control and modulation of the salts content that diffuses through the olive pulp.

Olive samples were subjected to the salting process in brine containing 1196 mol m−3 of NaCl and 402 mol m−3 of KCl. Samples were collected during 60 h and salt concentration values were determined. With the finite element method (FEM) and the minimization of the errors percentage between the simulated and experimental values, the mass transfer coefficients in the film (hm) were obtained, being 1.0072 × 10−8 and 1.2499 × 10−8 for NaCl and KCl, respectively. The salts concentration at the olive/brine interface was simulated by FEM and analyzed via SOFM. A network with 4 × 4 topology and 10000 training epochs was used. It was observed that the influence of the stationary film formed on the surface of the olives during the salting process depends on the position, the salt involved in the diffusion and that the concentration of the salts, at each point, varies according to the immersion time.

Sodium chloride is used in the cheese salting process as it promotes sensory changes and food preservation. However, in excess can cause hypertension problems, and for this reason, it has been partially replaced by potassium chloride. In the present work, Prato cheese was subjected to joint diffusion of NaCl and KCl by immersion in static and stirred brine. The salt concentration values on the cheese surface were determined as a function of time. They were tabulated and presented to the self-organizing map (SOM)-type neural networks and the multilayer perceptron (MLP) for analysis and modeling of the film formed on the surface of the cheese during static and dynamic salting. The SOM network showed that the behavior of the diffusive process, on the surface of the cheese, depends on the analyzed position and that the points in which occupy similar positions, concerning the distance from the edge, have similar behavior. Regression models for NaCl and KCl were significant at the 5% level and can be used for predictive purposes.

The influence of the film formed during the salting of champignon mushrooms with brine containing NaCl and KCl was modeled using the finite elements method (FEM). It was verified that the film formed on the mushroom surface had a greater influence in the static salting since the diffusion of the ions was 7.5-fold smaller in this system than in the stirred salting. The application of self-organizing maps showed that the ions diffusion along the surface of the solid presented a heterogeneous occurrence and depended on the region for both static and stirred salting. A direct relation was observed among the mushroom surface morphology, the salts diffusion behavior, and the film formation. In addition, the film was not completely extinguished in the stirred system, although it has a minimal influence as the film formation is also dependent on the biosolid surface.

The NaCl and KCl diffusion in the film formed on the cheese surface during salting was simulated by the finite element method. The time and salts concentration values on the cheese surface were determined, tabulated, and presented to the multilayer perceptron neural network (MLP) for the regression modeling. The samples were divided into 70, 15 and 15% for training, testing, and validation, respectively. The networks with the best performance showed 5 to 12 hidden layers. The Tukey’s test showed that there was no significant difference, at the 5% level, between the time value used and the mean value modeled for training, testing, and validation for the NaCl. For the KCl, a significant difference was observed only for 2 training samples and 1 test sample. Sensitivity analysis showed that the discrete variable Z, which represents the static and dynamic systems, was the most important in the models’ construction.

Biodiesel is a biofuel produced by the esterification reaction. It is an option to replace fossil fuels, mainly diesel, due to its similar physical and chemical properties. In this research, a mathematical modeling was performed to predict the antioxidant mass to be added in a commercial biodiesel to achieve the minimum oxidative stability provided by the legislation. An equation for each additive was proposed, with the mass of these antioxidants considered as dependent variables and the conformity parameters as independent ones, obtaining multiple regression equations without intercept. The BHA and BHT antioxidants were used. The equations provided were lower at the 5% level and presented determination coefficients (R2) equal to 0.9790 and 0.9770 for the BHA and BHT, respectively, proving their predictability ability and also showing that they can be used to estimate the antioxidant mass to be added in a biodiesel to reach the current regulations.

