Efecto de la Aplicación del AIB (Ácido Indol Butírico) y Biol en el Enraizamiento de Estacas de Cedrón (Aloysia triphylla (L´Hérit) Britt) Chiguata. Arequipa. 2017

El trabajo de investigación se llevó a cabo, en el Campo Experimental del Instituto de Educación Superior (IES), de la “ONG El Taller Asociación de Promoción y Desarrollo” en el Distrito de Chiguata, Provincia y Región Arequipa. Geográficamente se halla en la Longitud 71° 24’ 01”, Latitud 16° 24’ 01” y 2 943 msnm. La investigación se centró en el estudio de los efectos de la aplicación del (AIB) ácido indol butírico y Biol en el enraizamiento de estacas de Cedrón (Aloysia triphylla (L’Hérit) Britt). Se consideró para Factor A (Numero de yemas) dos niveles, A1 (3 yemas) y A2 (4 yemas) y para Factor B (Enraizadores) 4 niveles, B1 (inmersión en Biol al 50% durante 24 horas), B2 (inmersión en Biol al 50% durante 48 horas), B3 (aplicación de Rapid root) y B4 (Sin Enraizadores). El Diseño experimental fue un Arreglo Factorial en Bloques Completos al Azar (BCA), (2x4) con ocho tratamientos y seis repeticiones. En los resultados obtenidos para Porcentaje de enraizamiento y Número de raíces destacó T1 (estacas de 3 yemas con inmersión en Biol al 50% durante 24 horas) con 80.16% y 8.08 unidades respectivamente. En Longitud de raíces sobresale estadísticamente estacas de 3 yemas con 10.99 cm. para Factor A y aplicación de Rapid root con 13.54 cm. para Factor B. En Número de brotes, destacó T7 (estacas de 4 yemas con aplicación de Rapid root) con 6.0 unidades. Palabras claves: Estacas, Biol, Rapid root.Tesi

Raising the Efficiency Limit of the GaAs-based Intermediate Band Solar Cell Through the Implementation of a Mololithic Tandem with an AlGaAs top Cell.

The high efficiency limit of the intermediate band solar cell (IBSC) corresponds to the case of using as intermediate band (IB) host material a semiconductor with gap in the range of 2 eV. Traditional photovoltaic materials, such as Si and GaAs, are not appropriate to produce IB devices because their gaps are too narrow. To overcome this problem, we propose the implementation of a multi-junction device consisting of an IBSC combined with a single gap cell. We calculate the efficiency limits using the detailed balance model and conclude that they are very high (> 60% under maximum concentration) for any fundamental bandgap from 0.7 to 3.6 eV in the IBSC inserted in the tandem. In particular, the two-terminal tandem of a GaAs-based IBSC current matched to an optimized AlGaAs top cell has an efficiency limit as high as 64%

Radiative thermal escape in intermediate band solar cells

To achieve high efficiency, the intermediate band (IB) solar cell must generate photocurrent from sub-bandgap photons at a voltage higher than that of a single contributing sub-bandgap photon. To achieve the latter, it is necessary that the IB levels be properly isolated from the valence and conduction bands. We prove that this is not the case for IB cells formed with the confined levels of InAs quantum dots (QDs) in GaAs grown so far due to the strong density of internal thermal photons at the transition energies involved. To counteract this, the QD must be smaller

Application of photoluminescence and electroluminescence techniques to the characterization of intermediate band solar cells

The intermediatebandsolarcell (IBSC) is a photovoltaic device with a theoretical conversion efficiency limit of 63.2%. In recent years many attempts have been made to fabricate an intermediateband material which behaves as the theory states. One characteristic feature of an IBSC is its luminescence spectrum. In this work the temperature dependence of the photoluminescence (PL) and electroluminescence (EL) spectra of InAs/GaAs QD-IBSCs together with their reference cell have been studied. It is shown that EL measurements provide more reliable information about the behaviour of the IB material inside the IBSC structure than PL measurements. At low temperatures, the EL spectra are consistent with the quasi-Fermi level splits described by the IBSC model, whereas at room temperature they are not. This result is in agreement with previously reported analysis of the quantum efficiency of the solarcell

Plan de Negocios para la Creación de una Empresa Procesadora de Piña en la Ciudad de Villaviencio, Meta.

