Ana Cristina Trindade Cursino

O desenvolvimento de estratégias de aprendizagem associado à aprendizagem autorregulada contribui de forma direta para o desempenho acadêmico dos discentes. Este trabalho apresenta os resultados obtidos na avaliação de estratégias de aprendizagem de ingressantes de engenharias. Em todos os constructos avaliados foram obtidos escores médios. O maior escore foi para Ensaio/Memorização. Com isso, espera-se que ao longo do percurso formativo competências autorregulatórias sejam desenvolvidas.

Diante das dificuldades de compreensão do conteúdo de concentração das soluções, com o intuito de auxiliar no processo de ensino aprendizagem, tem-se como objetivo a elaboração, implementação e avaliação de uma sequência didática (SD) com o tema: Poluição das Águas. A sequência didática foi aplicada com 39 alunos de uma turma do segundo ano do ensino médio de uma escola pública do interior do Paraná. A SD compreendeu 8 aulas divididas em seis etapas. Os alunos responderam a questionários no decorrer das aulas e a partir das análises dos mesmos emergiram três focos, a saber: conceito de soluções, perspectiva ambiental e conceito de concentração. Com base nos resultados inferimos que a SD tem potencialidade de contribuir para a compreensão dos educandos sobre os aspectos discutidos.

Complex of 4,4’-diamino-2,2’-stilbenedisulfonic acid (DSD) with trivalent lanthanide ions Eu3+ and Tb3+ were prepared at the ratio of 3:1 (DSD:Ln). The complexes with ions present in the form of powder show black (Eu3+) and brown (Tb3+) colors. The complexometric titration and CHN elemental analysis suggest that these complexes have the general formula Eu(C14H12N2SO3SO3H)3∙3H2O and Tb(C14H12N2SO3SO3H)2(CF3SO3)∙3H2O. The shift of the 330 nm band for DSD to a longer wavelength in the infrared spectra of the complexes and the disappearance of the bands at 2921 and 2623 cm-1 are indicative of the formation of complexes with ions Eu3+ and Tb3+. Thermal analysis shows that DSD is thermally stable up to 573 K and the decomposition process of the complexes shows two and three mass losses for ions Eu3+ and Tb3+, respectively. The analysis of luminescence indicates that the complexes do not present the emission from the lanthanide moiety in the visible region. This may be related to the ligand triplet states, which are probably at lower energy than the emission state of the Eu3+ (5D0) and Tb3+ (5D4) ions.

Anais do SimPROFQUI e Workshop do PROFQUI UFAL (978-85-5722-434-6) - Concepção E Criação Do Jogo Didático: Hive O Esquadrão Químico.

A layered hydroxide salt (LHS) was used as an inorganic matrix to obtain multifunctional food compounds. The aim is to obtain higher thermal stability for vitamin anions and a slow release of aroma. Thus, vitamin B3 (nicotinate), vitamin B5 (phantothenate) and vitamin L (2-aminobenzoate) anions were intercalated by co-precipitation method. The results show an increase in thermal stability of intercalated vitamin anion since decomposition of pure vitamin B3 starts at 120 °C and after intercalation, the HSL-B3 decomposition starts at 313 °C. The intercalation products were than reacted with vanillin (3-methoxy-4-hydroxybenzaldehyde). A kinetic study showed that the release of vanillin from its nanohybrid was found to occur in a controlled manner, evidencing that the synthesized compounds can be used in formulations for the sustained release of aromas. Results showed that the intercalated anions and adsolubilized vanillin were not only less volatile since it causes the aroma to remain in the LHS for a longer period of time resulting in slow release but also have higher thermal stability when they are confined between layers. In summary, the multifunctional food supplements obtained seems to have nutraceutical, olfactory and better thermal resistance properties being suitable for potential applications in the food industry.

Continuous efforts are being made in some countries for the recovery of crude glycerin (RG/CG) and castor oil cake (COC), the two byproducts of biodiesel production. These are expected to help, not only in addressing environmental safety, but also in adding value to those byproducts, which otherwise may go to waste. Finding ways to utilize those byproducts underlines the main objective of this study. This paper presents the evaluation of (i) COC, glycerin and banana and sugarcane fibers for moisture content; (ii) COC for structural and thermal properties; and (iii) CG for its chemical characteristics. The possibility of using COC and CG with the selected fibers as reinforcement in the development of bio-composites is attempted through thermo-molding. Results revealed enhanced mechanical properties for these composites. The obtained results are discussed in terms of the observed morphology.