Search results for " Spectra"
showing 10 items of 709 documents
Emissivity errors in the vegetation cover method caused by the lack of atmospheric correction
2008
The influence of the lack of atmospheric correction of the optical images used to calculate land surface emissivity (LSE) was assessed. When thermal emissivity is determined by the vegetation cover method (VCM), information from the solar spectrum is required to calculate the vegetation cover fraction. The atmospheric correction was obtained in this study by using a combination of the dark dense vegetation (DDV) method and the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) code. The methodology was applied to a Landsat Thematic Mapper (TM) image of Tomelloso, Spain. We determined that the emissivity between 10 and 12 µm only increases by 0.4% (which represents a system…
Evidence for thermal equilibration in multifragmentation reactions probed with bremsstrahlung photons
2001
The production of nuclear bremsstrahlung photons (E$_{\gamma}>$ 30 MeV) has been studied in inclusive and exclusive measurements in four heavy-ion reactions at 60{\it A} MeV. The measured photon spectra, angular distributions and multiplicities indicate that a significant part of the hard-photons are emitted in secondary nucleon-nucleon collisions from a thermally equilibrated system. The observation of the thermal component in multi-fragment $^{36}$Ar+$^{197}$Au reactions suggests that the breakup of the thermalized source produced in this system occurs on a rather long time-scale.
Estimates for Sums of Eigenvalues of the Free Plate via the Fourier Transform
2017
Using the Fourier transform, we obtain upper bounds for sums of eigenvalues of the free plate.
Analysis of spectral line shapes in low-temperature plasma by means of inverse ill-posed problem solution
2017
Promocijas darbs ir veltīts zemtemperatūras plazmas diagnostikas metodes attīstīšanai, augstfrekvences bezelektrodu lampām (ABL). Darbā tika izstrādāta jauna metode spektroskopisko datu apstrādei un reālo spektrāllīniju kontūru noteikšanai, risinot nekorekto apgriezto uzdevumu, kas balstās uz Tihonova regularizācijas algoritmu. Metode tika testēta aprēķinot patiesās profilu formas izmantojot eksperimentāli iegūtas Hg līnijās, emitētas no specialas formas mikro ABL. Tika pierādīts, ka aparatūras funkcijas neņemšana vērā zemtemperatūras plazmas gadījumā var ieviest lielu neprecizitāti, nosakot profilu formu un platumu un, sekojoši, ABL temperatūru. Tika analizēta arī atkarība no bufergāzes ve…
Social network analysis: the use of graph distances to compare artificial and criminal networks
2021
Aim: Italian criminal groups become more and more dangerous spreading their activities into new sectors. A criminal group is made up of networks of hundreds of family gangs which extended their influence across the world, raking in billions from drug trafficking, extortion and money laundering. We focus in particular on the analysis of the social structure of two Sicilian crime families and we used a Social Network Analysis approach to study the social phenomena. Starting from a real criminal network extracted from meetings emerging from the police physical surveillance during 2000s, we here aim to create artificial models that present similar properties. Methods: We use specific tools of s…
Comparative study of historical woods from XIX century by thermogravimetry coupled with FTIR spectroscopy
2019
Thermal and structural properties of historical woods from apparatuses of the Historical Collection of the Physics Instruments of the University of Palermo have been investigated by FTIR spectroscopy coupled with thermogravimetric analysis. Specifically, the wooden portions of apparatuses from XIX century have been studied. The investigated woods belong to different taxa (Swietenia mahagoni, Picea abies and Juglans regia). The thermal behavior of the wooden materials has been successfully interpreted on the basis of specific indexes determined by the quantitative analysis of the FTIR spectra. The kinetics of the wood pyrolysis have been investigated by using a non-isothermal approach based …
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…
Classification of Pecorino cheeses produced in Italy according to their ripening time and manufacturing technique using Fourier transform infrared sp…
2010
Fourier-transform infrared spectroscopy, followed by linear discriminant analysis of the spectral data, was used to classify Italian Pecorino cheeses according to their ripening time and manufacturing technique. The Fourier transform infrared spectra of the cheeses were divided into 18 regions and the normalized absorbance peak areas within these regions were used as predictors. Linear discriminant analysis models were constructed to classify Pecorino cheeses according to different ripening stages (hard and semi-hard) or according to their manufacturing technique (fossa and nonfossa cheeses). An excellent resolution was achieved according to both ripening time and manufacturing technique. A…
Do fluorescence and transient absorption probe the same intramolecular charge transfer state of 4-(dimethylamino)benzonitrile?
2009
International audience; We present here the results of time-resolved absorption and emission experiments for 4-(dimethylamino)benzonitrile in solution, which suggest that the fluorescent intramolecular charge transfer (ICT) state may differ from the twisted ICT (TICT) state observed in transient absorption.
The Tortricidae described by J. C. Fabricius (Lepidoptera)
2011
The identity and nomenclature of the 88 species of Tortricidae (Lepidoptera) described by J. C. Fabricius are reviewed. Type material deposited in the Natural History Museum Denmark is illustrated. Lectotypes for Tinea compositella (Fabricius, 1775), Pyralis rivellana (Fabricius, 1775) and P. strigana (Fabricius, 1775) are designated. Two new synonymies are proposed: Pyralis marmorana (Fabricius, 1798), syn. n., of Ancylis achatana (Denis and Schiffermuller, 1775), and P. rusticana (Fabricius, 1794), syn. n., of Epinotia solandriana (Linnaeus, 1758). In an appendix, the identity and nomenclature of the 49 species of non-Tortricidae described by Fabricius in the genus Pyralis Linnaeus, 1758 …