Search results for " Detector"

showing 10 items of 2719 documents

Determination of alcohols in essential oils by liquid chromatography with ultraviolet detection after chromogenic derivatization

2013

Abstract An HPLC-UV method to determine compounds having a hydroxyl functional group in plant essential oils is developed. The sample is diluted with 1,4-dioxane and the analytes are derivatized with phthalic anhydride. The derivatives (phthalates hemiesters) are separated on a C8 column using an acetonitrile (ACN)/water gradient. Separation conditions were optimized using the DryLab® method development software. For the alcohols and phenols present in mint and rose essential oils, optimization led to a ca. 40 min gradient time and a column temperature of 8 °C. The alcohol and its derivatives were identified using HPLC with mass spectrometry (MS) detection. A large sensitivity enhancement w…

AlcoholRosaMass spectrometryBiochemistryHigh-performance liquid chromatographyAnalytical Chemistrylaw.inventionchemistry.chemical_compoundLimit of DetectionlawOils VolatileFlame ionization detectorPhenolsDerivatizationDetection limitPhthalic anhydrideChromatographyOrganic ChemistryTemperatureReproducibility of ResultsGeneral MedicinechemistryAlcoholsPhthalic AnhydridesSpectrophotometry UltravioletChromatography LiquidMenthaJournal of Chromatography A
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Search for neutral MSSM Higgs bosons at LEP

2006

The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four collaborations are statistically combined and examined for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number of "benchmark" models, including CP-conserving and CP-violating scenarios. Thes…

AlephPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; ALEPH; DELPHI; L3; OPALPhysics and Astronomy (miscellaneous)Parameter space01 natural sciencesOPAL DETECTORHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Event (probability theory)BosonPhysicsEXPLICIT CP VIOLATIONROOT-S=189 GEVOPALFLAVOR INDEPENDENT SEARCHParticle physics - ExperimentPhysicsSettore FIS/01 - Fisica SperimentaleHiggs particle. search forSUPERGAUGE TRANSFORMATIONSALEPHLARGE ELECTRON POSITRON COLLIDERALEPH DELPHI L3 OPALSUPERSYMMETRIC STANDARD MODELROOT-SL3Higgs bosonPARTICLE PHYSICSParticle physicselectron positron. colliding beamselectron positron. annihilationFOS: Physical sciencessupersymmetric standard model;; explicit cp violation;; electric-dipole moment;; e(+)e(-) collisions;; root-s=189 gev;; opal detector;; root-s;; z(0) decays;; supergauge transformations;; radiative-correctionsHiggs particle. electroproductionddc:500.2-SUPERSYMMETRIC STANDARD MODEL; EXPLICIT CP VIOLATION; FLAVOR INDEPENDENT SEARCH; ELECTRIC-DIPOLE MOMENT; E(+)E(-) COLLISIONS; ROOT-S; ROOT-S=189 GEV; OPAL DETECTOR; Z(0) DECAYS; SUPERGAUGE TRANSFORMATIONSHiggs particleLEP colliderNext-to-Minimal Supersymmetric Standard ModelELECTRIC-DIPOLE MOMENTE(+)E(-) COLLISIONSConsistency (statistics)0103 physical sciencesddc:530High Energy Physics010306 general physicsEngineering (miscellaneous)DELPHIelectron positron010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHiggs BosonLEPHIGGSHiggs boson standard modelZ(0) DECAYSExperimental High Energy PhysicsHigh Energy Physics::ExperimentHiggs Boson; LEP colliderMSSMMinimal Supersymmetric Standard ModelHiggs
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Studies of Quantum Chromodynamics with the ALEPH Detector

1998

Previously published and as vet unpublished QCD results obtained with the ALEPH detector at LEP1 are presented. The unprecedented statistics allows detailed studies of both perturbative and non-perturbative aspects of strong interactions to be carried out using hadronic Z and tau decays. The studies presented include precise determinations of the strong coupling constant. tests of its flavour independence, tests of the SU(3) gauge structure of QCD, study of coherence effects, and measurements of single-particle inclusive distributions and two-particle correlations for many identified baryons and mesons. (C) 1998 Elsevier Science B.V.

