Search results for " PET"

A CO2-gas precursor to the March 2015 Villarrica volcano eruption

2017

We present here the first volcanic gas compositional time-series taken prior to a paroxysmal eruption of Villarrica volcano (Chile). Our gas plume observations were obtained using a fully autonomous Multi-component Gas Analyser System (Multi-GAS) in the 3 month-long phase of escalating volcanic activity that culminated into the 3 March 2015 paroxysm, the largest since 1985. Our results demonstrate a temporal evolution of volcanic plume composition, from low CO$_2$/SO$_2$ ratios (0.65-2.7) during November 2014-January 2015 to CO$_2$/SO$_2$ ratios up to ≈ 9 then after. The H$_2$O/CO$_2$ ratio simultaneously declined to <38 in the same temporal interval. We use results of volatile saturatio…

X-ray tomographic method for measuring three-dimensional deformation and water content distribution in swelling clays

2015

A non-invasive method for simultaneous measurement of the 3D displacement field and the water content distribution of a wetted solid material is developed. The method is based on comparison of X-ray tomographic images of a material sample in the reference state and in the wetted and deformed state. The deformation and water content analyses were successfully compared with numerical results for a cylindrical rubber test sample under axial compression, and with gravimetric results from axially wetted and sliced cylindrical bentonite samples, respectively. The methods were applied in a 4D study (three spatial dimensions and time) of wetting and deformation of purified swelling bentonite doped …

There is something wrong in Britain : televisiosarja Auf Wiedersehen, Pet:in antama kuva Britannian yhteiskunnasta vuosina 1979-1985

2007

Exister au travers de son management ou manager au travers de son existence?
 L’éthique au service de l’entreprise PETRO-ACT

2013

Cette étude de cas porte sur le groupe pétrolier Pétro’Act qui compte environ 47 963 agents en 2010, répartis par fonction comme suit : 55% dans les fonctions coeur de métier, 23% dans les fonctions de soutien et 22% dans les fonctions de support. En 2010, suite à l’ouverture d’une information judicaire : huit directeurs de la compagnie pétrolière, incluant le président-directeur général (PDG), sont sous une enquête de corruption et ont été licenciés et remplacés. L’entreprise désormais bénéficie d’une réputation très dégradée. En effet, le scandale avait éclaté en Janvier 2010 et porte sur les contrats de gré à gré accordés aux groupes internationaux pour des équipements de contrôle et de …

Photoluminescence properties of S2 molecule trapped in Melanophlogite

2015

We studied the photoluminescence properties of a sample of SiO2-clathrate Melanophlogite, a crystalline microporous material which is found in nature as a rare mineral. Upon β irradiation, the material displays an intense light emission under near-UV illumination. We studied in detail this optical activity by steady-state and time-resolved photoluminescence measurements as a function of temperature. The spectroscopic properties we find can be ascribed to a population of quasi-free molecules trapped within each of the two different types of cage available in the structure of this clathrate, although the spectroscopic properties of the guest molecules are affected by their interactions with t…

Stable carbon and oxygen isotope fractionation in bivalve (Placopecten magellanicus) larval aragonite

2008

Abstract The relationship between stable isotope composition (δ13C and δ18O) in seawater and in larval shell aragonite of the sea scallop, Placopecten magellanicus, was investigated in a controlled experiment to determine whether isotopes in larval shell aragonite can be used as a reliable proxy for environmental conditions. The linear relationship between δ13CDIC and δ13Caragonite (r2 = 0.97, p  δ 13 C DIC = 1.15 ( ± 0.05 ) ∗ δ 13 C aragonite - 0.85 ( ± 0.04 ) The relationship between δ13CDIC and δ13Caragonite described for P. magellanicus resulted in larval shell aragonite that was depleted on average by 1.82‰ (SD = 0.22‰, range = 1.1–2.1‰) from predicted equilibrium values based on the r…

Глациоструктура и ледниковый морфогенез (на примере Средней Прибалтики) : Диссертация на соискание ученой степени доктора географических наук : 11.00…

1989

Italica (Seville, Spain): use of local marble in Augustan age

2010

This study concerns 51 marble finds made of “Cipollino verde” coming from the ancient city of Italica (north of the modern city of Santiponce, 9 km NW of Seville, Spain), the earliest Roman settlement in Spain, founded in 206 B.C. The aim of this work was to determine their provenance from Greek and Italian quarries or from local quarries worked in the Iberian Peninsula. Thin-section optical microscopy, X-ray powder diffraction, bulk rock chemistry and O, C and Sr stable isotope analyses were carried out. Results were compared with literature data on “Cipollino verde” marbles quarried in southern Euboea (Greece), Apuan Alps (Italy), Almería, Extremoz, Seville (Spain) and Évora (Portugal). T…