Search results for " Emission"

showing 10 items of 1496 documents

Kinetics of phase transitions in vitreous chalcogenide semiconductors AsxSe100m-x-yBiyas studied by the differential thermal analysis and exoelectron…

2011

Kinetics of glass transition (retrification) in chalcogenide semiconductors AsxSe100-x-yBy (x = 20 or 30, and y = 0 and 1) has been investigated by parallel differential thermal analysis (DTA) and exoelectron emission (EEE) measurements. EEE is a surface effect accompanying the structural transformations in the surface layer, whereas the DTA technique gives information about the transformations occurring in the volume of the sample. Temperature dependencies of the DTA signal and of the EEE intensity have been determined and the values of the activation energy for both the volume and the surface retrification have been determined by the Ozawa method for each of the four investigated material…

HistoryPhase transitionMaterials scienceChalcogenideAnalytical chemistryActivation energyComputer Science ApplicationsEducationchemistry.chemical_compoundchemistryDifferential thermal analysisThermal stabilitySurface layerGlass transitionExoelectron emissionJournal of Physics: Conference Series
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Study of exotic decay of Cs isotope close to the proton drip line

2020

6 pags., 6 figs. -- 27th International Nuclear Physics Conference (INPC2019) 29 July - 2 August 2019, Glasgow, UK

HistoryProtonGround stateParticle emissionsNuclear TheoryExotic decayProton spectraSpallation reactionsCesium01 natural sciencesLanthanum compounds3100EducationNuclear physicsParticle emissionGermanium compoundsGamma detectors0103 physical sciencesNuclear Physics - ExperimentSpallation010306 general physicsNuclear ExperimentLine (formation)PhysicsLarge Hadron ColliderIsotope010308 nuclear & particles physicsCharged particle arraysCharged particleComputer Science ApplicationsPhysics::Accelerator PhysicsTime distributionFísica nuclearUnbound stateGround stateydinfysiikka
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Thermal activated carrier transfer between InAs quantum dots in very low density samples

2010

In this work we develop a detailed experimental study of the exciton recombination dynamics as a function of temperature on QD-ensembles and single QDs in two low density samples having 16.5 and 25 dots/¼m2. We corroborate at the single QD level the limitation of the exciton recombination time in the smallest QDs of the distribution by thermionic emission (electron emission in transient conditions). A portion of these emitted carriers is retrapped again in other (larger) QDs, but not very distant from those emitting the carriers, because the process is limited by the diffusion length at the considered temperature.

HistoryWork (thermodynamics)Condensed Matter::Otherbusiness.industryChemistryExcitonThermionic emissionElectron66.30.H- Self-diffusion and ionic conduction in nonmetals78.67.Hc Quantum dotsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectMolecular physicsComputer Science ApplicationsEducationCondensed Matter::Materials Science78.55.Cr III-V semiconductorsQuantum dotThermalOptoelectronics71.35.-y Excitons and related phenomenaDiffusion (business)businessRecombination79.40.+z Thermionic emissionJournal of Physics: Conference Series
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Experimental study of hydrogen plasma breakdown in a 2.45 GHz microwave discharge

2013

Temporal evolution of microwave-plasma coupling, vacuum ultraviolet (VUV) light emission and plasma electron temperature and density is reported for a 2.45GHz microwave hydrogen discharge pulsed at 50Hz. Directional couplers, a VUV spectrometer and a Langmuir probe are used for the diagnostics of the plasma breakdown. A 5‐10 µs transient peak of light emission exceeding the steady-state intensity by a factor of 3.3 is observed in coincidence with an abrupt drop in the microwave electric field. Observed light emission intensities combined with cross section data indicate that the electron temperature during the breakdown transient exceeds the steady-state value of 4‐6eV by a factor 3, which …

HydrogenChemistrybusiness.industrychemistry.chemical_elementAstrophysics::Cosmology and Extragalactic AstrophysicsPlasmaCondensed Matter Physicssymbols.namesakeOpticsPhysics::Plasma PhysicsElectric fieldsymbolsElectron temperatureLangmuir probeLight emissionPlasma diagnosticsAtomic physicsbusinessMicrowavePlasma Sources Science and Technology
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Plasma distributions observed in a 2.45 GHz hydrogen discharge

2014

The existence of various spatial distributions of hydrogen plasma in a pulsed 2.45 GHz microwave discharge is demonstrated. The data has been obtained through optical emission diagnostics utilizing an ultra-fast CCD camera system with multi-channel plate (MCP) intensifiers, and a wavelength-filtered photodiode recording temporal light emission signals of hydrogen atoms and molecules. It has been observed that the magnetic field topology and strength are determining the transitions between different plasma patterns and spectral saturation times while neutral gas pressure and microwave power show a weaker influence on the profiles but affect the emitted light intensity.

