Authors:F. Fraga, V. Soto, E. Rodríguez-Núñez, J. Martínez-Ageitos and V. Rodríguez
The study of the cure reaction of the epoxy
network diglycidyl ether of bisphenol A with amantidine is a useful tool to
characterize the industrial behaviour of this material. The total enthalpy
of reaction, the glass transition temperature and the partial enthalpies at
different cured temperatures have been determined using differential scanning
calorimetry in dynamic and isothermal mode. Two models, one based on chemical
kinetics and the other accounting for diffusion were used and compared with
experimental data. It can be seen that the inclusion of a diffusion factor
in the kinetic model is negligible.
Authors:F. Fraga, V. Soto, J. Blanco-Méndez, A. Luzardo-Alvarez, E. Rodríguez-Núñez, J. Martínez-Ageitos and M. Pérez
Knowledge of the the kinetic study of chitosan/genipin
allow to know the different effects that time and temperature have on the
cure reaction of the material.
The total enthalpy of reaction,
the glass transition temperature and the partial enthalpies have been determined
using DSC in dynamic mode. Two models, one based on chemical kinetics and
the other accounting for diffusion were used. The incorporation of the diffusion
factor in the second model allowed for the cure kinetics to be predicted the
whole range of conversion.
Authors:A. Gelen, N. López, O. D. Maslov, A. G. Belov, M. V. Gustova, O. Díaz, J. Beltrán, J. Soto, M. V. Manso Guevara, M. Pérez and M. J. Simón
Twenty six elements was studied preliminary in the superficial sediments of Havana Bay using gamma activation analysis by
the electron accelerator microtron MT-25 at the Flerov Laboratory of Nuclear Reactions, JINR. Samples from five zones of Havana
Bay including the three coves were analyzed. The obtained results show a close relation between the concentration levels of
the studied elements and the pollution sources. Some elements (As, Ba, Ni, Pb, Cu, Zn, Fe, Cr, Mn) have high concentration
levels compared to the values for other environmental marine sediments reported in the literature.