Search results for "conduct"

showing 10 items of 4412 documents

Low toxicity metal halide semiconductors for optoelectronics and thermoelectrics

2023

Amb la finalitat de lluitar contra el canvi climàtic i donar suport a les energies renovables i no contaminants, l'objectiu principal d'aquesta tesi és la cerca i l'estudi de nous materials amb potencial aplicació en tres grans àrees d'investigació: la fotovoltaica, la termoelèctrica i els díodes emissors de llum (LED). Atés que molts dels materials emprats en aquestes àrees contenen components tòxics i nocius per al medi ambient, els materials desenvolupats en aquesta tesi a més presenten una baixa toxicitat i es poden preparar mitjançant mètodes de síntesis i deposició més sostenibles i ecològics. Concretament, es van utilitzar dos mètodes de síntesis: la mecanosíntesi en sec per molta de…

semiconductoresmaterialesLEDsfotovoltaicaUNESCO::QUÍMICAtermoeléctricaoptoelectrónica
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Low cost, efficient hybrid solar cells

2017

Actualmente, existen diversas estrategias para producir energía limpia mediante fuentes renovables, pero es la explotación directa de la energía del Sol la que se presenta como una solución ideal, siendo la mayor fuente de energía verde en la Tierra. La potencia de la energía solar que llega a la Tierra cada año es del orden de 86000 TW (Terawatt, 1012 Watt). Esto representa 4800 veces la demanda energética anual del mundo, estimada en 18 TW. Además, todos los depósitos de energía fósil reconocidos (petróleo, carbón y gas) contienen todos juntos tan sólo una cantidad de energía equivalente a la recibida del Sol durante 56 días. Esta situación muestra claramente la necesidad de aprovechar es…

semiconductoresmoleculas organicas:FÍSICA [UNESCO]UNESCO::FÍSICAenergia solar
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Demo 49. Termómetro de resistencia

2013

Objetivo: Entender el funcionamiento de los termómetros de resistencia. Observar cómo la resistencia eléctrica varía con la temperatura de dos formas diferentes.

semiconductorestemperaturatermodinámicaresistenciacoeficiente de temperatura
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Ionic-electronic interaction in optoelectronic and sensing devices

2016

En este trabajo se estudian las interacciones entre cargas electrónicas e iónicas y sus aplicaciones en sensores y dispositivos optoelectrónicos. El mecanismo de funcionamiento de los dispositivos optoelectrónicos actualmente más comunes, como los transistores de efecto de campo de capa fina (TFTs), los diodos emisores de luz (LEDs) y las células solares se basa solamente en procesos electrónicos, lo que significa que los efectos de cargas iónicas están ausentes, son irrelevantes o incluso perjudiciales para el propósito de dichos dispositivos. Sin embargo, muchas aplicaciones se benefician de la presencia de iones en la estructura de un dispositivo. Un ejemplo típico en el campo de investi…

semiconductorestransistorescélulas solareselectrolitossensoresperovskitadispositivos emisores de luz
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Charge Transport Mechanisms in Heavy-Ion Driven Leakage Current in Silicon Carbide Schottky Power Diodes

2016

Under heavy-ion exposure at sufficiently high reverse bias voltages silicon carbide (SiC) Schottky diodes are observed to exhibit gradual increases in leakage current with increasing ion fluence. Heavy-ion exposure alters the overall reverse current-voltage characteristics of these diodes, leaving the forward characteristics practically unchanged. This paper discusses the charge transport mechanisms in the heavy-ion damaged SiC Schottky diodes. A macro model, describing the reverse current-voltage characteristics in the degraded SiC Schottky diodes is proposed. peerReviewed

silicon carbide (SiC)Materials scienceAnnealing (metallurgy)Schottky barrierSchottky diodesMetal–semiconductor junction01 natural sciencesTemperature measurementpower semiconductor deviceschemistry.chemical_compoundstomatognathic system0103 physical sciencesSilicon carbidecurrent-voltage characteristicsElectrical and Electronic EngineeringSafety Risk Reliability and QualityDiode010302 applied physicsta114ta213010308 nuclear & particles physicsbusiness.industrySchottky diodemodelingElectronic Optical and Magnetic MaterialschemistryOptoelectronicsbusinession radiation effectsVoltageIEEE Transactions on Device and Materials Reliability
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Mentalizing eye contact with a face on a video : Gaze direction does not influence autonomic arousal

2018

Recent research has revealed enhanced autonomic and subjective responses to eye contact only when perceiving another live person. However, these enhanced responses to eye contact are abolished if the viewer believes that the other person is not able to look back at the viewer. We purported to investigate whether this “genuine” eye contact effect can be reproduced with pre‐recorded videos of stimulus persons. Autonomic responses, gaze behavior, and subjective self‐assessments were measured while participants viewed pre‐recorded video persons with direct or averted gaze, imagined that the video person was real, and mentalized that the person could see them or not. Pre‐recorded videos did not …

silmänliikkeetsykegenetic structuresPsykologia - Psychologymentalizingheart ratekatsementalisaatioeye contactkasvotgaze trackingskin conductance response
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Design and Characterization of Effective Ag, Pt and AgPt Nanoparticles to H2O2 Electrosensing from Scrapped Printed Electrodes

