Search results for "threshold [energy]"

showing 10 items of 31 documents

Investigation of photoluminescence and amplified spontaneous emission properties of cyanoacetic acid derivative (KTB) in PVK amorphous thin films

2018

This work was supported by European Regional Development Fund within the Project No. 1.1.1.1/16/A/046 and A.Riekstins SIA “Mikrotīkls” donation, administered by University of Latvia Foundation.

guest-host systemAmplified spontaneous emissionQuenching (fluorescence)Materials sciencePhotoluminescenceDye lasercyanoacetic acid derivativeQuantum yieldglass forming low molecular weight compounds02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistryThreshold energy7. Clean energy01 natural sciences0104 chemical sciencesAmorphous solidamplified spontaneous emission:NATURAL SCIENCES:Physics [Research Subject Categories]0210 nano-technologyLuminescencelaser dyesOrganic Electronics and Photonics: Fundamentals and Devices
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The interplay between cooperativity and diversity in model threshold ensembles

2014

The interplay between cooperativity and diversity is crucial for biological ensembles because single molecule experiments show a significant degree of heterogeneity and also for artificial nanostructures because of the high individual variability characteristic of nanoscale units. We study the cross-effects between cooperativity and diversity in model threshold ensembles composed of individually different units that show a cooperative behaviour. The units are modelled as statistical distributions of parameters (the individual threshold potentials here) characterized by central and width distribution values. The simulations show that the interplay between cooperativity and diversity results …

genetic structuresChemistrySystems biologySystems BiologyCell MembraneBiomedical EngineeringBiophysicsElectric ConductivityNanotechnologyCooperativityBioengineeringModels TheoreticalBiochemistryNanostructuresBiomaterialsProbability distributionComputer SimulationThreshold responseBiological systemResearch ArticlesBiotechnologyDiversity (business)
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Stimulated emission and optical properties of pyranyliden fragment containing compounds in PVK matrix

2017

This work has been supported by National Research program “Multifunctional materials and composites, photonics and nanotechnology (IMIS2)”. Financial support provided by Scientific Research Project for Students and Young Researchers No. SJZ2015/12 realised at the Institute of Solid State Physics, University of Latvia is greatly acknowledged.

Amplified spontaneous emissionPhotoluminescenceMaterials scienceQuantum yieldElectron donor02 engineering and technologyPhotochemistry01 natural sciences010309 opticschemistry.chemical_compound0103 physical sciences:NATURAL SCIENCES:Physics [Research Subject Categories]Stimulated emissionElectrical and Electronic EngineeringAmplified spontaneous emissionGlass forming low molecular weight compoundsDCMLaser dyeDye laser021001 nanoscience & nanotechnologyThreshold energyAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialschemistryPyranyliden derivatives0210 nano-technologyMethyl group
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The Z(3985) as a threshold effect from the D¯s⁎D+D¯sD⁎ interaction

2021

Abstract We study the e + e − → K + ( D s ⁎ − D 0 + D s − D ⁎ 0 ) reaction recently measured at BESIII, from where a new Z c s state has been reported. We study the interaction of D ¯ s D ⁎ with the coupled channels J / ψ K − , K ⁎ − η c , D s − D ⁎ 0 , D s ⁎ − D 0 by means of an extension to the charm sector of the local hidden gauge approach. We find that the D s − D ⁎ 0 + D s ⁎ − D 0 combination couples to J / ψ K − and K ⁎ − η c , but the D s − D ⁎ 0 − D s ⁎ − D 0 combination does not. The coupled channels help to build up strength in the D s − D ⁎ 0 + D s ⁎ − D 0 diagonal scattering matrix close to threshold and, although the interaction is not strong enough to produce a bound state or…

PhysicsNuclear and High Energy Physics010308 nuclear & particles physicsThreshold effect0103 physical sciencesBound stateAnalytical chemistryResonance010306 general physics01 natural sciencesPhysics Letters B
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Solid state solvation effect and reduced amplified spontaneous emission threshold value of glass forming DCM derivative in PMMA films

2015

Abstract Molecule crystallization is one of the limitations for obtaining high-gain organic laser systems. One of the examples is well known red laser dye 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM). The lowest threshold value of amplified spontaneous emission was achieved by doping 2 wt% of DCM molecule in tris-(8-hydroxy quinoline) aluminum (Alq3) matrix. Further increase of the DCM dye concentration makes the system less efficient as its threshold value increases. It is due to large intermolecular interaction, which induces photoluminescence quenching. Compounds with reduced intermolecular interaction could be prospective in organic laser systems due to higher …

chemistry.chemical_classificationAmplified spontaneous emissionPhotoluminescenceDye laserOrganic laserMaterials scienceIntermolecular forceBiophysicsAnalytical chemistrySolvationGeneral ChemistryPolymerCondensed Matter PhysicsThreshold energyPhotochemistryBiochemistryAtomic and Molecular Physics and OpticschemistryJournal of Luminescence
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Limits of the linear viscoelastic behaviour of polyamide 66 filled with TiO2 nanoparticles: Effect of strain rate, temperature, and moisture

