Search results for "Rayos X"

showing 10 items of 19 documents

Search for high energy cosmic muon neutrinos from variable gamma-ray sources and time calibration of the optical modules of the ANTARES telescope

2015

325 páginas. Tesis Doctoral del Departamento de Física Atómica, Molecular y Nuclear de la Universidad de Valencia y del Instituto de Física Corpuscular (IFIC).

ANTAREStelescopios de neutrinosAGNsAstrophysics::High Energy Astrophysical PhenomenablazarsFísica experimental de Altas Energíasneutrino telescopesAstrophysics::Instrumentation and Methods for AstrophysicsneutrinosNebulosa del CangrejoXRBsX-ray binaries:FÍSICA::Física de altas energías [UNESCO]UNESCO::FÍSICA::Física de altas energíasCrab Pulsar Wind Nebulabinarias de rayos X
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Caracterización mineralógica de materias primas cerámicas por métodos cuantitativos de difracción de rayos x

2002

[ES] El objetivo de este trabajo es la caracterización de fases minerales presentes en materias primas utilizadas en la industria cerámica. Para ello se utilizan dos métodos cuantitativos basados en la difracción de rayos X, el método de Rietveld y un método sin estándar. Los resultados obtenidos por difracción rayos X de estos materiales policristalinos se comparan con los correspondientes análisis químicos y la composición normativa calculada. La precisión y reproducibilidad de los resultados obtenidos, en concordancia con los del análisis químico, son una de las más importantes ventajas de la difractometría cuantitativa que facilitan su utilización en la industria cerámica en el control …

Actual and normative mineralogical compositionsCeramic raw materialsQuantitative X-ray diffractionCuantitativa por difracción de rayos XComposiciones mineralógicas reales y normativasMaterias primas cerámicas
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Accreting X-Ray pulsars. The high energy picture

2007

El objetivo principal de esta tesis ha sido el estudio del comportamiento transitorio durante estallidos de distinto tipo, de una selección de pulsares acretores en rayos X, localizados en el plano galáctico.Con ello se pretende haber avanzado hacia una explicación más clara de la naturaleza de estas objetos binarios de alta masa (con estrella de neutrones como objeto compacto), así como de los mecanismos físicos que operan en este escenario. Para todo esto se han analizado datos de dos misiones espaciales:INTEGRA Y RXTE.El segundo objetivo ha sido el estudio de la zona del brazo galactico de Scutum. Al ser esta una región de fuerte absorción se cree de la existencia de sistemas del tipo an…

Astronomíacosmologia y cosmogoniafuentes de rayos xAstronomia y astrofísica52cosmología y cosmogoníaestrellas doblesastronomía y astrofísica
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The pre-outburst flare of the A 0535+26 August/September 2005 outburst

2008

We study the spectral and temporal behavior of the High Mass X-ray Binary A 0535+26 during a `pre-outburst flare' which took place ~5 d before the peak of a normal (type I) outburst in August/September 2005. We compare the studied behavior with that observed during the outburst. We analyse RXTE observations that monitored A 0535+26 during the outburst. We complete spectral and timing analyses of the data. We study the evolution of the pulse period, present energy-dependent pulse profiles both at the initial pre-outburst flare and close to outburst maximum, and measure how the cyclotron resonance-scattering feature (hereafter CRSF) evolves. We present three main results: a constant period P=…

Astrophysics::High Energy Astrophysical PhenomenaX-ray binarymagnetic fields [Stars]FOS: Physical sciencesChamp magnetiqueAstrophysicsPhoton energyAstrophysicslaw.inventionPulse periodAccretion disclaw:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Fuentes de Rayos X [UNESCO]X-rays : binaries; Stars : magnetic fields; Stars : individual : A 0535+26UNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Fuentes de Rayos XAstrophysics::Solar and Stellar AstrophysicsSpectral analysisPhysicsAstrophysics (astro-ph)Astronomy and AstrophysicsSpace and Planetary ScienceHigh massbinaries [X-rays]individual : A 0535+26 [Stars]UNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::EstrellasFlare:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Estrellas [UNESCO]
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High-pressure structural, elastic, and thermodynamic properties of zircon-type HoPO4 and TmPO4

2017

[EN] Zircon-type holmium phosphate (HoPO4) and thulium phosphate (TmPO4) have been studied by single-crystal x-ray diffraction and ab initio calculations. We report on the influence of pressure on the crystal structure, and on the elastic and thermodynamic properties. The equation of state for both compounds is accurately determined. We have also obtained information on the polyhedral compressibility which is used to explain the anisotropic axial compressibility and the bulk compressibility. Both compounds are ductile and more resistive to volume compression than to shear deformation at all pressures. Furthermore, the elastic anisotropy is enhanced upon compression. Finally, the calculation…

