Search results for "IQ"

showing 10 items of 21401 documents

Catalytic enantioselective aza-Reformatsky reaction with seven-membered cyclic imines dibenzo[b,f][1,4]oxazepines

2017

A catalytic enantioselective aza-Reformatsky reaction is reported with cyclic dibenzo[b,f][1,4]oxazepines and ethyl iodoacetate leading to the synthesis of chiral ethyl 2-(10,11-dihydrodibenzo[b,f][1,4]oxazepin-11-yl)acetate derivatives with excellent yields and high enantioselectivities (up to 98% yield and 97 : 3 er) using a readily available diaryl prolinol L4 as the chiral ligand and Me2Zn as the zinc source under an air atmosphere. Furthermore, different transformations were carried out with the corresponding chiral β-amino esters, preserving in all cases the optical purity.

010405 organic chemistryStereochemistryOrganic ChemistryEthyl iodoacetateChiral ligandEnantioselective synthesis010402 general chemistry01 natural sciences0104 chemical sciencesCatalysisProlinolReaccions químiqueschemistry.chemical_compoundchemistryYield (chemistry)Reformatsky reactionEnantiomeric excessQuímica orgànica
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Analysis of psychoactive substances in water by information dependent acquisition on a hybrid quadrupole time-of-flight mass spectrometer.

2016

Emerging drugs of abuse, belonging to many different chemical classes, are attracting users with promises of “legal” highs and easy access via internet. Prevalence of their consumption and abuse through wastewater-based epidemiology can only be realized if a suitable analytical screening procedure exists to detect and quantify them in water. Solid-phase extraction and ultra-high performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UHPLC–QqTOF–MS/MS) was applied for rapid suspect screening as well as for the quantitative determination of 42 illicit drugs and metabolites in water. Using this platform, we were able to identify amphetamines, tryptamines, piperazines, p…

010501 environmental sciencesWastewaterMass spectrometryTandem mass spectrometry01 natural sciencesBiochemistryRiver waterHigh resolution mass spectrometryAnalytical ChemistryRiversTandem Mass SpectrometryQuantificationPsychoactive drugsHumansSample preparationSolid phase extractionQuadrupole time of flightChromatography High Pressure Liquid0105 earth and related environmental sciencesPsychotropic DrugsChromatographyChemistryIllicit Drugs010401 analytical chemistryOrganic ChemistrySolid Phase ExtractionWaterGeneral MedicineQuantitative determination0104 chemical sciencesWastewaterEnvironmental chemistryScreeningDatabases ChemicalWater Pollutants ChemicalJournal of chromatography. A
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Measuring rill erosion using structure from motion: A plot experiment

2017

Abstract In this paper the results of a plot experiment on rill erosion are reported. The rill network, manually incised on the soil and further shaped by a clear inflow discharge, was surveyed using the three-dimensional photo-reconstruction (3D-PR) technique which allows to obtain a digital terrain model (DTM) by a large series of oblique images of the channel from consumer un-calibrated and non-metric cameras. The three-dimensional (3D) DTM and the quasi-tridimensional (2.5D) model were generated by Agisoft Photoscan software. For a single rill channel, the reliability of the 3D image-based ground measurements of morphological and hydraulic variables was positively tested by the correspo…

010504 meteorology & atmospheric sciences0208 environmental biotechnologyFlow (psychology)02 engineering and technologyInflow01 natural sciencesSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliDigital elevation modelGeomorphology0105 earth and related environmental sciencesEarth-Surface ProcessesRill erosiongeographygeography.geographical_feature_categoryRill characteristicDEMSedimentChannelizedField experiment020801 environmental engineeringRillErosion3D Photo-reconstructionImage-based ground measurement techniqueProfilometerGeologyCATENA
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The WISE 2000 and 2001 Field Experiments in Support of the SMOS Mission:Sea Surface L-Band Brightness Temperature Observations and Their Application …

