Search results for " Spectra"

showing 10 items of 709 documents

Evaluation of Skin Vascular Malformations’ Laser Treatment by RGB and Multi-spectral Imaging

2012

RGB imaging system for mapping and monitoring of hemoglobin changes in skin has been tested for evaluation of vascular malformations’ laser treatment. The multi-spectral imaging system was used as the reference.

Pathologymedicine.medical_specialtymedicine.diagnostic_testDiffuse reflectance infrared fourier transformbusiness.industryLaser treatmentMultispectral imageMulti spectralSpectral imagingOptical coherence tomographymedicineRGB color modelsense organsbusinessBiomedical engineeringBiomedical Optics and 3-D Imaging
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Measurement of jet suppression in central Pb–Pb collisions at √sNN = 2.76 TeV

2015

The transverse momentum (pT) spectrum and nuclear modification factor (RAA) of reconstructed jets in 0–10% and 10–30% central Pb–Pb collisions at √sNN = 2.76 TeV were measured. Jets were reconstructed using the anti-kT jet algorithm with a resolution parameter of R = 0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pT spectra are reported in the pseudorapidity interval of |ηjet| 5 GeV/c to suppress jets constructed from the combinatorial background in Pb–Pb collisions. The leading charged particle requirement applied to jet spectra both in pp and Pb– Pb collisions had a negligible effect on the RAA. The nuclear m…

Pb–Pb collisionsAstrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::Experimentjet suppressionjet spectraNuclear Experiment
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Development of Peat Processing Methods for Production of Innovative Products

2020

Synthesis or humification of humic substances (HSs) is the second widely applied organic compound transformation process after photosynthesis. Peat decomposition process results in a production of a HSs which has a high demand in agriculture, forestry, and gardening areas. Addition of the KOH is good option for environmental protection and K+ belongs to the nitrogen, potassium and phosphorous (NKP) mineral component. A homogenization process in a customize for commerce, where peat treatment technology was improved with the help of the cavitation effect. This effect was provided with the help of the high-speed mixer-disperser (HSMD) developed at Riga Technical University. Mechanical cavitati…

PeatChemistry020209 energyMechanical EngineeringFulvic acid02 engineering and technology021001 nanoscience & nanotechnologyPulp and paper industryFluorescence spectraProcessing methodsMechanics of Materials0202 electrical engineering electronic engineering information engineeringProduction (economics)General Materials Science0210 nano-technologyKey Engineering Materials
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Interactions of benzodiazepines with human serum albumin. Circular dichroism studies.

1973

The circular dichroism spectra of 12 benzodiazepine derivatives studied in presence of human serum albumin are presented. Nearly all substances give biphasic extrinsic Cotton effects. At the CD maxima the molar ellipticities and the anisotropy factors are calculated. The influence of the chemical structure of the benzodiazepines on the induced Cotton effect is discussed. There is a linear correlation between the anisotropy factors and the logarithms of the partition coefficients of the substances. It is suggested that the phenyl ring of the benzodiazepine molecule is one of the essential groups for the binding of these substances to human serum albumin.

PharmacologyBenzodiazepineCircular dichroismChromatographyBinding SitesChemistrymedicine.drug_classChemical structureCircular DichroismGeneral MedicineBenzazepinesHuman serum albuminCircular dichroism spectraPartition coefficientStructure-Activity RelationshipOptical Rotatory DispersionmedicineMoleculeHumansSpectrophotometry UltravioletChlorineCotton effectSerum Albuminmedicine.drugProtein BindingNaunyn-Schmiedeberg's archives of pharmacology
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Active locking and entanglement in type II optical parametric oscillators

2018

Type II optical parametric oscillators are amongst the highest-quality sources of quantum-correlated light. In particular, when pumped above threshold, such devices generate a pair of bright orthogonally-polarized beams with strong continuous-variable entanglement. However, these sources are of limited practical use, because the entangled beams emerge with different frequencies and a diffusing phase-difference. It has been proven that the use of an internal wave-plate coupling the modes with orthogonal polarization is capable of locking the frequencies of the emerging beams to half the pump frequency, as well as reducing the phase-difference diffusion, at the expense of reducing the entangl…

Phase differencePhysicsQuantum PhysicsOrthogonal polarization spectral imagingbusiness.industryFOS: Physical sciencesGeneral Physics and AstronomyQuantum entanglementParameter spaceLaserPolarization (waves)01 natural sciencesÒptica quàntica010305 fluids & plasmaslaw.inventionOpticslaw0103 physical sciencesddc:530Well-definedQuantum Physics (quant-ph)010306 general physicsbusinessParametric statistics
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Crystal structure transformations induced by surface stresses in BaTiO3and BaTiO3@SiO2nanoparticles and ceramics

2015

International audience; Lattice structure transformations in nanopowders of ferroelectric BaTiO3 and BaTiO3@SiO2 core-shell nanostructured ceramics were studied by nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) at the temperatures 120–450 K and particle size of 300 and 500 nm. NMR spectra of all studied samples in the paraelectric phase are identical to the spectra in bulk material indicating their perfect perovskite structure without visible influence of particle surface. However, we have found that surface of particles essentially influence the ferroelectric phase transitions detected by both NMR and EPR techniques. The strongest changes as compared to bulk mat…

Phase transitionMaterials scienceAnalytical chemistry02 engineering and technologyCrystal structureceramics01 natural scienceslaw.inventionCondensed Matter::Materials Sciencechemistry.chemical_compoundNuclear magnetic resonancelawPhase (matter)barium titanate0103 physical sciencesGeneral Materials Science010306 general physicsElectron paramagnetic resonanceInstrumentation[CHIM.MATE]Chemical Sciences/Material chemistry021001 nanoscience & nanotechnologyFerroelectricityNMR spectra databasenuclear magnetic resonanceferroelectric phase transitionchemistryBarium titanateCurie temperaturenanoparticlesCondensed Matter::Strongly Correlated Electrons0210 nano-technologyPhase Transitions
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A combined theoretical and experimental determination of the electronic spectrum of acetone

