Um Estudo de caso preliminar: a evasão no Bacharelado em Química do Instituto de Química de São Carlos

Aquest treball presenta un estudi de casos destinat a la recopilació d'informació qualitativa i quantitativa sobre l'abandonament dels estudis del camp de la química de l'Institut de Química de São Carlos. Recentment, s'han estat avaluant els possibles factors que contribueixen a l'abandonament dels estudis mitjançant contactes amb els antics alumnes. Els motius més esmentats com a responsables de l'abandonament, en ordre decreixent, van ser: falta de vocació, l'adaptació a la ciutat de São Carlos, l'adaptació al curs i/o dificultats acadèmiques i el nivell socioeconòmic.This paper presents a case study aiming at gathering qualitative and quantitative information about the evasion from the chemistry course of Institute of Chemistry of São Carlos. Recently, it has been also assessing the probable contributing factors to evasion, by contacting with the former students. The reasons most frequently reported as being responsible for the evasion, in descending order, were: lack of vocation, adaptation to the city of São Carlos, adaptation to the course and/or academic difficulties, and socioeconomic status

O método da pesquisa-ação para analisar o uso de recursos humorísticos no ensino de química: resultados preliminares

Este trabalho apresenta análises iniciais de estudo da estratégia de utilizar recursos humorísticos (charges, músicas, anedotas) no ensino de química em uma turma de primeiro ano do Ensino Médio. Os resultados indicam que os alunos veem a disciplina como interessante porém a julgam com estereótipos tradicionalistas. Mas com o uso dos recursos esta tornou-se mais atraente e contextualizada, quando utilizados de forma correta. E ainda, ressalta-se a importância da estratégia da pesquisa-ação no estudo, para aproximar a pesquisa aos reais problemas da sala de aula

Um Estudo de caso preliminar: a evasão no Bacharelado em Química do Instituto de Química de São Carlos

This paper presents a case study aiming at gathering qualitative and quantitative information about the evasion from the chemistry course of Institute of Chemistry of São Carlos. Recently, it has been also assessing the probable contributing factors to evasion, by contacting with the former students. The reasons most frequently reported as being responsible for the evasion, in descending order, were: lack of vocation, adaptation to the city of São Carlos, adaptation to the course and/or academic difficulties, and socioeconomic status.Aquest treball presenta un estudi de casos destinat a la recopilació d'informació qualitativa i quantitativa sobre l'abandonament dels estudis del camp de la química de l'Institut de Química de São Carlos. Recentment, s'han estat avaluant els possibles factors que contribueixen a l'abandonament dels estudis mitjançant contactes amb els antics alumnes. Els motius més esmentats com a responsables de l'abandonament, en ordre decreixent, van ser: falta de vocació, l'adaptació a la ciutat de São Carlos, l'adaptació al curs i/o dificultats acadèmiques i el nivell socioeconòmic

Towards to the trans-bromination of 2-styrylpyridine with a palladacycle intermediary and structure analysis for trans-1,2-dibromo-2-styrylpyridine

The simple halogenation of alkynes in conventional organic reactions gives a blend of cis and trans isomers. It is proposed then, a synthesis of stereospecific halogenation of alkynes in trans position, using palladacycle as intermediaries. The recrystallization of the compound obtained by bromination of 2-Styrylpyridine, with cyclepalladium intermediary results in a single crystal, which is subjected to X-ray diffraction. The crystal packing is established through weak interactions of three types. The first one is of the type pi x pi interactions, from symmetry operation, between the centroids. The second one is of the type C-X center dot center dot center dot pi interactions. And the last type is an anomalous intermolecular interaction between halogens, C-X center dot center dot center dot X-C, with bond distances smaller than the sum of the van der Waals radii. The conformation on the C=C bond is trans and the dihedral angle between the aromatic rings is (with esd approximate) 18.1(3)degrees. (C) 2010 Elsevier B.V. All rights reserved

A three-dimensional network constructed from the assembly of 1,3-diaminopropane-copper(II) and tetracyanopalladate(II) moieties

The coordination polymer [Cu(Pd(CN)(4))(pn)](n) (pn = 1,3-diaminopropane) has been synthesized and characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. The crystal structure showed that three cyano groups of each [Pd(CN)(4)] unit bridge Cu(II) centers leading to the formation of a three-dimensional network. A series of bifurcated hydrogen bonds between the amino groups of the diamine and the nonbridging cyano groups of the cyanometallate result in the organization of suprarnolecular chains and rings along the polymer. (c) 2008 Elsevier B.V. All rights reserved

Stereoselective sodium borohydride reductions of cyclopentanones: influence of ceric chloride on the stereochemistry of reaction

In this paper we describe the reduction by NaBH4 of some cyclopentanones containing an oxygenated function at the side chain position beta to the carbonyl group, both in the presence and in the absence of CeCl3. Some suggestions for the rationalization of the results are discussed, considering the stereochemical course of the reactions