Search results for "Citation"

showing 10 items of 1710 documents

Luminescence of γ-radiation-induced defects in α-quartz

2004

Optical transitions associated with γ-radiation-induced defects in crystalline α-quartz were investigated by photoluminescence excited by both pulsed synchrotron radiation and steady-state light. After a 10 MGy γ-dose we observed two emissions at 4.9 eV (ultraviolet band) and 2.7 eV (blue band) excitable in the range of the induced absorption band at 7.6 eV. These two luminescence bands show a different temperature dependence: the ultraviolet band becomes bright below 80 K; the blue band increases below 180 K, but drops down below 80 K. Both emissions decay in a timescale of a few ns under pulsed excitation, however the blue band could also be observed in slow recombination processes and it…

Range (particle radiation)Photoluminescencebusiness.industryChemistrySynchrotron radiationCondensed Matter Physicsmedicine.disease_causeMolecular physicsAbsorption bandExcited statemedicineOptoelectronicsGeneral Materials ScienceLuminescencebusinessExcitationUltravioletJournal of Physics: Condensed Matter
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A rotating wheel system for the detection of spontaneously fissioning nuclides from heavy ion reactions

1981

Abstract A rotating wheel system for the detection of spontaneously fissioning reaction products from heavy ion reactions was developed. In this system products recoiling from a rotating target wheel are stopped in a catcher foil stack which can be rotated at various velocities up to 80 rotations per second. All products emitted within a wide emission cone are stopped in the catcher foils and are rotated into shielded positions with stationary fission-track detectors positioned on both sides of each rotating foil. This technique allows a sensitive detection of spontaneously fissioning nuclides over a broad range of half-lives from 1 ms to about 1 d. By post-bombardment exposure of the catch…

Range (particle radiation)Physics::Instrumentation and DetectorsChemistryDetectorGeneral Engineeringlaw.inventionNuclear physicsStack (abstract data type)lawShielded cableHeavy ionNuclideAtomic physicsNuclear ExperimentFOIL methodExcitationNuclear Instruments and Methods in Physics Research
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Luminescence of ZnO nanopowders

2004

Abstract The luminescence of ZnO nanocrystals prepared by different methods was studied under pulsed electron beam excitation. It is shown that the luminescence intensity depends on the nanocrystal sintering conditions and does not depend on the nanocrystal size within the range 10–50 nm. The relative luminescence intensities for the 3.32 eV (free exciton) and ∼3.20 eV (bound exciton) bands showed a dependence on nanocrystal size. The role of the nanocrystal surface in excitonic luminescence is discussed.

Range (particle radiation)RadiationMaterials scienceNanocrystalExcitonAnalytical chemistrySinteringElectronLuminescenceInstrumentationSpectral lineExcitationRadiation Measurements
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The influence of internal degrees of freedom on the unimolecular decay of the molecule–cluster compound Au8+CH3OH

2002

Time-resolved photodissociation measurements of the sequential reaction Au8+CH3OH→Au8+→Au7+ and the direct reaction Au8+→Au7+ have been performed for several excitation energies. The production rates and yields of the final state Au7+ in the sequential process are strongly influenced by the excitation energy deposited into the evaporated methanol molecule during the initial fragmentation step. Both the rate constants and yields can be fitted with a single parameter, the cluster–methanol binding energy.

Reaction rate constantFragmentation (mass spectrometry)ChemistryBinding energyPhotodissociationDegrees of freedom (physics and chemistry)General Physics and AstronomyPhysical chemistryMoleculePhysical and Theoretical ChemistryAtomic physicsExcitationIonThe Journal of Chemical Physics
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In search of proper pronunciation: students’ practices of soliciting help during read-aloud

2018


 
 
 This ar cle examines Finnish L2 learners’ interactional practices of flagging trouble in pronouncing words when reading aloud texts in English. Using conversation analysis, it describes how students employ three repair initiaon techniques – direct requests, trying out, and aborting the reading – as methods through which they mobilize teachers’ help in the form of a model pronunciation of the target word. By describing the sequential and temporal unfolding of read-aloud, the article presents an empirical way of tracing those classroom practices that students employ to develop their pronunciation skills of English in Finland. CA-based methodology that focuses on the inter…

