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Recuperação de fosfolipídeos residuais do farelo desengordurado de soja
(Universidade Federal de São Carlos, 2014-08-07) Siqueira, Paula Fernandes de; Tardioli, Paulo Waldir; https://lattes.cnpq.br/0808991927126468; https://orcid.org/0000-0002-5011-9881; Giordano, Raquel de Lima Camargo; https://lattes.cnpq.br/9695542424889786; https://orcid.org/0000-0002-8313-9002; https://lattes.cnpq.br/6192564133849711; https://orcid.org/0000-0002-7835-9780
In soybean processing industry, oil extraction with hexane generates defatted meal. Next, soybean protein concentrate (SPC) production from the defatted meal by using ethanol solution generates alcoholic micelle as a byproduct. Following stages of ethanol recovery and concentration of that micelle, a sugared product called soybean molasses is produced. Observations of the presence of a viscous fraction (precipitate) in storage tanks of alcoholic micelle were the reason of this study which aimed at recovery of that phospholipids-rich material, main components of lecithin which presents high value in the market of soybean derivatives. So, the work was divided into three stages: development of technology, laboratory testing, and industrial testing. First of all, an analytical method by liquid chromatography for quantification of phospholipids was developed and validated. Next, assays in laboratory scale were worked out in order to evaluate the efficiency of phospholipids extraction from soybean defatted meal in different solvent systems, besides studying the behavior of each phospholipid in the system of solvent selected and the correlation between phospholipid extraction and protein concentration. The extraction process of residual phospholipids from defatted meal was studied by using varied mixtures of solvents. The following yields were obtained, in % (m phospholipids/m meal): 0.42 ± 0.01 (Hexane), 1.44 + 0.03 (Hexane: Ethanol 4:1), 1.08 ± 0.07 (Chloroform: Methanol 2:1), 1.48 ± 0.01 (Ethanol 75% v/v). As the extraction with 75% ethanol was the most efficient, the ethanol system : water was more deeply studied, because that is also the system used in SPC production. By varying the ethanol concentration, the best condition of extraction (70% v/v ethanol) enabled a recovery of 1.53 ± 0.02% (m/m) of phospholipids in the extract and 71.69% (m/m) of protein in solid fraction. Solubility of phospholipids was also tested in aqueous ethanol and remained between 0.499 g/L in 50% ethanol (v/v) at 25oC and 6.225 g/L in 90% (v/v) ethanol at 75oC. At last, industrial tests were carried out, in order to observe the production of material from actual conditions of process. Tests carried out were on micelle centrifugation and gum recovery (lecithin), and on drying of material obtained in continuous drier, besides analytical and commercial assays of the product, pure or as component of chocolates. It was possible to obtain a lecithin within commercial specifications, with high quality, and a yield of recovery of approximately 18.7 g lecithin to each kilogram of dried defatted meal. Results from this work showed the possibility of utilization of a residue from the soybean protein concentrate present in residual alcoholic micelle of the process.
Influência da adição de BaTiO3 nas propriedades estruturais, elétricas e anelásticas de cerâmicas piezoelétricas de Bi0,5Na0,5TiO3-BaTiO3
(Universidade Federal de São Carlos, 2014-08-07) Diaz, Julio Cesar Camilo Albornoz; Silva Junior, Paulo Sergio da; https://lattes.cnpq.br/7418621942217628; https://lattes.cnpq.br/5796421075622433
Motivated by the great growth presented in the last decade in research on lead-free piezoelectric ceramics and the fact that some ceramic systems, as those based on bismuth, have been identified as promising candidates to substitute the lead zirconate titanate (PZT) in their present technological applications, was proposed as the objective of this work, study the effect of adding 𝐵𝑎𝑇 𝑖𝑂3 (BT) on the structural, electrical and anelastic properties exhibit by the system (1−𝑥)𝐵𝑖0.5𝑁𝑎0.5𝑇𝑖𝑂3−𝑥𝐵𝑎𝑇 𝑖𝑂3 (BNT-BT). The structural characterization was performed by the techniques of X-ray diffraction (XRD) and Raman spectroscopy. The morphological and compositional aspects (qualitative), in the calcined powders, and the sintered samples were studied by scanning electron microscopy (SEM). The ferroelectric and dielectric character of the compositions were obtained through characterization of ferroelectric hysteresis exhibit and using the technique of electrical impedance spectroscopy, respectively. Phase transitions and the possible mechanisms of anelastic