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...

Introduction The possibility of using vegetable oils as fuel has been documented in the beginning of diesel engines. Biodiesel produced from waste oil by trans-esterification process can be used as a substitute for diesel in internal combustion engines [1]. Biodiesel can be produced by the transesterifcation of vegetable oils [2] such as soyabean oil, rapeseed oil, sunflower oil etc. [3]. Trans...

The problem of oscillations detection for nonlinear systems is addressed. The notion of homogeneity in bi-limit from (Andrieu, et al., 2008) is extended to local homogeneity. Next, sufficient conditions of oscillations existence for locally homogeneous systems are formulated. The proposed approach allows one to estimate the number of limit cycles and the regions of their location. Efficiency of...