Test beam performance of a CBC3-based mini-module for the Phase-2 CMS Outer Tracker before and after neutron irradiation

The Large Hadron Collider (LHC) at CERN will undergo major upgrades to increase the instantaneous luminosity up to 5–7.5×10$^{34}$ cm$^{-2}$s$^{-1}$. This High Luminosity upgrade of the LHC (HL-LHC) will deliver a total of 3000–4000 fb-1 of proton-proton collisions at a center-of-mass energy of 13–14 TeV. To cope with these challenging environmental conditions, the strip tracker of the CMS experiment will be upgraded using modules with two closely-spaced silicon sensors to provide information to include tracking in the Level-1 trigger selection. This paper describes the performance, in a test beam experiment, of the first prototype module based on the final version of the CMS Binary Chip front-end ASIC before and after the module was irradiated with neutrons. Results demonstrate that the prototype module satisfies the requirements, providing efficient tracking information, after being irradiated with a total fluence comparable to the one expected through the lifetime of the experiment

The dynamics of water in nanoporous silica studied by dielectric spectroscopy

International audienceBroad-band dielectric spectroscopy is used to investigate the dynamics of hydration water on the surface of the cylindrical pores of a nanostructured silica material (MCM-41, with pore diameter of 3.2 nm) at various hydrations, in the temperature range 250-150 K. We focus our attention on orientational relaxations that shift from 0.5 MHz at 250 K to less than 1 Hz at 150 K. The measurements distinguish the relaxation of the hydroxyl groups at the surface of silica from the orientational dynamics of hydration water which strongly depends on the degree of hydration. Although it is significantly faster than the dynamics of water in ice, the orientational relaxation of “non-freezing” water has an activation energy comparable to that in ice when the hydration layer is complete and approximately two-molecule thick

Nanocomposite MCM-41 ("LUS") / ceramic membranes

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Nanocomposite MCM-41 ("LUS") / ceramic membranes

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Catalyse bioinspirée : phtalocyanines supportées

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Bioinspired catalysis : supported phthalocyanines

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Chimie de coordination bio-inspirée et catalyse hétérogène : phtalocyanines greffées sur des silices nanostructurées

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Synthesis and characterization of nanocomposite MCM-41 ('LUS') ceramic membranes

Hamad, B. Alshebani, A. Pera-Titus, M. Wang, S. Torres, M. Albela, B. Bonneviot, L. Miachon, S. Dalmon, J. -A. 4th International Zeolite Membrane Meeting JUL 22-25, 2007 Zaragoza, SPAIN Sp. Iss. SIA new type of nanocomposite membranes, MCM-41 ('LUS')-based material networks grown into porous ceramic membrane support walls (alumina and zirconia), were prepared. Physical characterization (low-angle XRD, TPD, SEM-EDX) confirm the sole presence of the LUS mesostructure (BJH pore size approximate to 3.2 nm), and in a high enough amount to plug the pores of the tubular supports. Single gas hydrodynamic characterization shows that the contribution of defects (i.e. viscous flux) is negligible or comparable to reference mesoporous commercial membranes (5 nm pore size gamma-alumina), but with a considerably enhanced permeance for gases and water, as well as, a single pore size. When compared to literature results on similar organized mesoporous membranes, this work shows even greater improvements. (C) 2008 Elsevier Inc. All rights reserved