Search results for "Volt"

showing 10 items of 2187 documents

E-sail test payload of the ESTCube-1 nanosatellite

2014

The scientific mission of ESTCube-1, launched in May 2013, is to measure the electric solar wind sail (E-sail) force in orbit. The experiment is planned to push forward the development of the E-sail, a propulsion method recently invented at the Finnish Meteorological Institute. The E-sail is based on extracting momentum from the solar wind plasma flow by using long thin electrically charged tethers. ESTCube-1 is equipped with one such tether, together with hardware capable of deploying and charging it. At the orbital altitude of ESTCube-1 (660–680 km) there is no solar wind present. Instead, ESTCube-1 shall observe the interaction between the charged tether and the ionospheric plasma. The E…

Physicsta114Payloadbusiness.industryGeneral EngineeringPropulsionlaw.inventionSlip ringSolar windlawElectric sailAerospace engineeringIonosphereSpace researchbusinessVoltageProceedings of the Estonian Academy of Sciences
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An absence of neutrinos associated with cosmic-ray acceleration in gamma-ray bursts

2012

Gamma-Ray Bursts (GRBs) have been proposed as a leading candidate for acceleration of ultra high-energy cosmic rays, which would be accompanied by emission of TeV neutrinos produced in proton-photon interactions during acceleration in the GRB fireball. Two analyses using data from two years of the IceCube detector produced no evidence for this neutrino emission, placing strong constraints on models of neutrino and cosmic-ray production in these sources.

Physics::Instrumentation and DetectorsAstronomyAstrophysics::High Energy Astrophysical PhenomenaElectronvoltFOS: Physical sciencesFluxhigh-energy neutrinosCosmic rayddc:500.2AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysics7. Clean energy01 natural sciencesddc:070IcecubeAccelerationPioncosmic rays0103 physical sciencesTelescope010303 astronomy & astrophysicsVery EnergeticHigh Energy Astrophysical Phenomena (astro-ph.HE)PhysicsFluxMultidisciplinary010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologySearchAstrophysics::Instrumentation and Methods for Astrophysics13. Climate actionGamma Ray BurstsHigh Energy Physics::ExperimentNeutrinoGamma-ray burstAstrophysics - High Energy Astrophysical PhenomenaNATURE
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π conjugation across the tetrathiafulvalene core: Synthesis of extended tetrathiafulvalene derivatives and theoretical analysis of their unusual elec…

2000

A series of extended tetrathiafulvalene (TTF) derivatives bearing one or two 1,4-dithiafulven-6-yl substitutents has been prepared. The new compounds present remarkable electrochemical singularities compared with other TTF derivatives, which are strongly affected by the nature of the substitution on the lateral heterocycle(s). This unusual electrochemical behaviour follows a square-scheme sequence and is attributed to structural changes upon oxidation of the pi-donating molecules. Digital simulations of the electrochemical data have been used to reach the values of the kinetic and thermodynamic constants involved in the square scheme. Theoretical calculations establish an important contribu…

Pi systemOrganic ChemistryInorganic chemistryNonlinear opticsGeneral ChemistryConjugated systemElectrochemistryCatalysischemistry.chemical_compoundCrystallographychemistryAb initio quantum chemistry methodsMoleculeCyclic voltammetryTetrathiafulvalene
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Le absidi delle chiese Madri di Assoro e Pietraperzia (XV-XVI secolo)

2015

This contribution focuses on two case studies dating from the 15th and 16th centuries: the apse of the mother church of Assoro and the mother church of Pietrap- erzia, both in the province of Enna, for which it is pos- sible to identify common constructive characteristics and a close relationship including in terms of the clients involved. The study examines historical aspects and those of a geometric and construction nature, taking also into ac- count the lasting influence of the apse. The investigation, hampered by the limited archival sources, both literary and iconographical, is based on the study of the few documentary records found, as well on the direct survey and examination of the …

PietraperziaPietraperzia; Assoro; Sicilia nel XV-XVI secolo; absidi ottagonali; sistemi voltati.Sicilia nel XV-XVI secoloAssoroabsidi ottagonaliPietraperzia Assoro Sicilia nel XV-XVI secolo absidi ottagonali sistemi voltati.Settore ICAR/18 - Storia Dell'Architetturasistemi voltati
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Piezoelectric model of rainfall energy harvester

2014

In this paper a model to predict the harvest of the energy contained in rainfall by means of piezoelectric transducers is presented. Different studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, in order to limit optimistic forecasts, compares the behavior of the transducers subjected to real and artificial rainfall, a condition that has shown promising behavior in laboratory.

