Desarrollo de nuevos electrólitos poliméricos para baterías recargables tipo ion sodio y su uso potencial en el almacenamiento de energías renovables

Es posible sintetizar y caracterizar el IL Bis(triflourometanosulfonil)imida de trimetil sulfonio (M3STFSI). Se demostró mediante XRD y espectroscopía RAMAN que el IL cuenta con señales de difracción más intensas siendo un material más cristalino que sus precursores M3SI y LiTFSI así como un nuevo espectro RAMAN no reportado. Se preparó y caracterizó con éxito un electrolito tipo ternario (M3STFSIPEO-NaCIO4) obteniendo resultados prometedores, tal es el caso de la mezcla molar 12:3:1. Se descubrió que a mayor contenido de NaClO4 y menor contenido de PEO los electrolitos tipo ternarios son menos homogéneos por lo que en el análisis por DSC aparece más de un punto de fusion para las PEM de ACP. Se comprobó que a mayor contenido de IL los Tm de las PEM son más parecidas a los resultados obtenidos del mismo IL, así como encontrar las Tg a los -32°C aprox. Se obtuvieron resultados positivos a temperatura ambiente en las pruebas de conductividad (x10-3 Scm-1 ), lo cual es prioridad para el úso de las PEM como aplicación en baterías tipo ion sodio altamente comparable con lo ya reportado en la literatura (ver Tabla 5). Se explicaron las diferencias entre las bandas caracteristicas de las PEM por FTIR y RAMAN tal es el caso del nuevo IL que en el interval de frecuencia de 3050-2800 cm-1 muestra una señal que corresponde al enlace C-H del M3STFSI (C5H9F6NO4S3). Se obtuvieron los difractogramas de los precursores de las PEM así como de las 9 mezclas donde las de ACP resultaron ser las más amorfa

Understanding Assessment Processes for Communicative Competence through an Analysis of Teachers’ Reported Practice

This research addresses the types of assessment tasks, the assessment criteria, instruments and procedures of communicative competence used by primary school teachers in Andalusia. This multiple-case study drew on the experiences of teachers from four schools in the south of Spain. The data source has been the focus groups in which the teachers took part. The transcripts were analysed thematically by three researchers who devised a system of categories designed through an iterative process. The findings reveal the paucity of tasks used to assess reading, listening and oral expression. The study also shows the diverse problems faced by teachers when it comes to evaluating communicative competence. This paper highlights the need to rethink the curricular contents and the methods applied to assess communicative competence in primary schools

El turista cultural en ciudades patrimonio de la humanidad de Latinoamérica. El caso de Cuenca (Ecuador)

Heritage tourism, understood as the visit to places where culture and the historical-artisticheritage is remarkable, is becoming an important economic engine for those destinations.Especially, if they are recognized as a World Heritage Site by UNESCO. This paper presents an inquiring study that analyzes the profile of the cultural tourist, the characteristics of his trip and what are the main reasons for visiting a World Heritage City in South America, such as the city of Cuenca (Ecuador). The methodology used in this research consisted of a field work, based on surveys of tourists in the time they were visiting the city, between October 2014 and February 2015, applying a descriptive statistical analysis, a factorial analysis and by clusters of the sample. The results confirm an interesting typology of tourists with an educational level and a medium-high income and with a diversity of countries of origin. Likewise, it is evident that there are three motivational dimensions that induce to visit Cuenca: a cultural dimension, a circumstantial dimension and a dimension of convenience. It has been determined four types of visitors, being the tourist with cultural motivations the best satisfaction when visiting the city. The main practical application of this research is to contribute to understand the characteristics of tourists visiting a heritage city and what are their motivations, in order to segment the market and design tourism and cultural products that better meet their needs.El turismo cultural, entendido como la visita a lugares donde la cultura y el patrimonio histórico-artístico son destacables, se está convirtiendo en un motor económico importante para esos destinos, especialmente si han recibido el reconocimiento de Patrimonio Mundial por la UNESCO. Este artículo presenta un estudio indagatorio que analiza el perfil del turista cultural, las características de su viaje y cuáles son las principales motivaciones que hacen visitar una ciudad patrimonio de la humanidad en Suramérica, como es la ciudad de Cuenca (Ecuador). La metodología utilizada en esta investigación ha consistido en la realización de un trabajo de campo basado en encuestas a los turistas en el momento en que se encontraban visitando la ciudad, entre octubre de 2014 y febrero de 2015; se aplicaron un análisis estadístico descriptivo, un análisis factorial y por conglomerados sobre la muestra. Los resultados confirman una interesante tipología de turista con un nivel educativo alto, con una renta media-alta y con diversidad de países de procedencia. Así mismo, se evidencia que existen tres dimensiones motivacionales que inducen a visitar Cuenca: una dimensión propiamente cultural, otra circunstancial y una más de conveniencia. Se han determinado cuatro tipologías de visitantes, siendo el turista con motivaciones culturales el que mejor satisfacción tiene al visitar la ciudad. La principal aplicación práctica de esta investigación es contribuir a comprender las características de los turistas que visitan una ciudad patrimonial y cuáles son sus motivaciones, a efectos de segmentar el mercado y concebir productos turísticos y culturales que satisfagan mejor sus necesidades