1996

A combined ab initio and experimental investigation has been performed of the main features of the electronic spectrum of acetone. Vertical transition energies have been calculated from the ground to the ny→π∗, π→π∗, σ→π∗, and the n=3 Rydberg states. In addition, the 1A1 energy surfaces have been studied as functions of the CO bond length. The 1A1 3p and 3d states were found to be heavily perturbed by the π→π∗ state. Resonant multiphoton ionization and polarization‐selected photoacoustic spectra of acetone have been measured and observed transitions were assigned on internal criteria. The calculated vertical transition energies to the ny→π∗ and all Rydberg states were found to be in agreeme…

Photoacoustic SpectroscopyOvertoneAb initioGeneral Physics and AstronomyPhotoionizationPhotoionizationSpectral lineAcetoneBond LengthsGround Statessymbols.namesakeRydberg StatesAb initio quantum chemistry methodsPolarizationIonizationPhysics::Atomic PhysicsPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]Carbon MonoxideEnergyChemistryUNESCO::FÍSICA::Química físicaSurfacesBond lengthElectron SpectraRydberg formulasymbolsAb Initio Calculations ; Acetone ; Bond Lengths ; Carbon Monoxide ; Electron Spectra ; Energy ; Ground States ; Multi−Photon Processes ; Photoacoustic Spectroscopy ; Photoionization ; Polarization ; Rydberg States ; SurfacesMulti−Photon ProcessesAtomic physicsAb Initio CalculationsThe Journal of Chemical Physics
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Ab initio study on the low-lying excited states of retinal

1997

Ab initio results for the electronic spectrum of all-trans-retinal and its truncated model 3-methyl-all-trans (10-s-cis)-2,4,6,8,10-undecapentaen-1-al are presented. The study includes geometry determination of the ground state. Vertical excitation energies have been computed using multiconfigurational second-order perturbation theory through the CASPT2 formalism. The lowest singlet excited state in gas phase is predicted to be of nπ∗ character. The lowest triplet state corresponds, however, to a ππ∗ state. The most intense feature of the spectrum is due to the strongly dipole-allowed ππ∗ transition, in accordance with the observed maximum in the one-photon spectra. The vertical excitation …

PhotochemistryChemistryExcited statesAb initioGeneral Physics and AstronomyPerturbation theoryTriplet stateSpectral lineGround statesUNESCO::FÍSICA::Química físicaAb initio quantum chemistry methodsExcited stateOrganic compoundsSolvent effectsTwo-photon spectraIsomerisationAb initio calculationsSinglet statePhysical and Theoretical ChemistryAtomic physicsTriplet state:FÍSICA::Química física [UNESCO]Ground stateExcitationOrganic compounds ; Excited states ; Ab initio calculations ; Perturbation theory ; Triplet state ; Solvent effects ; Isomerisation ; Ground states ; Two-photon spectra ; Photochemistry
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Observing heme doming in myoglobin with femtosecond X-ray absorption spectroscopy.

2015

International audience; We report time-resolved X-ray absorption measurements after photolysis of carbonmonoxy myoglobin performed at the LCLS X-ray free electron laser with nearly 100 fs (FWHM) time resolution. Data at the Fe K-edge reveal that the photoinduced structural changes at the heme occur in two steps, with a faster (∼70 fs) relaxation preceding a slower (∼400 fs) one. We tentatively attribute the first relaxation to a structural rearrangement induced by photolysis involving essentially only the heme chromophore and the second relaxation to a residual Fe motion out of the heme plane that is coupled to the displacement of myoglobin F-helix

PhotodissociationAbsorption spectroscopyTime resolved spectroscopyInvited ArticlesPhotochemistrySPECIAL TOPIC: BIOLOGY WITH X-RAY LASERS 2chemistry.chemical_compoundX-ray absorption spectralcsh:QD901-999X-ray absorption near edge structureSpectroscopyInstrumentationHemeSpectroscopy[PHYS]Physics [physics]RadiationX-ray optics[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry Molecular Biology/Structural Biology [q-bio.BM]ChemistryPhotodissociationRelaxation (NMR)ChromophoreCondensed Matter PhysicsSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)MyoglobinBiofisica Dinamica delle proteine Spettroscopia risolta in tempo X-ray free-electron laser Assorbimento di raggi Xlcsh:CrystallographyTime-resolved spectroscopyStructural dynamics (Melville, N.Y.)
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A critical assessment of automatic photoelastic methods for the analysis of edge residual stresses in glass

2014

The measurement of residual stresses is of great importance in the glass industry. The analysis of residual stresses in the glass is usually carried out by photoelastic methods since the glass is a photoelastic material. This article considers the determination of membrane residual stresses of glass plates by digital photoelasticity. In particular, it presents a critical assessment concerning the automated methods based on gray-field polariscope, spectral content analysis, phase shifting, RGB photoelasticity, “test fringes” methods and “tint plate” method. These methods can effectively automate manual methods currently specified in some standards.

PhotoelasticityMaterials scienceGlass industrybusiness.industryApplied MathematicsMechanical EngineeringMechanical engineeringEdge (geometry)OpticsMechanics of MaterialsResidual stressModeling and SimulationCritical assessmentGlass residual stress digital photoelasticity gray-field polariscope spectral content analysis phase shifting RGB photoelasticity test fringes image processingbusinessThe Journal of Strain Analysis for Engineering Design
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