2004

Camps, Adriano ... et al.-- 20 pages, 16 figures, 3 tables

010504 meteorology & atmospheric sciences0211 other engineering and technologiesWind02 engineering and technologySea stateAtmospheric sciences01 natural sciencesOceanographic techniquesWind waveSurface roughnessEmissivitySeawater14. Life underwaterElectrical and Electronic EngineeringRadiometry[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensingPhysics[SDU.OCEAN]Sciences of the Universe [physics]/Ocean AtmosphereRadiometerFoamsOcean wavesRemote sensingSea surface temperature13. Climate actionBrightness temperatureGeneral Earth and Planetary SciencesSMOS MissionSignificant wave height
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Associations between air pollution and pediatric eczema, rhinoconjunctivitis and asthma: A meta-analysis of European birth cohorts

2020

Background: Uncertainly continues to exist regarding the role of air pollution on pediatric asthma and allergic conditions, especially as air pollution levels have started to decrease in recent decades. Objective: We examined associations of long-term air pollution levels at the home address with pediatric eczema, rhinoconjunctivitis and asthma prevalences in five birth cohorts (BIB, EDEN, GASPII, RHEA and INMA) from seven areas in five European countries. Methods: Current eczema, rhinoconjunctivitis and asthma were assessed in children aged four (N = 6527) and eight years (N = 2489). A multi-morbidity outcome (≥2 conditions versus none) was also defined. Individual outdoor levels of nitrog…

010504 meteorology & atmospheric sciencesAir pollution exposureAir pollutionEczemacross-sectional studies010501 environmental sciencesmedicine.disease_cause01 natural sciences[SDV.MHEP.PSR]Life Sciences [q-bio]/Human health and pathology/Pulmonology and respiratory tractRhinoconjunctivitisEnvironmental healthAir PollutionmedicineAir Pollutants/toxicityHumans[SDV.IMM.ALL]Life Sciences [q-bio]/Immunology/AllergologyAdverse effectChildlcsh:Environmental sciences0105 earth and related environmental sciencesGeneral Environmental ScienceAsthmaRhinitislcsh:GE1-350Pediatric[SDV.EE.SANT]Life Sciences [q-bio]/Ecology environment/Health[SDV.MHEP.PED]Life Sciences [q-bio]/Human health and pathology/PediatricsAir PollutantsOdds ratioEnvironmental Exposuremedicine.diseaseConjunctivitisConfidence intervalAsthma3. Good healthEurope13. Climate actionMeta-analysis[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologieParticulate MatterConjunctivitis/epidemiologyBirth cohortEnvironmental SciencesBirth cohort
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Fractals and geography

2007

010504 meteorology & atmospheric sciencesAnthropology[SHS.GEO] Humanities and Social Sciences/Geography0211 other engineering and technologies021107 urban & regional planning02 engineering and technology[SHS.GEO]Humanities and Social Sciences/Geography01 natural sciences[ SHS.GEO ] Humanities and Social Sciences/GeographyGeographyCartographymodèles mathématiquesanalyse spatiale0105 earth and related environmental sciences
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Reply to 'Limited Late Antique cooling'

2017

010504 meteorology & atmospheric sciencesAntiqueGeneral Earth and Planetary SciencesAncient history010502 geochemistry & geophysics01 natural sciences0105 earth and related environmental sciencesNature Geoscience
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Neocomian to early Aptian syn-rift evolution of the normal to oblique-rifted North Gabon Margin (Interior and N'Komi Basins).

2009

18 pages; International audience; The North Gabon coastal rift basins consist of a set of 130–150 long-segment asymmetrically tilted half grabens (Interior Basin) and 000–020 short-segment en échelon half grabens (N'Komi Basin) separated by 040–060 major transverse faults. Tectono-sedimentary analysis of field and subsurface data reveals the control exerted by extensional tectonism over continental sedimentation. During Berriasian to early Barremian times, uniform uniaxial 040–060 extension was responsible for the stretching of the brittle upper crust over a 100-km wide domain. During late Barremian–early Aptian times, the main locus of extension stepped westward resulting in severe end-rif…