Relevancia y eficiencia de las instituciones de educación superior privadas Zacatecas ¿Una educación de calidad?

Van casi tres décadas que la educación superior privada nace y se expande con una velocidad vertiginosa. No obstante su acelerado crecimiento se acompaña de una crisis de legitimidad debido a la escasa correspondencia de su oferta académica con las necesidades del entorno; por ende, de una cuestionable calidad educativa. En este siglo XXI, la educación superior en general se halla en un escenario de fortísimas tensiones que parecen no disiparse con el tiempo. Justo ahí, debe observarse con especial cuidado el desempeño de la universidad privada, que si bien es cierto, en un principio se le concibió como un fenómeno de aniquilación a la escuela pública por la ventaja de una supuesta educación de calidad; desde su masificación y diversidad de profesiones ha sido objeto de críticas insoslayables. La educación privada se ha dejado seducir por la educación neoliberal, por ello, más que responder a las necesidades sociales, reproduce fielmente los intereses del mercado laboral. En ese contexto, la educación privada de nivel superior en Zacatecas nace y se expande gradualmente desde 1985, existiendo en la actualidad más de 11 planteles de este sector. Sin embargo, muy pocas han alcanzado la reputación académica en virtud de pertenecer a una red nacional de campi; otras, se encuentran en la lucha por concentrar una matrícula que les asegure su permanencia en el Estado

Sizing methodology for photovoltaic systems considering coupling of solar energy potential and the electric load: dynamic simulation and financial assessment

A reliable methodology for the dimensioning of photovoltaic systems is presented in this paper. This method generates technical-financial variables that aid in the choice of the most adequate photovoltaic power system for each project. The techniques that are usually used determine the size of PV power plants considering the monthly average of the solar energy potential of the month with the lowest solar radiation and the electricity to be supplied to satisfy the demand. These conventional techniques generate an uncertainty of at least 40 %, mainly due to the daily dispersion of the solar energy availability and of the electric load. The proposed methodology takes into account a region’s own photovoltaic energy potential and the detailed characteristics of the electric load, matching both with different PV power plants sizes, and analyzing the whole during a time period that guarantees the reliability of the results. The energy coupling is performed integrating the energy parameters (solar energy and electric load) in short time intervals (30 minutes maximum) to determine the supplied energy, the unsupplied energy demand and the unused solar energy. The daily integration of the three factors, using a dynamic simulation and performing a financial evaluation, allows for the identification of the most appropriate PV power plant size for every project. The results indicate that this methodology reduces the uncertainty of the solar power-electric load coupling from 40 % to 2.2 %, which allows a better definition of the financial variables that determine the most appropriate installed solar power for a photovoltaic project.Campus Arequip

Solar thermoelectric cooling technology applied to transport of vaccines in isolated communities

