Search results for " layer"
showing 10 items of 1022 documents
Mechanical properties of aluminum, zirconium, hafnium and tantalum oxides and their nanolaminates grown by atomic layer deposition
2015
ABSTRACT The mechanical properties of two different metal oxide nanolaminates comprised of Ta 2 O 5 and Al 2 O 3 , HfO 2 or ZrO 2 , grown on soda–lime glass substrate by atomic layer deposition, were investigated. Ta 2 O 5 and Al 2 O 3 layers were amorphous, whereas ZrO 2 and HfO 2 possessed crystalline structure. Thickness of single oxide layers was varied between 2.5 and 15 nm. The total thickness of the laminate structures was in the range of 160–170 nm. The hardness values of single layer oxides on glass ranged from 6.7 GPa (Ta 2 O 5 ) to 9.5 GPa (Al 2 O 3 ). Corresponding elastic moduli were 96 GPa and 101 GPa. The hardnesses of laminates were in the range of 6.8–7.8 GPa and elastic mo…
Manufacturing and characterization of single cell intermediate-temperature solid oxide fuel cells for APU in transportation application
2014
The fabrications of large area IT-SOFC planar cell by new simple and cost effective process were explained. The optimization of the new process with respect to pore formers, thickness of layers, sintering temperature were performed. The electrochemical results of 10cm2 performed in Fiaxell open flange set up were detailed with respect to different configuration. Long term ageing performance tests of single cells were conducted in Fiaxell device and results are discussed. Preparation of new test bench and stacking process performed till now were briefed.
Terpyridine-based metallopolymer thin films as active layer in ammonia sensor device
2016
International audience; A metal-containing polymer has been prepared by electropolymerization of an homoleptic Ru(II)-terpyridine complex bearing pyrrole heterocycles. The polymer is obtained as a thinfilm at the surface ofelectrodes, and has been characterized by electrochemical measurements, XPS and microscopy. It hasbeen shown that this polymer acts as an active gas sensitive layer since it enables the detection of anammonia gasflow through layer’s resistivity measurements.
On the radiative impact of aerosols on photolysis rates: comparison of simulations and observations in the Lampedusa island during the ChArMEx/ADRIME…
2016
The Mediterranean basin is characterized by large concentrations of aerosols from both natural and anthropogenic sources. These aerosols affect tropospheric photochemistry by modulating the photolytic rates. Three simulations of the atmospheric composition at basin scale have been performed with the CHIMERE chemistry-transport model for the period from 6 June to 15 July 2013 covered by the ADRIMED campaign, a campaign of intense measurements in the western Mediterranean basin. One simulation takes into account the radiative effect of the aerosols on photochemistry, the second one does not, and the third one is designed to quantify the model sensitivity to a bias in the ozone column. These s…
Global sea-to-air flux climatology for bromoform, dibromomethane and methyl iodide
2013
Volatile halogenated organic compounds containing bromine and iodine, which are naturally produced in the ocean, are involved in ozone depletion in both the troposphere and stratosphere. Three prominent compounds transporting large amounts of marine halogens into the atmosphere are bromoform (CHBr3), dibromomethane (CH2Br2) and methyl iodide (CH3I). The input of marine halogens to the stratosphere has been estimated from observations and modelling studies using low-resolution oceanic emission scenarios derived from top-down approaches. In order to improve emission inventory estimates, we calculate data-based high resolution global sea-to-air flux estimates of these compounds from surface ob…
Investigation of marine and continental layers in a stalactite older than 1 million years (Custonaci, north-western sector of Sicily)
2012
Questo lavoro si basa sul ritrovamento, in una grotta carsica, a 100 metri di quota a Custonaci in provincia di Trapani, di una stalattite di notevole interesse paleo climatico, ricoperta da coralli marini, la cui sezione rivela la presenza di 3 Iatus che denotano una interruzione della deposizione di carbonato continentale presumibilmente in seguito a trasgressioni marine. Il carbonato, datato attraverso la metodologia 230Th/U MC-ICPMS (NeptunePlus), ha fornito una età più antica del limite temporale massimo di applicabilità del metodo ( 600 ka). I coralli, che ricoprono il livello continentale più giovane, analizzati usando il rapporto 87Sr/86Sr, hanno fornito una età di 1.1±0.2 Myrs. Al…
Quantification of land-atmosphere exchanges of water, energy and carbon dioxide in space and time over the heterogeneous Barrax site
2008
International audience; To advance our understanding of land-atmosphere exchanges of water, energy and carbon dioxide (CO2) in space and time over heterogeneous land surfaces, two intensive field campaigns were carried out at the Barrax agricultural test site in Spain during 12-21 July 2004 (SPARC 2004) and 8-14 July 2005 (SEN2FLEX 2005) involving multiple field, satellite and airborne instruments for characterizing the state of the atmosphere, the vegetation and the soil from the visible to the microwave range of the spectrum. Part of the experimental area is a core site of area 25 km2, within which numerous crops are grown, on both irrigated and dry land, alongside fields of bare soil. Th…
Optimization of Passive Constrained Layer Damping (Pcld) Treatments for Vibration Reduction
2015
An efficient method to reduce the frequency averaged transverse vibration level of aplate by optimizing the position of attached passive constrained layer damping PCLD is presented.This method uses a multilayer anisotropic plate model which is an equivalent single layer platemodel (ESL) where transverse shear stresses and displacements are continuous at each layer’sinterfaces. Hence, for a laminate composed of an arbitrary number of layers, all the quantities arerelated to those of the first layer. The optimization process is based on the use of the ESL platemodel combined with the genetic algorithm (GA) and Latin Hypercube Sampling (LHS) algorithmimplemented in a Rayleigh-Ritz resolution p…
Developing REE parameters for soil and sediment profile analysis to identify Neolithic anthropogenic signatures at Serpis Valley (Spain)
2020
In this study, patterns of rare earth elements (REE) have been developed and applied for the first time to sediments and soils to identify anthropogenic or natural layers in profiles sampled at several Neolithic settlements in the Serpis Valley area (Alicante, Spain). Most of these sites are characterized by dark brown paleosols that are easily distinguishable from the light brown paleosols of the valley. To demonstrate whether these strata are anthropogenic or natural requires a better geochemical understanding of sediment. Soil samples were taken across six different sites; four sites are associated with archaeological findings (sites BF, LP, PB and AC8); another one is from a natural sec…
Influence of antioxidants intercalated layered double hydroxides (AO-LDHs) on the thermo-oxidative stability of pla and pe based nanocomposites
2016
Layered double hydroxides (LDHs) are excellent host matrices for storage and delivery of antioxidants (AOs).