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Experimental and Computational Study of the Effect of Temperature on the Electro-Polymerization Process of Thiophene  [PDF]
María Belén Camarada, M. Romero, M. C. Giménez, W. Schmickler, M. A. del Valle
Open Journal of Organic Polymer Materials (OJOPM) , 2013, DOI: 10.4236/ojopm.2013.33010
Abstract:

Temperature effect on the nucleation and growth mechanisms (NGM) of poly(thiophene) (PTh) was investigated through experimental and computational tools. The computational simulation method was based on a kinetic Monte Carlo algorithm. It reproduced key processes such as diffusion, oligomerization, and the precipitation of oligomers onto the electrode surface. Electrochemical synthesis conditions at temperatures between 263 and 303 K were optimized. The deconvolution of the i-t transients reflected two contributions: a progressive nucleation with three-dimensional growth controlled by diffusion and the other by charge transfer, PN3Ddif and PN3Dct, respectively. As temperature decreased, a diminution of the charge associated to each contribution was observed and the nucleation induction time increased. Experimental and computational evidence indicated that temperature does not change the nucleation and growth mechanism (NGM). This effect was ascribed to kinetic factors rather than to film conductivity. This work contrasts simulation and experimental evidence and demonstrates how computational simulations can help to understand the electrochemical process of conducting polymers formation.

Validación de un cuestionario para evaluar la seguridad del paciente en los laboratorios clínicos
Giménez Marín,ángeles; Rivas-Ruiz,Francisco; ,;
Gaceta Sanitaria , 2012, DOI: 10.1016/j.gaceta.2011.12.012
Abstract: objectives: the aim of this study was to prepare, pilot and validate a questionnaire to evaluate patient safety in the specific context of clinical laboratories. methods:: a specific questionnaire on patient safety in the laboratory, with 62 items grouped into six areas, was developed, taking into consideration the diverse human and laboratory contextual factors which may contribute to producing errors. a pilot study of 30 interviews was carried out, including validity and reliability analyses using principal components factor analysis and cronbach's alpha. subsequently, 240 questionnaires were sent to 21 hospitals, followed by a test-retest of 41 questionnaires with the definitive version. results: the sample analyzed was composed of 225 questionnaires (an overall response rate of 80%). of the 62 items initially assessed, 17 were eliminated due to non-compliance with the criteria established before the principal components factor analysis was performed. for the 45 remaining items, 12 components were identified, with an cumulative variance of 69.5%. in seven of the 10 components with two or more items, cronbach's alpha was higher than 0.7. the questionnaire items assessed in the test-retest were found to be stable. conclusions: we present the first questionnaire with sufficiently proven validity and reliability for evaluating patient safety in the specific context of clinical laboratories. this questionnaire provides a useful instrument to perform a subsequent macrostudy of hospital clinical laboratories in spain. the questionnaire can also be used to monitor and promote commitment to patient safety within the search for continuous quality improvement.
Modelos matemáticos a través de proyectos
Aravena, María;Caama？o, Carlos;Giménez, Joaquín;
Revista latinoamericana de investigación en matemática educativa , 2008,
Abstract: in this research we analyze the mathematical production of a group of secondary students when faced with the task of projects based on the modelization of situations. in the development and implementation of the didactic proposal several studies were considered that illustrated the benefits of introducing this type of work into the classroom as much to overcome obstacles and difficulties as to develop mathematical skills. in order to analyze students' production, the object of this case study, categories were designed to enable the evaluation of this methodology. on a results level, there is a manifest development of cognitive and metacognitive capacities and of transversal formation, in addition to an efficient performance in the utilization of concepts and mathematical processes.
Las 'villas de emergencia' como espacios urbanos estigmatizados
Mabel Nélida Giménez,María Elena Ginóbili
Historia Actual Online , 2003,
Abstract: En la última década, la mayoría de las ciudades de Argentina se desarrollaron de acuerdo a dos patrones: extensión territorial y segmentación interna. Los sectores de altos ingresos se aíslan voluntariamente en zonas periféricas exclusivas, en barrios autosuficientes, dotados de costosas viviendas, servicios, seguridad privada, etc. Los más carenciados se ubican también en la periferia pero en áreas de menor valor, conocidas con el nombre de "villas de emergencia" o "villas miseria", caracterizadas por un alto grado de precariedad y deficiente equipamiento social. El trabajo intenta reflexionar sobre las relaciones que se establecen entre estos espacios urbanos y las identidades de sus habitantes.
La globalización económica y la inversión extranjera directa en las regiones periféricas
María Emilia Estrada,Mabel Nélida Giménez
Historia Actual Online , 2008,
Abstract: En este artículo se presenta la incidencia que sobre las regiones periféricas del moderno sistema mundial tiene tanto la globalización económica como la inversión extranjera directa. Partiendo del estudio de caso de la Argentina en las últimas décadas del siglo XX, se comprueba la intensificación de la heterogeneidad en el desarrollo con la aceleración del proceso globalizador y qué responsabilidad tiene la IED (Inversión Extranjera Directa) en ello. Tras revisar el marco conceptual de la IED, se aborda la IED en la Argentina de los noventa y la IED en el ámbito local.
