Extração de metais (K, Mg, Ba, Ca, Cr, Mn, Li, Fe) de água produzida utilizando sistema microemulsionado

The produced water is a byproduct formed due to production of petroleum and carries with it a high amount of contaminants such as oil particles in suspension, organic compounds and metals. Thus, these latter pollutants are very difficult to treat because of its high solubility in water. The objective of this work is to use and evaluate a microemulsioned system to remove metals ( K , Mg , Ba , Ca , Cr , Mn , Li , Fe ) of synthetic produced water. For the extraction of metals, it was used a pseudoternary diagram containing the following phases: synthetic produced water as the aqueous phase (AP), hexane as organic phase (OP), and a cosurfactant/surfactant ratio equal to four (C/S = 4) as the third phase, where the OCS (saponified coconut oil) was used as surfactant and n-butanol as cosurfactant. The synthetic produced water was prepared in a bench scale and the region of interest in the diagram for the removal of metals was determined by experimental design called. Ten points located in the phase Winsor II were selected in an area with a large amount of water and small amounts of reagents. The samples were analyzed in atomic absorption spectrometer, and the results were evaluated through a statistical assesment, allowing the efficiency analysis of the effects and their interactions. The results showed percentages of extraction above 90% for the metals manganese, iron, chromium, calcium, barium and magnesium, and around 45% for metals lithium and potassium. The optimal point for the simultaneous removal of metals was calculated using statistical artifact multiple response function (MR). This calculation showed that the point of greatest extraction of metals occurs was the J point, with the composition [72% AP, 9% OP, 19% C/S], obtaining a global extraction percentage about 80%. Considering the aspects analyzed, the microemulsioned system has shown itself to be an effective alternative in the extraction of metals on synthetic produced water remediation

Já li muita coisa, então, eu posso inventar mais! A leitura literária e o desenvolvimento do pensamento criativo na infância

This study investigates the contributions of reading literature for the development of creative thinking in childhood. Its relevance consists in exploring practices that contemplate the creative thinking development in apprentices at school space and understanding the literature like a significant way to promote the creative thinking. The study is connected to the qualitaty strand. The exploratory observation and the intervention were adopted as research techniques. The field diary and the audio and video recording of the reading sections were adopted as methodological instruments. The research was conducted in the application s college from the Federal University of Rio Grande do Norte, in a 1th grade class, with 18 students between 6 and 7 years old. During the intervention, 8 readind class happened, with varied strategies and literary genres. The reading sessions were conducted through the principles of scaffolding, defended by Graves and Graves (1995). The corpus is made of speaks episodes, whose encoding semantics allowed the grouping into two central categories: divergent thinking and coauthoring of literary reader. It was taken as a theoretical framework the studies of Amarilha (2011; 2006; 2001; 1991; 1993; 1994), Alencar (2001), Coelho (2000; 1997), Culler (1999), De Masi (2005), Gallo (2000), Guilford (1977), Iser (1996), Jouve (2002), Kneller (1978), Martínez (1997), Smith (2003), Stierle (1979), Vigotski (2009; 1998), Wechsler; Nakano (2003; 2002). The analysis points to the formation of creative individuals in the classroom, through the reading of literature. Reposition the literary education front of the new social demands. Resizes the function of school in children s development, considering the children s skill in exploring, testing hypotheses and making use of their creative thinking, in climate of freedom mental. It signals, in this way, the teacher like a mediator, promoting a favorable to the development of creative thinking environment, a stimulating atmosphere, which enhances the expression of creative thinking in community

Polaritons de exciton em super-redes semicondutoras

In this work we study the spectrum (bulk and surface modes) of exciton-polaritons in infinite and semi-infinite binary superlattices (such as, ···ABABA···), where the semiconductor medium (A), whose dielectric function depends on the frequency and the wavevector, alternating with a standard dielectric medium B. Here the medium A will be modeled by a nitride III-V semiconductor whose main characteristic is a wide-direct energy gap Eg. In particular, we consider the numerical values of gallium nitride (GaN) with a crystal structure wurtzite type. The transfer-matrix formalism is used to find the exciton-polariton dispersion relation. The results are obtained for both s (TE mode: transverse electric) and p (TM mode: transverse magnetic) polarizations, using three diferent kind of additional boundary conditions (ABC1, 2 e 3) besides the standard Maxwell's boundary conditions. Moreover, we investigate the behavior of the exciton-polariton modes for diferent ratios of the thickness of the two alternating materials forming the superlattice. The spectrums shows a confinement of the exciton-polariton modes due to the geometry of the superlattice. The method of Attenuated Total Reflection (ATR) and Raman scattering are the most adequate for probing this excitations