334 research outputs found
21. -Le dossier hydraulique de Nîmes après le 3 octobre 1988
No full textDepuis le 3 octobre 1988, d'autres épisodes pluvieux ont provoqué des débordements en ville.
Une commission hydraulique municipale a proposé des solutions techniques début 1989. Un comité de pilotage présidé par le Préfet du Gard les a avalisé.
Administrativement : après 2 enquêtes publiques, une Déclaration d'intérêt Général a été prononcée le 10 septembre 1993. Depuis, la ville présente cadereau par cadereau des enquêtes de D.U.P. et Hydraulique.
La solution retenue : de l'amont vers l'aval : bassins et carrières, fossés à ciel ouvert, traversée de la ville en souterrain, fossés aval à ciel ouvert avec bassins de rétention latéraux pour limiter les débits arrivant au Vistre.
Financement : coût global 670 MF. Recherche des subventions - Programmation.
Le phénomène pluvieux subi par Nîmes le 3 octobre 1988 s'est traduit par 10 morts, 3 milliards de dégâts, une ville dévastée.Fabre G., Scheurer P., Lequeux J.-M. 21. -Le dossier hydraulique de Nîmes après le 3 octobre 1988. In: Crues et inondations. 23èmes journées de l'hydraulique. Congrès de la Société Hydrotechnique de France. Nimes (France), 14-15-16 septembre 1994. Tome 2, 1994
Results of the ESO-SEST Key Programme: CO in the Magellanic Clouds. V. Further CO observations of the Small Magellanic Cloud
No full textArtículo de publicación ISIWe present further results of fully-sampled observations in the J = 1!0 and J = 2!1 rotational
transitions of 12CO and 13CO, obtained with the SEST telescope at 43
00
or 22
00
resolution, toward the Small Magellanic
Cloud. These observations concern six molecular clouds with a variety of physical conditions. Maps in the 12CO(1!0),
12CO(2!1), and in some cases of 13CO(1!0) lines are presented, as well as pro les of the four lines at the peak
positions convolved to the same angular resolution of 43
00
. The line ratio results are interpreted in Paper IV of this
series (Lequeux et al. 1994)
Multiwavelength observations of N 66 in the SMC: unveiling photodissociation interfaces and star formation
No full textWe present new observations of the major star-forming region N66 in the Small Magellanic Cloud and of its surroundings, which add to those presented in Contursi et al. (2000, Paper I). High-sensitivity CO observations allowed the detection of molecular gas associated with the H II region, for which a high-resolution image in [O III] lambda 5007 is presented. We also present images in the v(1-0) S(1) line of H-2 at 2.12 mu m and in the adjacent continuum. This material reveals an interesting photodissociation region. We show that the molecular gas that has not yet been photodissociated by the UV radiation of the stars is in hot, dense clumps with a very small surface filling factor. We discovered several embedded stars or stellar associations, and suggest that three successive stellar generations have already taken place in less than 3 million years
Results of the ESO-SEST Key Programme: CO in the Magellanic Clouds. V. Further CO observations of the Small Magellanic Cloud
No full textWe present further
results of fully-sampled observations in the and
rotational
transitions of and , obtained with the SEST telescope at
43″ or 22″ resolution, toward the Small Magellanic Cloud.
These observations concern six molecular
clouds with a variety of physical conditions. Maps in the
,
and in some cases of lines are presented, as well as
profiles of the four lines at the peak positions convolved to the same angular
resolution of . The line ratio results are interpreted in Paper IV of this
series (Lequeux et al. 1994)
Resonant translational, breathing and twisting modes of pinned transverse magnetic domain walls
No full textWe study translational, breathing and twisting resonant modes of transverse magnetic domain walls pinned at notches in ferromagnetic nanostrips. We demonstrate that a mode's sensitivity to notches depends strongly on the characteristics of that particular resonance. For example, the frequencies of modes involving lateral motion of the wall are the ones which are most sensitive to changes in the notch intrusion depth (especially at the narrower, more strongly confined end of the domain wall). In contrast, the breathing mode, whose dynamics are concentrated away from the notches is relatively insensitive to changes in the notches' sizes. We also demonstrate a sharp drop in the translational mode's frequency towards zero when approaching depinning which is found, using a harmonic oscillator model, to be consistent with a reduction in the local slope of the notch-induced confining potential at its edge
Intérêt astrophysique de la spectroscopie moléculaire hertzienne
No full textDepuis la découverte des raies radio de OH en 1963, l'étude radio des molécules interstellaires est devenue un des chapitres les plus importants de l'astrophysique. Outre OH et la molécule isotopique O18H, les molécules NH3, H2O, H2CO et la molécule isotopique H2C13O, CO, CN et HCN ont été détectées en radio. CN, CH, CH+, C13H+ et NH3 sont également connues par leurs raies d'absorption optiques. Toutes ces molécules présentent à des degrés divers des écarts à l'équilibre thermodynamique, pouvant même produire des effets masers donnant des intensités énormes, dans le cas de OH et H2O. Elles sont très abondantes dans la Galaxie, ce qui est surprenant car plusieurs sont rapidement dissociées par l'Ultra-violet interstellaire. Leur formation, sans doute à la surface des grains de poussière interstellaires, pose des problèmes de physico-chimie encore mal explorés. Etant donné que ni la fragilité de la molécule dans les conditions interstellaires ni son énergie de formation ne semblent jouer de rôle essentiel dans son abondance, on peut s'attendre à observer toutes les molécules simples formées avec les éléments les plus abondants dans le milieu interstellaire : H, O, N, C, Fe, Mg, Si, S, etc... Cependant la détection de ces molécules est difficile si on ne dispose que de fréquences calculées ou déduites de mesures optiques : la mesure en laboratoire des fréquences hertziennes des transitions intéressantes est une étape indispensable de l'astrophysique moléculaire. Nous avons rassemblé ci-dessous une bibliographie qui, pour OH, ne donne que des titres récents et des articles fondamentaux plus anciens. Elle doit être sensiblement complète pour NH 3, H2O et H2CO. Enfin un certain nombre d'articles relatifs à l'étude optique des molécules interstellaires et à la détection radio de certaines molécules sont également indiqués
Submillimetre molecular line observations and modelling of molecular clouds.