Quality and Applicability: Two Necessary Requirements in Instruments That Measure Creative Potential, for Use in the Classroom  [PDF]
Nazira Píriz Giménez, Joselín Cantero, Virginia Mallarini, Jerónimo Tucci, Diana Shablico, María Noel López Larrama
Creative Education (CE) , 2019, DOI: 10.4236/ce.2019.1013255
Abstract: Creativity is a growing demand in today’s world. Education for creativity takes hierarchy, as well as the search for ways to evaluate its promotion. This paper presents partial results of a research project aimed at the study of the promotion of creative qualities in science education. The CREA test was used as an instrument to evaluate the creativity of students. The results allow us to propose limitations of this test as a tool for a global measure of creativity. The conventional analysis could measure one of the creative qualities: fluidity. The assessment of other creative qualities could benefit from a modified analysis. Some modifications like test time, could improve the measure of flexibility and elaboration. The applicability of the CREA test may not be accompanied by quality to the extent of creative potential.
Obtención de la máxima potencia en paneles fotovoltaicos mediante control directo: corriente a modulación por ancho de pulsos
Herman,Fernández; Martínez,Abelardo; Guzmán,Víctor; Giménez,María Isabel;
Universidad, Ciencia y Tecnología , 2006,
Abstract: este trabajo contempla el dise？o y la implementación de un circuito sencillo y de bajo costo para aprovechar la potencia máxima generada por paneles fotovoltaicos. el dise？o basado en el lm3524, reúne las condiciones propicias de un sistema colocado en sitios rurales y de difícil acceso. el sistema de control obtiene en todo momento la potencia generada por los paneles fotovoltaicos mediante la medición de corriente producida. además, valiéndose de una red sencilla de medición de voltaje, limita el voltaje de salida cuando se usan baterías como elementos de carga. se realizaron pruebas experimentales utilizando distintos tipos de cargas y provocando perturbación en celdas de un de los paneles solares para demostrar la capacidad de seguimiento del controlador. los resultados confirman una respuesta satisfactoria del dise？o.
Modelo genérico de celdas fotovoltaicas
Fernández,Herman; Martínez,Abelardo; Guzmán,Víctor Manuel; Giménez,María Isabel;
Universidad, Ciencia y Tecnología , 2008,
Abstract: this work presents the modeling and the simulation in pspice of a circuit that has the electric behavior of a solar panel. the model allows for the selection of a circuit representing a single cell or multi cell arrays connected in serie and parallel. model evaluation is done using a computational tool that can input parameters related to the number of cells connected in the different serie-parallel combinations, the single cell resistances, a dimension-less parameter for open circuit tuning and the short circuit current. the model automatically calculates the serie and parallel resistance when working with complex circuits in a solar panel array. tuning the above mentioned parameters the voltage and current characteristic curves of commercially available solar cell arrays are obtained. model application is restricted to photovoltaic cells under the same solar radiation since the shadow effect over different cells is not considered. the results obtained in the simulation prove the model's good performance, making it useful in the simulation of photovoltaic systems with solar cells, battery banks and energy conversion circuits.
Simulación mediante pspice de un modelo simplificado y de alta eficiencia de una batería de plomo - ácido
Fernández,Herman; Martínez,Abelardo; Guzmán,Víctor; Giménez,María;
Universidad, Ciencia y Tecnología , 2009,
Abstract: a new lead-acid battery model is presented, with a reduced component count, lower processing time, high efficiency, able to parametrize the charge and discharge resistances and easily adaptable to other simulation platforms. to prove the model, an external supply is used to evaluate the charge and discharge operating modes. the simulated test shows the satisfactory model response in the charge and discharge modes, with over 90% efficiency. furthermore comparisons are made with other models, underlaying its advantages and disadvantages.
Categorización de las revistas espa olas de Ciencias Sociales y Humanas en RESH
Alcaín Partearroyo, María Dolores,Román Román, Adelaida,Giménez Toledo, Elea
Revista Espa？ola de Documentación Científica , 2008,
Abstract: The aim of this note is to communicate and explain the last additions included in the RESH website: an integrated evaluation system based on a diverse range of indicators on editorial quality, peer review, international visibility and impact index. The team developing RESH has been working on establishing a weighted system. This system assigns a different weight for each type of indicator thus enabling the construction of a journal ranking in each discipline or in each sub-discipline. Evaluators, authors or editors can find, in the cited website, the position of each journal in the context of its subject area, and the data justifying the final position of each journal. El propósito de esta nota es comunicar y explicar las últimas mejoras incorporadas a la plataforma RESH, sistema integrado de evaluación que se basa en diversos tipos de indicadores de calidad en relación con el proceso editorial, la revisión por pares, la visibilidad internacional y los índices de impacto. El grupo que desarrolla RESH ha estado trabajando en la puesta a punto de un sistema de baremación que adjudica diferente peso a los indicadores que miden los diferentes aspectos de la calidad, con objeto de poder construir listas jerarquizadas (ranking) de las revistas en el contexto de sus disciplinas y/o de sus áreas del conocimiento. A partir de ahora, evaluadores, autores y editores podrán encontrar en RESH la posición que ocupa cada revista en el contexto de su especialidad, así como los datos que dan origen a la posición final alcanzada por cada revista.
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