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The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data- taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1+/-0.9 ��m and a relative momentum resolution ��p/p = (4.83+/-0.16) \times 10-4 GeV-1 \times pT have been measured for high momentum tracks. 34 pages, 25 figures

Abstract This paper investigates the impact of the oxidizing agent used in the physical activation of pyrolysis chars on activated carbons (AC), and their efficiency in tar cracking. The materials are produced from buckwheat husk, which is a French local biomass. Slow pyrolysis was chosen to favor the production of raw chars. Activated chars were then prepared by physical activation under steam or CO2. The materials produced were physically and chemically characterized before being implemented in a fixed bed. The efficiency of materials in removing tar from syngas was studied, and ethylbenzene (EB) was chosen as the tar surrogate. The purification efficiency of the chars and AC was deduced from the EB conversion profiles in comparison with thermal cracking. The nature of the oxidizing agent impacted the porosity and mineral composition of the AC produced: CO2 activation produced ACs with more carbon and less ash content. This is because the reduction of carbon with carbon dioxide presents a kinetic between 2 and 5 times slower than that conducted in the presence of steam. CO2 activation also resulted in a higher relative microporosity (89%) than steam activation (61%), which itself gives a higher surface area. Pyrolysis char did not generate any interest for EB catalytic cracking, whereas ACs demonstrated higher performances. This is due to their higher level of porosity and higher ash content. BH–H2O, which presents higher porosity, produced a better catalytic effect and was more resistant to deactivation.

This work presents the re-engineering of the TRANSAT 1.0 code which was developed to perform off-design and transient condition analysis of Saturators and Direct Contact Heat Exchangers. This model, now available in the 2.0 release, was originally implemented in FORTRAN language, has been updated to C language, fully coded into MATLAB/Simulink® environment and validated using the extensive set of data available from the MOSAT project, carried out by the Thermochemical Power Group of the University of Genoa. The rig consists of a fully instrumented modular vertical saturator, which is controlled and monitored with a LABVIEW® computer interface. The simulation software showed fair stability in computation and in response to step variation of the main parameters driving the thermodynamic evolution of the air and water flows. Overall the model proved to be reliable and accurate for energy systems simulations.

We study the development potential of ultrasonic thermometry in a liquid fluctuating sodium environment similar to that present in a Sodium-cooled Fast Reactor, and thus investigate if and how ultrasonic thermometry could be used to monitor the sodium flow at the outlet of the reactor core. In particular we study if small temperature variations in the sodium flow of e.g. about 1% of the sodium temperature, i.e., about 5°C, can have a reliably-measurable acoustic signature. Since to our knowledge no experimental setups are available for such a study, and considering the practical difficulties of experimentation in sodium, we resort to a numerical technique for full wave propagation called the spectral-element method, which is a highly accurate finite-element method owing to the high-degree basis functions it uses. We obtain clear time-of-flight variations in the case of a small temperature difference of one percent in the case of a static temperature gradient as well as in the presence of a random fluctuation of the temperature field in the turbulent flow. The numerical simulations underline the potential of ultrasonic thermometry in such a context.