Search results for " surface"

showing 10 items of 2838 documents

Rapid and eco-friendly synthesis of graphene oxide-silica nanohybrids

2014

The increasing interest in Graphene oxide (GO) is due to many issues: the presence of both sp2-conjugated atoms and oxygen-containing functional groups provides a strong hydrophilicity and the possibility to further functionalize it with other molecules (i.e. π-π interactions covalent attachment etc.) [1]. Furthermore since the GO is biocompatible and noncytotoxic many studies have been recently focused on the development of GO-based nanodevices for bioimaging DNA detection drug delivery. Due to their low cytotoxicity and large internal surface area silica nanoparticles have been taken into account as promising material for biolabeling and drug loading/delivery. Particular consideration has recently been demonstrated for GO-silica composites because of the potentialities for electrical applications their chemical inertia and stability toward ions exposure. The possibility to combine the extraordinary properties of GO and silica offers several advantages for the realization of nanoprobes for biological applications and of biosensor [12]. The strategy for the fabrication of GO-nanosilica nanohybrids can be schematized as follows: (i) synthesis of GO by oxidizing graphite powder with the method described by Marcano et al. [3] (ii) Preparation of oxygen-loaded silica nanoparticles by thermal treatments in controlled atmosphere in order to induce high NIR emission at 1272 nm from high purity silica nanoparticles. (iii) preparation of GrO-silica nanohybrid films via rapid solvent casting in water. The nanohybrids were tested by XPS FTIR Raman analysis UV photoluminescence analysis TGA Zeta potential measurements electrical tests AFM and SEM. Several nanohybrids were prepared by combining two different typologies of GO and two different samples of silica.
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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…

The paper presents the study of the plaster formulated to imitate the natural stones and marbles that are popular in Sicily in the early twentieth century and points out that the first applications and the dissemination of new mortars also in the rest of Italy feels the influence of the experiments conducted throughout Europe . The contribution summarizes the results of a rigorous and thorough reconnaissance of patents kept in the Archivio Centrale dello Stato in Rome relating to mortars for plastering an artificial stone critically analyzes the content and emphasizes cultural contacts with the experiments on large-scale restoration projects in Italy and France in the late nineteenth century. The analysis of the architectural surfaces is developed with instrumental tests: the levels of adhesion of finishing surface are characterized in particular through a campaign of thermographic investigations and diagnosis is drawn to show that the consolidation of the layers and reintegration are interventions to be introduced ​​within the restoration project and maintenance program.Settore ICAR/19 - Restauro
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Surface plasmon interference fringes in back-reflection

2010

We report the experimental observation of surface plasmon polariton (SPP) interference fringes with near-unity visibility and half-wavelength periodicity obtained in back reflection on a Bragg mirror. The presented method based on leakage radiation microscopy (LRM) represents an alternative solution to optical near-field analysis and opens new ways for the quantitative analysis of SPP fringes. With LRM we investigate various SPP interference patterns and analyze the high reflectivity of Bragg mirror in comparison with theoretical models.

Theoretical modelsFOS: Physical sciencesGeneral Physics and AstronomyPhysics::Optics02 engineering and technology01 natural sciencesOpticsInterference (communication)0103 physical sciencesMicroscopy010306 general physicsPhysicsCondensed Matter::Quantum Gases[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]business.industrySurface plasmon021001 nanoscience & nanotechnologyDistributed Bragg reflectorSurface plasmon polariton[ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]Reflection (physics)Optoelectronics0210 nano-technologybusinessPhysics - OpticsOptics (physics.optics)Localized surface plasmon
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Biomass-based composite catalysts for catalytic wet peroxide oxidation of bisphenol A : preparation and characterization studies

2019

Abstract The wet granulation process was used to prepare new, efficient, and cost-effective granular biomass-based composite catalysts for catalytic wet peroxide oxidation (CWPO) of bisphenol A (BPA). The most stable composite granules was prepared by mixing biomass-based carbon residue (CR) with metakaolin (MK) combined with calcium oxide (CaO) or cement and a solvent (NaOH or KOH). For all the prepared composite granules, the optimized binding agents to carbon ratio was 0.3, the solvent to carbon ratio 1.2, and the agitation rate 1200 rpm. The specific surface area of the prepared catalysts was 152–205 m2/g. The composite granular catalyst (CR + MK + CaO + NaOH) had the most durable and s…

Thermal desorption spectroscopybiomassacomposite catalystComposite numbergranular activated carbon02 engineering and technologyjätevesi010501 environmental sciences01 natural sciencesPeroxidewastewater purificationCatalysisGranulationchemistry.chemical_compoundSpecific surface areaChemical Engineering (miscellaneous)Calcium oxideWaste Management and Disposalta116komposiitit0105 earth and related environmental sciencesjäteveden käsittelybiomassProcess Chemistry and Technology021001 nanoscience & nanotechnologyPollutionSolventchemistryaktiivihiilioxidation of bisphenol A0210 nano-technologyNuclear chemistryJournal of Environmental Chemical Engineering
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Structure relaxation after temperature jumps in homogeneous polystyrene/poly(styrene-co-bromostyrene) blends

1988

Concentration fluctuations in polymer blends and their change after a temperature jump were studied by time-dependent small angle X-ray scattering experiments. Measurements were conducted on homogeneous mixtures of polystyrene and a partially brominated derivative. Structure factors in thermal equilibrium show the form given by the random phase approximation, thus enabling a direct determination of theχ-parameter and the mean radius of gyration. TheT-dependence ofχ can be understood as the result of superposed enthalpic contributions and a free volume term. In theT-jump experiments, samples were quenched to temperatures near Tg. Relaxation occurs on the time scale of minutes and is nonexpon…

