Search results for "RV"

showing 10 items of 42095 documents

Electrochemical Fluorocyclization of N-Allylcarboxamides to 2-Oxazolines by Hypervalent Iodine Mediator

2018

A resource saving protocol for the synthesis of 5-fluoromethyl-2-oxazolines by using electrochemistry has been realized. Thereby, a hypervalent iodine species I(III) is generated by anodic oxidation in the presence of Et3N·5HF and mediates the cyclization of N-allylcarboxamide to 5-fluoromethyl-2-oxazoline. This method allows application to various substrates furnishing the 2-oxazolines with yields up to 68%. The protocol is easy to conduct under constant current conditions offering a sustainable alternative over conventional reagent-based pathways.

010405 organic chemistryAnodic oxidationResource savingOrganic ChemistryHypervalent moleculechemistry.chemical_element010402 general chemistryIodineElectrochemistry01 natural sciencesBiochemistryCombinatorial chemistry0104 chemical scienceschemistryReagentPhysical and Theoretical ChemistryOrganic Letters
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Fluorocyclization of N-Propargylamides to Oxazoles by Electrochemically Generated ArIF2

2019

A sustainable synthesis of 5-fluoromethyl-2-oxazoles by use of electrochemistry has been demonstrated. Hypervalent ArIF2 is generated by direct electrochemical oxidation of iodoarene ArI in Et3N·5HF and mediates the fluorocyclization of N-propargylamides to 5-fluoromethyl-2-oxazoles. The stoichiometry in ArI turned out to be a key parameter in controlling the product selectivity. This electrochemical protocol provides access to fluorinated oxazoles starting from simply available N-propargylamides with yields up to 65% and offers a green alternative over conventional reagent-based approaches.

010405 organic chemistryChemistryOrganic ChemistryHypervalent molecule010402 general chemistryElectrochemistry01 natural sciencesBiochemistryCombinatorial chemistry0104 chemical sciencesReagentPhysical and Theoretical ChemistrySelectivityStoichiometryOrganic Letters
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Herbicidal value of essential oils from oregano-like flavour species

2017

ABSTRACTChemical composition and phytotoxicity of oregano, marjoram and Thymus mastichina essential oils against Portulaca oleracea L., Lolium multiflorum Lam. and Echinochloa crus-galli (L.) Beauv. has been investigated. Seventy-seven compounds reaching 97.3% and 99.4% were identified by gas chromatography–mass spectrometry. Carvacrol (60.42 ± 0.07%), p-cymene (15.52 ± 0.02%) and γ-terpinene (5.19 ± 0.02%) were the main compounds in oregano essential oil, whereas large amounts of 1,8-cineol (59.59 ± 0.85%, 49.49 ± 0.37%), linalool (13.05 ± 0.04%, 5.66 ± 0.01%) and α-terpineol (3.36 ± 0.10%, 5.59 ± 0.01%), followed by β-pinene (4.35 ± 0.39, 5.54 ± 0.01%) and α-pinene (4.11 ± 0.53, 4.28 ± 0.…

010405 organic chemistryImmunologyThymus mastichinaLolium multiflorumBiologyPortulacabiology.organism_classification01 natural sciences0104 chemical scienceslaw.invention010404 medicinal & biomolecular chemistrychemistry.chemical_compoundLinaloolchemistrylawGerminationBotanyCarvacrolPhytotoxicityFood scienceAgronomy and Crop ScienceEssential oilFood ScienceFood and Agricultural Immunology
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Viewpoint: Atomic-Scale Design Protocols toward Energy, Electronic, Catalysis, and Sensing Applications

2019

Nanostructured materials are essential building blocks for the fabrication of new devices for energy harvesting/storage, sensing, catalysis, magnetic, and optoelectronic applications. However, because of the increase of technological needs, it is essential to identify new functional materials and improve the properties of existing ones. The objective of this Viewpoint is to examine the state of the art of atomic-scale simulative and experimental protocols aimed to the design of novel functional nanostructured materials, and to present new perspectives in the relative fields. This is the result of the debates of Symposium I "Atomic-scale design protocols towards energy, electronic, catalysis…

010405 organic chemistrySensing applicationsChemistryNanostructured materials: Physics [G04] [Physical chemical mathematical & earth Sciences]Physik (inkl. Astronomie)010402 general chemistry01 natural sciencesAtomic units0104 chemical sciencesInorganic Chemistry: Physique [G04] [Physique chimie mathématiques & sciences de la terre]Systems engineeringMultilayers | Interfaces (materials) | Individual layermaterials theory computational DFT modellingPhysical and Theoretical ChemistryEnergy harvestingEnergy (signal processing)Inorganic Chemistry
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The MIRS computer package for modeling the rovibrational spectra of polyatomic molecules

2003

International audience; The MIRS spectroscopic software for the modeling of ro-vibrational spectra of polyatomic molecules is presented. It is designed for the global treatment of complex band systems of molecules to take full account of symmetry properties. It includes e cient algorithms based on the irreducible tensor formalism. Predictions and simultaneous data fi tting (positions and intensities) are implemented as well as advanced options related to group theory algebra. Illustrative examples on CH3D, CH4, CH3Cl and PH3 are reported and the present status of data available is given. It is written in C++ for standard PC computer operating under Windows. The full package including on-lin…

