Search results for "Visible spectrum"

showing 5 items of 155 documents

Efficient Conversion of Light to Chemical Energy : Directional, Chiral Photoswitches with Very High Quantum Yields

2020

Abstract Photochromic systems have been used to achieve a number of engineering functions such as light energy conversion, molecular motors, pumps, actuators, and sensors. Key to practical applications is a high efficiency in the conversion of light to chemical energy, a rigid structure for the transmission of force to the environment, and directed motion during isomerization. We present a novel type of photochromic system (diindane diazocines) that converts visible light with an efficiency of 18 % to chemical energy. Quantum yields are exceptionally high with >70 % for the cis–trans isomerization and 90 % for the back‐reaction and thus higher than the biochemical system rhodopsin (64 %). T…

energy conversionMaterials science116 Chemical sciences010402 general chemistry01 natural sciencesCatalysisPhotochromismMolecular motorEnergy transformationQuantumquantum yieldsphotochemistry010405 organic chemistrybusiness.industryCommunicationdiazocineDiastereomerGeneral ChemistryphotochromismCommunications0104 chemical sciencesChemical energyOptoelectronicsvalokemiabusinessIsomerizationVisible spectrum
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Identifying Iron-Bearing Nanoparticle Precursor for Thermal Transformation into the Highly Active Hematite Photo-Fenton Catalyst

2020

Funding: This reseach was funded by the European Regional Development Fund within the Activity 1.1.1.2 “Post-doctoral Research Aid” of the Specific Aid Objective 1.1.1 “To increase the research and innovative capacity of scientific institutions of Latvia and the ability to attract external financing, investing in human resources and infrastructure” of the Operational Programme “Growth and Employment” (No. 1.1.1.2/VIAA/1/16/157).

inorganic chemicalsPhoto-FentonGoethiteMaterials scienceHematiteNanoparticlelcsh:Chemical technology010402 general chemistry01 natural sciences7. Clean energyCatalysishematiteCatalysislcsh:Chemistryphoto-Fenton:NATURAL SCIENCES:Physics [Research Subject Categories]Goethitegoethitelcsh:TP1-1185Reactivity (chemistry)Physical and Theoretical ChemistryAqueous solutionWater purification010405 organic chemistryHematite0104 chemical sciencesAmorphous solidlcsh:QD1-999Chemical engineering13. Climate actionvisual_artvisual_art.visual_art_mediumwater purificationVisible spectrumCatalysts
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Octave Spanning Supercontinuum in Titanium Dioxide Waveguides

2018

International audience; We report on the experimental generation of an octave-spanning supercontinuum in a 2.2 cm-long titanium dioxide optical waveguide with two zero dispersion wavelengths. The resulting on-chip supercontinuum reaches the visible wavelength range as well as the mid-infrared region by using a femtosecond fiber laser pump at 1.64 µm.

integrated optics; supercontinuum generation; titanium dioxidePhysics::Optics02 engineering and technologyFemtosecond fiber laser01 natural sciences7. Clean energylcsh:Technologylaw.inventionlcsh:Chemistrychemistry.chemical_compoundlawDispersion (optics)General Materials ScienceInstrumentationlcsh:QH301-705.5ComputingMilieux_MISCELLANEOUSFluid Flow and Transfer Processes[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics][ PHYS.PHYS.PHYS-OPTICS ] Physics [physics]/Physics [physics]/Optics [physics.optics]General Engineering021001 nanoscience & nanotechnologylcsh:QC1-999Computer Science ApplicationsWavelengthintegrated opticsFemtosecondOptoelectronicsIntegrated optics0210 nano-technologyVisible spectrum[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics]Materials scienceAstrophysics::Cosmology and Extragalactic AstrophysicsOctave (electronics)010309 optics0103 physical sciencesSelf-phase modulationsupercontinuum generationbusiness.industrytitanium dioxidelcsh:TProcess Chemistry and TechnologyLaserSupercontinuumchemistrylcsh:Biology (General)lcsh:QD1-999lcsh:TA1-2040Titanium dioxidebusinesslcsh:Engineering (General). Civil engineering (General)Refractive indexlcsh:PhysicsApplied Sciences
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The relationship between visible light emission and species fraction of the hydrogen ion beams extracted from 2.45 GHz microwave discharge.

2015

The relationship between Balmer-α and Fulcher-band emissions with extracted H + , H + 2 , and H + 3 ions is demonstrated for a 2.45 GHz microwave discharge. Ion mass spectra and optical measurements of Balmer-α and Fulcher-band emissions have been obtained with a Wien Filter having an optical viewport on the plasma chamber axis. The beam of approximately 1 mA is analyzed for different plasma conditions simultaneously with the measurement of light emissions both with temporal resolution. The use of visible light emissions as a valuable diagnostic tool for monitoring the species fraction of the extracted beams is proposed. peerReviewed

plasma sourcesMaterials scienceWien filterta114Astrophysics::High Energy Astrophysical Phenomenaelektrodition beamsAstrophysics::Cosmology and Extragalactic AstrophysicsPlasmaelectrodesIonion sourcesPhysics::Plasma PhysicsTemporal resolutionMass spectrumPlasma diagnosticsAtomic physicsInstrumentationvisible lightAstrophysics::Galaxy AstrophysicsMicrowaveVisible spectrumThe Review of scientific instruments
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Photocatalytic nano-composite architectural lime mortar for degradation of urban pollutants under solar and visible (interior) light

2017

Abstract Recent advances in nano-technology and nano-additives can give enhanced properties to natural hydraulic lime (NHL), creating a multifunctional material. We have prepared a novel nanocomposite, made of a commercial mortar with 1 wt% and 5 wt% added titania nanoparticles (NPs). These TiO 2 NPs are themselves doped with 1 mol% silver, to give the material enhanced photocatalytic and antimicrobial properties. The Ag-doped TiO 2 NPs were made from a simple, costs effective, aqueous green nanosynthesis process, and the end material only contains 0.01–0.05% Ag. As this mortar is intended to both combat atmospheric pollution, and create more durable/lower maintenance building facades (plas…

xTitaniaMaterials scienceSettore ING-IND/22 - Scienza e Tecnologia dei MaterialiSettore ICAR/10 - Architettura Tecnica02 engineering and technology010501 environmental sciencesengineering.material01 natural sciencesNOCoatingGeneral Materials SciencePhotocatalysisLime mortarComposite materialCuring (chemistry)0105 earth and related environmental sciencesCivil and Structural EngineeringSettore CHIM/03 - Chimica Generale e InorganicaNanocompositeNanocompositeSettore CHIM/07 - Fondamenti Chimici delle TecnologieHydraulic limeBuilding and Construction021001 nanoscience & nanotechnologyMortarengineeringPhotocatalysisMortar Natural hydraulic lime Photocatalysis NOx Titania NanocompositeNatural hydraulic limeMortar0210 nano-technologyMortar; Nanocomposite; Natural hydraulic lime; NO; x; Photocatalysis; TitaniaVisible spectrum
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