relaxation were studied by the technique of mechanical spectroscopy. Samples were obtained by the method of solid state reaction, where it was possible to obtain compositions with 0.00 ≤ 𝑥 ≤ 0.08 with relative density greater than 95% and without the presence of spurious or secondary phases. On profiles of X-ray diffraction for the different studied sintered compositions was applied the method of Rietvelt refinement which allow the determination and confirmation of the crystal structures in the samples under study, and the presence of a morphotropic phase boundary (MPB) for the BNT-BT. The XRD results were corroborated by the results of Raman spectroscopy. The ferroelectric nature of the different compositions of BNT-BT system studied was confirmed. Electrical phase transitions (F-Af and Af-P) and structural transitions (R-T and T-C) exhibited by the BNT-BT were characterized by mechanical spectroscopy (using a dynamical mechanical analyzer (DMA)), and by electrical impedance spectroscopy, employing the results in complementing the electrical and structural phase diagram of this system. In addition to the phase transitions obtained, the technique of mechanical spectroscopy for compositions between 0.00 ≤ 𝑥 ≤ 0.03, allowed the observation of a complex process of anelastic relaxation that was associated with interactions and mobility of different defects present, which possibly contribute significantly to an increase of conductivity in these materials, which had not been previously reported in the literature.
Otimização do processo de soldagem por fricção por ponto (FSpW) de soldas de materiais similares e dissimilares de ligas leves
(Universidade Federal de São Carlos, 2014-08-07) Piccolo, Debora Regina Gastaldi; Alcântara, Nelson Guedes de; https://lattes.cnpq.br/3123107570992184; https://lattes.cnpq.br/3586398504200450
Currently there is a lot of pressure in the aeronautical and automobilistic transport section in order to reduce the fuel consumption and consequently cost and gas emissions. This measure has increased in the last years the use of light alloys, as the alluminium s alloys and of more efficient methods for joining them. Nevertheless, there is some difficult in joining these alloys using the conventional methods. The Friction Spot Welding (FSpW) is a solid state joining technique, that has great advantages regarding others joining techniques, and therefore could be a viable alternative to replace the established technologies as Resistance Spot Welding (RSW) and riveting, which are widely used by the automotive industry. The present works aims to study, through the Friction Spot Welding process (FSpW), the similar welding conditions of AA5754-H111 aluminium alloy and also the dissimilar welds between AA5754-H111 aluminium alloy and AZ31-O magnesium alloy. The influence of process parameters over the microstructure and the mechanical properties of the welded joints, as well as, the optimization of the welding process were evaluated. The joints were produced in overlap configuration through a different combination of parameters, which were established by statistical methods for design of experiments, and later submitted to mechanical and metallurgical characterization. The results proved the feasibility of joining the similar and dissimilar plates of aluminium AA5754 and magnesium AZ31 through FSpW process. The similar joints showed great results of shear strength. However, in the dissimilar joints, the utilization of a zinc interlayer, in spite of leading to a great superficial finishing, didn t effectively decrease the amount of intermetallic compounds formed in the joint as it was expected, leading to low values of shear strength.
Reações de adição conjugada de indóis e oxindóis empregando organocatálise
(Universidade Federal de São Carlos, 2014-08-07) Silva, Rodrigo César da; Paixão, Márcio Weber; https://lattes.cnpq.br/3773908504964104; https://lattes.cnpq.br/3123398279809365
Organocatalysis has emerged as a powerful synthetic tool which accelerated the development of new methods to obtain symmetric and asymmetric molecules. Furthermore, the use of small organic molecules such as amino acids derivatives, ureas, thioureas and squaramides are the leading characters in this area. In the present work, we designed a new class of organocatalysts, acting as hydrogen bond donors activation mode and subsequently catalytic activity was evaluated in the Michael addition type reactions of indoles to nitrostyrene. The synthetic route for obtaining the organocatalysts was extremely short, providing the product in just a single synthetic step in excellent yields. (CONTINUA...)
