Search results for "Clusters"

showing 10 items of 1274 documents

Vibrational population of H 2 + after electroionization of thermal H2

1993

In an ion trap experiment we have determined the vibrational population of the lowest 9 vibrational levels of H2+. We used photodissociation of the trapped molecules by 248 nm light from an excimer laser and the dependence of the photodissociation cross section from the vibrational state. Our results are in good agreement to calculations, which are based on the Franck-Condon principle, but include a variation of the internuclear distance in the transition matrix element.

education.field_of_studyMaterials scienceExcimer lasermedicine.medical_treatmentPopulationPhotodissociationStochastic matrixAtomic and Molecular Physics and OpticsCross section (physics)Physics::Atomic and Molecular ClustersmedicineVibrational energy relaxationMoleculePhysics::Atomic PhysicsIon trapPhysics::Chemical PhysicsAtomic physicseducationZeitschrift f�r Physik D Atoms, Molecules and Clusters
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Hartree-Fock calculations and photoelectron spectra of SSO and NSF

1974

Results from ab initio Hartree-Fock calculations on the ground states of SSO and NSF are reported. The calculations employ large basis sets of Gaussian functions of essentially double zeta quality. The photoelectron spectra of the bent triatomic molecules with 18 valence electrons, i.e. SSO, NSF, O3, SO2, NSCl are compared. Further experimental details of the photoelectron spectrum of SSO are presented and an assignment of the observed ionic states of SSO⊕ is attempted. The calculated dissociation energies, dipole moments and the population analyses are given. The correlation effect is qualitatively discussed in connection with the applicability of Koopmans' theorem for the bent tri-atomic …

education.field_of_studyPhotoemission spectroscopyChemistryTriatomic moleculePopulationAb initioHartree–Fock methodSpectral lineDipolePhysics::Atomic and Molecular ClustersPhysics::Atomic PhysicsChiropracticsPhysics::Chemical PhysicsPhysical and Theoretical ChemistryAtomic physicsValence electroneducationTheoretica Chimica Acta
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Photodynamics of a Molecular Water-Soluble Nanocluster Identified as Au130(pMBA)50

2015

Photodynamics of a highly monodisperse sample of a water-soluble gold nanocluster tentatively identified as Au130(pMBA)50 (pMBA = p-mercaptobenzoic acid) was studied by mid-IR transient absorption spectroscopy with visible excitation. The observed long-lived excited states (>1 ns) indicate a molecular behavior of the cluster. By combining the transient absorption data with DFT calculation results the observed relaxation dynamics could be fully explained by identifying several relaxation processes involving singlet and triplet manifolds. The results indicate that the cluster may have interesting transient magnetic properties due to a long-lived triplet population.

education.field_of_studyta114ChemistryPopulationRelaxation (NMR)Analytical chemistrySurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyChemical physicsExcited stateUltrafast laser spectroscopyCluster (physics)mid-IR transient absorption spectroscopySinglet statePhysical and Theoretical ChemistrySpectroscopyeducationta116gold nanoclustersExcitationJournal of Physical Chemistry C
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Fibre break failure processes in unidirectional composites: evaluation of critical damage states

2016

Earlier work which successfully modelled the kinetics of fibre breakage in unidirectional composites under monotonic tensile loading has been extended to quantify the kinetics of fibre failure during both monotonic and sustained tensile loading. In both cases, failure was seen to occur when a critical density of large clusters (more than 16 fibres are broken within the representative volume element) of fibre breaks developed. However, in monotonic loading failure occurred very quickly after the first development of these large clusters, whereas under sustained loading the composite could accommodate greater levels of large clusters because of the lower applied load. This article is part of …

effects of monotonic and sustained tensile loadingWork (thermodynamics)Materials scienceclusters of breaksGeneral MathematicsComposite numberfibre breakscritical damageGeneral Engineering[ PHYS.COND.CM-MS ] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]General Physics and AstronomyStructural integrity02 engineering and technology021001 nanoscience & nanotechnology020303 mechanical engineering & transports0203 mechanical engineeringBreakageUltimate tensile strength[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Representative elementary volumeComposite material0210 nano-technology
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Embedded-atom calculations of Auger and x-ray photoemission shifts for metallic elements

1982

Change in self-consistent-field energy density-functional calculations are reported for Auger and core-level binding-energy shifts in sp-bonded metals. The basic model, atom in jellium vacancy, gives good agreement with experiment, especially in the Auger case. The chemical and relaxation contributions to the shifts are discussed, and the extra-atomic response is analyzed in detail, both in position and energy space. The adequacy of the "excited-atom" approach to the energy shifts is discussed. Peer reviewed

embedded-atom calculationsX ray photoemissionMaterials sciencePhysicsInverse photoemission spectroscopyAngle-resolved photoemission spectroscopyAugerMetalvisual_artAtomPhysics::Atomic and Molecular Clustersvisual_art.visual_art_mediumPhysics::Atomic PhysicsAtomic physicssp-bonded metalsPhysical Review B
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Country branding in export promotion : case Food From Finland