Biodiesel contains unsaturated methyl esters making it susceptible to oxidation reaction. Among the factors that cause oxidative instability is the contamination by transition metal ions that in small quantities catalyze the oxidation reaction. The objective of this work was to evaluate the relative protection factor of rosemary extract, in biodiesel, in the presence of transition metal ions. Chromatographic analysis and characterization of biodiesel were performed as well as the quantification of total phenolic compounds and extract activity. The ions Cr3+, Co2+ and Fe2+, at a concentration of 3.95 x 10-3 mol L-1, were added to the biodiesel with and without rosemary extract. The samples were submitted to the Rancimat test and to infrared region analyses. The infrared region spectra of the samples with Cr3+ are in accordance with the least catalytic power of this ion under the biodiesel oxidation. Samples with Co2+ ions, without extract, presented bands of aldehydes, and samples with Fe2+ ions show the formation of peroxide radicals, without rosemary extract at 48h. The antioxidant effect of the extract in biodiesel is observed by the reduction of the induction period of the samples. The relative protection factor proved to be a good tool to evaluate its efficiency.

The use of biodiesel as fuel has been presented as a viable alternative in the search for renewable energies. It can be produced from the transesterification reaction of vegetable oils with methanol in the presence of sodium or potassium hydroxide as catalysts. In the present research, the transesterification reaction of soybean oil was modeled considering the three steps of the direct and reverse reactions following a second order general kinetics by the finite element method using the COMSOL Multiphysics® software. The values of rate constants were determined using the simplex optimization method coupled with the desirability functions. The optimized rate constants for the forward reactions were 0.250 × 10−6 (k1f), 1.137 × 10−6 (k2f) and 3.134 × 10−6 (k3f); and for the reverse reactions were 0.202 × 10−6 (k1r), 0.884 × 10−6 (k2r) and 0.219 × 10−6 (k3r) all in m3mol−1s−1. The kinetic model proposed for the reaction can be simulated by the finite element method (FEM) under realistic conditions.

ABSTRACT Surface temperature (Ts) is a determining factor to obtain energy balance parameters, being relevant to understand the influence of this variable on the estimation of evapotranspiration. Thus, the objective of this study was to simulate errors in Ts estimation to verify the consequences of actual evapotranspiration (ETa) estimated by the SAFER (Simple Algorithm for Evapotranspiration Retrieving) model. For this, an image of the Landsat-8 satellite was used to induce errors from 0.2K to 10K in the variable Ts, allowing verifying the consequences in the ETa data. After the estimations of Ts and ETa, the quantitative consequences and dynamics of Ts impact on the ETa data were verified along the different land uses in the study area. The results showed that the precise estimation of Ts is essential to obtain ETa accurately. The image of ETa errors presented the highest relative errors on the surface with exposed soils and with high Ts values. However, the highest residuals of ETa images occurred on the surfaces with milder Ts and higher evapotranspiration rates (irrigated surfaces).

RESUMO Materiais orgânicos submetidos a um processo de digestão anaeróbia, por meio de biodigestor, produzem biofertilizante que pode ser utilizado na agricultura como fonte de nutrientes. O objetivo do presente trabalho foi avaliar o efeito de biofertilizante de dejeto líquido de suínos em atributos químicos do solo, na produtividade e no teor de nutrientes nas folhas e nos grãos de milho. O experimento foi realizado em condições de campo, de novembro de 2012 a abril de 2013. Empregou-se delineamento experimental em blocos ao acaso, com sete tratamentos em quatro repetições. Os tratamentos foram constituídos por doses de biofertilizante de dejeto líquido de suínos, 0; 40; 80; 120; 160; 200 e 240 m3 ha-1, aplicadas na superfície do solo, de uma única vez, no estádio fenológico V2 do milho. Aos 33 dias após a aplicação do biofertilizante foram coletadas, em cada parcela, amostras de solo. A colheita foi realizada aos 129 dias após a semeadura do milho. A aplicação de até 240 m3 ha-1 de biofertilizante de dejeto líquido de suínos, em solo com boas condições de fertilidade, não alterou os atributos químicos do solo e não influenciou na produtividade de milho. O uso de biofertilizante de dejeto líquido de suínos não afetou os teores de nutrientes no tecido foliar nem nos grãos de milho.

