Search results for "Spectral"

showing 10 items of 3116 documents

Transition probabilities for some infrared O I spectral lines—Application for determining excitation temperatures in low temperature plasmas

2008

Intensities of selected spectral transitions of neutral oxygen emitted from a wall-stabilized arc have been measured. Applying reliable transition probability data taken from literature, Boltzmann plots have been constructed and the temperatures of the plasma have been obtained. At arc plasma conditions ensuring partial local thermal equilibrium, transition probabilities for 4 O I spectral lines from the near infrared spectral range have been obtained. These new results, together with data for two other studied O I spectral lines taken from the National Institute of Standards and Technology data base, are proposed as a suitable set of transition probabilities applicable for diagnostics of l…

Thermal equilibriumRange (particle radiation)ChemistryInfraredNear-infrared spectroscopyPlasmaAtomic and Molecular Physics and OpticsSpectral lineAnalytical Chemistrysymbols.namesakeBoltzmann constantsymbolsAtomic physicsInstrumentationSpectroscopyExcitationSpectrochimica Acta Part B: Atomic Spectroscopy
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Quantitative interpretation of the red edge excitation (REE) effect of 9,9′-bianthryl in polyisobutene by band shape analysis of the temperature-depe…

1994

Optical fluorescence spectra of 9,9′-bianthryl (BA) in polyisobutene (PIB) were measured as a function of the excitation wavelength at various temperatures between 210 and 293 K. Irradiation at the red edge of the absorption spectra selectively excites distinct conformers with respect to the torsional angle. This leads to a strong dependence of the vibronic band shape of the fluorescence spectra on the excitation wavelength. The marked temperature dependence of the band shape may be attributed to the viscosity-dependent deceleration of the torsional relaxation of BA in the highly viscous polymer which prevents the excited state ensemble from reaching thermal equilibrium. The predominant bro…

Thermal equilibriumSmoluchowski coagulation equationAbsorption spectroscopyChemistryGeneral Chemical EngineeringRelaxation (NMR)Analytical chemistryMolecular physicsSpectral lineFluorescence spectroscopysymbols.namesakeExcited statesymbolsExcitationBerichte der Bunsengesellschaft für physikalische Chemie
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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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(Me3Sn)2SbSb(SnMe3)2, 1∞-verknüpfte SbSb-Hanteln in einem thermochromen Distiban mit Schweratomgerüst

1987

Abstract Single crystals of the thermochromic distibane (Me 3 Sn) 4 Sb 2 ( 1 ) are obtained by irradiation of (Me 3 Sn) 3 Sb with sunlight. The crystal structure of 1 is reported as linear chains of distibane molecules in trans conformation with Sb ⋯ Sb contacts of 389 ppm. Diffuse reflexion spectra of 1 in the solid state and in solution demonstrate thermochromic effect. The Raman spectrum of solid 1 exhibits strong absorption at 162 cm −1 for ν(Sb 2 ).

ThermochromismChemistryStereochemistryOrganic ChemistryCrystal structureBiochemistrySpectral lineInorganic ChemistryCrystallographysymbols.namesakeX-ray crystallographyMaterials ChemistrysymbolsMoleculeIrradiationPhysical and Theoretical ChemistryAbsorption (chemistry)Raman spectroscopyJournal of Organometallic Chemistry
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Synthesis, infrared and121Sb M�ssbauer spectra of some Antimony(III) Thiocyanate Complexes

1989

The first isolation of an antimony(III) thiocyanate complex salt, [(CH3)4N][Sb(CNS)4] (I), and of two adducts of the Sb(CNS)3 formal unit with potentially tridentate nitrogen donors, Sb(CNS)3tpta (II) and [Sb(CNS)3]3(dqp)2 (III), is described. In these derivatives, infrared and Mossbauer spectral data are essentially indicating the predominant presence of N-bonded thiocyanate. For complex I, the occurrence also of groups bridging through the nitrogen atom is advanced. Synthese, IR- und 121Sb-Mosbauer-Spektren von Antimon (III)-thiocyanat-Komplexen Die erstmalige Darstellung eines Antimon(III)-thiocyanat-Komplexes, [(CH3)4N][Sb(CNS)4] (I) und von zwei Addukten der formalen Sb(CNS)3-Einheit m…

ThiocyanateInfraredStereochemistrychemistry.chemical_elementMedicinal chemistryAdductInorganic Chemistrychemistry.chemical_compoundchemistryAntimonyNitrogen atomMössbauer spectroscopyMossbauer spectraSpectral dataZeitschrift f�r anorganische und allgemeine Chemie
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Validation of the solution method using Tikhonov regularization algorithm for spectral line diagnostics of microsize plasma

2014

This paper is devoted obtaining the threshold of the credibility of the solution by means of Tikhonov's regularization method in case of spectral lines, emitted from microsize plasma sources. The reliability of Tikhonov algorithm was verified by means of solving model tasks with different ratio between instrumental function and measured profile and, with different levels of noise.

Tikhonov regularizationInstrumental functionPlasmaRegularization (mathematics)AlgorithmSpectral lineMathematicsSPIE Proceedings
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New Regularization Method for EXAFS Analysis

2007

As an alternative to the analysis of EXAFS spectra by conventional shell fitting, the Tikhonov regularization method has been proposed. An improved algorithm that utilizes a priori information about the sample has been developed and applied to the analysis of U L3‐edge spectra of soddyite, (UO2)2SiO4⋅2H2O, and of U(VI) sorbed onto kaolinite. The partial radial distribution functions g1(UU), g2(USi), and g3(UO) of soddyite agree with crystallographic values and previous EXAFS results.

Tikhonov regularizationX-ray spectroscopyExtended X-ray absorption fine structureAbsorption spectroscopyChemistryRegularization (physics)Analytical chemistryCrystal structureSpectroscopySpectral lineAIP Conference Proceedings
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Deconvolution of Multiple Spectral Lines Shapes by Means of Tikhonov’s Regularization Method

2013

We present deconvolution of multiple narrow Zeeman split Hg lines, emitted from Hg/Xe micro-size capillary and measured by the Fourier Transform spectrometer. The ill-posed inverse problem was solved using the Tikhonov& rsquo;s regularization method.

Tikhonov regularizationsymbols.namesakeZeeman effectFourier transform spectrometersAnalytical chemistrysymbolsDeconvolutionInverse problemRegularization (mathematics)Spectral lineMathematicsMagnetic fieldComputational physicsImaging and Applied Optics
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Quaternary structure dependence of kinetic hole burning and conformational substates interconversion in hemoglobin.

2003

Using a sol-gel encapsulation technique, we have prepared samples of CO saturated human adult hemoglobin locked in the R or T quaternary conformation. We report time-resolved spectra of these samples in the Soret region following flash photolysis, in the time interval ranging from 250 ns to 200 ms and in the temperature interval of 100-170 K. A suitable analysis of the measured difference spectra enables us to obtain the spectral contribution of deoxyHb and HbCO molecules as a function of time and/or of the fraction N(t) of deoxyHb molecules. In our experimental time window geminate CO rebinding to hemoglobin in the T quaternary conformation is about 2 orders of magnitude slower than to hem…

Time FactorsChemistryAnalytical chemistryEnergy landscapeflash photolysiKinetic energyLigandsBiochemistrySpectral lineCrystallographyHemoglobinsprotein dynamicTime windowsMoleculeFlash photolysisHumanstime-resolved absorption spectroscopyProtein quaternary structureHemoglobinProtein Structure QuaternaryProtein BindingBiochemistry
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