0000000000959824

AUTHOR

O. Davies

showing 6 related works from this author

Efficient generation of energetic ions in multi-ion plasmas by radio-frequency heating

2017

We describe a new technique for the efficient generation of high-energy ions with electromagnetic ion cyclotron waves in multi-ion plasmas. The discussed ‘three-ion’ scenarios are especially suited for strong wave absorption by a very low number of resonant ions. To observe this effect, the plasma composition has to be properly adjusted, as prescribed by theory. We demonstrate the potential of the method on the world-largest plasma magnetic confinement device, JET (Joint European Torus, Culham, UK), and the high-magnetic-field tokamak Alcator C-Mod (Cambridge, USA). The obtained results demonstrate efficient acceleration of 3He ions to high energies in dedicated hydrogen–deuterium mixtures.…

Astrophysical plasmasTokamakradio-frequency heatingCyclotronJoint European TorusPlasma heatingGeneral Physics and AstronomyFREQUENCY114 Physical sciences01 natural sciences7. Clean energyMagnetically confined plasmas010305 fluids & plasmaslaw.inventionIonPHYSICSPhysics and Astronomy (all)FUSIONMODE CONVERSIONlawPhysics::Plasma Physics0103 physical sciencesDielectric heating010306 general physicsPhysics[PHYS]Physics [physics]ta114Solar flare:Física [Àrees temàtiques de la UPC]Plasma dynamicsmulti-ion plasmasSettore FIS/01 - Fisica SperimentaleMagnetic confinement fusionPlasmaHE-3-RICH SOLAR-FLARESTècniques de plasmaJETCYCLOTRON RANGETOKAMAKPhysics::Space PhysicsAtomic physicsHE-3-RICH SOLAR-FLARES; MODE CONVERSION; CYCLOTRON RANGE; FUSION; JET; FREQUENCY; TOKAMAK; PHYSICS
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Novel method for determination of tritium depth profiles in metallic samples

2019

Tritium accumulation in fusion reactor materials is considered a serious radiological issue, therefore a lot of effort has been concentrated on the development of radiometric techniques. A novel method, based on gradual dissolution, for the determination of the total tritium content and its depth profiles in metallic samples is demonstrated. This method allows for the measurement of tritium in metallic samples after their exposure to a hydrogen and tritium mixture, tritium containing plasma or after irradiation with neutrons resulting in tritium formation. In this method, successive layers of metal are removed using an appropriate etching agent in the controlled regime and the amount of evo…

inorganic chemicalsfusionNuclear and High Energy PhysicsMaterials scienceNuclear engineeringchemistry.chemical_elementheliumBlanket114 Physical sciences01 natural sciences010305 fluids & plasmasblanketMetalirradiated berylliumjet0103 physical sciencespolycyclic compounds010306 general physicsHeliumbreeding blanketJet (fluid)Fusiontritiumbehaviororganic chemicalshydrogen diffusiontemperatureiter-like-wallFusion powerfirst wallberylliumCondensed Matter Physicschemistryvisual_arttransportcardiovascular systemvisual_art.visual_art_mediumdepth profileTritiumBerylliumNuclear Fusion
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Comparison of the structure of the plasma-facing surface and tritium accumulation in beryllium tiles from JET ILW campaigns 2011-2012 and 2013-2014

2019

In this study, beryllium tiles from Joint European Torus (JET) vacuum vessel wall were analysed and compared regarding their position in the vacuum vessel and differences in the exploitation conditions during two campaigns of ITER-Like-Wall (ILW) in 2011-2012 (ILW1) and 2013-2014 (ILW2) Tritium content in beryllium samples were assessed. Two methods were used to measure tritium content in the samples - dissolution under controlled conditions and tritium thermal desorption. Prior to desorption and dissolution experiments, scanning electron microscopy and energy dispersive x-ray spectroscopy were used to study structure and chemical composition of plasma-facing-surfaces of the beryllium sampl…

Fuel retentionPhysics::Medical Physics01 natural sciencesQuantitative Biology::Cell Behavior010305 fluids & plasmasiter-like walljoint european torusRETENTION010302 applied physicsJet (fluid)tritiumPhysicsMechanicsSurface (topology)Fusion Plasma and Space Physicslcsh:TK9001-9401surgical procedures operativecardiovascular systemJoint European TorusTritiumBerylliumBerylliumNuclear and High Energy PhysicsretentionTechnology and Engineeringanimal structuresMaterials scienceQuantitative Biology::Tissues and OrgansMaterials Science (miscellaneous)Joint European Toruschemistry.chemical_elementTritium114 Physical sciencesGeneral Relativity and Quantum CosmologyFusion plasma och rymdfysik0103 physical sciencesddc:530ITER-LIKE-WALLITER-like walltechnology industry and agriculturePlasmaiter-like-wallberylliumTRANSPORTfuel retentionbody regionsNuclear Energy and Engineeringchemistrytransportlcsh:Nuclear engineering. Atomic power
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Comparison of European ICU patients in 2012 (ICON) versus 2002 (SOAP)

