This article takes up the matter of contemporary threats to cities and urbanity, setting the problems cities face today against the background of the two categories of the resilient city and the city developing sustainably. The author describes and presents the evolution of the sustainable development concept as such, as well as the generational change in priorities that has taken place where the development of urbanised areas is concerned, given the way the concept has undergone a certain devaluation, in the light of its failure to achieve fulfi lment. The challenges cities face today require multi-faceted activity, in respect of increased inclusivity, robustness and resilience, and flexibility. This leaves today’s idea of the resilient city embracing old elements of the sustainable city, but also augmenting them in various ways.
The role of the addition of nitrogen to the discharge plasma of CO lasers on thermodynamic properties and composition of the laser active medium is discussed here. It is shown that nitrogen addition improves laser characteristics and changes the composition of the laser active medium. The addition of nitrogen significantly decreases CO dissociation level and concentrations of C atoms created in plasma-chemical reactions of laser discharge.