Visualization of local ethylene polymerization activity on a flat CrOx/SiO2/Si(100) model catalyst

Flat model catalysts give access to fundamental aspects of olefin polymerization over heterogeneous catalysts. They are especially suited for the investigation on the early stages of polymer film growth employing scanning probe and electron microscopy. The polymerization centers are confined to a well defined two dimensional plane that remains constant during the polymerization. Using the Phillips (CrO x /SiO2) catalyst as an example we demonstrate how this approach can be used do visualize the lateral distribution of polymerization activity in the initial stages of polymer growt

Which synthesis?: strategies of theoretical integration and the neorealist-neoliberal debate

Despite growing interest in the promises and problems of theoretical synthesis among political scientists, frameworks for assessing the potential advantages of different pathways to theoretical integration are scarce. We build on the conceptualization of alternative strategies for synthesis proposed by Jupille, Caporaso, and Checkel and assess the implications of two criteria — parsimony and empirical fit — for understanding the relationship between two influential strands of international relations theory, neorealism and neoliberalism. Neorealists present concerns about relative gains as evidence of the limited scope of the neoliberal theory of international cooperation. We argue that, on the contrary, neoliberalism provides theoretical tools that are indispensable to determine when and why relative-gains concerns thwart international cooperation, and that this provides a strong case for subsuming neorealism under neoliberalism in a parsimonious synthesis. We apply this framework to explain an empirical puzzle: why two arch-rival states — Austria and Prussia in the second half of the 18th century — succeeded in cooperating in some cases but failed in others