2017

Globalisaation myötä mielikuvat eri maista vaikuttavat kasvavassa määrin kuluttajien jokapäiväisiin valintoihin ympäri maailmaa. Edistääkseen positiivista mielikuvaa, useat maat tekevät maabrändityötä, joka ulottuu matkailumarkkinoinnista vienninedistämiseen ja ulkomaisten investointien houkuttelemiseen. Tämän tutkimuksen tavoitteina oli valottaa suomalaisten elintarvikeviejien suhdetta kotimaansa maabrändiin sekä tarkastella vientiyritysten ja vienninedistämistoimien roolia maabrändin kehittämistyössä. Tutkimuksen kohteena on Finpron elintarviketeollisuuden vienninedistämisohjelma Food From Finland ja tutkimuksen empiirinen aineisto koostuu kahdeksasta laadullisesta yrityshaastattelusta. T…

export intermediaryruokaeconomic clustersSuomibrändäysalkuperämaaviennin edistäminenfood brandingexport promotioncountry brandingcountry-of-origin effect
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External Changes and R&I Inter-Organizational Network Dynamics: The Case of EU R&I Policy Change

2022

The paper seeks to understand in what way changes in EU innovation policy incentives affect the EU R&I inter-organizational network dynamics. In particular, the study’s empirical settings are the two innovative inter-organizational networks that connect knowledge actors financed through two EU Framework Programs: the 7th Framework Program (or FP7), and the 8th Framework Program, named HORIZON 2020 (or H2020). Using a dataset of more than 22,228 unique projects in FP7 and 22,153 in H2020, we constructed two collaboration networks. We apply network analysis as a research instrument to identify and measure the fundamental structural properties and evolutionary dynamics of whole networks. I…

external changenetwork clusters or communitiesR&ampI inter-organizational networkEU Framework Programnetwork structure evolutionary network dynamicSettore SECS-P/08 - Economia E Gestione Delle Imprese
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REFLEX Galaxy Cluster Survey catalogue

2004

We present the catalogue of the REFLEX Cluster Survey providing information on the X-ray properties, redshifts, and some identification details of the clusters in the REFLEX sample. The catalogue describes a statistically complete X-ray flux-limited sample of 447 galaxy clusters above an X-ray flux of 3x10^-12^erg/s/cm^2^ (0.1 to 2.4keV) in an area of 4.24ster in the southern sky. The cluster candidates were first selected by their X-ray emission in the ROSAT-All Sky Survey and subsequently spectroscopically identified in the frame of an ESO key programme. Previously described tests have shown that the sample is more than 90% complete and there is a conservative upper limit of 9% on the fra…

galactic and extragalactic astronomyAstrophysics and AstronomyAstrophysics::High Energy Astrophysical PhenomenaPhysicsOptical observationGalaxy clustersAstrophysics::Cosmology and Extragalactic AstrophysicsSurveysX-ray sourcesobservational astronomyX ray sourcesNatural SciencescosmologyAstrophysics::Galaxy Astrophysics
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GES: pre-main-sequence clusters [Fe/H]

2017

The radial metallicity distribution in the Galactic thin disc represents a crucial constraint for modelling disc formation and evolution. Open clusters allow us to derive both the radial metallicity distribution and its evolution over time. In this paper we perform the first investigation of the present-day radial metallicity distribution based on [Fe/H] determinations in late type members of pre-main-sequence clusters. Because of their youth, these clusters are therefore essential for tracing the current inter-stellar medium metallicity. We used the products of the Gaia-ESO Survey analysis of 12 young regions (age<100Myr), covering Galactocentric distances from 6.67 to 8.70kpc. For the fir…

galactic and extragalactic astronomyAstrophysics and AstronomyPhysicsAstrophysics::Instrumentation and Methods for AstrophysicsChemical abundancesAstrophysics::Cosmology and Extragalactic AstrophysicsMilky Way Galaxystellar astronomyInterdisciplinary AstronomyEffective temperatureOpen star clustersobservational astronomyAstrophysics::Earth and Planetary AstrophysicsNatural SciencesAstrophysics::Galaxy Astrophysics
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Gaia-ESO Survey. Parameters for cluster members

2016

The nature of the metallicity gradient inside the solar circle (R_GC_<8kpc) is poorly understood, but studies of Cepheids and a small sample of open clusters suggest that it steepens in the inner disk. We investigate the metallicity gradient of the inner disk using a sample of inner disk open clusters that is three times larger than has previously been studied in the literature to better characterize the gradient in this part of the disk. We used the Gaia-ESO Survey (GES) [Fe/H] values and stellar parameters for stars in 12 open clusters in the inner disk from GES-UVES data. Cluster mean [Fe/H] values were determined based on a membership analysis for each cluster. Where necessary, distance…

galactic and extragalactic astronomyAstrophysics and AstronomyRadial velocityPhysicsChemical abundancesexoplanet astronomystellar astronomyMilky Way GalaxyInterdisciplinary Astronomyobservational astronomyOpen star clustersEffective temperatureAstrophysics::Earth and Planetary AstrophysicsNatural SciencesAstrophysics::Galaxy Astrophysics
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