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Oil–water two-phase flow experiments were conducted in horizontal ducts made of Plexiglas® to determine the in situ oil fraction (holdup) by means of the closing valves technique, using mineral oil (viscosity: 0.838 Pa s at 20 °C; density: 890 kg m−3) and tap water. The ducts present sudden contractions from 50 mm to 40 mm i.d. and from 50 mm to 30 mm i.d., with contraction ratios of 0.64 and 0.36, respectively. About 200–320 tests were performed by varying the flow rates of the phases. Flow patterns were investigated for both the up- and downstream pipe in order to assess whether relevant variations of the flow patterns across the sudden contraction take place. Data were then compared with predictions of a specific correlation for oil–water flow and some correlations for gas–water flow. A drift-flux model was also applied to determine the distribution parameter.

Underground gas storage (UGS) and CO 2 sequestration (CCS) are strategic practices to address the growing demand of energy and reduction of greenhouse gas emission. There is an interest from the energetic, economic, and environmental viewpoint to store as much gas as possible consistent with the requirement of a safe disposal. A transversely isotropic geomechanical model is developed and calibrated using the vertical and horizontal displacements measured by SAR-based interferometry over an exhausted gas field located in Northern Italy where UGS is active since 1986. The predictions show that a maximum storage pressure up to 140% p i , p i being the virgin fluid pore pressure, may yield a 400% increase of the gas stored relative to p i provided that an accurate assessment of the parameters defining the yield surface, i.e. friction angle and cohesion in the Mohr–Coulomb criterion, is performed for the reservoir formation. No appreciable risk for the integrity of the sealing layer is ever expected, along with a negligible impact on the ground structures. Land motion does not exceed few centimeters with the differential displacements safely below the bound required by structural safety.

HLA phenotypes of 64 Italian pediatric patients with celiac disease (CD) were compared with those of a group of healthy controls. DR3 and DR7 are significantly increased as reported in other populations. In addition an increase of heterozygotes DR5/DR7 was observed in our patients. The Hardy-Weinberg distribution in the patients group shows a disequilibrium due to the genotype DR5/DR7. Our data confirm that more than one HLA gene product is associated with CD: one with DR3 and the other with DR7.