Search results for "MOS"
showing 10 items of 10534 documents
Chemical Cartography with APOGEE: Multi-element Abundance Ratios
2019
We map the trends of elemental abundance ratios across the Galactic disk, spanning R = 3-15 kpc and midplane distance |Z|= 0-2 kpc, for 15 elements in a sample of 20,485 stars measured by the SDSS/APOGEE survey (O, Na, Mg, Al, Si, P, S, K, Ca, V, Cr, Mn, Fe, Co, Ni). Adopting Mg rather than Fe as our reference element, and separating stars into two populations based on [Fe/Mg], we find that the median trends of [X/Mg] vs. [Mg/H] in each population are nearly independent of location in the Galaxy. The full multi-element cartography can be summarized by combining these nearly universal median sequences with our measured metallicity distribution functions and the relative proportions of the lo…
The Gaia-ESO Survey: impact of extra mixing on C and N abundances of giant stars
2018
The GES survey using FLAMES at the VLT has obtained high-resolution UVES spectra for a large number of giant stars, allowing a determination of the abundances of the key chemical elements C and N at their surface. The surface abundances of these chemical species are well-known to change in stars during their evolution on the red giant branch after the first dredge-up episod, as a result of extra-mixing phenomena. We investigate the effects of thermohaline mixing on C and N abundances using the first comparison between the GES [C/N] determinations with simulations of the observed fields using a model of stellar population synthesis. We explore the effects of thermohaline mixing on the chemic…
Starzenie i biodegradacja kompozytów polimerowo-drzewnych
2012
The weathering test of polypropylene composites
2000
Polipropylen "Malen P" czysty (a), kompozyty na jego podstawie napełniane (20% mas.) kredą lub talkiem (b) oraz produkty te stabilizowane dodatkowo stabilizatorem UV typu HALS ("Tinuvin 791") (c) poddano badaniom laboratoryjnego starzenia atmosferycznego. Badane próbki poddawano działaniu promieniowania ultrafioletowego w dawkach do 950 MJ/m2, w zaprogramowanych warunkach temperatury, wilgotności oraz nadeszczania. Postęp fotodegradacji polimeru śledzono na podstawie zmian ciężaru cząsteczkowego, jego rozkładu (GPC) oraz wybranych właściwości mechanicznych (wydłużenia względnego, naprężenia zrywającego, udarności z karbem). Określono również odporność próbek badanych białych kompozytów na z…
Mandibular metastasis from carcinoma of the bladder: Report of a case and literature review
2022
Metastases represent about 1% of all malignant tumors of the oral region. Only 12 cases of metastases to the jawbones and 3 to the oral soft tissues from a carcinoma of the bladder are reported in the English literature. Here we report a case of an 86 year-old man with a metastasis to the anterior region of the lower jaw from a transitional cell carcinoma of the bladder treated 5 years before, all-together with a literature review.
Dynamique fluvial, changement global et pression anthropique dans le bassin, le cours et le delta de l'Ébre
2017
Le fonctionnement des rivières du bassin de l’Èbre a subi d’importants changements depuis 1950. Il s’agit d’un processus rapide et très marqué, de simplification et de stabilisation sur le fleuve principal et sur ses principaux affluents pyrénéens. Ce processus s’est manifesté par des changements dans la morphologie fluviale, le développement de la végétation sur les lits, un rétrécissement de l’espace naturel fluvial et une incision des lits fluviaux. Les facteurs de ce processus sont le changement global dans le bassin, la construction de réservoirs d’eau et d’autres nombreuses pressions humaines directes, notamment d’extractions de graviers et de canalisations. Le delta de l’Èbre, actuel…
In situ measurements of background aerosol and subvisible cirrus in the tropical tropopause region
2002
[1] In situ aerosol measurements were performed in the Indian Ocean Intertropical Convergence Zone (ITCZ) region during the Airborne Polar Experiment-Third European Stratospheric Experiment on Ozone (APE-THESEO) field campaign based in Mahe, Seychelles between 24 February and 6 March 1999. These are measurements of particle size distributions with a laser optical particle counter of the Forward Scattering Spectrometer Probe (FSSP)-300 type operated on the Russian M-55 high-altitude research aircraft Geophysica in the tropical upper troposphere and lower stratosphere up to altitudes of 21 km. On 24 and 27 February 1999, ultrathin layers of cirrus clouds were penetrated by Geophysica directly…
Papel del sueño en el desarrollo de obesidad infantil
2021
El sobrepeso y la obesidad infantil suponen uno de los mayores problemas de salud a nivel mundial, incrementándose su incidencia en las últimas décadas. Esto acarrea la aparición de diversos problemas en el desarrollo, así como de varias patologías comórbidas durante la edad adulta, empeorando la calidad de vida y comportando un gran gasto económico para los sistemas nacionales de salud. La obesidad generalmente se ha visto asociada a la adopción de hábitos dietéticos no saludables y a una reducción de la actividad física diaria, derivada de un aumento del sedentarismo. No obstante, las terapias asociadas a la mejora de este estilo de vida no han resultado tener el éxito esperado. Ahora bie…
Spherical Top Theory and Molecular Spectra
2011
In this article, we present an overview of the present state of the art of the theory of high-resolution spherical-top spectra in the framework of the effective Hamiltonian approach. We describe the specific features of this class of molecules to explain the basic concepts of the theoretical methods used for the analysis (line positions and intensities) and the simulation of absorption (including pure rotation) and Raman spectra of such species. The non conventional formalism that we use is essentially based on irreducible tensor methods and is especially adapted to computational treatments and global analyses of complex interacting band systems. We give examples concerning mainly methane (…
Holocene Spatiotemporal Redox Variations in the Southern Baltic Sea
2021
Low oxygen conditions in the modern Baltic Sea are exacerbated by human activities; however, anoxic conditions also prevailed naturally over the Holocene. Few studies have characterized the specific paleoredox conditions (manganous, ferruginous, euxinic) and their frequency in southern Baltic sub-basins during these ancient events. Here, we apply a suite of isotope systems (Fe, Mo, S) and associated elemental proxies (e.g., Fe speciation, Mn) to specifically define water column redox regimes through the Baltic Holocene in a sill-proximal to sill-distal transect (Lille Belt, Bornholm Basin, Landsort Deep) using samples collected during the Integrated Ocean Drilling Program Expedition 347. At…