1,884 research outputs found
Nueva cita de "Sporobolus indicus" (L.) R. Br. (Poaceae) en Andalucía occidental
A new record of Sporobolus indicus (L.) R. Br. (Poaceae) in Western AndalusiaPalabras clave. Sporobolus, Poaceae, corología, Córdoba, Andalucía Occidental, Península Ibérica.Key words. Sporobolus, Poaceae, chorology, Córdoba, Western Andalusia, Iberian Peninsula
The impact of E-learning and ICT on English language learning: COVID-19 context
Background: E-learning and ICT have developed an innovative way of teaching English. To make sure the learning of this foreign language is effective, educational establishments and universities adjusted their infrastructure and technological devices. Aim: This article aims to present the results from a comprehensive examination of the literature regarding the Effects of E-learning and ICT on English language learning in COVID-19. Methods: The investigators made use of the PRISMA MODEL to determine the 65 articles to be included in the sample selection. A systematic search was performed on databases to select articles on E-learning and ICT related to English language learning. The databases employed for this study were Scielo, Redalyc, Dialnet, cademic Publishing (ACPI), Springer, Scopus, ECLAC, and MINTIC. Results: These technologies experienced an increase in usage during the COVID-19 pandemic. Conclusion: Incorporating e-learning and ICT has made language learning more dynamic. In addition, it demanded training of teachers to manage the tools and resources that they offer
Synthesis and reactivity of N-alkyl-2-oxoalkanesulfonamides
A series of N-alkyl-2-oxoalkanesulfonamides have been synthesized by reacting silyl enol ethers with N-alkyl-sulfamoyl chlorides. Their reactivity towards electrophiles was investigated in order to explore the regio-and stereoselectivity of the process. 2-Oxoalkanesulfonamides were used to prepare 5-(methylsulfamoyl)-1,4-dihydropyridines derivatives
Introducción
A partir de un convenio entre las sociedades española y cubana de cardiología y de sus respectivas revistas, se ha decidido realizar este suplemento especial, dedicado íntegramente a la prevención y la rehabilitación cardiovascular, publicado al unísono por ambas revistas y con la participación de prestigiosos especialistas de ambas sociedades.Este suplemento debe ser un referente para el trabajo cooperativo entre sociedades y entre revistas que, con la adecuada selección de temas de necesario interés e impacto en la morbimortalidad de las enfermedades cardiovasculares, permita establecer pautas para su abordaje
A new approach to the synthesis of 2-aminoimidazo[1,2-a]pyridine derivatives through microwave-assisted N-alkylation of 2-halopyridines
A microwave (focused waves) assisted N-alkylation of 2-halopyridines provides a convenient entry to 2-amino-imidazo[1,2-a]pyridine derivatives after reaction of the alkylated substrates with cyanamide under basic conditions.CDTI program (Plan concertado 96/0036)PROFARMA program (Ministerio de Industria y Ministerio de Sanidad
Short synthesis and anti-rhinoviral activity of imidazo[1,2-a]pyridines: the effect of acyl groups at 3-position
Various 2-amino-3-acyl-6-[(E)-1-phenyl-2-N-methylcarbamoylvinyl]-imidazo[1,2-a]pyridines, structurally related to Enviroxime were prepared to determine the effect of acyl groups on the antirhinoviral activity. A short and efficient means for the construction of the imidazo nucleus as well as biological evaluation of the final compounds are disclosed.This research was supported by a CDTI program (Plan concertado 96/0036)
and the Spanish Farma III programme (Ministerio de Industria y Ministerio de Sanidad). We are also
grateful to the Lilly Rhinovirus Action Group for their advice and interest in this work
An integrated tool for assessing the demand profile flexibility
The purpose of this paper is to describe an integrated
tool whose aim is to assess the residential demand profile flexibility
through the control of space conditioning loads, mainly air
conditioner and heat pump appliances. This assessment has been
divided into two principal tasks—an estimation of the controllable
load and a selection of the optimum load control strategy according
to a target profile and a set of prefixed constraints. The tool also
provides the aggregated load behavior, allowing a comparison between
different load strategies.
This tool can be applied from the customer’s and the utility’s
side. An application example to a real environment is also presented.This work was supported by the Ministerio
de Ciencia y Tecnología of Spain through Research Project DPI2001-
2779-C02-01
Electrical thermal storage modeling: a tool to valuate new opportunities and bids for residential users in a deregulated market
The purpose ofthis paper is to describe a useful tool for the initial analysis to assess the possibilities of residential Electric Thermal Storage (ETS), taking into account heat storage and cool storage devices. These load models are based on an energy balance between the indoor environment, the dwelling constructive parameters, the ETS device and the internal mass through a discrete statespace equation system. The main application of this load model has been oriented towards the simulation of ETS performance in order to evaluate the possibilities of Load Management in the new de-regulated structures of Electrical Power Systems. The proposed model has been implemented and validated for heat storage, using real data collected during the last years in residential areas to evaluate its accuracy and flexibility. Finally, a simulation case study is presented to show the possibilities of modifying the actual residential demand profile through a storage period re-scheduling proposed by the authors, taking into account the customer minimum comfort levels and avoiding program rejection.The work described in this paper is financially supported by the Ministerio de Ciencia y Tecnologia of Spain, through a research project (Ref. DP12001-2779-C02-01). The authors are very grateful to the Spanish company Gabarrón-Elnur S.A. for the generous cession of its commercial ETS appliances in order to test them and for its support to this research
A novel low-pass filter based on dielectric impedance inverters to enhance the multipactor breakdown threshold
This work presents a novel low-pass filter based on using dielectric materials, in the critical areas of the structure, to prevent high-power space condition adverse effects, like multipactor breakdown. It is shown that the use of dielectric pieces in the inverters of the filter leads to increased gaps between metallic parts in the irises. In addition, by completely filling up the air space in critical gaps, the multipactor breakdown thresholds can be increased. Moreover, they also lead to a volume reduction, increasing compactness of the structure. To demonstrate the proposed concept, a prototype has been manufactured with an aluminum housing and a Teflon dielectric material, and tested for multipactor effect at ESA-VSC Laboratory. Tests confirmed that the manufactured filter has good electrical performance with cut-off frequency 13.6 GHz, insertion losses 0.32 dB, return losses better than 15 dB, and additionally does not show multipactor breakdown up to the maximum power tested in the experimental facility (5.5 kW).This research work has been financially supported by the Spanish Ministerio de Ciencia e Innovación in the frame of the project “Green an Efficient Technologies for Advanced Telecommunication Systems (GRETAS)” with Ref. TPID2019-103982RB-C42
Adiciones y revisiones al Atlas de la flora vascular silvestre de Burgos, VII
Se mencionan 73 táxones con citas y/o comentarios referidos a su existencia
en la provincia de Burgos. De ellos 13 suponen una novedad para el catálogo provincial
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