2019

The use of disposable screen-printed electrodes (SPEs) has extraordinarily grown in the last years. In this paper, conductive inks from scrapped SPEs were removed by acid leaching, providing high value feedstocks suitable for the electrochemical deposition of Ag, Pt and Ag core-Pt shell-like bimetallic (AgPt) nanoparticles, onto screen-printed carbon electrodes (ML@SPCEs, M = Ag, Pt or AgPt, L = metal nanoparticles from leaching solutions). ML@SPCEs were characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The results were compared to those obtained when metal nanoparticles were synthesised using standard solutions of metal salts (MS@…

silver nanoparticleshydrogen peroxide sensorMaterials sciencechemistry.chemical_element02 engineering and technologyScreen-printed electrodeslcsh:Chemical technologyElectrochemistryPlatinum nanoparticles01 natural sciencesBiochemistrySilver nanoparticleAnalytical Chemistryscreen-printed electrodesHydrogen peroxide sensorPlatinum nanoparticleslcsh:TP1-1185Química FísicaElectrical and Electronic EngineeringInstrumentationBimetallic nanoparticlesConductive inksbimetallic nanoparticlesMetals recovery010401 analytical chemistry021001 nanoscience & nanotechnologyconductive inksAtomic and Molecular Physics and Optics0104 chemical sciencesElectrochemical gas sensorDielectric spectroscopymetals recoverychemistryLeaching (metallurgy)Cyclic voltammetrySilver nanoparticles0210 nano-technologyPlatinumplatinum nanoparticlesNuclear chemistry
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Los sistemas alternativos y aumentativos de comunicación (SAAC) como instrumento para disminuir conductas desafiantes en el alumnado con TEA: estudio…

2017

Resumen Se describe una intervención, basada en el Programa de Habla Signada de Benson Schaeffer, para dotar de un Sistema Alternativo y Aumentativo de Comunicación (SAAC) a una niña de ocho años diagnosticada con trastorno del espectro autista (TEA). Se pretende que la alumna, mediante la utilización de signos, pueda expresar sus necesidades y disminuir las conductas desafiantes que propicia, ya que se estima que estas tienen una clara intención comunicativa. Se utiliza una metodología cualitativa de estudio de caso único y por objetivos. El programa se desarrolló en el aula de comunicación y lenguaje (CyL) de un centro público de educación infantil y primaria (CEIP) de la Comunidad Valenc…

sistema alternativo y aumentativo de comunicación.Language classroommedia_common.quotation_subjectComunicació oralPrimary educationcomunicaciónGeneral Medicinelcsh:Social Scienceslcsh:Hlcsh:H1-99Trastorno del espectro autistaGirllcsh:Social sciences (General)AutismePsychologyHumanitiesconductas desafiantesAugmentativemedia_common
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The role of adolescents' temperament in their positive and negative emotions as well as in psychophysiological reactions during achievement situations

2019

Abstract This study examined the role of adolescents' (n = 190) temperament in their emotional reactions in achievement situations. Adolescents rated their temperament (i.e., surgency/extraversion, negative affectivity, effortful control) and completed achievement tasks in Grade 6. They also reported their emotions before and during challenging and non-challenging tasks. In addition, adolescents' autonomic nervous system reactions (i.e., skin conductance levels) were recorded. The results showed that high effortful control was related to higher levels of positive emotions independent of the degree of task difficulty. Low negative affectivity and high effortful control were related to lower …

skin conductance levelSurgencySocial Psychologymedia_common.quotation_subjectNegative affectivityEducationDevelopmental psychologytemperamenttitunteetachievement emotionsDevelopmental and Educational Psychologyta5160501 psychology and cognitive sciencesta515media_commonExtraversion and introversionachievement situations4. Education05 social sciences050301 educationtemperamentlapsuusoppimispsykologiapsykofysiologiaadolescenceTemperamentSkin conductancePsychology0503 education050104 developmental & child psychologyLearning and Individual Differences
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A simple field method to measure the hydrodynamic properties of soil surface crust

2013

The hydraulic resistance of the surface crust was determined by a combination of two infiltrometric techniques: first, a surface measurement of steady-state infiltration rate is conducted by a mini-disk tension infiltrometer (MDI); then, the surface crust is removed, its thickness is measured, and a ponded infiltration test is performed at the same site. The Beerkan Estimation of Soil Transfer parameters (BEST) method is applied to estimate the hydraulic properties of the underlying soil provided the particlesize distribution and the bulk density are known. Under the assumption of a unit gradient of hydraulic head below the soil crust, the pressure head at the interface crust-soil is derive…

soil surface crust mini disk tension infiltrometer BEST procedureBEST procedure; Mini disk tension infiltrometer; Soil surface crust; Industrial and Manufacturing Engineering; Mechanical Engineering; BioengineeringWater flowMechanical Engineeringlcsh:SBioengineeringCrustInfiltration (HVAC)lcsh:S1-972Industrial and Manufacturing Engineeringlcsh:AgricultureHydraulic headSoil surface crustHydraulic conductivityMini disk tension infiltrometerSoil crustLoamSoil surface crust mini disk tension infiltrometer BEST procedure.InfiltrometerGeotechnical engineeringBEST procedurelcsh:Agriculture (General)MathematicsJournal of Agricultural Engineering
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