ABSTRACT Organic materials subjected to a process of anaerobic digestion in a digester produce biofertilizer that can be used in agriculture as nutrient source. The objective of this study was to evaluate the effect of pig slurry biofertilizer on soil chemical properties and on corn yield and nutrient concentrations in leaves and kernels. The experiment was conducted in the field from November 2012 to April 2013, and was arranged in a randomized block design with seven treatments and four replicates. The treatments consisted of doses of pig slurry biofertilizer (0; 40; 80; 120; 160; 200 and 240 m3 ha-1), applied to the soil surface in a single application, at stage V2 of corn plants. Thirty-three days after biofertilization, soil samples were collected in each plot. Corn was harvested 129 days after sowing. Doses up to 240 m3 ha-1 of pig slurry biofertilizer applied to soil with good fertility did not influence soil chemical properties and corn yield. The use of pig slurry biofertilizer had no detectable effect on nutrient concentrations in corn leaves and kernels.

Resumo:O presente estudo teve como objetivo investigar os efeitos da privação de estímulos (aurais, visuais e cinestésicos) na retroalimentação sensorial durante a preparação inicial de peças para piano por estudantes de diferentes níveis acadêmicos. Estudantes de música (N = 12) da graduação (iniciantes, meio e final de curso) e de pós-graduação (iniciantes de mestrado e um doutorando em final de curso), seguindo um delineamento experimental tipo hierárquico foram submetidos a quatro condições de estudo: (i) Condição A: Decodificação Visual com retroalimentação cinestésica e privação de estímulo auditivo; (ii) Condição B: Decodificação Visual com a privação de estímulo aural e cinestésico (prática mental); (iii) Condição C: Decodificação Aural com retroalimentação cinestésica e privação de estímulo visual da partitura ("tocar a música de ouvido"); Condição D: Decodificação Aural sem retroalimentação cinestésica com a privação de estímulos visual e cinestésico. Os dados obtidos foram analisados quantitativamente e qualitativamente acerca do tempo de prática despendido na realização das tarefas, das estratégias desenvolvidas e dos produtos atingidos pelos participantes em função das condições de estudos propostas. Os resultados revelaram efeito potencial dos níveis acadêmicos sobre o tempo despendido durante a prática nas condições A, C e D, bem como na compreensão musical dos participantes e na qualidade dos registros das performances (produtos) atingidos nas condições A e B. Em termos de estratégias e performances, as condições C e D deram-nos indícios de que a realização destas tarefas parece depender mais de competências acumuladas de cada estudante do que do nível acadêmico os quais estes se inserem.

Abstract:The present study aimed at investigating the effect of stimulus deprivation (aural, visual and kinesthetic) in the sensorial feedback during the initial approach to piano pieces by students belonging to different academic levels. Undergraduate (junior, sophomore and senior) and graduate music student (initial students of master's degree and one student of final doctoral degree) (N = 12), according to a nested experimental design, were submitted to four conditions of study: (i) Condition A: Visual decoding with kinesthetic feedback and privation of aural stimulus; (ii) Condition B: Visual decoding with privation of aural and kinesthetic stimulus (mental practice); (iii) Condition C: Aural decoding with kinesthetic feedback and deprivation of visual stimulus of the score (playing by ear); (iv) Condition D: Aural decoding without kinesthetic feedback with deprivation of visual and kinesthetic stimulus. Data were analyzed quantitatively and qualitatively in terms of time of practice spent for accomplishing the tasks, developed strategies and reached products, according to each condition of study. The results revealed the potential effect of the academic level on the time spent in practice for conditions A, C and D, as well as in the musical understanding and in the quality of attained performance takes (products), for conditions A and B. In terms of strategies and performances, data from conditions C and D suggested the performance under such conditions seem to depend on the cumulative competences of the student rather on the academic level.

