Conocimiento didáctico del contenido curricular en la enseñanza de la cantidad de sustancia y MOL

Se presentan los resultados de una investigación de los años 2007-2008 en la Universidad Pedagógica Nacional en Bogotá. Se determinaron las características del conocimiento didáctico del contenido curricular (CDCC) del profesorado de educación media del colegio el Jazmín, al diseñar currículos para enseñar los conceptos de cantidad de sustancia y mol. En esta caracterización predominó en el diseño, la no integración de los componentes del CDCC. Se describió además, si sus concepciones eran del modelo atomista o equivalentista, encontrándose explicaciones atomistas macroscópicas. Se desarrolló una Trama Histórica / Epistemológica (THE) sobre estos modelos teóricos y una Unidad Didáctica (UD) para enseñar dichos conceptos, la cual permitió evidenciar la complejización del modelo atomista. Este trabajo fue parte del proyecto DQU-025-07

Determination of the influence of specific building regulations in smart buildings

The automation of domestic services began to be implemented in buildings since the late nineteenth century, and today we are used to terms like ‘intelligent buildings’, ‘digital home’ or ‘domotic buildings’. These concepts tell us about constructions which integrate new technologies in order to improve comfort, optimize energy consumption or enhance the security of users. In conjunction, building regulations have been updated to suit the needs of society and to regulate these new facilities in such structures. However, we are not always sure about how far, from the quantitative or qualitative point of view, legislation should regulate certain aspects of the building activity. Consequently, content analysis is adopted in this research to determine the influence of building regulations in the implementation of new technologies in the construction process. This study includes the analysis of different European regulations, the collection and documentation of such guidelines that have been established and a study of the impact that all of these have had in the way we start thinking an architectural project. The achievements of the research could be explained in terms of the regulatory requirements that must be taken into account in order to achieve a successful implementation of a home automation system, and the key finding has been the confirmation of how the design of smart buildings may be promoted through specific regulatory requirements while other factors, such as the global economic situation, do not seem to affect directly the rate of penetration of home automation in construction

Development of a new glass–ceramic by means of controlled vitrification and crystallisation of inorganic wastes from urban incineration

This paper reports the results of a study of the feasibility of recycling the solid residues from domiciliary waste incineration by producing a glass-ceramic. The major components of the raw material (TIRME F+L), which was from a Spanish domiciliary incinerator, were CaO, SiO2 and Al2O3 but nucleating agents, such as TiO2, P2O5, and Fe2O3 were also present in reasonable amounts. It was found that a relatively stable glass with suitable viscosity could be obtained by mixing 65 wt% TIRME F+L with 35 wt% glass cullet. The heat treatment required to crystallise the glass produced from this mixture, designated TIR65, was nucleation at 560°C for 35 min followed by crystal growth at 100°C for 120 min. The resulting glass-ceramic contained a number of crystalline phases, the most stable being clinoenstatite (MgSiO3), or perhaps a pyroxenic phase which incorporates Ca, Mg and Al in its composition, and åkermanite (Ca2MgSi2O7). The microstructure contained both fibre-like and dendritic crystals. The mechanical properties were acceptable for applications such as tiles for the building industry.Peer reviewe

Simple theoretical proposal of the dependence of the deGennes extrapolation parameter with the surface temperature of a superconducting sample

El modelo de Ginzburg - Landau (TDGLM) es una fuerte herramienta ampliamente utilizada para analizar la magnetización de un estado de vórtice simple en una muestra superconductor mesoscópica en presencia de un campo magnético. El algoritmo implementado es aplicado a una geometria cuadrada rodeada de diferentes tipos de materiales (simulados por la longitude de extrapolación de deGennes ). El interior de la muestra se mantiene a una temperatura constante , mientras su frontera permanece a una temperatura  Esta variación de temperatura en la muestra puede ser generada por una onda laser continua inyectada en todos los puntos internos, excepto en una delgada capa en la superficie del material. Encontramos que, el valor de b en , cual imita la curva de magnetización para un respectivo , presenta una dependencia lineal con la temperature. Por lo tanto, aunque dentro del dominio de validez de la TDGLM el parametro  es considerado independiente de la temperature en la vecindad de la temperatura crítica volumétrica y que  depende de la densidad de estados cercal a la superficie, proponemos una dependencia simple de  usando TDGLM.The Time-dependent Ginzburg–Landau model (TDGLM) is a robust tool widely used to analyze the magnetization of the single-vortex state of a mesoscopic superconducting sample in presence of a magnetic field. The algorithm implemented in this work is applied to a square geometry surrounded by different kinds of materials simulated by deGennes extrapolation length . The inside of the sample remains at constant temperature , while its boundary remains at temperature . This temperature variation in the sample can be generated by a continuous laser wave injected into all the internal points, except for a thin surface layer in the boundary of the material. We found that the b value at , which mimics the magnetization curve for a corresponding , presents a linear dependence with the temperature. Therefore, although within the domain of validity TDGLM the parameter  is to be considered temperature-independent in the vicinity of the bulk critical temperature and that  depends on the density of states near the surface, we propose a simple dependence of using a TDGLM