Regulamentar para quê(m)? As representações sociais de prostitutas sobre a regulamentação da "profissão"
(Universidade Federal de São Carlos, 2014-08-07) Afonso, Mariana Luciano; Scopinho, Rosemeire Aparecida; https://lattes.cnpq.br/4770451465556845; https://lattes.cnpq.br/4148954960536963
The general theme of this research is prostitution, known by common sense as the "oldest profession in the world", and always surrounded by much controversy, both nationally and internationally. Historically, the states are divided between their prohibition or regulation. Some social groups claim that prostitution should be regulated and recognized as a "job like any other," while others consider its exercise as a form of exploitation and commodification of the female body and expression of unequal power relations between men and women. Nationally, prostitution is already included in the Brazilian Code of Occupations, indexed with number 5198-05 in the category of "service provider". The Brazilian Penal Code does not criminalize the prostitutes, but punishes pimping. Since 1997 four law projects were shown to regulate prostitution, after many discussions, however, did not come to a conclusion about them, which seems to reflect the divergences in society about the subject. In 2012, Jean Wyllys proposed PL 4211/2012 which is currently in progress. In this interim, we propose to investigate what the main affected, the prostitutes themselves, think about the question. The theoretical and methodological framework is the Theory of Social Representations. The empirical field where this research was conducted is the central area of Sorocaba (SP), the region is historically known for sheltering prostitution. The subjects of this research are seven low-income prostitutes that exert their activity on the streets of this area. To understand the social representations of the subjects, direct observations were made and registered in a field diary and in-depth interviews, with semi-structured script were conducted. Institutions of the city with close contact with these women have been mapped: One of the Security Councils of Sorocaba, composed by tradespeople and police, one religious association, that is wing of the Catholic Church, and one Non- Governmental Organization (NGO), which works with Damage Reduction policy. Interviews with representatives of these institutions were conducted and documents produced by them were analyzed. To further understand the national context in which the theme is located, the content of the law projects, and the forces against and in favor of regulation were investigated, especially between State, Church, and social movements. It s concluded that the social representations of prostitutes are far from these speeches, and it s anchored in their own experience. They didn t know the particularities of each one of the law projects and they are against the regulation of prostitution.
Análise de um método de elementos finitos com interface estabilizada para a equação de advecção - reação
(Universidade Federal de São Carlos, 2014-08-07) Leiva, Rosalia Taboada; Rodrigues, Savio Brochini; https://lattes.cnpq.br/1302085627916721; https://lattes.cnpq.br/4849264231932809
In this study we present an interface stabilised finite element method for the scalar advection-reaction equation... (CONTINUA - VER NO PDF)
Polímeros de hidrogéis com água de reúso e de abastecimento no desenvolvimento de mudas de espécies arbóreas da floresta estacional semidecidual
(Universidade Federal de São Carlos, 2014-08-07) Ferreira, Alexandre José Domingues; Penha, Alessandra dos Santos; https://lattes.cnpq.br/9799774247477252; https://lattes.cnpq.br/6154403932271449
The seasonal semideciduous forests from southeastern Brazil have high plant species richness, but have been strongly affected by human interferences, which let them very degraded: nowadays they are represented by small isolated fragments, immersed in a landscape dominated by agriculture and large urban centers. In this sense, the ecology of restoration arises in order to facilitate, accelerate and direct the processes of secondary succession to manage such areas, considering the knowledge about theoretical concepts that aim to review the effectiveness of natural ecosystem management techniques and practices. In such a perspective, we aimed in this experiment to test the following question: During de production of seedlings of the native forest tree species, Ceiba speciosa (Malvaceae) and Handroanthus heptaphyllus (Bignoniaceae), different dilutions of hydrogel associated to irrigation with reused water, could improve their development? To answer this question, we selected three treatments (1g, 4g and 8g of hydrogel), beyond the witness (no hydrogel). The seedlings of both species were irrigated during one month with water reused and water supply. After this period, we estimated the growth of seedlings: roots, height and diameter. We used ANOVA (p = 0.001), and Tukey s test to verify significative differences between the mean of the treatments. We found significative differences in both height and diameter growth from 4g of hydrogel as to C. speciosa as H. heptaphyllus. In relation to the growth of root system of both tree species, the mean of superficial root area differed significantly from 4g of hydrogel when compared to the witness, confirming our initial assumption that the roots would grow in a lower proportion of area because they are in their hydric comfort zone. With such results added to theoretical knowledge in the ecology of restoration, the association of hydrogels with reused water comes to stand up for the sustainable use of water in the irrigation of native seedlings.