Search results for "charges"

showing 10 items of 48 documents

The effect of Transient over Voltages on the Partial Discharges activity in HVDC joints

2021

Rapid growth of HVDC cable line installations is expected in the coming years. Several research groups have investigated dielectric phenomena that occur in the insulation of HVDC cables and accessories that accelerate aging and reduce the reliability of this technology over time. Unlike in HVAC cables, under HVDC stress, the distribution of the electric field inside the insulation layer depends not only on the applied voltage but also on the temperature distribution and on other factors related to manufacturing such as the presence of impurities. Reaching local and transient electric field peaks can enhance the onset of Partial Discharges (PDs) which can lead to premature aging of the insul…

Premature agingMaterials scienceHVDCPartial Dischargesfood and beveragesSpace ChargeDielectricMechanicsSpace chargeStress (mechanics)Transient Over VoltagesOvervoltageElectric fieldDielectric phenomenaTransient (oscillation)Voltage
researchProduct

Toward more realistic viscosity measurements of tyre rubber–bitumen blends

2014

AbstractThe measurement of rheological properties of the tyre rubber bitumen blends is often challenging due to presence of suspended tyre rubber’s crumbs. Furthermore, the phase separation during the course of measurements makes the viscosity of these non-homogeneous blends difficult to ascertain. In this study, a new dual helical impeller was designed and manufactured to be used with a rotational viscometer in order to have a real-time control of the viscosity while performing a laboratory mixing of the blends. Layer based manufacturing techniques showed to be a convenient method to produce complex shaped impeller prototypes before manufacturing the more expensive stainless steel assembly…

Recycled tyre rubberEngineeringbituminous materials Calibration Electric discharges Impellers Manufacture Rapid prototyping Rate constants Real time control Rubber Stainless steel Tires Viscometers Viscosity Viscosity measurementViscometryMixing (process engineering)ViscosityImpellerMaterials Science(all)Natural rubberRheologyElectrical discharge machiningSettore ICAR/04 - Strade Ferrovie Ed AeroportiGeneral Materials ScienceComposite materialCivil and Structural EngineeringComplex fluidRapid prototypingbusiness.industryViscometerBuilding and ConstructionDual helical impellerShear rateRubberised bitumenvisual_artvisual_art.visual_art_mediumSettore ICAR/08 - Scienza Delle CostruzionibusinessConstruction and Building Materials
researchProduct

Loyers et charges d'un bail commercial. Indemnité versée au bailleur pour permettre la cession du bail

2022

(Com. 18 mai 2022, no 20-22.623, F-D, Mme G., ès qual. c/ M. V. ; Com. 23 mars 2022, no 20-22.284, M. K. c/ Mme I. et a., Gaz. Pal. 19 avr. 2022, p. 57, obs. J.-L.Vallens ; RJDA 2022, no 350)

Sauvegarde Des Entreprises[SHS.DROIT] Humanities and Social Sciences/LawCréance de loyers et chargesCréance privilégiéeCréance postérieureIndemnité transactionnelle
researchProduct

Characteristics of partial discharges in an experimental setup reproducing HVDC cable insulation operating conditions

2021

The occurrence of Partial Discharge (PD) inside a cavity subjected to HVDC voltage can be considered as one of the most likely sources of insulation ageing and failure. In practical applications, the recognition of PD under HVDC is more difficult than under AC stress because of the lower repetition rates and the impossibility to obtain a PD pattern synchronized with the waveform of the applied voltage. In this paper, the relationship between conduction phenomena in dielectrics and the occurrence of PD is investigated by means of a novel experimental setup. A couple of dielectric cells connected in series is subjected to various HVDC stress levels. The applied voltage is divided between the …

Settore ING-IND/31 - ElettrotecnicaHVDC partial discharges space charge dielectric phenomena2021 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)
researchProduct

A digital device for the diagnosis of insulation systems

2004

A complete innovative measurement system (D2SI - device for the diagnosis of insulation systems) for both acquisition, analysis and processing of partial discharge signals generated in insulation systems under voltage stress (IEC standard), was designed and realized; several measurements on practical insulation systems demonstrated the full and correct equipment operation.

Stress (mechanics)EngineeringDigital devicebusiness.industrySystem of measurementPartial dischargeElectrical engineeringDielectrics and electrical insulation Partial discharge measurement Stress measurement Signal analysis Partial discharges Signal processing Signal generators Voltage IEC standards Signal designIec standardsbusinessVoltageThe 17th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2004. LEOS 2004.
researchProduct

International Legal Approaches to Waste Water Discharges. Opening speech

2002

En este discurso inaugural, realizo una introducción a la frustrante situación jurídica en la que se encuentran las descargas de aguas residuales a nivel internacional. Las descargas de aguas residuales son la mayor fuente de contaminación marina y, en consecuencia, ellas representan el mayor riesgo actual para la protección del medio ambiente marino. In this opening speech, I make an introduction to the disappointing legal situation of waste water discharges at international level. Waste water discharges is the main source of marine pollution and, therefore, they represent the major current risk to the protection of the marine environment.

Waste water dischargesProtección del medio ambiente marinoContaminación marina:CIENCIAS JURÍDICAS Y DERECHO [UNESCO]Marine pollutionUNESCO::CIENCIAS JURÍDICAS Y DERECHODescargas de aguas residualesProtection of the marine environment
researchProduct

Interictal Heart Rate Variability Analysis Reveals Lateralization of Cardiac Autonomic Control in Temporal Lobe Epilepsy.