010504 meteorology & atmospheric sciences01 natural sciencesSpectral lineSoftwareComputer package0103 physical sciencesMoleculeSpectroscopy0105 earth and related environmental sciencesPhysics[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]RadiationSpectroscopic database010304 chemical physicsbusiness.industryPolyatomic ionRotational–vibrational spectroscopyMolecular spectroscopyAtmospheric applicationsAtomic and Molecular Physics and OpticsComputational physics[ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]Rotation vibrationCurve fittingbusinessInfraredGroup theorySoftware
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Dimensionless Stage-Discharge Relationship for a Non-Linear Water Reservoir: Theory and Experiments

2020

In the field of hydrology, stage&ndash

010504 meteorology & atmospheric sciences0207 environmental engineering02 engineering and technologyOceanography01 natural sciencesWater balanceWater reservoirSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-Forestali020701 environmental engineeringlcsh:ScienceWaste Management and Disposal0105 earth and related environmental sciencesEarth-Surface ProcessesWater Science and TechnologyMathematicsConservation of energyMechanicsDischarge coefficientstage-discharge relationshipanalytical solutionNonlinear systemexperimental testContinuity equationlcsh:Qnon-linear reservoirDimensionless quantity
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Budyko’s Based Method for Annual Runoff Characterization across Different Climatic Areas: an Application to United States

2018

Runoff data knowledge is of fundamental importance for a wide range of hydrological, ecological, and socioeconomic applications. The reconstruction of annual runoff is a fundamental task for several activities related to water resources management, especially for ungauged basins. At catchment scales, the Budyko's framework provides an extremely useful and, in some cases, accurate estimation of the long-term partitioning of precipitation into evapotranspiration and runoff as a function of the prevailing climatic conditions. Recently the same long-term partitioning rules have been successfully used to describe water partitioning also at the annual scale and calculate the annual runoff distrib…

010504 meteorology & atmospheric sciences0208 environmental biotechnologyDrainage basin02 engineering and technologyStructural basinWater resources assessment01 natural sciencesBudyko's curveEvapotranspirationRange (statistics)Precipitation0105 earth and related environmental sciencesWater Science and TechnologyCivil and Structural EngineeringSubdivisionHydrologygeographygeography.geographical_feature_categorybusiness.industrySettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaMOPEX data020801 environmental engineeringWater resourcesEnvironmental scienceAnnual water balanceAnnual runoff distributionSurface runoffbusiness
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Curve Numbers Seasonal Variation in Mid-Mediterranean Area

2018

AbstractThe curve number (CN) method is a popular technique for estimating a rainstorm event’s direct runoff (Q from its storm depth P). It relies on the parameter CN, a lumped expression of a wate...

010504 meteorology & atmospheric sciences0208 environmental biotechnologyStorm02 engineering and technologyRunoff curve numberSeasonalityAtmospheric sciencesmedicine.disease01 natural sciencesAgricultural and Biological Sciences (miscellaneous)020801 environmental engineeringmedicineMediterranean areaEnvironmental scienceSurface runoff0105 earth and related environmental sciencesWater Science and TechnologyCivil and Structural EngineeringEvent (probability theory)Journal of Irrigation and Drainage Engineering
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Geographic and temporal variations in turbulent heat loss from lakes : A global analysis across 45 lakes

2018

Heat fluxes at the lake surface play an integral part in determining the energy budget and thermal structure in lakes, including regulating how lakes respond to climate change. We explore patterns in turbulent heat fluxes, which vary across temporal and spatial scales, using in situ high-frequency monitoring data from 45 glob- ally distributed lakes. Our analysis demonstrates that some of the lakes studied follow a marked seasonal cycle in their turbulent surface fluxes and that turbulent heat loss is highest in larger lakes and those situated at low latitude. The Bowen ratio, which is the ratio of mean sensible to mean latent heat fluxes, is smaller at low lati- tudes and, in turn, the rel…

010504 meteorology & atmospheric sciences0208 environmental biotechnologyta1172ta1171Climate change02 engineering and technologyAquatic ScienceOceanographyAtmospheric sciences01 natural sciencesjärvetLatitudeWater balanceheat fluxesLatent heatparasitic diseaseslakesBowen ratioturbulent heat loss0105 earth and related environmental sciencesthermal structurelake surface15. Life on landilmastonmuutoksetEnergy budget020801 environmental engineeringclimate change13. Climate actionHeat transferarticlesEnvironmental scienceSpatial variabilitylämpötilaenergy budgetlämpöhäviöLimnology and Oceanography
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Who's better at spotting? A comparison between aerial photography and observer-based methods to monitor floating marine litter and marine mega-fauna.

2020

Pollution by marine litter is raising major concerns due to its potential impact on marine biodiversity and, above all, on endangered mega-fauna species, such as cetaceans and sea turtles. The density and distribution of marine litter and mega-fauna have been traditionally monitored through observer-based methods, yet the advent of new technologies has introduced aerial photography as an alternative monitoring method. However, to integrate results produced by different monitoring techniques and consider the photographic method a viable alternative, this ‘new’ methodology must be validated. This study aims to compare observations obtained from the concurrent application of observer-based and…

010504 meteorology & atmospheric sciencesAerial surveyHealth Toxicology and MutagenesisEndangered speciesMarine pollution010501 environmental sciencesToxicology01 natural sciencesAerial surveysMarine pollutionMediterranean seaAerial photographyMarine debrisMediterranean SeaPhotographyAnimalsMarine vertebratesTransect0105 earth and related environmental sciencesRemote sensingWaste ProductsGeneral MedicineRemote sensingPollutionTurtlesSeabirdsMediterranean seaRemote Sensing TechnologyLitterEnvironmental scienceCetaceaPlasticsEnvironmental MonitoringEnvironmental pollution (Barking, Essex : 1987)
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