Piezoelectric coefficientPiezoelectric accelerometerPiezoelectric sensorAcousticsenergy harvester piezoelectric effectSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciPiezoelectricitySettore ING-INF/01 - ElettronicaPower (physics)Settore ING-IND/31 - ElettrotecnicaTransducerPMUTEnvironmental scienceSettore ING-INF/07 - Misure Elettriche E ElettronicheVoltage
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Light trapping by plasmonic nanoparticles

2020

Abstract Metallic nanoparticles sustaining localized surface plasmon resonances are of great interest for enhancing light trapping in thin film photovoltaics. In this chapter, we explore the correlation between the structural and optical properties of self-assembled silver nanostructures fabricated by a solid-state dewetting process on various substrates relevant for silicon photovoltaics and later integrated into plasmonic back reflectors. Our study allows us to optimize the performance of nanostructures by identifying the fabrication conditions in which desirable circular and uniformly spaced nanoparticles are obtained. Second, we introduce a novel optoelectronic spectroscopic method that…

Plasmonic nanoparticlesMaterials scienceSiliconbusiness.industryPhysics::Opticschemistry.chemical_elementSettore ING-INF/01 - ElettronicachemistryPhotovoltaicsLight trapping Localized surface plasmon resonance Photocurrent enhancement Plasmon-enhanced Self-assembly Silver nanoparticles Thin film silicon solar cellsOptoelectronicsQuantum efficiencyDewettingThin filmbusinessPlasmonLocalized surface plasmon
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Plasmonic nanostructures for light trapping in photovoltaic

Metallic nanoparticles (NPs), sustaining localized surface plasmon resonances, are currently of great interest for enhancing light trapping in thin film solar cells. To be directly applicable in the photovoltaic industry, the NPs fabrication needs to be simple, reliable, low-cost and scalable. As such, self-assembly processes are most commonly used, and Ag is the preferred material, due to its high radiative efficiency and low imaginary permittivity⁠. After exploring the correlation between structural and optical properties of Ag NPs fabricated by solid- state dewetting process on various substrates, we identified the fabrication conditions in which desirable NPs are obtained, but we also e…

Plasmonic-enhanced light trapping Localized surface plasmon resonance Self-assembly nanoparticles PhotovoltaicsSettore ING-INF/01 - Elettronica
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Calculation of voltammetric peaks by the transformed Heyrovsky-Ilkovi? equation

1990

Calculating real polarographic or voltammetric peaks is rather difficult. A new possibility to compute such peaks is the use of the transformed Heyrovsky-Ilkovic equation. The calculation allows to simulate polarograms or voltammograms by computer. Furthermore, it is possible to smooth voltammetric peaks without loss of peak height or separation of overlapping peaks.

PolarographyChemistryComputer aidAnalytical chemistryBiochemistryVoltammetryAnalytical ChemistryFresenius' Journal of Analytical Chemistry
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Electrochemical study of intramolecular charge transfer complexes derived from 1,4-naphthoquinone Part 1. Electroreduction

1995

Abstract Electrochemical investigations (polarography, cyclic voltammetry, rotating ring-disk electrode voltammetry) of intramolecular charge transfer complexes (AC) derived from 1,4-naphthoquinone were performed in acetonitrile. It is concluded that in the first one-electron stage of its electrochemical reduction the AC is in a complexed form. At the same time the amino moiety, which shows a marked inductive (−I) effect, acts as an electron donor in the donor-acceptor (D-A) interaction. Facilitation of the reduction of the quinone part by the aryl amine residue is compensated by the D-A interaction, which makes the electroreduction more difficult. By using ultramicroelectrodes it was shown…

PolarographyChemistryGeneral Chemical EngineeringInorganic chemistryElectron donorUltramicroelectrodeAnalytical Chemistrychemistry.chemical_compoundIntramolecular forceElectrochemistryMoietyCyclic voltammetryAcetonitrileVoltammetryJournal of Electroanalytical Chemistry
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Electrochemical reactions with adsorption of the reactants and electrosorption. Simple analytical solutions for a Henry isotherm

1998

Abstract A theoretical treatment of an electrochemical reaction O + ne− R with adsorption of the reactants is presented when the adsorption, at equilibrium, obeys a Henry isotherm. A simple analytical solution, valid for any degree of adsorption of O and or R, is established for a polarographic wave. In LSV, for slow sweep rates and weak adsorption, both the cathodic and anodic peaks have a ‘diffusional’ character; for high sweep rates and strong adsorption, they are both of a ‘surface’ nature. In the intermediate case, one peak has a ‘diffusional’ character (deposition process), while the other is of a ‘surface’ nature (redissolution process). Expressions of the peak potentials are given i…

PolarographyReaction mechanismAdsorptionReaction rate constantChemistryGeneral Chemical EngineeringLinear sweep voltammetryElectrochemistryPhysical chemistrySorptionElectrochemistryAnalytical ChemistryAnodeJournal of Electroanalytical Chemistry
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