2020

International audience; Purpose: The temporal lobe, a critical hub for cognition, also plays a central role in the regulation of autonomic cardiovascular functions. Lesions in this area are usually associated with abnormalities in the regulation of heart rate (HR) and blood pressure (BP). The analysis of the heart rate variability (HRV) is useful to evaluate the cardiac parasympathetic nervous system activity. This study aims at comparing HRV changes occurring in two groups of patients suffering from Temporal Lobe Epilepsy (TLE). To that aim, we evaluated patients differentiated by the right or left location of the epileptic foci. Materials and Methods: Fifty-two adult patients with a diagn…

cardiovascular riskmedicine.medical_specialty030204 cardiovascular system & hematologySudden deathinterictal epileptic dischargebehavioral disciplines and activitiesinterictal epileptic dischargeslcsh:RC346-429Temporal lobe03 medical and health sciencesEpilepsy0302 clinical medicine[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular systemInternal medicineHeart ratemedicineHeart rate variabilityIctallcsh:Neurology. Diseases of the nervous systemOriginal Researchbusiness.industrySeizure typesautonomic nervous systemheart rate variabilitytemporal lobe epilepsymedicine.diseasenervous system diseasesAutonomic nervous systemNeurologyCardiologySettore MED/26 - Neurologia[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]Neurology (clinical)business030217 neurology & neurosurgeryFrontiers in neurology
researchProduct

Electrotechnologies, microwaves, and ultrasounds combined with binary mixtures of ethanol and water to extract steviol glycosides and antioxidant com…

2017

The aim of this work was to investigate the potential use of non-conventional technologies (microwaves, ultrasounds, pulsed electric fields, and high voltage electrical discharges) to enhance the extraction of high-added value compounds (mainly stevioside and rebaudioside A), and antioxidants (total phenolic compounds, flavonoids, chlorophylls, and carotenoids), from Stevia rebaudiana leaves. After treatment at equivalent energy, a supplementary diffusion was performed until 1 h. Results demonstrated that when water (100%) was used as solvent, the maximum recovery of stevioside (50.8 ± 0.1 mg/g) was obtained after ultrasound-assisted extraction, while microwave allowed the highest yields of…

chemistry.chemical_classificationDownstream processingChromatographyGeneral Chemical Engineering010401 analytical chemistryExtraction (chemistry)GlycosideSteviol04 agricultural and veterinary sciencesGeneral Chemistry040401 food science01 natural scienceshigh voltage electrical discharges ; microwaves ; pulsed electric fields ; stevia rebaudiana Bertoni ; ultrasounds0104 chemical sciencesSolventStevia rebaudianachemistry.chemical_compound0404 agricultural biotechnologychemistryOrganic chemistrySteviosideRebaudioside AFood Science
researchProduct

Synthesis, crystal structure, DFT calculations, Hirshfeld surface, vibrational and optical properties of a novel hybrid non-centrosymmetric material …

2019

This present work undertakes the study of a novel organic–inorganic hybrid material, which has been obtained successfully by an acid-base reaction at room temperature and structurally studied by the single crystal X-ray diffraction method. (C10H15N2)2H2P2O7 crystallizes in the triclinic system with the non-centrosymmetric space group P1 with the following lattice parameters: a = 5.9159(2) Å, b = 13.8451(6) Å, c = 14.5973(5) Å, ? = 74.507(2)°, ? = 89.980(2)°, ? = 89.231(2)° with V = 1152.06(8) Å3 and Z = 2. The X-ray structural analysis supported by a detailed Hirshfeld 2D fingerprint plots has been performed to elucidate the different inter-contacts in the crystal structure mainly associate…

crystal structure010405 organic chemistryChemistryOrganic ChemistryMulliken chargesCrystal structureTriclinic crystal systemMEP010402 general chemistry01 natural sciencesDFT0104 chemical sciencesAnalytical Chemistrynon-centrosymmetric hybrid materialInorganic ChemistryCrystallographyMolecular vibrationNon–centrosymmetric hybrid materialDensity functional theoryHOMO-LUMOGround stateMulliken population analysisSingle crystalSpectroscopyBasis set
researchProduct

A study of VUV emission and the extracted electron-ion ratio in hydrogen and deuterium plasmas of a filament-driven H−/D− ion source

2019

Vacuum ultraviolet (VUV) emission diagnostics for studying differences of electron impact processes in hydrogen and deuterium plasmas are presented. The method is applied to study a filament driven multicusp arc discharge negative ion source by comparing the VUV-emission intensities of different emission bands and extracted currents of H−/D− ions and electrons. It was found that the ratio of coextracted electrons to extracted ions is four times higher for deuterium than for hydrogen. No significant differences of the VUV-spectra or volumetric rates of ionization, excitation, production of high vibrational states, and dissociation were found between the plasmas of the two isotopes. The volum…

diffusion rateisotoopitplasma diagnosticselectron impact ionizationplasmafysiikkavacuum ultraviolet radiationelectron impact emission spectroscopyion sourcesPhysics::Plasma Physicselectric dischargesPhysics::Atomic and Molecular Clustersisotopesvibrational statesplasma spectroscopy
researchProduct