Thermal equilibriumMaterials sciencePolymers and PlasticsScatteringThermodynamicsStyrenechemistry.chemical_compoundColloid and Surface ChemistrychemistryTemperature jumpPolymer chemistryMaterials ChemistryRadius of gyrationRelaxation (physics)PolystyrenePhysical and Theoretical ChemistryStructure factorColloid & Polymer Science
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Review of thermal infrared applications and requirements for future high-resolution sensors

2016

High-resolution thermal infrared (TIR) remote sensing has a wide range of applications. In this paper, we describe the different applications and requirements identified in a literature review and during a consultation meeting with researcher experts in different fields. As a result, more than 30 applications were identified within three different fields: 1) land and solid Earth; 2) health and hazards; and 3) security and surveillance. A complete set of requirements (spatial, temporal, and radiometric resolution, algorithms used, and supporting data, among others) for each application is also provided. The results presented in this paper provide useful information to enhance the importance …

Thermal infrared010504 meteorology & atmospheric sciencesComputer scienceFuegosathigh resolution0211 other engineering and technologiesHigh resolutionland surface temperatureSettore ING-INF/02 - Campi Elettromagnetici02 engineering and technology01 natural sciencesSet (abstract data type)Fuegosat; high resolution; land surface emissivity; land surface temperature; thermal infraredland surface emissivitySystems engineeringGeneral Earth and Planetary Sciencesthermal infraredElectrical and Electronic EngineeringSolid earth021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensing
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Minimum configuration of thermal infrared bands for land surface temperature and emissivity estimation in the context of potential future missions

2014

Abstract A number of applications rely on the availability of high resolution TIR data, both in terms of spatial and temporal resolution, as well as in terms of spectral configuration. A consensus exists among the thermal community regarding the lack of such a kind of data, since only one operational sensor is currently providing multispectral TIR data at high spatial resolution (the case of ASTER, at 90 m spatial resolution and a 16-day revisit time). In this paper we propose a minimum multispectral configuration to allow the retrieval of both land surface temperature (LST) and emissivity ( e ) from thermal infra-red (TIR) data. For this purpose, we propose a minimum configuration based on…

Thermal infraredLand surface temperatureComputer scienceTemporal resolutionMultispectral imageThermalEmissivityHigh spatial resolutionSoil ScienceGeologyComputers in Earth SciencesImage resolutionRemote sensingRemote Sensing of Environment
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Land Surface Temperature Retrieval Methods From Landsat-8 Thermal Infrared Sensor Data

2014

The importance of land surface temperature (LST) retrieved from high to medium spatial resolution remote sensing data for many environmental studies, particularly the applications related to water resources management over agricultural sites, was a key factor for the final decision of including a thermal infrared (TIR) instrument on board the Landsat Data Continuity Mission or Landsat-8. This new TIR sensor (TIRS) includes two TIR bands in the atmospheric window between 10 and 12 $\mu\hbox{m}$ , thus allowing the application of split-window (SW) algorithms in addition to single-channel (SC) algorithms or direct inversions of the radiative transfer equation used in previous sensors on board …

Thermal infraredLand surface temperatureMeteorologyInfrared windowRadiative transferEmissivityEnvironmental scienceAtmospheric modelElectrical and Electronic EngineeringGeotechnical Engineering and Engineering GeologyImage resolutionSpectral lineRemote sensingIEEE Geoscience and Remote Sensing Letters
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Evaluation of Landsat-8 TIRS data recalibrations and land surface temperature split-window algorithms over a homogeneous crop area with different phe…

2021

Abstract Successive re-calibrations were implemented in Landsat-8 TIRS data since launch. This paper evaluates the performances of both: (1) these re-calibrations, up to the last calibration update announced for TIRS data in the next Landsat Collection 2; and (2) single-channel (SC) corrections and split-window (SW) algorithms to retrieve land surface temperature (LST) from TIRS data. A robust and accurate multi-year (2014–2019) set of reference ground data were used, which included thermal infrared (TIR) radiance measurements taken along transects in a uniform and thermally homogeneous rice paddy area, but also emissivity measurements for the different ground covers at the site through the…

Thermal infraredLand surface temperaturePhenologyAtomic and Molecular Physics and OpticsComputer Science ApplicationsHomogeneousCalibrationRadianceEmissivityEnvironmental scienceComputers in Earth SciencesTransectEngineering (miscellaneous)AlgorithmISPRS Journal of Photogrammetry and Remote Sensing
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Land surface temperature retrieval from LANDSAT TM 5

2004

In this paper, three methods to retrieve the land surface temperature (LST) from thermal infrared data supplied by band 6 of the Thematic Mapper (TM) sensor onboard the Landsat 5 satellite are compared. The first of them lies on the estimation of the land surface temperature from the radiative transfer equation using in situ radiosounding data. The others two are the mono-window algorithm developed by Qin et al. [International Journal of Remote Sensing 22 (2001) 3719] and the single-channel algorithm developed by Jime´nez-Mun˜oz and Sobrino [Journal of Geophysical Research 108 (2003)]. The land surface emissivity (LSE) values needed in order to apply these methods have been estimated from a…

Thermal infraredLans surface emissivityLand surface temperatureNear-infrared spectroscopyOtras Ciencias de la Tierra y relacionadas con el Medio AmbienteSoil ScienceGeologyLandsat 5Ciencias de la Tierra y relacionadas con el Medio AmbienteThematic MapperRadiative transferEmissivityEnvironmental scienceSatelliteComputers in Earth SciencesRoot-mean-square deviationLand Surface TemperatureCIENCIAS NATURALES Y EXACTASRemote sensing
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