No full textPhDSubmillimetre molecular line observations of molecular clouds in
our galaxy are presented, and the data analysed using various alternative
cloud models.
A critical review is given of the methods commonly used to
interpret molecular line data, including both theoretical considerations
and issues relating to calibration and comparability of results
obtained with different telescopes. A detailed comparison is made
between results predicted from large velocity gradient (LVG) models,
including the generalisation to non-monotonic velocity flows, and
those given by "microturbulent" clouds.
An LVG model is employed in an investigation of conditions in the
molecular outflows frequently found in star formation regions, for
which observations in the CO J=3-2 rotational transition at 345 GHz
are presented. These are combined with lower frequency data from the
literature to derive various properties of the outflows for a sample
of 13 sources. The most important result is that local H2 densities
exist in the outflows which are higher, typically by an order of magnitude,
than previously derived average values obtained using only
lower frequency data.
Observations are presented of the S255 and DR21 clouds in the
transitions CO J=2-1, CO J=3-2, CS J=7-6, HCN J=4-3, HCO+ J=4-3 and
-3-
H13CO+ J=4-3 and are supplemented by continuum data at 350 s. n and
(for DR21) at 20 pm. It is shown that, although some features
of the data can be understood in terms of an LVG model, there is compelling
evidence for fragmentation of the clouds on length scales
much smaller than the cloud sizes. The data are used to constrain
the local H2 densities and relative molecular abundances in the
clumpy cloud cores, and compared with lower frequency results from
the literature.
The implications of these results for the star formation environment
are discussed, and an assessment made of possible strategies
for their further investigation
Static and dynamic contact lines on a deformable coating of controled thickness
No full textInternational audienceFigure: From left to right: (a) drop on a soft substrate (water on PDMS), (b) structure near contact line, (c) non-linear simulations of the shear stress distribution below the contact line, whose intensity is encoded by the colours. Gel layers bound to a rigid substrate are used in cell culture to control differentiation and migration and to lower the friction and tailor the wetting of solids. Their thickness, often considered a negligible parameter, affects cell mechanosensing or the shape of sessile droplets [1]. We show first that the adjustment of thickness provides control over energy dissipation during the spreading of flowing matter on a gel layer [2]. We combine experiments and theory to uncover a scaling law that predicts the dynamic contact angle between the three phases as a function of the properties of the coating and the velocity of the contact line. We also demonstrate that thickness gradients can guide moving droplets. Our study shows that thickness is another parameter, besides surface energy and substrate mechanics, to tune liquid spreading and wetting on compliant coating, with potential applications to dew collection and free-surface film flow control. In a second step, we investigate numerically and theoretically the problem when the slope of the gel surface becomes non-negligible, the material reaching a regime of finite deformations, with non-linearities of geometrical origin. We show that both statics and dynamics are completely modified, a singular force displacing the well-known Neumann balance of forces at contact line [3]. We provide a general framework allowing to develop approximate analytical calculations, and give general laws governing the static and dynamic contact angle in this complex, non-linear regime. [1] J. Dervaux and L. Limat, "Contact lines on soft solids with uniform surface tension: analytical solutions and double transition for increasing deformability", Proc. R. Soc. A 471, 20140813 (2015) [2] M. Zhao, J. Dervaux, T. Narita, F. Lequeux, L. Limat, and M. Roché, "Geometrical control of dissipation during the spreading of liquids on soft solids"
La Vallière, Françoise-Louise de la Beaume le Blanc, duchesse de, en religion Louise de la Miséricorde, carmélite (Tours, 1644 - Paris, 1710)
No full textL'articolo presenta una biografia della carmelitana Louise de la Miséricorde, estrapolata dalla lettura ragionata delle fonti reperite, nel contesto religioso del Grand siècle. Considera e descrive brevemente la prima edizione delle lettere della religiosa, a cura del biografo C. Lequeux, e la successiva edizione (J.-A. Lair), e le edizioni degli altri scritti autografi della religiosa. Seguono il rinvio alla loro collacazione geografica e virtuale e riferimenti bibliografici all'opera della religiosa
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