AlephParticle physicsMesonHigh Energy Physics::LatticeElectron–positron annihilationHadronAleph; LEP; QCD; Quantum Chromo DynamicsGeneral Physics and Astronomy01 natural sciencesNuclear physicsQuantum Chromo Dynamics0103 physical sciencesBibliography010306 general physicsPhysicsQuantum chromodynamics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyLEPBose–Einstein correlationsQCDALEPH detectorBaryonHigh Energy Physics::ExperimentAlephParticle Physics - Experiment
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H-Point Curve Isolation Method for Coupled Liquid Chromatography and UV−Visible Spectrophotometry

2000

The H-point curve isolation method (HPCIM) for the detection of unknown interferences in chromatography is proposed. The method allows one to estimate the UV-vis spectra of interfering species in a sample as well as to test the purity of the chromatographic peaks. Besides the detection of the unknown interferences in a sample, this method allows one to calculate the concentration of an analyte in the presence of unknown compounds. To illustrate the reliability of the proposed method, samples of diuretics and amphetamines have been analyzed by normal- and reversed-phase high-performance chromatography.

AnalyteChromatographymedicine.diagnostic_testChemistryAmphetaminesAnalytical chemistryAnalytical ChemistryChromatography detectorSpectrophotometrymedicineSpectrophotometry UltravioletDiureticsChromatography columnChromatography LiquidAnalytical Chemistry
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Electrochemical pH Control at Gold Nanowires

2018

In this work, interdigitated arrays of nanowire electrodes are used with one array acting as the working electrode while the other is used to generate the required protons. Finite element simulations of the pH control electrodes were performed to provide insight on the generation and subsequent diffusion of protons. This informed the inter-tine spacing of the electrodes used.. This electrochemical pH control method was then used to enable the detection of analytes of interest.

AnalyteWorking electrodeMaterials sciencePhysics::Instrumentation and Detectorsbusiness.industry020209 energy010401 analytical chemistryPh controlNanowire02 engineering and technologypH control gold nanowire heavy metal in situ simulationElectrochemistry01 natural sciencesFinite element method0104 chemical sciencesSettore ING-IND/23 - Chimica Fisica ApplicataPhysics::Plasma PhysicsElectrode0202 electrical engineering electronic engineering information engineeringOptoelectronicsDiffusion (business)business2018 IEEE 18th International Conference on Nanotechnology (IEEE-NANO)
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A study of the effect of molecular and aerosol conditions in the atmosphere on air fluorescence measurements at the Pierre Auger Observatory

2010

The air fluorescence detector of the Pierre Auger Observatory is designed to perforin calorimetric measurements of extensive air showers created by Cosmic rays of above 10(18) eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group Of monitoring instruments to record atmospheric conditions across the detector site, ail area exceeding 3000 km(2). The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierr…

Angstrom exponentAstronomyAstrophysics01 natural sciencesAugerCROSS-SECTIONSCOSMIC-RAY SHOWERSObservatoryDEPENDENCEHigh-Energy Cosmic Ray010303 astronomy & astrophysicsPhysicsHigh Energy Astrophysical Phenomena (astro-ph.HE)Lidar[SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]ANGSTROM EXPONENTPierre Auger ObservatoryBi-static lidarELECTRONSComputingMethodologies_DOCUMENTANDTEXTPROCESSINGMULTIPLE-SCATTERINGLight emissionFísica nuclearAstrophysics - Instrumentation and Methods for AstrophysicsAstrophysics - High Energy Astrophysical PhenomenaLIGHT-EMISSIONAstrophysics - Cosmology and Nongalactic Astrophysics[PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]Cosmology and Nongalactic Astrophysics (astro-ph.CO)Extensive air showerFOS: Physical sciencesCosmic raySURFACE DETECTORAir fluorescence method0103 physical sciencesExtensive air showersRECONSTRUCTIONAerosolInstrumentation and Methods for Astrophysics (astro-ph.IM)Cosmic raysPierre Auger ObservatoryAerosolsCalorimeter (particle physics)Atmospheric effect010308 nuclear & particles physicsAtmosphereFísicaAstronomy and AstrophysicsCosmic rays; Extensive air showers; Air fluorescence method; Atmosphere; Aerosols; Lidar; Bi-static lidarCosmic rayNITROGENAir showerFluorescence Telescopes13. Climate actionExperimental High Energy PhysicsAEROSSOL
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The IceCube prototype string in Amanda

