108 research outputs found
La protección internacional de las minorías religiosas: Algunas consideraciones en torno a la declaración de los derechos de las personas pertenecientes a minorías y al Convenio-Marco sobre la protección de las minorías
La asistencia religiosa en el derecho concordatario.
Material incluido en el volumen especial de la revista del Instituto Martín de Azpilcueta, Universidad de Navarra : Ius Canonicum (1999), en honor de Javier Hervada
Small Projects: A Method for improving Learning.
Ideas concerning problem-based learning (PBL) developed after running different experiences in different Spanish Universities, are discussed. The driver for introducing PBL has been the requirement for studying Mathematics by the Engineering students. A methodology hybrid of problem-based learning for Mathematics in Engineering studies is proposed. The model is a combination of formal lectures, practical and laboratory sessions with autonomous small projects
LA FORMACIÓN DE LA HABILIDAD PARA RESOLVER PROBLEMAS DE
El siguiente artículo muestra los resultados de una experiencia pedagógica sobre el desarrollo de habilidades en la resolución de problemas de matemáticas en estudiantes de primer año. La investigación se llevó cabo en el Departamento de Matemáticas de la Universidad de Matanzas, Cuba. Basado en el enfoque histórico cultural de L. S. Vygotsky, el trabajo presenta una nueva visión de la educación como desarrollo integral de la personalidad, que tiene lugar mediante la interacción social, la actividad conjunta y las relaciones entre profesor-estudiantes-conocimientos matemáticos, que se integran en la noción de enseñanza-aprendizaje que sustentamos. Con la investigación realizada durante varios cursos se ha logrado que los estudiantes desarrollen las acciones relacionadas con la resolución de problemas de matemáticas. En las conclusiones se enumeran los avances obtenidos hasta el momento
Novel, simple, and environmentally safe method for wastewater pollutant removal
In this work, a new methodology has been developed for the elimination of cobalt, nickel and a mixture of both metals from synthetic wastewater in a continuous way. This methodology consists of the electrochemical formation of ferrites of these metals through the oxidation of iron sheets and the reduction of water. Two critical process parameters, current densities and initial pollutant concentration, were analysed. An initial batch prototype resulted in efficiencies on the order of 98% under conditions of applied densities of 50 mA/cm2 and concentrations of both metals of until 100 ppm of the ions. The obtained particles have been characterized by X-ray diffraction to determine the formation of ferrites without the appearance of secondary phases. The formed particle sizes are approximately 30 nm, with hemispherical or flower-like shapes. A flow system prototype was designed for the recirculation of the solution with 100 ppm of both contaminating metals, obtaining approximately 90% recovery with an easy magnetic harvesting. © 2021 The Author
Un Modelo de Curso Integrado de Cálculo en una Variable.
El reto del Espacio Europeo de Educación Superior, que pretende unificar los estudios de los países miembros de la Unión Europea, ha puesto de manifiesto la posibilidad de usarlas técnicas de enseñanza no presencial como un canal más de transmisión del conocimiento para ser usado, en mayor o menor medida, junto con la enseñanza “más tradicional”. Ello nos permite diseñar un curso de Cálculo que aglutine los aspectos tradicionales (clases magistrales y de problemas) de la enseñanza de las matemáticas con las nuevas tecnologías (uso de paquetes de Cálculo Simbólico, webs interactivas, libros electrónicos, applets, etc.). Esto nos permitirá por un lado profundizar en determinados conceptos matemáticos y por otro la resolución de problemas “reales” y no problemas docentes y preparados, que son los únicos que pueden resolverse por los métodos tradicionales
Could it be possible to replace DERIVE with MAXIMA?
