Search results for "Light irradiation"

showing 10 items of 21 documents

Photoswitching of the antiferromagnetic coupling in an oxamato-based dicopper(ii) anthracenophane

2011

Thermally reversible photomagnetic (ON/OFF) switching behavior has been observed in a dinuclear oxamatocopper(ii) anthracenophane upon UV light irradiation and heating; the two CuII ions (SCu = 1/2) that are antiferromagnetically coupled in the dicopper(ii) metallacyclic precursor (ON state) become uncoupled in the corresponding [4+4] photocycloaddition product (OFF state), as substantiated from both experimental and theoretical studies. © 2011 The Royal Society of Chemistry.

010405 organic chemistryChemistryMetals and AlloysLight irradiation[CHIM.MATE]Chemical Sciences/Material chemistryGeneral Chemistry010402 general chemistryPhotochemistry01 natural sciencesCatalysisAntiferromagnetic coupling0104 chemical sciences3. Good healthSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsIonCrystallographyMaterials ChemistryCeramics and CompositesChemical Communications
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Turning lipophilic phthalocyanines/TiO2 composites into efficient photocatalysts for the conversion of CO2 into formic acid under UV–vis light irradi…

2014

Metal-free, Cu(II)- or Zn(II) tetrakis [4-(2,4-bis-(1,1-dimethylpropyl)phenoxy)]phthalocyanines loaded over TiO2 (anatase) proved to be active in the photoreduction of CO2 to formic acid (HCO2H) in water under UV-vis light. CuPc/TiO2 is catalyst of choice, allowing to reach a maximum yield of HCO2H, unequalled by any other similar catalytic systems. Because of their low environmental impact, low potential cost, and efficient power conversion, these multipurpose materials show promise in the setup of sustainable methods for CO2 valorization. (C) 2014 Elsevier B.V. All rights reserved.

AnataseChemistryFormic acidPhthalocyaninesProcess Chemistry and TechnologyPhthalocyanineLight irradiationPhotochemistryMetallo phthalocyaninesHeterogeneous photocatalysiCatalysisCatalysisHeterogeneous photocatalysischemistry.chemical_compoundUltraviolet visible spectroscopyYield (chemistry)TiO2Settore CHIM/07 - Fondamenti Chimici Delle TecnologieCO2 photo-reductionMetallo phthalocyanineApplied Catalysis A: General
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New polymorph of InVO4: A high-pressure structure with six-coordinated vanadium

2013

A new wolframite-type polymorph of InVO4 is identified under compression near 7 GPa by in situ high-pressure (HP) X-ray diffraction (XRD) and Raman spectroscopic investigations on the stable orthorhombic InVO4. The structural transition is accompanied by a large volume collapse (Delta V/V = -14%) and a drastic increase in bulk modulus (from 69 to 168 GPa). Both techniques also show the existence of a third phase coexisting with the low- and high-pressure phases in a limited pressure range close to the transition pressure. XRD studies revealed a highly anisotropic compression in orthorhombic InVO4. In addition, the compressibility becomes nonlinear in the HP polymorph. The volume collapse in…

DiffractionVanadiumchemistry.chemical_elementOrtho-vanadatesInorganic Chemistrysymbols.namesakeThird phaseVisible-light irradiationFormsPhysical and Theoretical ChemistrySpectroscopySpectroscopyBulk modulusCRYSTALChemistryCRVO4TIVO4CrystallographyPhaseFISICA APLICADATransitionCompressibilitysymbolsOrthorhombic crystal systemRaman spectroscopyDiffraction
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Spin Crossover Systems

2015

Abstract This account constitutes a basic introduction to spin crossover phenomena that is mostly encountered for iron(II) coordination complexes. After briefly describing the occurrence of spin transition in liquid and solid states, the effects of pressure and light irradiation are discussed. Applications and recent trends of this expanding field are also presented.

EngineeringCondensed matter physicsField (physics)business.industrySpin crossoverSpin transitionElectrical engineeringLight irradiationbusiness
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GaP/TiO2 Composite Photocatalyst for CO2 Reduction in Gas-Solid Regime under Simulated Solar Light Irradiation

2014

GaP/TiO2 PhotocatalystCO2 Reduction Solar Light IrradiationSettore CHIM/07 - Fondamenti Chimici Delle Tecnologie
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Photochemical genotoxicity: principles and test methods

2004

In recent years, assessing the photogenotoxic potential of a compound became an issue for certain drugs and cosmetical products. Therefore, existing methods performed according to international guidelines (e.g. OECD guidelines) were adapted to the use of concurrent UV-visible (UV-Vis) light irradiation for the assessment of photomutagenicity/photogenotoxicity. In this review, photobiological bases of the processes occurring in the cell after irradiation with UV- and/or visible (vis)-light as well as a compilation of testing methods is presented. Methods comprise cell free investigations on naked DNA and in vitro methods, such as the photo-Ames test, the photo-HPRT/photo-mouse lymphoma assay…

