0000000000928221
AUTHOR
M. Gentile
Growth and Characterization of Anodic Films on Al-Nb Alloys
Abstract The anodizing behaviours of sputtering-deposited aluminium, niobium and Al-Nb alloys, containing 0.4, 7.5, 21, 40 and 55 at.% niobium, have been examined in 0.1 M ammonium pentaborate electrolyte with interest in the morphology, structure and electronic properties of the anodic oxides. Transmission electron microscopy revealed amorphous oxides, containing units of Nb2O5 and Al2O3, with formation ratios intermediate between those of anodic alumina and anodic niobia. Photocurrent spectroscopy provided increased understanding of the electronic properties of the anodic films, suggesting the formation of “mixed oxides” with insulating behaviours. The estimated band gap values are correl…
mCLT: an application for collaborative learning on a mobile telephone
Mobile technologies offer new opportunities for distance learning and enable people to collaborate anywhere. This paper introduces an innovative mobile platform for computer-supported collaborative learning in which traditional methodologies of collaboration have been improved, based on 3rd-generation mobile telephones. Students can collect and share live data immediately, anywhere and at any time. This enables them to play an active role in the knowledge-building process. The mCLT is potentially an application for ubiquitous collaborative learning.
Structural and compositional analysis of anodic films on Al-Nb sputter-deposited alloys
The photoelectrochemical behavior of anodic films on Al alloys, containing titanium, tantalum, and tungsten (valve metals), has been studied as a function of alloy composition and anodizing conditions. Photocurrent spectroscopy has been used to get information on bandgap and the flatband potential values of different mixed oxides. Both insulator-like and semiconducting behavior has been observed for anodic oxides grown on Al-W and Al-Ti alloys dependent on alloy initial composition. Optical bandgap values, Eg,opt, of different oxides are in accordance with predictions based on the correlation between Eg,opt and the difference of electronegativities of the oxide constituents, indicating pote…
Il disegno sperimentale
Assessment of humoral and cell-mediated immunity against Bordetella pertussis in adolescent, adult, and senior subjects in Italy
SUMMARYHumoral and cell-mediated immunity (CMI) againstB. pertussiswas assessed in a sample of adolescent, adult and senior subjects distributed in five different geographical areas in Italy. Most (99·1%) subjects had IgG anti-pertussis toxin (PT) antibodies exceeding the minimum detection level [⩾2 ELISA units (EU)/ml]. There were no significant differences between the genders; 6·2% samples recorded titres ⩾100 EU/ml. CMI was positive [stimulation index (SI) ⩾5] against PT in 39·0% of all samples. This study suggests thatB. pertussiscontinues to circulate in age groups that have been previously considered to be uninvolved in the circulation of this pathogen and that adolescent and adult pe…
BENDAMUSTINE (B) IN COMBINATION WITH RITUXIMAB (R) FOR PATIENTS WITH RELAPSED/RESISTANT CHRONIC LYMPHOCYTIC LEUKEMIA (CLL): AN ITALIAN MULTICENTRE RETROSPECTIVE STUDY
La sperimentazione didattica: il porsi del problema
Il controllo delle variabili
Infrastrutture, campagna e tessuti urbani a Partinico. Tra la SS113 e viale dei Platani
The new district connects, along the north-south direction, Partinico with the train station and, in the east-west direction, it opens on an agricultural urban park between viale dei Platani and the SS 113 road. The park and the quarter are a unified composition, characterized by the continuity of agricultural soils. The residential buildings are crossed on the ground floor by fields of gerberas and chrysanthemums and ditches that are part of the network of the pedestrian and cycle park, whose spatiality is articulated through the different texture of the cultivated species, from flowers to vegetables, from vineyards to orchards, by citrus groves and olive groves. From the agricultural urba…