2018

Purpose: To evaluate differences in the characteristics and outcomes of intensive care unit (ICU) patients over time. Methods: We reviewed all epidemiological data, including comorbidities, types and severity of organ failure, interventions, lengths of stay and outcome, for patients from the Sepsis Occurrence in Acutely ill Patients (SOAP) study, an observational study conducted in European intensive care units in 2002, and the Intensive Care Over Nations (ICON) audit, a survey of intensive care unit patients conducted in 2012. Results: We compared the 3147 patients from the SOAP study with the 4852 patients from the ICON audit admitted to intensive care units in the same countries as those…

MaleOriginalEpidemiology[SDV]Life Sciences [q-bio]HSJ UCIlnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4]MULTICENTERclinical outcomemortality rateCritical Care and Intensive Care Medicineintensive care unitlaw.invention0302 clinical medicineSeverity of diseaselawEpidemiologymiddle agedMedicine and Health SciencesFAILURE030212 general & internal medicineHospital Mortalityintensive care units -- analysis -- epidemiology -- mortalityGeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)CODEScomparative studyintensive careMedicine(all)multilevel analysiIncidenceadultSciences bio-médicales et agricolesIntensive care unit3. Good healthEuropesepsaIntensive Care UnitsfemaleCohortenote intenzivne terapije -- analiza -- epidemiologija -- umrljivostHumanAdultmedicine.medical_specialtyseverity of diseaseCritical CareSepsiIntensive Care UnitUNITED-STATES610 Medicine & healthINTENSIVE-CAREEuropeanArticleSepsisEpidemiology; Sepsis; Severity of disease03 medical and health sciencesAll institutes and research themes of the Radboud University Medical Centerlength of staymaleEpidemiology; Sepsis; Severity of disease; Adult; Europe; Hospital Mortality; Humans; Length of Stay; Male; Critical Care; Intensive Care Units; SepsisAnesthesiologyIntensive careSepsisSCOREmedicineudc:614.2Humanshumanoutcome assessmentSeptic shockbusiness.industrySEPTIC SHOCK030208 emergency & critical care medicineLength of Staymedicine.diseaseTRENDSmajor clinical studySEVERE SEPSIScomorbidity assessmentEmergency medicineEpidemiology; Sepsis; Severity of disease; Critical Care and Intensive Care MedicineObservational studyCLAIMSbusinessSepsis;Severity of disease;Epidemiologyresnost bolezni
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Assessment of the worldwide burden of critical illness: The Intensive Care Over Nations (ICON) audit

2014

Item does not contain fulltext BACKGROUND: Global epidemiological data regarding outcomes for patients in intensive care units (ICUs) are scarce, but are important in understanding the worldwide burden of critical illness. We, therefore, did an international audit of ICU patients worldwide and assessed variations between hospitals and countries in terms of ICU mortality. METHODS: 730 participating centres in 84 countries prospectively collected data on all adult (>16 years) patients admitted to their ICU between May 8 and May 18, 2012, except those admitted for fewer than 24 h for routine postoperative monitoring. Participation was voluntary. Data were collected daily for a maximum of 28 da…

Pulmonary and Respiratory Medicinemedicine.medical_specialtyCritical Illnesshealth care facilities manpower and servicesPopulationlnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4]Critical care european intensive care icon studyComorbidityintensive care medicineGlobal HealthMOF; sepsis; critically ill[SDV.MHEP.PSR]Life Sciences [q-bio]/Human health and pathology/Pulmonology and respiratory tractICON Intensive CareArticleSepsisCohort StudiesOutcome Assessment (Health Care)Intensive careSepsisOutcome Assessment Health CareEpidemiologyHealth careSettore MED/41 - ANESTESIOLOGIAmedicineGlobal healthcritical illness mortalityHumansHospital MortalityeducationIntensive care medicineeducation.field_of_studyMedical Auditbusiness.industryIntensive Caremedicine.diseaseComorbidity3. Good healthIntensive Care UnitsICONbusinessCohort study
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Modelling of JET hybrid plasmas with emphasis on performance of combined ICRF and NBI heating

2018

International audience; During the 2015--2016 JET campaigns, many efforts have been devoted to the exploration of high-performance plasma scenarios envisaged for DT operation in JET. In this paper, we review various key recent hybrid discharges and model the combined ICRF NBI heating. These deuterium discharges with deuterium beams had the ICRF antenna frequency tuned to match the cyclotron frequency of minority H at the centre of the tokamak coinciding with the second harmonic cyclotron resonance of D. The modelling takes into account the synergy between ICRF and NBI heating through the second harmonic cyclotron resonance of D beam ions, allowing us to assess its impact on the neutron rate…

Nuclear and High Energy PhysicsLight nucleusfusionPlasma heatingicrf heatingNuclear engineeringion-cyclotron rangeCyclotronJET hybrid plasmaICRF heating; NBI heating; JET hybrid plasmas; fusion enhancement; ION-CYCLOTRON RANGE; ENHANCEMENT; FUSION7. Clean energy01 natural sciences010305 fluids & plasmaslaw.inventionICRF heatingfusion enhancementdt plasmaslawNBI heating0103 physical sciences010306 general physicsjet hybrid plasmastokamakenhancementfusion enhancement; ICRF heating; JET hybrid plasmas; NBI heatingnbi heatingJet (fluid)Emphasis (telecommunications)PlasmaCondensed Matter PhysicsJET hybrid plasmasSettore ING-IND/20 - Misure e Strumentazione NucleariresonanceEnvironmental science[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
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