Read aloudrepair initiationGeneral Energyconversation analysispronuncitationComputingMilieux_COMPUTERSANDEDUCATIONreading aloudArtikkelitPronunciationPsychologyLinguisticsAFinLA-teema
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The influence of Elfreda Chatman's theories: a citation context analysis

2018

The range of theoretical frameworks currently being used by researchers into information behaviour is abundant and diverse. We need to examine thoroughly the contribution of theories and models to further research, as this would help to improve future investigations in the field. This paper adopts this approach, by thoroughly examining the influence that Elfreda Chatman's three middle-range theories have had on subsequent research. A citation context analysis was carried out on the basis of those received by Information poverty theory, life in the round theory and normative behaviour theory. Analysis covered the year of publication, the type of work and the subject-matter of the citing docu…

Recuperació de la informacióPovertyCITES05 social sciencesGeneral Social SciencesContext (language use)Library and Information Sciences050905 science studiesField (geography)Computer Science ApplicationsStyle (sociolinguistics)EpistemologyInformació Teoria de laNormativeRelevance (information retrieval)Sociology0509 other social sciences050904 information & library sciencesCitation
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Mapping recent information behavior research: an analysis of co-authorship and cocitation networks

2015

There has been an increase in research published on information behavior in recent years, and this has been accompanied by an increase in its diversity and interaction with other fields, particularly information retrieval (HR). The aims of this study are to determine which researchers have contributed to producing the current body of knowledge on this subject, and to describe its intellectual basis. A bibliometric and network analysis was applied to authorship and co-authorship as well as citation and co-citation. According to these analyses, there is a small number of authors who can be considered to be the most productive and who publish regularly, and a large number of transient ones. Ot…

Recuperació de la informacióbusiness.industryComputer scienceDocumentaciómedia_common.quotation_subjectInformation scienceGeneral Social SciencesSubject (documents)Ciències de la informacióLibrary and Information SciencesData scienceCo-citationComputer Science ApplicationsInformation behaviorBody of knowledgeBibliometriaInformation retrievalCitationbusinessPublicationQualitative researchDiversity (politics)media_common
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Main Trends in Regional Innovation Systems: An Author Co-citation Analysis

2010

Regional Innovation Systems are increasingly attracting attention on behalf of accademics, practitioners and policy makers. This has produced a wide array of studies in the field, both regards the specific themes treated and the perspectives adopted. Though a number of sujective reviews of the field have been proposed, these tend to present the field according to the analysts' subjective biases and tends to meld what the field is with what the field should be. In order to overcome the limitations present in the subjective reviews proposed untill today, in this study we conduct an objective review of the main contributions to the Regional Innovation Systems fiels of studies.

Regional Innovation Systems Author co-citation analysis multidimensional scaling cluster analysis factor analysisSettore SECS-P/08 - Economia E Gestione Delle Imprese
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34 Early Gene Regulation in Retina and Choroid After Ashpyxia and Resuscitation in Newborn Piglets

2010

34 Early Gene Regulation in Retina and Choroid After Ashpyxia and Resuscitation in Newborn Piglets

Regulation of gene expressionResuscitationRetinaPathologymedicine.medical_specialtyintegumentary systembusiness.industryanimal diseaseseye diseasesfluids and secretionsmedicine.anatomical_structurePediatrics Perinatology and Child Healthmedicinesense organsChoroidbusinessPediatric Research
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Allowing End-Users to Actively Participate within the Elicitation of Pervasive System Requirements through Immediate Visualization

2009

Efficient requirements engineering activities are essential in order to develop software systems that properly satisfy end-user needs. End-users lack knowledge about requirements engineering techniques or computation in general, and it is very important that they actively participate in the requirements elicitation process because they are the "owners" of the problem. In this paper, we present a tool-supported requirements elicitation technique that is centered on end-users and that allows them to describe the main characteristics of pervasive systems. In addition, we provide end-users with an immediate natural visualization of the described requirements. Furthermore, we present a requireme…

Requirements managementRequirementNon-functional requirementRequirements traceabilityRequirements engineeringComputer sciencebusiness.industrySoftware requirements specificationRequirements elicitationSoftware engineeringbusinessRequirements analysis2009 Fourth International Workshop on Requirements Engineering Visualization
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