In recent years, a considerable number of teachers in Spain have been using DERIVE to teach math subjects in High Schools and Universities. This software has been used by the authors of this work as a support tool in Mathematics courses for Engineering. Since Texas Instruments does not support DERIVE, we were faced with finding an alternative software product, and considering the possibility of using a public-domain software such as MAXIMA. Here we make a comparative study of DERIVE and MAXIMA as support tools for a Calculus course for first year Engineering students
Novel, simple, and environmentally safe method for wastewater pollutant removal
In this work, a new methodology has been developed for the elimination of cobalt, nickel and a mixture of both metals from synthetic wastewater in a continuous way. This methodology consists of the electrochemical formation of ferrites of these metals through the oxidation of iron sheets and the reduction of water. Two critical process parameters, current densities and initial pollutant concentration, were analysed. An initial batch prototype resulted in efficiencies on the order of 98% under conditions of applied densities of 50 mA/cm2 and concentrations of both metals of until 100 ppm of the ions. The obtained particles have been characterized by ꭕ-ray diffraction to determine the formation of ferrites without the appearance of secondary phases. The formed particle sizes are approximately 30 nm, with hemispherical or flower-like shapes. A flow system prototype was designed for the recirculation of the solution with 100 ppm of both contaminating metals, obtaining approximately 90% recovery with an easy magnetic harvestingThis research was funded by the Spanish Ministry of Science, Innovation, and Universities under projects PGC2018-095642-B-I00 and PGC2018-096016-B-I00. L.G. acknowledges financial support from the Ramón y Cajal program (RYC-2014-15512). E. Mazario. acknowledges financial support from the Madrid Government (Comunidad de Madrid Spain) under the Multiannual Agreement with Universidad Autonoma de Madrid in the line of action encouraging youth research doctors, in the context of the V PRICIT (Regional Programme of Research and Technological Innovation), (SI1-PJI-2019-00366). L. Duque acknowledges for the contract obtained from Ayudas para la contrataciónde ayudantes investigación y técnicos de laboratorio of Comunidad Autónoma de Madrid. The authors would like to acknowledge the use of the Advanced Microscopy Laboratory (INA-Universidad de Zaragoza) for access to their instrumentation and expertis
Ofloxacin degradation over nanosized Fe3O4 catalyst viathermal activation of persulfate ions
In this work, an Fe3O4 catalyst was synthetized in a single step via electrochemical synthesis. The Fe3O4 catalyst was used to evaluate the degradation of Ofloxacin (OFX) using a heterogeneous advanced oxidation process with sodium persulfate (PS). PS activation was successfully achieved via thermal conventional heating directly and subsequently applied for the degradation of OFX. The degradation kinetics were studied under different conditions, such as catalyst and oxidant concentration and temperature. The results show that a higher reaction temperature, catalyst and initial PS dose strongly influence the degradation efficiency. Thermal activation of persulfate was tested at 20, 40 and 60 °C. At 60 °C, the half-time of OFX was 23 times greater than at 20 °C, confirming the activation of persulfate. Mineralization studies also showed that under optimized conditions (20 mM of persulfate, 1 g/L catalyst and 100 mg/L OFX), a 66% reduction in organic matter was observed, in contrast to that obtained at 40 °C and 20 °C, which was null. The reusability, as tested through the fourth reuse cycle, resulted in a 38% reduced degradation efficiency when comparing the first and last cycle. Furthermore, the electrosynthesized catalyst presented similar degradation efficiencies in both real water and MilliQ, mainly because of the (Formula presented.) generation at high (Formula presented.) concentrations that takes place in (Formula presented.) contaminated waterThis research was funded by the Madrid Government (Comunidad de Madrid-Spain)
under the Multiannual Agreement with Universidad Autónoma de Madrid in the line of action
encouraging youth research doctors, in the context of the V PRICIT (Regional Programme of Research
and Technological Innovation), (SI1-PJI-2019-00366), and by the Spanish Ministry of Science and
In-novation under project no. PID2021-123431OB-I0
Electrofenton with reticular vitreous carbon and iron oxide nanoparticles for dye removal: a preliminary study
In this work, an RVC electrode coated with magnetic iron oxide nanoparticles was used for the degradation of methylene blue as a model dye. The electrofenton process was carried out by the reduction of oxygen dissolved in the electrolyte on the modified RVC electrode to produce hydrogen peroxide. The presence of the magnetite/maghemite nanoparticles in the structure produces the formation of OH∙ radicals that oxidize methylene blue. The RVC/coated was prepared by two different methodologies: Methodology A: by immersion of the electrode in a solution saturated with magnetite nanoparticles; and Methodology B: by electrochemical synthesis. Scanning electron microscopy, X-ray diffraction and Mössbauer spectroscopy shows a uniform coating of the electrode. The Mössbauer spectroscopy determines the only presence of maghemite using methodology A and the presence of 60% of magnetite and a 40% of maghemite when methodology B was used. The dipping methodology is the one that has provided the best results in the electrofenton degradation of methylene blue, obtaining a 100% removal after 35 min, applying a current of 100 mA in a 20 mg L−1 solution of methylene blue, and a concentration of 50 mM sodium sulfat
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