Determination of Solidification of Rigidity Point Temperature Using a New Method

This work aims to calculate the rigidity point temperature of aluminum alloys by three new methods and compare them with currently employed methods. The influence of major and minor alloying elements over the rigidity point temperature is also discussed. Until now it has been difficult to determine the exact temperature of the rigidity point, since small variations in the data obtained give variable results, making it difficult to automate the process with high accuracy. In this work we suggested three new mathematic methods based on the calculation of higher order derivatives of (dT/dt) with respect to time or temperature compared to those currently employed. A design of experiments based on the Taguchi method was employed to compare the effect of the major and minor alloying elements for the AlSi10Mg alloy, and to evaluate the accuracy of each developed method. Therefore, these systems will allow better automation of rigidity point temperature (RPT) determination, which is one of the most important solidification parameters for solidification simulators. The importance of the correct determination of this parameter lies in its relation to quality problems related to solidification, such as hot tearing. If the RPT presents very low-temperature values, the aluminum casting will be more sensitive to hot tearing, promoting the presence of cracks during the solidification process. This is why it is so important to correctly determine the temperature of the RPT. An adequate design of chemical composition by applying the methodology and the novel methods proposed in this work, and also the optimization of process parameters of the whole casting process with the help of the integrated computational modeling, will certainly help to decrease any internal defective by predicting one of the most important defects present in the aluminum industry.This research was partially funded by the Basque Government through the Etorgai Programme 2016, under the Filing Identification Number ZE-2016/00018 and the Elkartek Programme 2020, KK-2020-00047 for research, technological development and demonstration

A first approach to an axiomatic model of multi-measures

We establish an axiomatic model of multi-measures, capturing some classes of measures studied in the fuzzy sets literature, where they are applied to only one or two arguments

The family as a deciding factor in the choice of teaching

Aproximación a la situación de las mujeres en la legislación educativa del siglo XIX. La influencia de la familia en la elección del magisterio como actividad laboral. El Archivo de la Universidad de Cádiz como base de la documentación utilizada.Approach to the situation of women in the educational legislation of the 19 th century. The influence of the family in the choice of teaching as a work activity. The General Archive of the UCA as the basis of the documentation used

Plaza de Las Glorias Catalanas: la periferia desde el tiovivo

Este trabajo presenta una visión sobre la Plaza de las Glorias Catalanas dividida en dos partes. En la primera se muestran intencionadamente algunos aspectos que han condicionado este lugar y le han dado el carácter de periferia que se subraya en la presente tesina. En la segunda parte se analiza el desarrollo del lugar en los últimos veinte años, mostrándolo tal como es hoy

Effect of aryl phosphates on toxicity of combustion gases of flame‐retardant polycarbonate/acrylonitrile butadiene styrene blends according to EN 45545 railway standard

In this study, the toxicity of combustion gases of polycarbonate/acrylonitrile butadiene styrene (ABS) blends that include aryl phosphates as flame-retardants (FRs) was analyzed according to the European railway standard EN 45545-2 (NBS chamber + FTIR). FRs have a significant influence on the evolution of the toxicity of gases generated during the combustion process. In the experiment, the asphyxiant hydrogen cyanide (HCN) was detected at the beginning of combustion (4 min of testing) as a product of ABS degradation. CO was generated throughout the test (8 min) because of the incomplete combustion of both the ABS and PC fractions. The presence of aryl phosphates promoted the inhibition of the flame. The reaction of PO radicals in the gas phase resulted in OH scavenging and a higher release of HCN and CO. The results suggest that aryl phosphates act in the first 4 min and do not have an effect later. FRs with lower thermal stability exhibited lower heat release and flame propagation but generated more toxic gases. This effect is attributed to the higher activity of the flame-retardant in the gas phase. Further, additional fire performance parameters, including thermal stability (thermogravimetric analysis), flammability (UL94), and heat and smoke generation (cone calorimeter), were studied. It was found that aryl phosphates reduced the fire hazard, prevented the spread of the flame, reduced heat generation, increased the time to ignition, and, at the same time, promoted the emission of toxic gases that differ in function of the selected flame-retardantThe authors are grateful to the European Commission for its support in the Close WEEE Project GA 641747 and POLYCE project GA 73030

Reforma i adequació de l’edifici Via Laietana 2 de Barcelona

Primer premiAward-winningPostprint (published version

EL ACTUAR DE LAS ORGANIZACIONES DE LA SOCIEDAD CIVIL DE CHALCO Y SU RELACIÓN CON LA DEMOCRACIA

Trabajo que aporta conocimiento novedoso respecto a las organizaciones sociales en ámbitos municipales.El trabajo busca explicar que factores influyen en el comportamiento de los líderes de las Organizaciones de la Sociedad Civil en el municipio de Chalco, Estado de México. A través de entrevistas y observación participante, se estableció que las organizaciones de la sociedad civil en Chalco logran vincularse con la población por medio de programas sociales y de gobierno, canalizando recursos varios, como medicinas, despensas, de higiene, control natal y ecológicos; pero no fomentan ni tienen un actuar democrático, ni al exterior ni al interior. Además se describe la función y formas de organización que permite entender su financiamiento y objetivos sociales y políticos