98 (56) Hojas.Formular un plan de negocio para la ejecución y puesta en marcha de una empresa procesadora de piña en el Municipio de Villavicencio – Meta. • Identificar el mercado industrial para las conservas de piña en almíbar, así como las estrategias de mercadeo del producto final. • Elaborar un estudio técnico que permita la identificación del producto y los requerimientos para el desarrollo de la actividad, objeto del plan de negocio. • Diseñar el estudio administrativo definiendo misión, visión, objetivos, estrategias, estructura, costos administrativos y aspectos legales de la organización. • Determinar la viabilidad financiera del proyecto con un horizonte de 5 años.Resultado final para optar el título de Especialización en Gestión de Proyectos, Tesis (Especialización en Gestión de Proyectos) Universidad de los Llanos. Villavicencio - Meta 2019.EspecializaciónEspecializaciones en Gestion de Proyecto

A novel digital cognitive biomarker for mild cognitive impairment and Alzheimer disease

Recent evidence suggests that oculomotor behaviours linked to cognitive performance can be a biomarker of Alzheimer?s disease (AD). Short-Term Memory Binding (STMB) declines in patients with AD dementia and in those at risk of dementia. STMB relies on brain regions relevant to visual processing which are known to support oculomotor behaviours. Viewmind is proposed as a novel ?cognitive digital biomarker? with the potential of revealing phenotypic features of AD in the pre-dementia stage of the pathology. Viewmind applies artificial intelligence to analyse eye movements and pupil responses during the performance of STMBT.Fil: Fernández Gerardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Schumacher, Marcela Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Orozco, David. Clínica Privada Bahiense; ArgentinaFil: Sgrilli Gustavo. Clinica Privada Bahiense; ArgentinaFil: Echeverria Gustavo. Clinica privada Bahiense; ArgentinaFil: Linares Ramiro. Clinica Privada Bahiense; ArgentinaFil: Parra, Mario A. University of Strathclyde; Reino UnidoAlzheimer´s Association International ConferenceDenver, ColoradoEstados UnidosAlzheimer Associatio

Modelling and Characterization of Multiple Level Intermediate Band Solar Cell

Intermediate band solar cells (IBSCs) are a new kind of devices capable of surpassing the Shockley Queisser efficiency limit for conventional solar cells. This novel technology requires the use of a new type of material named intermediate band (IB) material which makes a better use of the solar spectrum thanks to the existence of a collection of electronic levels within the band gap of the semiconductor. Quantum Dots (QDs) remain as a feasible technology to implement IB materials. InAs/GaAs QD-IBSCs were manufactured in order to test the validity of the concept, although their real size and shape are far from the optimum. This causes extra electron levels to appear within the nanostructure confining potential, degrading the performance of the device. In this paper, the effect of these extra levels will be studied through a multiple level IBSC model based on the detailed balance, but modified so a term accounting for the non-radioactive recombination (NRR) is also included. The model is completed with constant fitting parameters so the concentration JL-VOC curves (which do not incorporate series resistance effects) can be fitted. Several QD-IBSCs where manufactured, measured and fitted with this model, rendering relevant information about the recombination nature of the QD-IBSC

Modeling and characterization of multiple level intermediate band solar cell

Intermediate band solar cells (IBSCs) are a new kind of devices capable of surpassing the Shockley Queisser efficiency limit for conventional solar cells. This novel technology requires the use of a new type of material named intermediate band (IB) material which makes a better use of the solar spectrum thanks to the existence of a collection of electronic levels within the band gap of the semiconductor. Quantum Dots (QDs) remain as a feasible technology to implement IB materials. InAs/GaAs QD-IBSCs were manufactured in order to test the validity of the concept, although their real size and shape are far from the optimum. This causes extra electron levels to appear within the nanostructure confining potential, degrading the performance of the device. In this paper, the effect of these extra levels will be studied through a multiple level IBSC model based on the detailed balance, but modified so a term accounting for the non-radiative recombination (NRR) is also included. The model is completed with constant fitting parameters so the concentration JL-VOC curves (which do not incorporate series resistance effects) can be fitted. Several QD-IBSCs where manufactured, measured and fitted with this model, rendering relevant information about the recombination nature of the QD-IBSCs

Demonstration of the operation principles of intermediate band solar cells at room temperature

In this work we report, for the first time at room temperature, experimental results that prove, simultaneously in the same device, the two main physical principles involved in the operation of intermediate band solar cells: (1) the production of sub-bandgap photocurrent by two optical transitions through the intermediate band; (2) the generation of an output voltage which is not limited by the photon energy absorption threshold. These principles, which had always required cryogenic temperatures to be evidenced all together, are now demonstrated at room temperature on an intermediate band solar cell based on InAs quantum dots with Al0.3Ga0.7As barriers

Realistic performance prediction in nanostructured solar cells as a function of nanostructure dimensionality and density

The behavior of quantum dot, quantum wire, and quantum well InAs/GaAs solar cells is studied with a very simplified model based on experimental results in order to assess their performance as a function of the low bandgap material volume fraction fLOW. The efficiency of structured devices is found to exceed the efficiency of a non-structured GaAs cell, in particular under concentration, when fLOW is high; this condition is easier to achieve with quantum wells. If three different quasi Fermi levels appear with quantum dots the efficiency can be much higher