Gravitational-wave tail effects to quartic non-linear order

Gravitational-wave tails are due to the backscattering of linear waves onto the space-time curvature generated by the total mass of the matter source. The dominant tails correspond to quadratic non-linear interactions and arise at the one-and-a-half post-Newtonian (1.5PN) order in the gravitational waveform. The "tails-of-tails", which are cubic non-linear effects appearing at the 3PN order in the waveform, are also known. We derive here higher non-linear tail effects, namely those associated with quartic non-linear interactions or "tails-of-tails-of-tails", which are shown to arise at the 4.5PN order. As an application, we obtain at that order the complete coefficient in the total gravitational-wave energy flux of compact binary systems moving on circular orbits. Our result perfectly agrees with black-hole perturbation calculations in the limit of extreme mass ratio of the two compact objects.Comment: 32 pages, no figure, matches with published versio

Flood event impact on pesticide transfer in a small agricultural catchment (Moutousse at Aurade, south west France)

In this paper, pesticide transfer dynamic is studied during two flood events in a small experimental catchment close to Toulouse (south west France). Thirteen pesticide molecules (herbicides, fungicides) have been analysed by multi-residue technique on filtered and unfiltered waters. The results show very high pesticide concentrations in the different fractions compared to low flow periods and to the data collected by the French institutional networks in charge of the pesticide river water pollution survey. Several molecules present concentration higher than 0.1 mgL-1 and even higher than 1 mgL-1 in the unfiltered waters. In the suspended matters the concentrations vary respectively between 0.1 and 30 mg g-1 according to the molecules and can represent 40 to 90% of the total concentration for low soluble molecules. All the molecule concentrations and fluxes increase during the flood flows and have positive relationships with the stream discharge, but hysteresis between rising and falling periods can be observed for some molecules. Pesticide concentrations in unfiltered waters and partitioning between dissolved and particulate fractions (Kd¼[diss]/[part]) are controlled by dissolved organic carbon and total suspended matter. A good negative relationship can be established between logKd and logKow for 6 molecules

Étude des qualifications des contraintes et trajectoires centrales issues d'algorithmes de barrière logarithmique

Ce mémoire fait une revue du concept de qualification des contraintes de premier et deuxième ordre. Les qualifications de premier ordre les plus connues et utilisées sont présentées, ainsi que des exemples et contre-exemples qui mettent en évidence les relations entre elles. Leurs équivalences dans les problèmes convexes sont aussi mises en évidence. Quelques qualifications de second ordre, ainsi que certains contre-exemples, sont présentés. Finalement, les fondations d'un travail visant à alléger les hypothèses essentielles à l'existence de trajectoires centrales d'algorithmes de barrière logarithmique sont présentées

Les qualifications des contraintes en optimisation à contraintes non linéaires

Cet article consiste en une vulgarisation du concept de qualification des contraintes du premier ordre dans un programme d’optimisation non linéaire. Des exemples de problèmes explicitant les différences entre plusieurs qualifications sont énoncés, permettant de mieux visualiser ce qu’impliquent ces qualifications. Les relations entre trois qualifications sont approfondies, c’est-à-dire l’indépendance linéaire (LICQ), la qualification de Mangasarian- Fromovitz (MFCQ) et la condition du rang constant (CRCQ). D’autres qualifications de nature plus analytique sont ensuite présentées

Statistical analysis of concrete transport properties

Results of a statistical analysis of transport properties measurements carried out on a number of concrete mixtures are presented. Migration and drying experiments were performed to evaluate the ionic diffusion coefficients and permeability of concrete mixtures. Seven concrete mixtures were tested. The mixtures were either batched under laboratory conditions or sampled from construction sites. For each mixture, approximately eighty concrete samples from a single batch were tested. Ionic diffusion coefficients were calculated by analyzing the evolution of the electrical current passing through concrete samples during the migration tests. Calculations took into account the volume of permeable pores of the materials and the pore solution chemistry. Permeability was calculated from mass loss measured during drying tests. The study indicates that the coefficient of variation of ionic diffusion coefficients is 11.1 % on average, with a maximum of 23.5 %, and that the coefficient of variation of permeability is 20.6 % on average, with a maximum of 37.3 %

Sensitivity of chloride ingress modelling in concrete to input parameter variability

The Rosenblueth point estimator method is used to propagate uncertainty on stochastic parameters in a multi-ionic reactive transport model for concrete degradation. The degradation mechanism that was analysed is the ingress of chlorides into concrete. This point estimator method is used because it requires a minimum number of simulations to compute means, standard deviations and skewness for the solution of the transport model. Two exposure cases are considered in this article: the first is a saturated case, and the second is an unsaturated case with wetting (4 days) and drying (3 days at 50 % relative humidity) cycles. The sodium chloride exposure during the wetting cycle of both cases was 500 mmol/L. In both cases, predictions from the model were compared to experimental results. The Rosenblueth approach yielded results comparable to Monte Carlo simulations for both saturated and unsaturated cases. The relative sensitivity of model parameters on prediction results are investigated through a sensitivity analysis. The sensitivity results show the high importance of ionic diffusion parameters and of exposure conditions, while the calculated initial mineral phases in the hydrated paste have lower importance

Quantification of levoglucosan and its isomers by High Performance Liquid Chromatography - Electrospray Ionization tandem Mass Spectrometry and its application to atmospheric and soil samples

http://www.atmos-meas-tech-discuss.net/4/4539/2011/amtd-4-4539-2011.htmlInternational audienceThe determination of atmospheric concentrations of levoglucosan and its two isomers, unambiguous tracers of biomass burning emissions, became even more important with the development of wood as renewable energy for domestic heating. Many researches demonstrated the increase during recent years of atmospheric particulate matter load due to domestic biomass combustion in developed countries. Analysis of biomass burning tracers is traditionally performed with Gas Chromatography-Mass Spectrometry (GC-MS) technique after derivatization and requires an organic solvent extraction. A simpler and faster technique using Liquid Chromatography - Electrospray Ionisation - tandem Mass Spectrometry (LC-ESI-MS/MS) was optimized for the analysis of levoglucosan, mannosan and galactosan isomers after an aqueous extraction. This technique allows a good separation between the three compounds in a very reduced time (runtime ~5 min). LOD and LOQ of this method are 30 μg l−1 and 100 μg l−1 respectively, allowing the use of filters from low-volume sampler (as commonly used in routine campaigns). A comparison of simultaneous levoglucosan measurements by GC-MS and LC-ESI-MS/MS for about 50 samples coming from different types of sampling sites and seasons was realized and shows very good agreement between the two methods. Therefore LC-ESI-MS/MS method can be used as an alternative to GC-MS particularly for measurement campaigns in routine where analysis time is important and detection limit is reduced. This paper shows that this method is also applicable to other environmental sample types like soil

Development of air and dust sampling methods for quantitative measurements of polybromated diphenyl ethers (PBDEs) in offices

International audienc