A Service Station Location Model to Explore Prospects and Policies for Alternative Transport Fuels: A Case of CNG Distribution in Italy

CNG is an example of alternative gaseous fuel whose market development requires supply infrastructure (pipelines), refuelling stations and alternative vehicles to exist at the same time, which is known as the \u2018\u2018chicken and egg dilemma\u2019\u2019. In this chapter, a case study of limited or locally nonexistent market development for CNG in an Italian frontier region is analyzed and a mixed integer non linear programming model is introduced to evaluate the effect of incentive measures envisaged by the regional government to foster refuelling station development. It is found that, taking an entrepreneurs\u2019 perspective of maximizing profits, even with substantial capital grants investors are more likely to choose higher demand areas, in spite of fiercer competition, rather than areas without stations. Subsidies should be more specifically targeted to critical areas to be efficient

On the ergodic theory of impulsive semiflows

We consider impulsive semiflows and establish sufficient conditions to the existence of invariant measures. Namely, the impulsive set and its image are both submanifolds of codimension one that are transversal to the flow direction. Moreover, we show that under the same conditions a Variational Principle holds

Effects of technetium on marine micro-organisms

Eleven bacterial species have been isolated from the upper layer of intertidal sediments collected along the Belgian coast (Coxyde). Three of them (no. 1, 4 and 11) have been chosen for their halophilous character. One species has been identified as Flavobacterium halmephilum, the other two are being investigated. Effects of technetium (99Tc) have been studied on a mixed bacterial population isolated from sediments, as well as on the three halophilic species.At the concentrations utilized in this work (up to 100 microg ml-1), 99Tc has no evident effects on bacterial growth. Uptake of technetium (99Tc and/or 95mTc) has been investigated in the mixed bacterial population, in the three halophilic bacteria (including Flavobacterium halmephilum) and in the benthic ciliate Uronema marinum. It has been found that technetium is taken up by all these micro-organisms. However, the transfer factor (TF) in bacteria may vary considerably (from 0.5 to 200), but the cause of this variability is not known and deserves further study.The ciliate Uronema marinum, which feeds on living marine bacteria, was found to take up 95mTc added to the culture medium. However, the TF in this ciliate is rather low (from 1.4 to 5.5). Because it feeds on bacteria, Uronema marinum is supposed to take up technetium from water (direct contamination) as well as from contaminated bacteria (indirect contamination). Experiments with 95mTc-labeled bacterial cells might be useful, as they could indicate which form of contamination (direct or indirect) is prevailing