010504 meteorology & atmospheric sciencesAptianStratigraphy[SDE.MCG]Environmental Sciences/Global ChangesEarly CretaceousEnd-rift erosionStructural basin010502 geochemistry & geophysicsOceanography[ SDU.STU.ST ] Sciences of the Universe [physics]/Earth Sciences/Stratigraphy01 natural sciencesPaleontologyEchelon formationGabon0105 earth and related environmental sciences[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/TectonicsRift segmentationRiftOblique riftingGeologyCrust[ SDU.STU.TE ] Sciences of the Universe [physics]/Earth Sciences/TectonicsCretaceousGrabenTectonics[ SDE.MCG ] Environmental Sciences/Global ChangesGeophysics[SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/StratigraphyEconomic GeologyPrecambrian heritageNormal riftingGeology
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A Search for Ultra-high-energy Neutrinos from TXS 0506+056 Using the Pierre Auger Observatory

2020

Results of a search for ultra-high-energy neutrinos with the Pierre Auger Observatory from the direction of the blazar TXS 0506+056 are presented. They were obtained as part of the follow-up that stemmed from the detection of high-energy neutrinos and gamma rays with IceCube, Fermi-LAT, MAGIC, and other detectors of electromagnetic radiation in several bands. The Pierre Auger Observatory is sensitive to neutrinos in the energy range from 100 PeV to 100 EeV and in the zenith-angle range from θ = 60° to θ = 95°, where the zenith angle is measured from the vertical direction. No neutrinos from the direction of TXS 0506+056 have been found. The results were analyzed in three periods: One of 6 m…

010504 meteorology & atmospheric sciencesAstronomyAstrophysicspower spectrum7. Clean energy01 natural sciencesIceCubeObservatoryMAGIC (telescope)UHE Cosmic Rays010303 astronomy & astrophysicsHigh energy astrophysics Neutrino astrony Blazars Transient sources Active galaxiesHigh Energy Astrophysical Phenomena (astro-ph.HE)Physicsastro-ph.HEOBSERVATÓRIOSAstrophysics::Instrumentation and Methods for Astrophysicsneutrino: UHEUHE [neutrino]AugerobservatoryHigh energy astrophysics; Neutrino astronomy; Blazars; Transient sources; Active galaxiesNeutrino detectorNeutrino astronomyNeutrinoAstrophysics - High Energy Astrophysical PhenomenaHigh energy astrophysicsradiation: electromagneticHigh-energy astronomyAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesGLASTblazar0103 physical sciencesNeutrinoHigh Energy PhysicsZenithAstrophysique0105 earth and related environmental sciencesPierre Auger ObservatoryFísicaAstronomy and AstrophysicsAstronomiesensitivityMAGICTransient sourcesSciences de l'espaceelectromagnetic [radiation]13. Climate actionSpace and Planetary Sciencegamma rayExperimental High Energy PhysicsActive galaxiesddc:520spectralNeutrino astronomy[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]Blazars
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IceCube search for neutrinos coincident with compact binary mergers from LIGO-Virgo's first gravitational-wave transient catalog

2020

Using the IceCube Neutrino Observatory, we search for high-energy neutrino emission coincident with compact binary mergers observed by the LIGO and Virgo gravitational-wave (GW) detectors during their first and second observing runs. We present results from two searches targeting emission coincident with the sky localization of each GW event within a 1000 s time window centered around the reported merger time. One search uses a model-independent unbinned maximum-likelihood analysis, which uses neutrino data from IceCube to search for pointlike neutrino sources consistent with the sky localization of GW events. The other uses the Low-Latency Algorithm for Multi-messenger Astrophysics, which …

010504 meteorology & atmospheric sciencesAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesAstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsBayesian7. Clean energy01 natural sciencesNeutrino astronomy; High energy astrophysics; Gravitational waveslocalizationIceCubeIceCube Neutrino ObservatoryGravitational wavesparticle source [neutrino]0103 physical sciencesLIGO010303 astronomy & astrophysics0105 earth and related environmental sciencesastro-ph.HEHigh Energy Astrophysical Phenomena (astro-ph.HE)PhysicsGravitational wavegravitational radiationAstrophysics::Instrumentation and Methods for AstrophysicsAstronomy and AstrophysicsLIGOobservatorymessengerMassless particleVIRGONeutrino detector13. Climate actionSpace and Planetary ScienceNeutrino astronomycompact [binary]Physique des particules élémentairesddc:520High Energy Physics::ExperimentNeutrino astronomyNeutrinoAstrophysics - High Energy Astrophysical PhenomenaHigh energy astrophysicsLepton
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