2008

Abstract Limits of linear viscoelastic behaviour of TiO 2 nanoparticle-filled polyamides are estimated quantitatively by the results of uniaxial tension tests. The stress limit of the filled polymer is higher than that of the un-filled one. Their values are the lower, the higher the temperature and moisture content of test specimens, and the lower, the lower the strain rate. The concept of an energy threshold for the linear viscoelastic behaviour is used to comprehensively characterize the limits over a wide range of test conditions. The energy limit is not affected by the strain rate, temperature, or moisture, and its value for the filled polymer is higher than that for the un-filled one. …

chemistry.chemical_classificationMaterials sciencePolymer nanocompositeMoistureMechanical EngineeringPolymerStrain rateCondensed Matter PhysicsThreshold energyViscoelasticitychemistryMechanics of MaterialsGeneral Materials ScienceComposite materialWater contentTensile testingMaterials Science and Engineering: A
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‘Threshold effect’ of increasing tocopherol ingestion upon the microsomal epoxide hydrolase activity of rat liver

1990

Epoxide HydrolasesMaleChemistryHealth Toxicology and MutagenesisPublic Health Environmental and Occupational HealthAdministration OralRats Inbred StrainsGeneral ChemistryToxicologyRatsMicrosomal epoxide hydrolase activityBiochemistryChemistry (miscellaneous)Rat liverThreshold effectMicrosomes LiverAnimalsVitamin EIngestionTocopherolChromatography High Pressure LiquidFood ScienceFood Additives and Contaminants
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Energy structure of thin films of carbazole derivatives with metal electrodes

2011

Study of charge carrier transport in organic electroluminescent devices, organic photovoltaic devices, and organic field-effect transistors is one of the most important points. In order to realize comparable electron and hole transport in thin organic films with electrodes the energy structure of such devices are of great importance. In this work, we have studied electrical properties and energy structure of two carbazole derivatives. The threshold energy of photoconductivity quantum efficiency is 2.90 eV and optical energy gap is 3.3 eV in thin films is obtained. The values of work function of ITO, Au, Cu and Pd electrodes are energetically close to conductivity level of holes and holes in…

Materials sciencebusiness.industryCarbazolePhotoconductivityElectroluminescenceThreshold energychemistry.chemical_compoundchemistryOptoelectronicsWork functionQuantum efficiencyCharge carrierThin filmbusinessIOP Conference Series: Materials Science and Engineering
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Ab initio calculation of Li7 photodisintegration

2004

The Li7 total photoabsorption cross section is calculated microscopically. As nucleon-nucleon interaction the semi-realistic central AV4' potential with S- and P-wave forces is taken. The interaction of the final 7-nucleon system is fully taken into account via the Lorentz Integral Transform (LIT) method. For the calculation of the LIT we use expansions in hyperspherical harmonics (HH) in conjunction with the HH effective interaction (EIHH) approach. The convergence of the LIT expansion is discussed in detail. The calculated cross section agrees quite well with the available experimental data, which cover an energy range from threshold up to 100 MeV.

PhysicsNuclear and High Energy PhysicsNuclear TheoryNuclear TheoryAb initioFOS: Physical sciencesFew-body systemsThreshold energyIntegral transformNuclear Theory (nucl-th)Cross section (physics)Ab initio quantum chemistry methodsPhotodisintegrationQuantum electrodynamicsAtomic physicsNucleon
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Ionization Energies of ClO and Cl2O2

1996

The ionization energies of chlorine oxide (ClO) and its dimer (Cl2O2) have been measured using monochromatic synchrotron radiation in the 10−20 eV energy regime in combination with photoionization mass spectrometry. The threshold energy of ClO+ (m/z = 51) is found at 10.85 ± 0.05 eV, whereas the ionization threshold of Cl2O2+ (m/z = 102) occurs at 11.05 ± 0.05 eV. The experimental values are compared to results from ab initio calculations, where three stable isomers of Cl2O2 are considered:  dichlorine peroxide (ClOOCl), chloryl chloride (ClClO2), and chlorine chlorite (ClOClO). The results indicate that the experimental threshold energy of Cl2O2+ is due to adiabatic ionization of ClOOCl. T…

Chlorine oxideChemistryAb initio quantum chemistry methodsIonizationGeneral EngineeringAnalytical chemistryAppearance energyPhotoionizationPhysical and Theoretical ChemistryIonization energyThreshold energyMass spectrometryThe Journal of Physical Chemistry
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