Geneticsmedicine.medical_specialtyTask forceHealth Toxicology and MutagenesisLight irradiationCell freeBiologymedicine.disease_causeTest (assessment)GeneticsmedicineInternational literatureMedical physicsMutagenicity TestGenotoxicityMutation Research/Reviews in Mutation Research
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Optical Gating of Photosensitive Synthetic Ion Channels

2011

4-oxo-4-(pyren-4-ylmethoxy) butanoic acid is used as a photolabile protecting group to show the optical gating of nanofluidic devices based on synthetic ion channels. The inner surface of the channels is decorated with monolayers of photolabile hydrophobic molecules that can be removed by irradiation, which leads to the generation of hydrophilic groups. This process can be exploited in the UV-light-triggered permselective transport of ionic species in aqueous solution through the channels. The optical gating of a single conical nanochannel and multichannel polymeric membranes is characterised experimentally and theoretically by means of current-voltage and selective permeation measurements,…

Hydrophilic groupsMaterials scienceSynthetic ion channelsLight sensitive materialsHydrophobicitySynthetic membraneNanotechnologyNano-fluidic devicesGatingIonIonic transportsBiomaterialsPolymeric membranesOptical gatingPhotosensitivityOptical gatingsSynthetic ion channelsMonolayerElectrochemistryControlled releasePhotolabile protecting groupsIonic speciesPolymer membranesHydrophobic moleculesFunctional polymersSelective permeationHydrophilicityMultifunctional devicesMonolayersIonsAqueous solutionCurrent rectificationUV-light irradiationMulti-channelPermeationCondensed Matter PhysicsNanostructuresElectronic Optical and Magnetic MaterialsData processingPhotosensitive nanostructuresFISICA APLICADAIrradiationNano channelsInner surfacesFunctional polymersCurrent voltageAdvanced Functional Materials
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Reversible oxidation of WOx and MoOx nano phases

2012

International audience; WOx and MoOx nano phases were prepared on TiO2(1 1 0) surfaces by a CVD procedure consisting of adsorption and decomposition of W(CO)(6) or Mo(CO)(6) precursors followed by annealing under UHV. Metal amount involved in each elaborated sample is in the fractional range from 0.1 to 0.35 equivalent monolayer (eqML) of W or Mo. Evolution of sample stoichiometry as a function of subsequent treatment is followed by valence band and core level photoemission as well as work function measurement. In each case, exposure of samples to molecular oxygen at room temperature induces an increase of sample work function in a range of several tenth of eV. Such a work function change i…

Materials scienceAnnealing (metallurgy)Inorganic chemistryAnalytical chemistrychemistry.chemical_elementCATALYSTS02 engineering and technologyTungsten010402 general chemistryTIO2(110) SURFACE01 natural sciencesSTOICHIOMETRYCatalysisTUNGSTEN-OXIDE[ CHIM.OTHE ] Chemical Sciences/OtherMonolayerWork functionHEXACARBONYL ADSORPTIONSOL-GELVISIBLE-LIGHT IRRADIATIONTIO2 110MOLYBDENUMGeneral Chemistry021001 nanoscience & nanotechnology0104 chemical scienceschemistryMolybdenumPhotocatalysisPHOTOCATALYSIS[CHIM.OTHE]Chemical Sciences/Other0210 nano-technologyStoichiometryTitanium
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Paper Functionalized with Nanostructured TiO2/AgBr: Photocatalytic Degradation of 2–Propanol under Solar Light Irradiation and Antibacterial Activity

2020

A facile method to produce paper&ndash

Materials scienceGeneral Chemical EngineeringPaper-TiO2NanoparticlePropanollcsh:Chemistrychemistry.chemical_compoundsymbols.namesakeantibacterial activity2-propanol photodegradationGeneral Materials SciencePaper–TiO<sub>2</sub>–AgBrPhotodegradationPaper-TiO2-AgBr; 2-propanol photodegradation; antibacterial activity; sunlight irradiationSettore CHIM/06 - Chimica OrganicaSilver bromidesunlight irradiationTitanium oxidechemistryChemical engineeringlcsh:QD1-999PhotocatalysissymbolsRaman spectroscopy-AgBrVisible spectrumNanomaterials
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LIESST Effect in Fe(II) 1,2,4-Triazole Chains

2016

One-dimensional Fe(II) chains with 1,2,4-triazole as bridging ligands present the LIESST effect; i.e. their spin state switched from low-spin to high-spin after light irradiation at low temperature. This account summarizes the findings in this area of photomagnetism where 57Fe Mossbauer spectroscopy was used as a primary detection tool of the LIESST effect.

Materials scienceSpin statesGeneral Engineering124-TriazoleLight irradiation02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistryPhotomagnetism01 natural sciencesLIESST0104 chemical scienceschemistry.chemical_compoundNuclear magnetic resonancechemistryMössbauer spectroscopyGeneral Earth and Planetary Sciences0210 nano-technologyGeneral Environmental ScienceCurrent Inorganic Chemistry
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