Abstract Bromelia includes 66 species, grouped in three subgenera: Bromelia, Distiacanthus and Karatas. The genus is one of the earlier divergent groups within Bromelioideae, a subfamily with innumerable problems of generic delimitation. Considering that few phylogenetic studies have included more than one species of Bromelia, the objectives of this study were to carry out a phylogenetic analysis for the genus, seeking to evaluate its monophyly as well as its subgenera, and to better understand the interspecific evolutionary relationships within the genus and the intergeneric relationships within Bromelioideae. Also included in the analysis were the two species of Fernseea, a genus originally described from a species placed in Bromelia. The phylogenetic analysis was conducted with combined micro- and macromorphological data, including 39 taxa with 116 characters. As in other studies on Bromeliaceae, the clades have low statistical support and many questions regarding the relationships of the groups remain. The circumscription of Bromelia is still uncertain, due to the position of B. irwinii; Fernseea seems to emerge within this genus, as the marority-rule consensus suggests, and the infrageneric categories are debatable because they do not constitute monophyletic groups. However, Bromelia seems to be paraphyletic and, without B. irwinii, the genus can be considered monophyletic. Beginning with the premise that the most recent common ancestor of Bromelioideae appeared first in the southern Andes, Bromelia and Fernseea seems to have dispersed along three biogeographical routes. The present work is an important contribution to understand the evolution and biogeography of the Bromelioideae.

A irrigação é de grande importância para a produção de alimentos, e acredita-se que ela seja responsável por boa parte da produção agrícola mundial, mas é grande consumidora de água doce, principalmente na irrigação por aspersão. O objetivo desta pesquisa é avaliar a redução do custo da energia elétrica para irrigação, por meio de sistema automatizado de controle de velocidade em pivô central instalado em encosta. Para tal, foi dimensionado um pivô central com raio de 56,4 metros com 10 emissores com pressão de serviço de 137,8 kPa, representando uma área irrigada de 1,3 ha, e a lâmina bruta de irrigação adotada foi de 10 mm dia-1. Posteriormente, realizaram-se cálculos para determinar as pressões em cada emissor, para as condições de 0; 10; 20 e 30% de declividade média do terreno. Posteriormente, foi montado um protótipo do pivô central em tamanho reduzido, com 6,3 metros de comprimento, com 10 emissores. Foi utilizado um conjunto motobomba de 2,21 kW (3cv), onde as perdas de cargas em cada emissor eram realizadas por meio de registros inseridos na linha lateral. A automação e o controle de velocidade implementada no protótipo possibilitaram a redução dos gastos em energia elétrica entre 18% e 52%. A automação desenvolvida mostrou-se viável e capaz de responder com agilidade a qualquer mudança de pressão.

Irrigation is of great importance to food production, it is believed that it is responsible for much of the world agricultural production, but appears as a villain in the consumption of fresh water, particularly the sprinkler irrigation. The objective of this research was to evaluate the reduction in the electricity costs for irrigation using automated speed control in central pivot irrigation systems, installed in a slope. For this research, a central pivot was dimensioned with a radius of 56.4 m, 10 emitters, pressure of 137.8 kPa, with a irrigated area of 1.3 ha and an the adopted irrigation depth was 10 mm day-1. Afterwards, calculations were performed to determine the pressures at each emitter to the conditions of 0, 10, 20 and30% of average land slope. A mathematical modeling was done, where the hydraulic calculations were made for these conditions. It was later mounted a prototype central pivot in small size with 6.3 long with 10emitters. It was used a motor pump set with 2.21 kW (3 hp), and the pressure drop in each emitter was done by adding flow controller on the lateral line. The automation and speed control implemented in the prototype enabled the reduction of electricity costs from 18% to 52%. The automation developed show to be viable and able to respond quickly to any pressure change.