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Abstract. Dust samples from rainfall residues have been collected in southeast Italy (40 • 20 N, 18 • 6 E) during dust outbreaks occurred from April to June 2002 to characterize morphological and elemental particle composition by different techniques, and investigate the dependence of particle properties on source regions. Four-day analytical back trajectories and satellite images have been used to infer source regions of the investigated dust samples.It has been found that the TOMS absorbing aerosol index was in the range 0.7-2.2 over Southern Italy when samples have been collected. The particle-size and -shape analysis by a scanning electron microscope (SEM) has revealed either that the particle-diameter distribution was between 0.3 and 30 µm with median-diameter values between 1.7-2.4 µm, and that the particles were characterized by a roundness factor varying from 0.8 to 2.5. The infrared transmission spectra have allowed recognizing that all dust samples contained a significant amount of illite. The X-ray energy dispersive (EDX) measurements have revealed that the Al/Si ratio of the transported dust varies from 0.41 to 0.50, and that the Al/Si,

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Langmuir-Blodgett films of copper(II) [tetrakis ((3,3-dimethylbutoxy)carbonyl)]phthalocyanine and copper(II) [tetrakis(n-butoxycarbonyl)]phthalocyanine have been studied as sensitive elements of gas sensors. Moreover, alternate LB films of the two compounds and LB films obtained from a 1:1 mixture of them have also been investigated. In particular, after exposure to NO 2 oxidizing gas, the electrical conductivity of the materials goes through a maximum at a temperature of about 170 °C corresponding to the maximum sensitivity to the gas. The sensitivity and stability of the response of the active layers to NO2 are discussed as well as the application of these materials as the sensitive elements for gas-sensing devices.