Solar thermoelectric cooling technology applied to transport ofA thermoelectric cooling system supplied by photovoltaic solar energy was built and evaluated with different thermal loads. The thermoelectric cooling module consumes 70 W, it is supplied by a photovoltaic system of 90 W and 40 Ah battery. The voltage and electrical current in each component (panels, battery, and electric charge) has been measured. The tests were performed with different thermal loads placed in glass containers used for vaccines. To analyze the cooling and preservation process, the experiments were started at room temperature. The results show that the thermoelectric cooling system works for small thermal loads, and it could be applied to transport vaccines in isolated areas where people carry medicines in small containers that do not maintain the temperature necessary for the conservation of vaccines. vaccines in isolated communities.Campus Arequip

GASTRONOMIC PERCEPTION AND MOTIVATION OF A TOURISTIC DESTINATION: THE CITY OF QUITO, ECUADOR

The segmentation of intenational tourists who visit the city of Quito according to their perceptions with regard to the gastronomy. To achieve this objective, the methodology used in this investigation has been the application of a multivariate technique of item grouping and the realization of an univariate ANOVA post hoc analysis. The main conclusions that emanante from this research focus on the segmentation of international tourists into three different groups and in how the attraction to the gastronomy, considered by the travellers implies a greater satisfaction of the destination. The main practical implications are centred on a better understanding of key factors about how gastronomy can reinforce a touristic destination and achieve a greater satisfaction considered by the traveller

Telemedicine Strategy for CPAP Titration and Early Follow-up for Sleep Apnea During COVID-19 and Post-Pandemic Future.

WiththeacutefirstwaveoftheCOVID-19pandemicover,1thelongwaitinglistforsleeptestsforOSAmanagementhasbeenfurtherincreased.2,3ThenewpreventivehealthmeasuresagainstCovid-19implythatpatientsgotothehealthcentersaslittleaspossible,whichiswhyitisnecessarytoimplementandstartupatelematicworkflowwithhomestudiestoguaranteesleeptests,4especiallyCPAPtitration.5-8WeaimedtotestanewtelematicworkflowtodeliverCPAPtherapytoOSApatientsandtoevaluateitintermsofCPAPcompliance,costs,residualevents,symptomsandsatisfactionofpatients.Theusualtitrationstrategyhasthefollo-wingsteps.Thepatientisscheduledtothedaytime-hospitalforinformation,andeducationalandpracticaltrainingsessionwiththedevice(45min).Then,ourCPAPequipmentisdeliveredtohim/herforhometitration(tobereturnedthenextday),thedataisdownloaded,andafixedpressureisprescribed.Iftheregistra-tionisincorrect,thetitrationisrepeatedanotherday.Finally,thepatientisscheduledbytheservicecompanyprovidingCPAPequip-mentthatinformsagainhowtheequipmentworks,selectsafinalmaskfortreatment,andgiveashortpracticalsessionoftheCPAPuse

Experimental study of a photovoltaic direct current water pumping system for irrigation in rural-isolated Region of Arequipa, Peru

In the present experimental study, a photovoltaic (PV)-powered system in continuous current (4 kW) for the pumping of water in an isolated, rural agricultural zone in Arequipa—Peru was analyzed. A meteorological station was installed in the studied zone, measuring solar radiation, temperature, relative humidity, and wind speed. The electrical and hydraulic parameters of the solar-pumping system (i.e., electric current, voltage, mass flow, and hydraulic pressure) were measured in order to evaluate the efficiency of the energy transformation processes. The results indicate that, during the year of 2017, the PV pumping system in direct current (DC) functions from 07 h 30 min to 15 h 30 min, during an average of 8 h a day. The PV array, hydraulic, and global efficiencies were evaluated. This allows for the interpretation of efficiency independent of solar irradiance. The efficiency of the PV array and global efficiency remained constant (11.5% f and 8.5%, respectively). The functioning interval of the PV array ranges from 880 W up to 3400 W, making evident the versatility of the system of generation and consumption in DC, which is able to function since solar irradiance is at least 200 W/m2, corresponding to 880 W of PV array power, 27 m of total dynamic head (TDH) and 2 kg/s of mass flow,and 70% hydraulic efficiency. With greater mass flows (6.3 kg/s), the PV array power was 3256 W with a hydraulic efficiency of 55%, a TDH of 30 m, and a peak solar irradiance of 1190 W/m2. When the whole system functions in DC, the efficiencies are superior to those of systems, which operate with DC/alternating current (AC) current invertersrevisión por paresCampus Arequip