DiffractionZirconEquation of stateMaterials scienceEcuación de estadoThermodynamicsFOS: Physical sciences02 engineering and technologyCrystal structurezircon01 natural sciencesCondensed Matter::Materials ScienceAb initio quantum chemistry methods0103 physical sciencesGeneral Materials Science010306 general physicsAnisotropySofteningOrthophosphateCondensed Matter - Materials ScienceEquation of stateorthophosphateElastic propertiesMaterials Science (cond-mat.mtrl-sci)Difracción de rayos X021001 nanoscience & nanotechnologyCondensed Matter PhysicsCompression (physics)Cálculos ab initioX-ray diffractionHigh pressureFISICA APLICADAZirconioCompressibilityOrtofosfatosAb initio calculationselastic properties0210 nano-technologyPropiedades elásticasAlta presión
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Unveiling the nature of six HMXBs through IR spectroscopy

2008

The International Gamma-Ray Astrophyiscs Laboratory (INTEGRAL) is discovering a large number of new hard X-ray sources, many of them being HMXBs. The identification and spectral characterization of their optical/infrared counterparts is a necessary step to undertake detailed study of these systems. In particular, the determination of the spectral type is crucial in the case of the new class of Supergiant Fast X-ray Transients (SFXTs), which show X-ray properties common to other objects. We used the ESO/NTT SofI spectrograph to observe proposed IR counterparts to HMXBs, obtaining Ks medium resolution spectra (R = 1320) with a S/N >= 100. We classified them through comparison with publishe…

InfraredAstrophysics::High Energy Astrophysical PhenomenaExtinction (astronomy)FOS: Physical sciencesInfrared spectroscopyAstrophysicsAstrophysicsStellar classificationSpectral line:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Fuentes de Rayos X [UNESCO]UNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Fuentes de Rayos XSpectroscopySpectrographAstrophysics::Galaxy AstrophysicsPhysicsAstrophysics (astro-ph)Astronomy and AstrophysicsAccretion accretion disksX-rays : binaries; Stars : supergiants; Accretion accretion disks; Infrared : starsSpace and Planetary Sciencestars [Infrared]binaries [X-rays]UNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::EstrellasSupergiantsupergiants [Stars]:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Estrellas [UNESCO]Astronomy & Astrophysics
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Polymorphisms in endothelin system genes, arsenic levels and obesity risk.

2015

Background/objectivesObesity has been linked to morbidity and mortality through increased risk for many chronic diseases. Endothelin (EDN) system has been related to endothelial function but it can be involved in lipid metabolism regulation: Receptor type A (EDNRA) activates lipolysis in adipocytes, the two endothelin receptors mediate arsenic-stimulated adipocyte dysfunction, and endothelin system can regulate adiposity by modulating adiponectin activity in different situations and, therefore, influence obesity development. The aim of the present study was to analyze if single nucleotide polymorphisms (SNPs) in the EDN system could be associated with human obesity.Subjects/methodsWe analyz…

MaleEspañaObesidad:Analytical Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Physical Examination::Body Constitution::Body Weights and Measures::Body Fat Distribution::Adiposity [Medical Subject Headings]Endothelins:Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::Humans [Medical Subject Headings]:Chemicals and Drugs::Biological Factors::Intercellular Signaling Peptides and Proteins::Endothelins [Medical Subject Headings]Polymorphism (computer science)Risk Factors:Analytical Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Physical Examination::Body Constitution::Body Weights and Measures::Body Size::Body Weight::Overweight::Obesity [Medical Subject Headings]:Chemicals and Drugs::Inorganic Chemicals::Elements::Arsenic [Medical Subject Headings]:Geographicals::Geographic Locations::Europe::Spain [Medical Subject Headings]education.field_of_studyMultidisciplinary:Diseases::Pathological Conditions Signs and Symptoms::Pathologic Processes::Disease Attributes::Chronic Disease [Medical Subject Headings]Genètica humanaEndothelinsQRMiddle AgedPrognosisReceptor Endothelin APolimorfismo de nucleótido único:Anatomy::Cells::Connective Tissue Cells::Adipocytes [Medical Subject Headings]ObesitatMedicineFemaleTomografía computarizada por rayos X:Phenomena and Processes::Genetic Phenomena::Genotype [Medical Subject Headings]Endothelin receptor:Analytical Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Diagnostic Imaging::Image Interpretation Computer-Assisted::Tomography X-Ray Computed [Medical Subject Headings]Research Articlemedicine.hormonemedicine.medical_specialtyGenotype:Phenomena and Processes::Mathematical Concepts::Probability::Risk [Medical Subject Headings]SciencePopulationSingle-nucleotide polymorphism:Phenomena and Processes::Metabolic Phenomena::Metabolism::Lipid Metabolism::Lipolysis [Medical Subject Headings]BiologyPolymorphism Single NucleotideArsenicReceptores de endotelinasInternal medicineAdipocitos:Chemicals and Drugs::Amino Acids Peptides and Proteins::Proteins::Membrane Proteins::Receptors Cell Surface::Receptors Peptide::Receptors Endothelin [Medical Subject Headings]medicineHumansGenetic Predisposition to DiseaseObesityeducation:Phenomena and Processes::Genetic Phenomena::Genetic Variation::Polymorphism Genetic::Polymorphism Single Nucleotide [Medical Subject Headings]AdiponectinHaplotypeEnfermedad crónicamedicine.diseaseObesityEndocrinologyHaplotypesSpain:Chemicals and Drugs::Biological Factors::Intercellular Signaling Peptides and Proteins::Adipokines::Adiponectin [Medical Subject Headings]GenotipoFollow-Up StudiesArsénicoPLoS ONE
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Structural and Vibrational Properties of Corundum-type In2O3 Nanocrystals under Compression

