Characterization of a Double Metal Cyanide (DMC)-Type Catalyst in the Polyoxypropylation Process: Effects of Catalyst Concentration
The alkaline catalysts commonly applied to alkoxylation are characterized by a limited spectrum of activity caused by an irreversible termination of the polyether chains. The presented results show that double metal cyanide (DMC) catalysts reduce or eliminate the aforementioned adverse rearrangement of hydroxyl groups. Moreover, DMC catalysts indicate high activity at low concentrations (ppm range), as expressed by high polymerization rates. It was demonstrated that decreased concentrations of DMC catalyst irreversibly influence its reactivity and the dispersity of the obtained products, as exemplified by the production and determination of selected polyoxypropylenediols at different concen…
Age-Related Differences in Motivation of Recreational Runners, Marathoners, and Ultra-Marathoners
Aim: This study was aimed to investigate the influence of age on the motivations of various types of runners, namely, marathoners, ultra-marathoners, and non-starters.Methods: A total of 1,537 runners including 380 women (24.7%) and 1,157 men (75.3%) took part in the diagnostic survey and completed the motivations of marathoners’ scales questionnaire (MOMS). The effect sizes were estimated.Results: The article presents several statistically significant differences in the impact of age on the motivations of runners in different categories and compares the motivations of marathon runners, ultramarathon runners, and non-starters. The results show that young non-starters decide to run for perso…