2006

The Antarctic Muon And Neutrino Detector Array (Amanda) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electrons. IceCube is a cubic-kilometer-sized expansion of Amanda currently being built at the South Pole. In IceCube the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new all-digital technology was deployed in the Amanda array in the year 2000. In this paper we describe the technology and demonst…

Antarctic Muon And Neutrino Detector ArrayAstroparticle physicsPhysicsNuclear and High Energy PhysicsPhotomultiplierPhotonMuonPhysics::Instrumentation and DetectorsAstrophysics::High Energy Astrophysical PhenomenaAstrophysics (astro-ph)Neutrino telescopeAstrophysics::Instrumentation and Methods for AstrophysicsFOS: Physical sciencesAstronomyAstrophysicsNeutrino telescopeAmandaIceCubeData acquisitionSignal digitizationAmanda; IceCube; Neutrino telescope; Signal digitizationInstrumentationCherenkov radiation
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Muon track reconstruction and data selection techniques in AMANDA

2004

The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500m and 2000m. The primary goal of this detector is to discover astrophysical sources of high energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of r…

Antarctic Muon And Neutrino Detector ArrayPhysicsAMANDANuclear and High Energy PhysicsParticle physicsAMANDA; Neutrino astrophysics; Neutrino telescope; Track reconstructionMuonPhysics::Instrumentation and DetectorsAstrophysics::High Energy Astrophysical PhenomenaAstrophysics (astro-ph)DetectorFOS: Physical sciencesAstrophysicsNeutrino telescopeTrack reconstructionNeutrino astrophysicsIceCube Neutrino ObservatoryNeutrino detectorHigh Energy Physics::ExperimentMuon neutrinoNeutrinoAstrophysics - Instrumentation and Methods for AstrophysicsInstrumentation and Methods for Astrophysics (astro-ph.IM)InstrumentationLeptonNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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Calibration and survey of AMANDA with the SPASE detectors

2004

We report on the analysis of air showers observed in coincidence by the Antarctic Muon and Neutrino detector array (AMANDA-B10) and the South Pole Air Shower Experiment (SPASE-1 and SPASE-2). We discuss the use of coincident events for calibration and survey of the deep AMANDA detector as well as the response of AMANDA to muon bundles. This analysis uses data taken during 1997 when both SPASE-1 and SPASE-2 were in operation to provide a stereo view of AMANDA. © 2003 Elsevier B.V. All rights reserved.

Antarctic Muon And Neutrino Detector ArrayPhysicsNuclear and High Energy PhysicsMuonDetectorAstronomyCosmic rayParticle detectorAir showerNeutrino detectorCosmic rays; Neutrino telescopesCoincidentNeutrino telescopesCosmic raysInstrumentationNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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The search for Muon neutrinos from northern hemisphere gamma-ray bursts with AMANDA

2007

We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the Northern Hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. Based on our observations of zero neutrinos during and immediately prior to the GRBs in the dataset, we set the most stringent upper limit on muon neutrino emission correlated with gamma-ray bursts. Assuming a Waxman-Bahcall spectrum and incorporating all systematic uncertainties, our flux upper limit has a normalizatio…

Antarctic Muon And Neutrino Detector ArrayPhysics::Instrumentation and DetectorsAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesFluxAstrophysicsAstrophysics01 natural sciencesGamma rays: bursts; Neutrinos0103 physical sciencesMuon neutrinoNeutrinos010306 general physics010303 astronomy & astrophysicsPhysicsGamma rays: burstsMuonAstrophysics (astro-ph)Order (ring theory)Astronomy and AstrophysicsSpace and Planetary ScienceAstronomiaHigh Energy Physics::ExperimentNeutrinoGamma-ray burstEnergy (signal processing)
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