scale, followed by the subsequent process of adaptation of migrant groups into host societies, is causing significant challenges for social research. Furthermore, these population movements involve significant adjustments in the different areas of a person's life, such as the family, social, educational or work spheres (Bronfenbrenner, 1987). This process of cultural and psychological change th...

the stereospecific polymerization of conjugated dienes began in 1954 with the first catalysts obtained by combining ticl4 or ticl3 with aluminum-alkyls, i.e. the catalytic systems previously employed for ethylene and propylene polymerizations. subsequently, many other catalytic systems were obtained and examined by a combination of transition metal or lanthanide compounds with appropriate alkyl...