Designing and recasting LHC analyses with MadAnalysis 5

We present an extension of the expert mode of the MadAnalysis 5 program dedicated to the design or reinterpretation of high-energy physics collider analyses. We detail the predefined classes, functions and methods available to the user and emphasize the most recent developments. The latter include the possible definition of multiple sub-analyses and a novel user-friendly treatment for the selection criteria. We illustrate this approach by two concrete examples: a CMS search for supersymmetric partners of the top quark and a phenomenological analysis targeting hadronically decaying monotop systems.Comment: 17 pages, 3 figures, 10 tables; version accepted by EPJ

Friction stir welding of AZ31 magnesium alloy rolled sheets: Influence of processing parameters

The temperature evolution during friction stir welding (FSW) and the resulting residual stresses of AZ31 Mg alloy were studied to get a better understanding of the mechanisms involved in this process. The relationship between the processing parameters, the heat and plastic deformation produced and the resulting microstructure and mechanical properties was investigated. Increasing the shoulder diameter or the tool rotation speed or decreasing the welding speed produced an increase in the heat generated during the process and then promoted grain growth. The temperature distribution on the advancing side and on the retreating side differed, and stress levels were higher on the retreating side. The grain size heterogeneity produced by FSW was not the prevailing cause of failure.AEROMAG Project N°AST4-CT-2005-516152 European Unio

Microbial solvent regeneration in biotreatment of air contaminated by styrene

[Abstract] In this study, the biodegradation of a styrene-polluted waste gas in a reactor containing 5 L of a biphasic mixture (10:90% v/v) of organic solvent (silicone oil) – water – biomass was investigated to establish the ability of a microbial solvent regeneration. Reproducible microbial solvent regenerations have been observed. The regeneration time, which increases with the increase of the styrene load (varying from 543 to 1800 mg), leads to elimination capacity up to 48 gstyrene.m-3 mixture.h-1. The solvent regeneration requires roughly 1.2 molecule of oxygen per molecule of styrene and corresponds to the first steps of the biodegradation of the styrene

Geophysical investigation of the Pb-Zn deposit of Lontzen-Poppelsberg, Belgium

The drillhole information from the Lontzen-Poppelsberg site has demonstrated three orebodies and has allowed the estimation of the extension of the lodes, their dip, and the location at the ground surface. The localisation of the lodes makes them excellent targets for further exploration with geophysics. This deposit is classified as a Mississippi Valley Type (MVT) deposit. It consists mainly of Pb-Zn-Fe sulphides that display contrasting values in resistivity, chargeability, density, and magnetic susceptibility, with regards to the sedimentary host rocks. The dipole-dipole direct current (DC) resistivity and induce polarization (IP) profiles have been collected and inverted to successfully delineate the Pb-Zn mineralization and the geological structures. Short-spacing EM34 electromagnetic conductivity data were collected mainly on the top of Poppelsberg East lode and have revealed a conductive body matching with the geologically modelled mineralization. Gravity profiles have been carried out perpendicularly to the lode orientation; they show a strong structural anomaly. High resolution ground magnetic data were collected over the study area, but they showed no anomaly over the ore deposits. The geophysical inversion results are complementary to the model based on drill information, and allow us to refine the delineation of the mineralization. The identification of the geophysical signatures of this deposit permits targeting new possible mineralization in the area

Mass transfer coefficients of styrene into water/silicone oil mixtures: New interpretation using the "equivalent absorption capacity" concept.

International audienceThe physical absorption of styrene into water/silicone oil systems at a constant flow rate for mixtures of different compositions (silicone oil volume fraction ϕ = 0%, 1%, 2%, 3%, 4%, 5%, 6%, 8%, and 10%) was investigated in laboratory-scale bubble reactors using a dynamic absorption method. Experimental results previously analyzed assuming no contact between gas and silicone oil [10] were reconsidered by applying the "equivalent absorption capacity" concept characterized by the value of the styrene partition coefficient between air and the mixture (Hmix). The results indicate that silicone oil addition slightly hinders the styrene mass transfer rate compared to the air/water system. Moreover, a dramatic decrease in KLa values due to silicone oil addition is observed. In comparison with similar measurements available in the literature, it is noted that this decrease in KLa value could be related to the change in the partition coefficient ratio mR = Hwater/Hoil. Two explanations concerning the relationship between the change in a hydrodynamic parameter (KLa) and that in a thermodynamic parameter (mR) are proposed. Finally, it appears questionable to study the change in KLa in terms of silicone oil addition

Friction stir welding of AZ31 magnesium alloy rolled sheets: Influence of processing parameters

International audienceThe temperature evolution during friction stir welding (FSW) and the resulting residual stresses of AZ31 Mg alloy were studied to get a better understanding of the mechanisms involved in this process. The relationship between the processing parameters, the heat and plastic deformation produced and the resulting microstructure and mechanical properties was investigated. Increasing the shoulder diameter or the tool rotation speed or decreasing the welding speed produced an increase in the heat generated during the process and then promoted grain growth. The temperature distribution on the advancing side and on the retreating side differed, and stress levels were higher on the retreating side. The grain size heterogeneity produced by FSW was not the prevailing cause of failure

Mass Transfer Characteristics in Gas-liquid-liquid System

Experimental results of mass transfer in air-water system with a dispersed immiscible organic liquid in a bubble column 0.076 m in diameter for seven different organic liquids at various hold-up are presented. Experiments are carried out at gas superficial velocity in the range 0.0052-0.026 m/s at 293 K. The volumetric mass transfer coefficient, kLa is determined by dynamic gas absorption technique. Overall gas hold-up is also measured. Slight addition of n-decane, dodecane and n-heptane in air-water medium significantly enhances mass transfer from the gas phase, to the continuous aqueous phase whereas toluene, anisole and 2-ethyl- 1-hexanol retard mass transfer

Absorption of toluene in silicone oil: effect of the solvent viscosity on hydrodynamics and mass transfer

International audienceThe purpose of this study was to compare toluene absorption performances using two PDMS of different viscosities (η = 5 and 50 mPas respectively) in terms of hydrodynamics and mass transfer. Three types of packing were tested in a counter-current packed gas-liquid contactor, Raschig rings, IMTP®, and Flexipac®. Hydrodynamic results showed that the viscosity of PDMS 50 is not a hurdle to be used with IMTP® or Flexipac®; the pressure drop being around 288 Pa m−1 for Flexipac® at the flooding point (FG = 0.99 Pa1/2; L’ = 4.95 kg m−2 s−1), which corresponds to an acceptable value for an industrial application. The determination of the loading zones showed that Raschig rings were not suitable for solvents having a high viscosity, such as PDMS 50; they resulted in high pressure drops if compared to IMTP® and Flexipac®. The mass transfer study showed that 100% removal efficiency can be reached for both PDMS using Flexipac®. For IMTP®, the removal efficiency is limited to 88% in the presence of PDMS 50. As a result, PDMS 50 should be a relevant absorbing liquid for the removal of toluene in the absorption–biodegradation process, and Flexipac® packing should be preferred to IMTP