Search results for "Light source"

showing 10 items of 35 documents

Generation of white LED light by frequency downconversion using a perylene-based dye

2012

A high efficiency white light emitting diode (LED) was fabricated by generation of frequency down-conversion from a GaN/InGaN blue LED. In place of conventional inorganic phosphors, a perylene-based dye was used for colour conversion. The resulting hybrid structure is analysed by focusing on the visual performance of the realised LEDs employing the most relevant photometric parameters of a light source. Preparation of the organic polymer is described as well. The thermal stability of the dye was investigated and a simple structure which avoids colour degradation is proposed.

Organic polymerMaterials sciencebusiness.industryPhosphordyes light emitting diodes phosphors polymers wide band gap semiconductors GaN-InGaN blue LED colour conversionSettore ING-INF/01 - Elettronicalaw.inventionchemistry.chemical_compoundOpticsLight sourcechemistrylawOptoelectronicsDegradation (geology)Thermal stabilityElectrical and Electronic EngineeringbusinessPeryleneDiodeLight-emitting diode
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Komparativno istraživanje oblikovanja četiriju rotirajućih sustava

2015

Svrha: U ovom istraživanju analizirali smo rezno područje, vrijeme instrumentacije, održavanje anatomije korijenskog kanala i neinstrumentirana područja dobivena korištenjem instrumenata F360®, Mtwo®, RaCe® i Hyflex® u ISO veličini 35. Materijali i metode: Odabrano je 120 zuba s jednim ravnim kanalom i podijeljeni su u četiri grupe. Radna duljina određena je radiološki. Zubi su rezani dijamantnim diskom, a presjeci su promatrani stereoskopskim mikroskopom Nikon SMZ-2T pod svjetiljkom Intralux 4000-1. Grupe su oblikovane predoperativnom analizom AutoCAD. Zubi su rekonstruirani s pomoću K-proširivača #10 i epoksi ljepila. Svaka grupa instrumentirana je jednim od četiriju sustava. Vrijeme inst…

OrthodonticsInstrumentationRoot canalTooth PreparationA diamondDental High-Speed Equipmentlcsh:RK1-715Light sourcemedicine.anatomical_structurelcsh:DentistryStereo microscopemedicineStatistical analysispreparacija korijenskog kanala brzo rotirajuća stomatološka oprema priprema zuba; poprečni presjecicross-sectionsRoot canal anatomyRoot Canal Preparation; Dental High-Speed Equipment; Tooth Preparation; cross-sectionsGeneral DentistryRoot Canal PreparationResearch ArticleMathematicsActa Stomatologica Croatica
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Review of RGB photoelasticity

2015

Abstract Automatic methods of photoelasticity have had a significant progress with the development of automatic acquisition and image processing methods. This article concerns RGB photoelasticity, which allows the determination of the photoelastic retardation using, usually, a single acquisition of the isochromatic fringes in white light by a colour camera. In particular, the article presents an overview of the main characteristics of RGB photoelasticity that is influence of the quarter-wave plate error, number of acquisitions, type of light source, determination of low and high fringe orders, methods for searching the retardation, scanning procedures, calibration on a material different fr…

PhotoelasticityComputer sciencebusiness.industryMechanical EngineeringCombined useImage acquisition and elaborationImage processingRGB photoelasticity; Image acquisition and elaboration; Experimental mechanicsAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsRGB photoelasticitySettore ING-IND/14 - Progettazione Meccanica E Costruzione Di MacchineLight sourceExperimental mechanicsComputer graphics (images)Lookup tableWhite lightCalibrationRGB color modelComputer visionArtificial intelligenceElectrical and Electronic EngineeringbusinessSettore ING-IND/15 - Disegno E Metodi Dell'Ingegneria Industriale
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Convenient Photochemical Synthesis of Silver-Polyaminocyclodextrin Nanocomposites: The Role of the Light Source from a Mechanistic Viewpoint

2018

An investigation on the light-driven reduction of the [Ag(NH3)2]+complex in the presence of polyaminocyclodextrins was carried out, in order to clarify the mechanism of the process. The role of the organic auxiliary as both the sacrificial reductant and the capping agent was positively assessed. Moreover, particular attention was paid to the role of the irradiation source. Experimental results indicate that a complex mechanism is involved in the formation of the nanocomposite, with a primary photoinduced single-electron-transfer process promoted by irradiation with green light, followed by a secondary chemical reduction process activated by NIR. Representative composites were characterized …

PhotoreductionNanocompositeSilverChemistryChemistry (all)02 engineering and technologyGeneral ChemistrySettore CHIM/06 - Chimica Organica010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciences0104 chemical sciencesLight sourceNanoparticleCyclodextrinAntimicrobial0210 nano-technologySettore CHIM/02 - Chimica Fisica
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Das Vorzeichen der Hyperfeinstruktur-Aufspaltung des 3d 5 4s 2 6 S 5/2-Grundzustandes des Mn55

1962

Using a double Fabry-Perot interferometer and an atomic-beam light source, the sign of the hyperfine-structure splitting of the 3d 5 4s 2 6 S 5/2 ground state of Mn55 has been determined to be negative. The absolute value of the splitting previously has been measured byWoodgate andMartin.

