Search results for " layer"
showing 10 items of 1022 documents
Ni/Zn Layered Double Hydroxide (LDH) Micro/Nanosystems and Their Azorubine Adsorption Performance
2021
A membranous shaped Ni/Zn layered double hydroxide based nanohybrid was obtained using a low-cost template-free hydrothermal process at optimized growth conditions of 180 °C for 6 h. The synthesized nanohybrid was structurally, texturally and morphologically characterized using different techniques such as X-ray diffraction, FTIR, XPS spectroscopy, BET analysis and FESEM microscopy. The adsorption performance of our product was estimated through the Azorubine dye removal from synthetic wastewater. We therefore studied the synergic effects of Ni/Zn adsorbent dosage, contact time, pH, adsorbate concentration, stirring speed and temperature on the Azorubine adsorption efficiency. In this inves…
Large Area Deposition by Radio Frequency Sputtering of Gd0.1Ce0.9O1.95 Buffer Layers in Solid Oxide Fuel Cells: Structural, Morphological and Electro…
2021
We investigate the influence of position, under large circular sputtering targets, on the final electrochemical performance of 35 mm diameter button solid oxide fuel cells with sputter-deposited Gadolinium doped Ceria barrier layers, positioned in order to almost cover the entirety of the area associated with a 120 × 80 mm2 industrial cell. We compare the results obtained via structural and morphological analysis to the Electrochemical Impedance Spectroscopy (EIS) measurements performed on the button cells, disentangling the role of different parameters. The Atomic Force Microscopy analysis makes it possible to observe a decrease in the roughness values from the peripheral to the central zo…
Effect of Cu-Zn coated steel fibers on high temperature resistance of reactive powder concrete
2019
Abstract Even though many studies have reported about the impacts of shape, length and distribution of steel fiber reinforcement on global concrete properties, there is a lack of information about the influence of coating type of steel fibers on high temperature resistance of concrete. This paper describes the effect of Cu-Zn coated steel fibers on selected properties of reactive powder concrete (RPC) after exposure to elevated temperatures. The initial corrosion of zinc in Cu-Zn surface layer is found to be already activated by the alkaline environment of the fresh concrete. The RPC samples reinforced with Cu-Zn coated steel fibers are heated to 600 °C and 1000 °C, and the influence of the…
Nitrous oxide fluxes from permafrost regions
2020
This dataset is a synthesis of published nitrous oxide (N2O) fluxes from permafrost-affected soils in Arctic, Antarctic, and Alpine permafrost regions. The data includes mean N2O flux rates measured under field (in situ) conditions and in intact plant-soil systems (mesocosms) under near-field conditions. The dataset further includes explanatory environmental parameters such as meteorological data, soil physical-chemical properties, as well as site and experimental information. Data has been synthesized from published studies (see 'Further details'), and in some cases the authors of published studies have been contacted for additional site-level information. The dataset includes studies publ…
Unexpected vertical structure of the Saharan Air Layer and giant dust particles during AER-D
2018
The Saharan Air Layer (SAL) in the summertime eastern Atlantic is typically well mixed and 3–4 km deep, overlying the marine boundary layer (MBL). In this paper, we show experimental evidence that at times a very different structure can be observed. During the AERosol properties – Dust (AER-D) airborne campaign in August 2015, the typical structure described above was observed most of the time, and was associated with a moderate dust content yielding an aerosol optical depth (AOD) of 0.3–0.4 at 355 nm. In an intense event, however, an unprecedented vertical structure was observed close to the eastern boundary of the basin, displaying an uneven vertical distribution and a very …
L'intonaco Li Vigni nell'architettura del XX secolo a Palermo. Nuove conoscenze e applicazioni diagnostiche per la manutenzione
2013
Il saggio presenta lo studio degli intonaci formulati per imitare le pietre e i marmi naturali che si diffondono in Sicilia all’inizio del XX secolo ed evidenzia che le prime applicazioni e la diffusione delle nuove malte, anche nel resto dell’Italia, risentono delle sperimentazioni condotte in tutta l’Europa. Il contributo riassume i risultati di una rigorosa e capillare ricognizione tra i brevetti conservati presso l’Archivio Centrale dello Stato a Roma inerenti alle malte per il confezionamento dell’intonaco a “finta pietra”, ne analizza i contenuti in modo critico e pone in risalto i contatti culturali con le sperimentazioni dei materiali in atto nell’ambito dei grandi cantieri di resta…
Structural Characterisation of Complex Layered Double Hydroxides and TGA-GC-MS Study on Thermal Response and Carbonate Contamination in Nitrate- and …
2015
Layered double hydroxides (LDHs) are versatile materials used for intercalating bioactive molecules in the fields of pharmaceuticals, nutraceuticals and cosmetics, with the purpose of protecting them from degradation, enhancing their water solubility to increase bioavailability and improving their pharmacokinetic properties and formulation stability. Moreover, LDHs are used in various technological applications to improve stability and processability. The crystal chemistry of hydrotalcite-like compounds was investigated by X-ray powder diffraction (XRPD), automated electron diffraction tomography (ADT) and thermogravimetric analysis (TGA)-GC-MS to shed light on the mechanisms involved in io…
Research data supporting "Antiferromagnetism and p-type conductivity of non-stoichiometric nickel oxide thin films"
2019
Raw data for the manuscript. The dataset contains the files used for the figures and tables in the Article and its Supporting Information. See the Readme file for a detailed description of the dataset.
Nitrogen plasma pressure influence on the composition of TiNxOy sputtered films
2002
Thin films of TiNxOy were deposited by d.c. magnetron sputtering on glass substrates using an (Ar+,N2) plasma and Ti target. The N2 partial pressure was changed from 2.3 × 10−4 mbar to 4.6 × 10−3 mbar in order to obtain films with increasing nitrogen contents. X-ray photoelectron spectroscopy was used to determine the as-deposited composition. The presence of oxygen, which is probably due to contamination from the residual atmosphere in the vacuum chamber, is always detected, both in the surface layers and in the bulk of the films, confirming the formation of TiNxOy. When the nitrogen partial pressure was increased, a maximum for the nitrogen content in the films was reached, corresponding …
Thermally induced structural modifications and O2 trapping in highly porous silica nanoparticles
2014
Abstract In this work we investigate by Raman spectroscopy the effect of isochronal (2 h) thermal treatments in air in the temperature range 200–1000 °C of amorphous silicon dioxide porous nanoparticles with diameters ranging from 5 up to 15 nm and specific surface 590–690 m2/g. Our results indicate that the amorphous structure changes similarly to other porous systems previously investigated, in fact superficial SiOH groups are removed, Si–O–Si linkages are created and the ring statistic is modified, furthermore these data evidence that the three membered rings do not contribute significantly to the Raman signal detected at about 495 cm−1. In addition, after annealing at 900 and 1000 °C we…