Aula creativa para la enseñanza de la matemática en la universidad

En este trabajo se describe una serie de actividades y acciones llevadas a cabo en el marco de una propuesta didáctica basada en el enfoque de la formación por competencias. Se tuvo en cuenta lo inesperado como disparador de respuestas creativas por parte de los alumnos y el cambio de los esquemas de la clase tradicional, tanto en el espacio físico como en los roles de docentes y alumnos. Se muestran también las respuestas de los alumnos a las actividades señaladas y las opiniones de los mismos ante la propuesta. Finalmente se expresan conclusiones y reflexiones elaboradas por el grupo de docentes que participó de las experiencias.This work describes a series of activities and actions carried out within the framework of a didactic proposal based on the competency-based training approach. The unexpected was taken into account as a trigger for creative responses by the students and the change in the schemes of the traditional class, both in the physical space and in the roles of teachers and students. The students’ responses to the indicated activities and their opinions regarding the proposal are also shown. Finally, conclusions and reflections elaborated by the group of teachers who participated in the experiences are expressed.Fil: Cívico, Alejandra Edith. Universidad Nacional de Cuyo. Facultad de Ciencias EconómicasFil: Berliansky, Ana. Universidad Nacional de Cuyo. Facultad de Ciencias EconómicasFil: Demunno, Cecilia Yasmín. Universidad Nacional de Cuyo. Facultad de Ciencias EconómicasFil: Mancinelli, Carolina Cecilia. Universidad Nacional de Cuyo. Facultad de Ciencias EconómicasFil: Todaro, Alejandra. Universidad Nacional de Cuyo. Facultad de Ciencias Económica

Geometrical isomers of [TEAH][Co(L-Se)(2)]center dot xH(2)O: synthesis, structural, spectroscopic and computational studies

Trans-1, [HNEt3][Co-III(L-Se)(2)]center dot H2O and cis-1, [HNEt3][Co-III(L-Se)(2)]center dot 3H(2)O have been synthesized and characterized by single-crystal X-ray studies. The counter ion Et3NH+ plays a crucial role in the crystal packing leading to the formation of two distinctly different supramolecular assemblies in the two complexes. In trans-1, Co-bisphenolate units and triethylamine molecules are arranged in a linear fashion leading to a supramolecular columnar assembly along the crystallographic a-axis. In this assembly, triethylammonium ions are sandwiched between successive Co-bisphenolate units and act as gluing agents joining Co-bisphenolate units on either side through C-H center dot center dot center dot pi interactions. In sharp contrast to trans-1, Co-bisphenolate units and triethylammonium ions in cis-1 are arranged in a helical supramolecular assembly through similar C-H center dot center dot center dot pi interactions along the crystallographic b-axis. The Se center dot center dot center dot Se van der Waals interactions may be responsible for the predominant occurrence of the cis-isomer. The cyclic voltammetric studies showed quasi-reversible waves for the cobalt(III) -> cobalt(II) reductions with E-1/2 = 0.635 and 0.628 V vs. Ag/AgCl for cis-1 (at similar to 5 degrees C) and trans-1 (at similar to 25 degrees C), respectively. DFT calculations show that the trans-form is the thermodynamic product with higher stability than the cis-one, which is consistent with the variable temperature H-1 NMR studie