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A 10 MJ DES railgun with 12 current inputs distributed along the 50-mm round bore launcher has been built at ISL. The power supply consists of 200 LCR Pulse Forming Units of 50 kJ each. The 6-m-long launcher tube containing the Cu-Cr rails is made of both wound glass fiber and wound carbon fiber reinforced plastic.This paper presents the facility and the first experimental results obtained by using projectiles made of Ti or equipped with metallic fiber-brush armatures. The triggering of the 12 DES stages is synchronized with the position of the projectile detected by -dot probes located along the launcher tube. The currents delivered by the stages are measured by means of Rogowski coils surrounding the injection slots. The maximum total current reaches 2 MA resulting from the addition of the 12 current profiles of 800 kA delivered by each stage of the DES energy supply. The launcher has proved to have an overall efficiency of about 30%. Projectiles with masses ranging from 300 g to 650 g have been accelerated up to velocities of 2300 m/s. The quality of the electrical contact between rails and armature has been analyzed by electrical measurements and flash radiographs.

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High-pressure infrared spectroscopy has been used to study the interaction of N2 with supported Rh films as a function of temperature and pressure. Adsorption equilibrium constants for N2 on Rh/X (X = Ti02, A1203, SO2) at 298 K were 0.376, 0.206, and 0.193 atm-I, respectively. The heat of adsorption for N2/Rh/Ti02 extrapolated to zero coverage was -10.2 kcal/mol.A sample film of Rh/Ti02 pretreated so as to approach SMSI conditions adsorbed N2 more tenaciously, with an adsorption equilibrium constant at 298 K of 0.541 atm-I. This work demonstrates the utility of high-pressure infrared measurements in obtaining useful surface thermodynamic data.