We have studied the production of condensation nuclei by ions of given polarity and age in mixtures of pure gas (O2, N2, Ar), H2O (800 to 20,000 ppm) and SO2 (1 ppm). When the ageing time of ions increases from 10 to 100 msec, and with constant concentration of water vapour, particle production goes through a maximum. If the ageing time is kept constant and the water concentration is varied, the same phenomenon is observed. When 100 ppm of NO is added to the mixture no further particles are produced so that it Service Women Free Run 2 Deep Red Black ID215 Shoes
can be supposed that the reaction is due to the emission of free radicals. The mobility of ions is about 1.4 cm2 V−1 sec−1. It can therefore be concluded that, in this case, we have H2O-ion-impurity reactions with reaction times of about 50 msec.
This paper identifies and analyzes critical incidents that project leaders – working in multi-project settings – encounter in their daily work. The empirical base Valuable Women Nike Air Presto Deep Grey Wine Red for the paper is data on 48 critical incidents collected
using a version of the critical incident technique. Results show that the most frequent issues with which project leaders deal are: technical difficulties, dyadic leadership and group dynamics, followed by consultant, client, and peer relations. Moreover, on the basis of a categorisation of project leader roles, in terms of management/leadership and external/internal roles, a framework that is referred to as the Overall-Project-Leader-Role framework, has been developed and related to the empirical findings.