HydrogenPhysics::Instrumentation and DetectorsChemistrychemistry.chemical_elementPlasmaCondensed Matter PhysicsPhotodiodelaw.inventionMagnetic fieldLight intensityPhysics::Plasma PhysicslawLight emissionAtomic physicsSaturation (magnetic)MicrowavePlasma Sources Science and Technology
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Total CO2output from Vulcano island (Aeolian Islands, Italy)

2012

[1] Total CO2 output from fumaroles, soil gas, bubbling gas discharges and water dissolved gases discharged from the island, was estimated for Vulcano island, Italy. The CO2 emission from fumaroles from the La Fossa summit crater was estimated from the SO2 crater output, while CO2 discharged through diffuse soil emission was quantified on the basis of 730 measurements of CO2 fluxes from the soil of the island, performed by using the accumulation chamber method. The results indicate an overall output of ≅500 t day−1 of CO2 from the island. The main contribution to the total CO2 output comes from the summit area of the La Fossa cone (453 t day−1), with 362 t day−1 from crater fumaroles and 91…

HydrologyGeophysicsImpact craterSoil emissionGeochemistry and PetrologyMolar ratioChamber methodSoil gasMineralogyAeolian processesSeawaterGeologyFumaroleGeochemistry, Geophysics, Geosystems
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CO2 output discharged from Stromboli Island (Italy)

2013

Abstract Total CO 2 output from soil gas and plume, discharged from the Stromboli Island, was estimated. The CO 2 emission of the plume emitted from the active crater was estimated on the basis of the SO 2 crater output and C/S ratio, while CO 2 discharged through diffuse soil emission was quantified on the basis of 419 measurements of CO 2 fluxes from the soil of the whole island, performed by using the accumulation chamber method. The results indicate an overall output of ≅ 416 t day − 1 of CO 2 from the island. The main contribution to the total CO 2 output comes from the summit area (396 t day − 1 ), with 370 t/day from the active crater and 26 t day − 1 from the Pizzo sopra La Fossa so…

HydrologySoil emissionImpact craterGeochemistry and PetrologyChamber methodSoil gasCO2 flux CO2 output Stromboli Island SO2 fluxCo2 fluxGeologyGeologyPlumeChemical Geology
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Volcanic gas emissions and degassing dynamics at Ubinas and Sabancaya volcanoes; implications for the volatile budget of the central volcanic zone

2017

Abstract Emission of volcanic gas is thought to be the dominant process by which volatiles transit from the deep earth to the atmosphere. Volcanic gas emissions, remain poorly constrained, and volcanoes of Peru are entirely absent from the current global dataset. In Peru, Sabancaya and Ubinas volcanoes are by far the largest sources of volcanic gas. Here, we report the first measurements of the compositions and fluxes of volcanic gases emitted from these volcanoes. The measurements were acquired in November 2015. We determined an average SO 2 flux of 15.3 ± 2.3 kg s − 1 (1325-ton day − 1 ) at Sabancaya and of 11.4 ± 3.9 kg s − 1 (988-ton day − 1 ) at Ubinas using scanning ultraviolet spectr…

IASI010504 meteorology & atmospheric sciencesSabancayaEarth scienceGeochemistry010502 geochemistry & geophysics01 natural sciencesVolcanic GasesAtmospherechemistry.chemical_compoundFlux (metallurgy)Geochemistry and Petrology[SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/VolcanologyVolcanic degassingeventGeophysic0105 earth and related environmental sciences[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphereevent.disaster_typeTrail By Firegeographygeography.geographical_feature_categoryGas emissionsUV-cameraUbinaGeophysicsCarbon dioxidechemistryVolcanoUbinasDOAS13. Climate actionCarbon dioxideMulti-GASGeologyEarth (classical element)Journal of Volcanology and Geothermal Research
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Beta-decay of light nuclei close to the proton drip-line: 40Ti and 35Ca

1998

The s-decay of40Ti and35Ca have been studied at the LISE3 spectrometer at GANIL. The decay schemes were deduced from the observed s-delayed proton and γ emission of40Ti and35Ca into the ground and first excited states of39Ca and34Ar, respectively. The Gamow-Teller strength functionB(GT) of the40Ti s-decay extracted from the s-decay branching ratios and the precisely measured40Ti half-life, provides for the first time an experimental calibration of the neutrino detection efficiency for the ICARUS solar neutrino detector.

ICARUSPhysicsDecay schemePhysics::Instrumentation and Detectors010308 nuclear & particles physicsSolar neutrino[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]7. Clean energy01 natural sciencesBeta decayNuclear physicsNeutrino detectorExcited state0103 physical sciencesHigh Energy Physics::ExperimentPositron emissionAtomic physicsProton emissionNuclear Experiment010306 general physicsComputingMilieux_MISCELLANEOUS
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124I Radiolabeling of a AuIII‐NHC Complex for In Vivo Biodistribution Studies†

2020

Abstract AuIII complexes with N‐heterocyclic carbene (NHC) ligands have shown remarkable potential as anticancer agents, yet their fate in vivo has not been thoroughly examined and understood. Reported herein is the synthesis of new AuIII‐NHC complexes by direct oxidation with radioactive [124I]I2 as a valuable strategy to monitor the in vivo biodistribution of this class of compounds using positron emission tomography (PET). While in vitro analyses provide direct evidence for the importance of AuIII‐to‐AuI reduction to achieve full anticancer activity, in vivo studies reveal that a fraction of the AuIII‐NHC prodrug is not immediately reduced after administration but able to reach the major…

Imaging Agents | Hot Paperpositron emission tomography010405 organic chemistryChemistryGeneral ChemistryProdrug010402 general chemistryanticancer01 natural sciencesCombinatorial chemistryCatalysisIn vitro3. Good health0104 chemical sciencesIn vivoIn vivo biodistributionSettore CHIM/03 - Chimica Generale E InorganicametallodrugsN-heterocyclic carbenesanticancer; metallodrugs; N-heterocyclic carbenes; positron emission tomography; radiochemistryradiochemistryResearch ArticlesResearch ArticleAngewandte Chemie (International Ed. in English)
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