Nîmes – Le Florian

Date de l'opération : 1997 (SD) ; 1998 (SU) Inventeur(s) : Piskorz Michel (AFAN) Plan général des opérations intra muros de Nîmes (Fig. n°5 : En noir, les principales fouilles réalisées entre 1965 et 1990 à l’intérieur de la ville du Haut-Empire, associées à quelques grands repères topographiques). Cette intervention et son diagnostic préliminaire ont été réalisés en préalable à la construction d’une HLM au 30, avenue Georges-Pompidou (EH-304). Le site est établi sur le piémont, à la base du..

Les relations entre la France et les îles anglo-normandes de la fin du XIXe siècle au milieu du XXe siècle. Un épisode majeur : l'immigration française à Jersey de 1850 à 1950

Dans le domaine des sciences humaines, très peu de travaux de recherche ont été consacrés aux îles anglo-normandes, tant en France qu'en Angleterre. En France, dans les publications du dernier demi-siècle, on recense un ouvrage qui traite de l'Occupation allemande des îles entre 1940 et 1945, et deux thèses de droit qui se penchent sur certaines particularités du droit insulaire. Une thèse universitaire, publiée en 1951, s'intéresse à l'agriculture pratiquée à Jersey. En Angleterre, ce..

Life Cycle Inventory for Use of Waste Solvent as Fuel Substitute in the Cement Industry - A Multi-Input Allocation Model (11 pp)

Background: The Swiss chemical industry produces large amounts of organic waste solvents. Some of these solvents cannot be recovered. A common option for the treatment of such organic waste solvents is the incineration in hazardous waste incinerators. Alternatively, the waste solvents can be used as fuel in cement production. On the one hand, solvent incineration in cement kilns saves fossil fuels such as coal and heavy fuel oil. On the other hand, fuel-bound emissions may change as well. These emission changes can either have a negative or a positive net ecological impact, depending on the chemical nature of the waste solvent used. Goal and Scope: The aim of our work was to develop a multi-input allocation model, which allows one to calculate life cycle inventories for specific waste solvents. These LCIs can then be used in further applications, e.g. a comparison of different waste solvent treatment options. Results and Discussion: A multi-input allocation model was developed that takes into account the physico-chemical properties of waste solvents such as elementary composition and net calorific value. The model is based on a set of equations and data on fuel mix, fuel composition as well as transfer coefficients for heavy metals. The model calculates "avoided inputs” and "changes in emissions” which arise from substituting fossil fuels with waste solvents. Life cycle inventories can be calculated for specific waste solvents if the elementary composition and the net calorific value are known. The application of the model is illustrated in a case study on four waste solvents. The results show that solvent incineration in cement kilns generally reduces the overall impact of clinker production because fossil fuels are replaced. A sensitivity analysis revealed that the model is especially sensitive to the fuel mix and coal properties, such as net calorific value as well as the content of nitrogen and carbon. The transfer coefficients are also uncertain, but this uncertainty is not relevant as the amount of heavy metal emitted into the atmosphere is small. Conclusions and Outlook: The proposed model serves to calculate inventory data for the combustion of liquid alternative fuels such as waste solvents in cement kilns. Although our model represents Swiss cement production conditions, it can be applied to other countries by fitting the most sensitive parameters of fuel mix and coal properties. In case the technology used is very different to the Swiss situation, the transfer coefficients also need to be adapte

Local order around rare earth ions during the devitrification of oxyfluoride glasses.

International audienceErbium L(3)-edge extended x-ray absorption fine structure (EXAFS) measurements were performed on rare earth doped fluorosilicate and fluoroborate glasses and glass ceramics. The well known nucleating effects of erbium ions for the crystallization of cubic lead fluoride (based on x-ray diffraction measurements) and the fact that the rare earth ions are present in the crystalline phase (as indicated by Er(3+) emission spectra) seem in contradiction with the present EXAFS analysis, which indicates a lack of medium range structural ordering around the Er(3+) ions and suggests that the lead fluoride crystallization does not occur in the nearest neighbor distance of the rare earth ion. Molecular dynamics simulations of the devitrification process of a lead fluoride glass doped with Er(3+) ions were performed, and results indicate that Er(3+) ions lower the devitrification temperature of PbF(2), in good agreement with the experimental results. The genuine role of Er(3+) ions in the devitrification process of PbF(2) has been investigated. Although Er(3+) ions could indeed act as seeds for crystallization, as experiments suggest, molecular dynamics simulation results corroborate the experimental EXAFS observation that the devitrification does not occur at its nearest neighbor distance

Vers un métamodèle pour analyser les systèmes d’élevage extensifs et leurs interactions avec les territoires

Nous proposons un canevas souple et adaptable pour faciliter la conception rapide de modèles permettant d’aborder la durabilité des systèmes d’élevage extensif à l’échelle de territoires. Ce métamodèle est le fruit d’une démarche de conception à partir de systèmes multi-agents (SMA) développés sur sept sites en Amérique latine, en France et au Sénégal. Il est composé de quatre modules : Agent, Collectivité, Espace, Végétation-troupeau. Nous les illustrons par les exemples tirés des modèles élaborés sur les différents sites. Le rôle de cet outil est discuté afin d’en montrer les avantages et les limite

Nîmes – Introduction

Inventeur(s) : Compan Michel ; Hervé Marie-Laure (AFAN) ; Veyrac Alain ; Pène Jean-Michel Une archéologie de la ville et des campagnes La commune de Nîmes (Gard) intègre, du nord vers le sud, des unités géographiques distinctes : la zone des Garrigues qui s'achève, au contact de la ville antique, par une série de collines de faible altitude dessinant une sorte de théâtre naturel, un piémont qui descend en pente douce vers le sud-est, sur une emprise de 1 à 2 km, la plaine alluviale du Vistre,..

Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions

Data taken with the ALEPH detector at LEP1 have been used to search for gamma gamma production of the glueball candidates f0(1500) and fJ(1710) via their decay to pi+pi-. No signal is observed and upper limits to the product of gamma gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) < 0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV at 95% confidence level.Comment: 10 pages, 3 figure

Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81 GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the 95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure

Search for CP Violation in the Decay Z -> b (b bar) g

About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, ${\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab}$ and $h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}$, limits of \hat{h}_b < 0.59$and$h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st