Experimental estimation of the residual fatigue life of in-service wind turbine bolts

This study presents an experimental methodology aimed at estimating the residual fatigue life of in-service wind turbine bolts. The main objective is to assess the residual life of the bolts to plan their replacement and to avoid unexpected breakages of wind turbine blade connections. To develop the methodology, M16 bolts of quality 10.9 with controlled predamage were used, simulating in-service operating conditions. The fatigue tests were carried out taking care to place the nut at the point on the bolt that produces the highest damage at the same point where the predamage was performed. In addition, the influence of a possible angular positioning error on the residual fatigue life has been investigated. The residual fatigue life is estimated from the difference in fatigue life of new bolt tests and the fatigue life of predamaged bolt tests, simulating service conditions. Special care has been taken to guarantee that the most damaged zone of the bolt in service is also in the position that produces the highest damage during tests. An experimental procedure for determining the fatigue life of a new bolt from tests conducted on a bolt under the same operating conditions was developed. The developed methodology has been applied to M20 bolts belonging to real turbines in service

La iconografía del poder real: el códice miniado de los “Castigos de Sancho IV”. [RESEÑA]

Haro Cortés, Marta La iconografía del poder real: el códice miniado de los “Castigos de Sancho IV”. Historia y Literatura 4. Alcalá de Henares: Universidad de Alcalá, 2014. Col. 177 pp. (ISBN: 978-84-16133-32-1)

Anaerobic digestion of whole-crop winter wheat silage for renewable energy production

With biogas production expanding across Europe in response to renewable energy incentives, a wider variety of crops need to be considered as feedstock. Maize, the most commonly used crop at present, is not ideal in cooler, wetter regions, where higher energy yields per hectare might be achieved with other cereals. Winter wheat is a possible candidate because, under these conditions, it has a good biomass yield, can be ensiled, and can be used as a whole crop material. The results showed that, when harvested at the medium milk stage, the specific methane yield was 0.32 m3 CH4 kg–1 volatile solids added, equal to 73% of the measured calorific value. Using crop yield values for the north of England, a net energy yield of 146–155 GJ ha–1 year–1 could be achieved after taking into account both direct and indirect energy consumption in cultivation, processing through anaerobic digestion, and spreading digestate back to the land. The process showed some limitations, however: the relatively low density of the substrate made it difficult to mix the digester, and there was a buildup of soluble chemical oxygen demand, which represented a loss in methane potential and may also have led to biofoaming. The high nitrogen content of the wheat initially caused problems, but these could be overcome by acclimatization. A combination of these factors is likely to limit the loading that can be applied to the digester when using winter wheat as a substrat

Regulation of c-Jun NH2-terminal Kinase ( Jnk) Gene Expression during T Cell Activation

The c-Jun NH2-terminal kinases (JNKs) are a group of mitogen-activated protein (MAP) kinases that participate in signal transduction events mediating specific cellular functions. Activation of JNK is regulated by phosphorylation in response to cellular stress and inflammatory cytokines. Here, we demonstrate that JNK is regulated by a second, novel mechanism. Induction of Jnk gene expression is required in specific tissues before activation of this signaling pathway. The in vivo and in vitro ligation of the T cell receptor (TCR) leads to induction of JNK gene and protein expression. TCR signals are sufficient to induce JNK expression, whereas JNK phosphorylation also requires CD28-mediated costimulatory signals. Therefore, both expression and activation contribute to the regulation of the JNK pathway to ensure proper control during the course of an immune response