PhysicsNuclear and High Energy PhysicsLight sourceAbsolute valueAtomic physicsGround stateHyperfine structureSign (mathematics)Zeitschrift für Physik
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New results from testing of coplanar-grid CdZnTe detectors

2005

New results from studies of coplanar-grid CdZnTe (CZT) detectors are presented. The coplanar-grid detectors were investigated by using a highly collimated X-ray beam available at Brookhaven's National Synchrotron Light Source and by applying a pulse-shape analysis. The coplanar-grid detector operates as a single-carrier device. Despite the fact that its operational principle is well known and has been investigated by many groups in the past, we found some new details that may explain the performance limits of these types of devices. The experimental results have been confirmed by extensive computer modeling.

PhysicsPhysics::Instrumentation and Detectorsbusiness.industryDetectorSynchrotron radiationParticle acceleratorGridCollimated lightParticle detectorlaw.inventionNational Synchrotron Light SourceOpticslawbusinessBeam (structure)Hard X-Ray and Gamma-Ray Detector Physics VII
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Using Partial Coherence and Digital Holography for 3D Imaging and Profile Extraction

2008

Two approaches for 3D imaging are presented. At first we use partial coherence of the light source and in the second we compute the unwrapped phase by illuminating the object from several slightly different angles.

Physicsbusiness.industryPhase (waves)HolographyImage processinglaw.inventionLight sourceOpticsInterference (communication)lawSpatial frequencybusinessDigital holographyPartial coherenceDigital Holography and Three-Dimensional Imaging
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Numerical procedures and their practical application in PV modules analyses. Part I: air mass

2019

Abstract The subject of the article is aspects of PV modules and cells measurement, with the use of natural sunlight. A light source is an important element during calibration and measurements of solar cells and modules. All designers of artificial light sources try to recreate natural light using so called measurement tables. The correctly performed measurement, i.e. meeting all the appropriate atmospheric conditions, guarantees obtaining the result with the use of a reference spectrum. The article has two main aims. The first aim of the article is to answer the question asked earlier - if the sunlight spectrum registered in appropriate conditions is so good that it serves as the reference…

RadiationArtificial lightComputer scienceSpectral responseControl engineering02 engineering and technologyAir mass (solar energy)021001 nanoscience & nanotechnologySunlight radiation intensity01 natural sciences010309 opticsSunlight radiation spectrumLight source0103 physical sciencesCalibrationSolar powerGeneral Materials ScienceElectrical and Electronic Engineering0210 nano-technologyGeographic coordinate systemSolar power industryOpto-Electronics Review
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Simple and convenient remote photoplethysmography system for monitoring regional anesthesia effectiveness

2017

Simple and inexpensive remote photoplethysmography system for monitoring the effectiveness of regional anesthesia was developed and tested. The system involves surgical lamp as light source, compact video camera and computer with custom developed software. Data from eight patients were processed and the effectiveness of regional anesthesia was calculated. The results showed that the standard surgical lamp can be used as a light source together with camera for remote monitoring of regional anesthesia effectiveness.

SIMPLE (military communications protocol)Computer sciencebusiness.industryComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONVideo cameraSkin perfusion01 natural scienceslaw.invention010309 optics03 medical and health sciences0302 clinical medicineSoftwareLight sourceRegional anesthesialawPhotoplethysmogramAnesthesia0103 physical sciencesComputer visionArtificial intelligencebusiness030217 neurology & neurosurgery
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Photoelectrocatalytic reactors and light sources

2023

Photoelectrocatalysis (PEC) couples electrochemical methods with photocatalysis (PC) to enhance the separation of the photoproduced electron and hole pairs at semiconductor active surface, thus increasing the photocatalytic efficiency. PEC technology is considered one of the most promising method for processes as water treatment, fuel generation, and PEC sensing. This chapter try to link fundamental research and practical applications in photoelectrochemical engineering including reactors design strategies in different scales.

Settore ING-IND/24 - Principi Di Ingegneria ChimicaLight sources PEC reactors Reactor designSettore CHIM/07 - Fondamenti Chimici Delle Tecnologie
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