Point-Contact Spectroscopy in MgB_2: from Fundamental Physics to Thin-Film Characterization

In this paper we highlight the advantages of using point-contact spectroscopy (PCS) in multigap superconductors like MgB_2, both as a fundamental research tool and as a non-destructive diagnostic technique for the optimization of thin-film characteristics. We first present some results of crucial fundamental interest obtained by directional PCS in MgB_2 single crystals, for example the temperature dependence of the gaps and of the critical fields and the effect of a magnetic field on the gap amplitudes. Then, we show how PCS can provide useful information about the surface properties of MgB_2 thin films (e.g. Tc, gap amplitude(s), clean or dirty-limit conditions) in view of their optimization for the fabrication of tunnel and Josephson junctions for applications in superconducting electronics.Comment: 11 pages, 7 figures; Proceedings of 6th EUCAS Conference (14-18 September 2003, Sorrento - Italy

Assessing activity-related vehicle emissions through an integrated activity-based modelling framework

Policymakers are increasingly recognizing the importance of source-related measures, instead of technological actions, to tackle the problem of traffic air pollution. Unfortunately, traditional trip-based models fail to make accurate predictions for activityrelated policy questions. Due to the richer set of concepts which are involved in activitybased transportation models, the use of these models should be encouraged to contribute to this part. In this research the activity-based model ALBATROSS was used to assess trips and emissions produced by passenger cars in the Netherlands. The results were segregated according to trip motive to gain more insights into the contribution of different trips towards the total amount kilometres and air pollution. The predicted values correspond well with the reported values from the Dutch Scientific Statistical Agency. Predictions for total travelled distance, carbon dioxide, carbon monoxide, nitrogen oxide, sulphur dioxide and particulate matter (PM) differed not more than 8% from the officially reported values. Concerning the classification into trip motive, the commuter trips produced almost half of the PM emissions. Further, trips with a social purpose caused 17% of the PM emissions, and shopping and leisure trips each accounted for 10% of the total PM emissions. This paper is novel in the sense that it reports on the applied methodology and presents the practical results from a case study of the activity-based modelling approach as well