B. Beaugiraud - Academia.edu (original) (raw)

Papers by B. Beaugiraud

ABSTRACT A novel geometry liquid argon calorimeter with accordion-shaped electrodes and converter... more ABSTRACT A novel geometry liquid argon calorimeter with accordion-shaped electrodes and converter plates has been recently conceived. Such a design allows for a fast readout and for a high granularity over large volumes with minimal dead spaces, properties which are considered essential for operation at the future hadron colliders.The first electromagnetic prototype based on this scheme has been built and tested at the CERN SPS. For a response peaking time of 140 ns an energy resolution of 10%/√E(GeV) and a space resolution of 4.4 mm/√E(GeV) with 2.7 cm cell size were achieved for electrons. A few preliminary results from a test with fast readout (response peaking time of less than 40 ns) are also presented.

PROCEEDINGS OF THE 22ND INTERNATIONAL ESAFORM CONFERENCE ON MATERIAL FORMING: ESAFORM 2019

Applied Surface Science, 2015

Abstract This paper presents the effect of laser texturing on the tribological properties of PEEK... more Abstract This paper presents the effect of laser texturing on the tribological properties of PEEK surfaces under a ball-on-flat contact configuration. Thus, surfaces with circular dimples of various diameters and depth were created. Tests were conducted with a normal load of 5 N and a sliding velocity of 0.01 m s −1 , using bovine calf serum at 37.5 °C as a lubricant. The tribological conditions including the sliding frequency and the lubricant viscosity indicate that tests were performed under boundary lubrication regime. Results showed that discs with higher dimple depth exhibited higher friction coefficient and caused more abrasive wear on the ball specimen. Nevertheless, tribosystems (ball and disc) with dimpled disc surfaces showed a higher wear resistance. In the frame of our experiments, wear rates obtained for tribosystems including dimpled surfaces were 10 times lower than tribosystems including limited patterned or untextured surfaces. Applications such as design of spinal implants may be concerned by such a surface treatment to increase wear resistance of components.

Water science and technology : a journal of the International Association on Water Pollution Research, 2004

The photocatalytic removal rates r of dichloroacetic acid (DCAA), 4-chlorobenzoic acid (4-CBA) an... more The photocatalytic removal rates r of dichloroacetic acid (DCAA), 4-chlorobenzoic acid (4-CBA) and 4-chlorophenol (4-CP) in water were compared for TiO2 samples used either as a powder or as a coating on a fiber glass tissue, SiO2 being the binder. From SEM-EDX measurements it was deduced that SiO2 prevails over TiO2 in the coating top layers and 18O2-Ti16O2 isotopic exchange showed that the accessibility of O2 to TiO2 was markedly reduced when TiO2 was thus coated. The unfavorable effect of the restricted TiO2 accessibility on r was drastic for DCAA, much less pronounced for 4-CBA, and still smaller for 4-CP. It is inferred that DCAA can be attacked only when it directly interacts with TiO2, whereas 4-CP can also react within the near-TiO2 surface water layers. The 4-CBA intermediate behavior is in line with the structural similarities of 4-CBA with DCAA and 4-CP.

Tribology Letters, 2009

ABSTRACT The present investigation focuses on the tribological transformation occurring on a Ti a... more ABSTRACT The present investigation focuses on the tribological transformation occurring on a Ti alloy (Ti17) under fretting in air. Several fretting wear tests were performed on a large scale punch on plane configuration (two types of planes tested: bare Ti6242 and CuNiIn-coated Ti6242) at several temperatures from ambient up to 450°C. In all the cases, two zones were identified on the scars: a lateral oxidized rim and a highly deformed region at centre. Metallurgical observations revealed similarities with Tribologically Transformed Structure (TTS), previously observed on various Ti alloys. In the framework of this article, careful analyses were conducted (EDX, DRX, XPS, HRTEM and EFTEM) in order to identify the nature and chemistry of this transformed layer. Results demonstrated the formation of a new phase, nanocrystalline, identified as TiO x N y . The high content of nitrogen found in the TTS indicated its ability to penetrate inside the contact and react with titanium. At 50μm under the surface, a FIB preparation enabled the observation in TEM of N-rich lamellae (TiO x N y ) in the Ti (α) matrix. Two models were suggested to explain this tribochemical reaction under fretting.

Scanning, 2013

We have investigated femtosecond (fs) laser (130 fs, 800 nm, 5 kHz) ablation of polypropylene (PP... more We have investigated femtosecond (fs) laser (130 fs, 800 nm, 5 kHz) ablation of polypropylene (PP). The following laser process conditions were varied: power density and number of pulses. The morphological parameters' response (depth, ablation diameter, ablation volume) to the laser process conditions, measured by an optical profiler, was investigated by the statistical analysis technique to determine the relationship between them. For this, the simple linear regression and the multiple linear regressions are compared. The simple linear regression shows that the ablation volume follows a linear relationship with the product of the power and the number of pulse. SCANNING 9999:1-9, 2013. © 2013 Wiley Periodicals, Inc.

Applied Surface Science, 2011

Applied Catalysis B: Environmental, 2002

... Chantal Guillard Corresponding Author Contact Information , E-mail The Corresponding Author ,... more ... Chantal Guillard Corresponding Author Contact Information , E-mail The Corresponding Author , Bernard Beaugiraud, Cédric Dutriez, Jean-Marie Herrmann, Henri Jaffrezic ... The crystallinity of TiO 2 coatings was identified by X-ray diffraction (XRD) employing Cu Kα radiation. ...

Express Polymer Letters, 2010

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1997

Conference Record of the 1991 IEEE Nuclear Science Symposium and Medical Imaging Conference, 1991

Summary form only given. A research and development program is being conducted in view of realizi... more Summary form only given. A research and development program is being conducted in view of realizing an electromagnetic and hadronic calorimeter for the Large Hadron Collider (LHC). The authors report on tests on fast electronics, coupled to an electromagnetic prototype calorimeter built with an accordion structure. Three different types of preamplifiers have been used. In two (Si and GaAs hybrids),

Journal of Instrumentation, 2008

... L. and Chen, T. and Chen, X. and Cheng, S. and Cheng, TL and Cheplakov, A. and Chepurnov, VF ... more ... L. and Chen, T. and Chen, X. and Cheng, S. and Cheng, TL and Cheplakov, A. and Chepurnov, VF and El Moursli, R. Cherkaoui and Chesneanu, D. and Cheu, E. and Chevalier, L. and Chevalley, JL and Chevallier, F. and Chiarella, V. and Chiefari, G. and Chikovani, L. and ...

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1993

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1995