2017

[EN] This work reports the structural and vibrational properties of nanocrystals of corundum-type In2O3 (rh-In2O3) at high pressures by using angle-dispersive x-ray diffraction and Raman scattering measurements up to 30 GPa. The equation of state and the pressure dependence of the Raman-active modes of the corundum phase in nanocrystals are in good agreement with previous studies on bulk material and theoretical simulations on bulk rh-In2O3. Nanocrystalline rh-In2O3 showed stability under compression at least up to 20 GPa, unlike bulk rh-In2O3 which gradually transforms to the orthorhombic Pbca (Rh2O3-III-type) structure above 12 14 GPa. The different stability range found in nanocrystallin…

Materials scienceCorundum nanocrystalsThermodynamicsBioengineeringCorundumNanotechnology02 engineering and technologyengineering.material010402 general chemistryEspectroscopia01 natural sciencesIndium oxidesymbols.namesakePhase (matter)NanocristalesGeneral Materials ScienceElectrical and Electronic EngineeringhighpressureMechanical EngineeringDifracción de rayos XGeneral Chemistry021001 nanoscience & nanotechnologyNanocrystalline material0104 chemical sciencesX-ray diffractionNanocrystalMechanics of MaterialsFISICA APLICADAX-ray crystallographyRaman spectroscopysymbolsengineeringOrthorhombic crystal systemAb initio calculations0210 nano-technologyRaman spectroscopyRaman scatteringAlta presión
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Airways cephalometric norms from a sample of Caucasian Children

2021

Background: The diagnosis of the respiratory pattern and the analysis of airway dimension using lateral cephalometric radiographs include the study of the adenoid region, free air space of the nasopharynx and oropharynx, soft palate and posterior part of the tongue. The objective of this study is to identify the airways cephalometric norms from a sample of Caucasian children, in relation to gender, age and type of malocclusion. Material and Methods: A total of 480 patients of both sexes were included in the study, the age ranged between 6-12 years. The radiographic records were analyzed using the Nemoceph® 11.3.0 software and the diagnosis of skeletal class was performed using the Steiner a…

OrthodonticsSoft palatebusiness.industryRadiographyCefalometríaPediatríaRayos XOdontologíaOrthodonticsReviewrespiratory systemCraniometryAdenoidmedicine.diseaseDesarrollo infantilmedicine.anatomical_structureTonguemedicineMalocclusionRespiratory systembusinessAirwayGeneral DentistryUNESCO:CIENCIAS MÉDICASJournal of Clinical and Experimental Dentistry
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Environment recognition applied to particle detectors

2017

Resumen en español Introducción Los detectores de partículas son dispositivos que registran la radiación ionizante, bien de sistemas activos (rayos X, aceleradores, etc.) o bien de isótopos radiactivos. Para poder realizar medidas de precisión con estos instrumentos, es necesario modelar geométricamente el entorno, contorno o escena bajo estudio. Estas condiciones geométricas se pueden determinar de forma más o menos precisa en algunos experimentos de física de partículas/nuclear, y en algunos sistemas de imagen, como las tomografías. Sin embargo, este escenario no es necesariamente el habitual. El propósito principal de este trabajo de tesis es desarrollar técnicas e instrumentos que aport…

UNESCO::FÍSICA::Electromagnetismo ::Rayos X:FÍSICA::Electromagnetismo ::Rayos X [UNESCO]:FÍSICA::Óptica ::Radiación visible [UNESCO]Detectores de radiaciónUNESCO::MATEMÁTICAS::Geometría::Geometría proyectivaUNESCO::FÍSICA::Óptica ::Radiación visibleInformación de contorno:MATEMÁTICAS::Geometría::Geometría proyectiva [UNESCO]
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