Sintering to Transparency of Polycrystalline Ceramic Materials

Open Access: InTech Open.Peer Reviewe

Sustainable earthworks: Optimization with the ICOM method

Tmrees, EURACA, 13 to 16 April 2020, Athens, Greece[EN] In the construction of highways and roads, one of the main activities is earthworks. This activity has an economic and environmental impact that cannot be overlooked. The classic method, based on the use of mass diagram models and optimization, does not take into account the type and quality of the material found on site, making it difficult to optimize the actual flow of each material. The ICOM method (Intelligent Method of Optimized Mass Compensation) allows the optimization of classic works such as excavations and fillings resulting in the optimization of operating costs. This versatile method contemplates different options for each project and allows choosing the most appropriate one taking into account, among other factors, the distance travelled by each type of material, which translates into the amount of CO2 emitted and waste generated. This is why the use of the iCom method will enable us to make the work sustainable, while reducing environmental pollution and the amount of waste. This article compares the results obtained by applying the ICOM method with those that can be obtained with the classic method for twenty-four work projects in Spain and Portugal. The results analysed show that the ICOM method achieves a significant reduction in financial costs between 5% and 14.1% and a shortening of the time needed to carry out the work. The method also obtains a reduction in CO2 emissions (between 5.1% and 14%), while generating a smaller volume of waste materials, which implies a reduction in environmental impact. Furthermore, this method provides the reports, plans and diagrams necessary for the complete definition of the earthworks to be carried outS

A strong magneto-optical activity in rare-earth La3+ substituted M-type strontium ferrites

The Creative Commons Attribution 3.0 Unported License to their work.M-type strontium ferrites with substitution of Sr2+ by rare-earth La3+ were prepared by conventional ceramic technology. The structure, magnetic properties, and magneto-optical Kerr activity of Sr1−xLaxFe12O19 (x = 0, 0.05, 0.10, 0.15, 0.20) were investigated by x-ray diffraction (XRD), vibrating sample magnetometer (VSM), and magneto-optical ellipsometry, respectively. X-ray diffraction showed that the samples sintered at 1290 °C for 3 h were single M-type hexagonal ferrites. The magnetic properties were remarkably changed due to the valence change of Fe ions induced by the substitution of La ions. Most significantly, an important magneto-optical activity was induced in the La3+ substituted M-type strontium ferrites around 3 eV.The authors acknowledge the financial support from the National Natural Science Foundation of China under Grant Nos. 50672001 and 51072002, the 211 Project of Anhui University and from the Spanish Ministry of Education and Science under project MAT2009-14534-C03-03. L. Fernandez- Garcia acknowledges the JAE program for a PhD grant.Peer reviewe

Analysis of the Chemistry activities in 1st level of Spanish Bachelor Physics and Chemistry textbooks from a «Chemistry in context» approach

In the last few years there are two worrying phenomenon happening in the science teaching environment, on one hand there are fewer students who choose science subjects at the time they’re optional and on the other hand the decreasing number of university students enrolled in science careers, if we add those two facts the results of the latest pisa tests, which show that students who choose these materials do not get satisfactory results, we have a hopeless outlook. One way of analysing the situation is exploring what happens in the classroom and in this context we find that the textbook is a resource used extensively in the teaching of Chemistry; one essential element for learning are planned activities in the classroom, so it seems essential to make a full review of them. The objectives in this study are: Analysing and classifying the activities contextualized of chemistry textbooks currently used in eleventh grade and comparing books from different educational laws based on their contextualized activities. For the review and classification of activities it uses a methodology of analysis for qualitative content. The results demonstrate the anecdotic presence of this kind of activities in textbooks; 8308 activities were reviewed of which only 6,46% corresponded to contextualized activities. In addition when comparing the different books, whether they are currently used or the ones from previous educational laws, we see that there is not a turnaround in what refers to the contextualized activities, as a significant variation is not observed in the percentages and therefore do not adapt well to curriculum changes./n En los últimos años se están produciendo dos fenómenos preocupantes en la enseñanza de las ciencias, por un lado, cada vez son menos los alumnos que escogen las materias de ciencias cuando éstas son optativas y, por otro, está disminuyendo el número de estudiantes universitarios matriculados en carreras de ciencias; si a estos hechos sumamos los resultados obtenidos en las últimas pruebas Pisa, que ponen de manifiesto que los estudiantes que escogen estas materias no obtienen resultados satisfactorios, nos encontramos ante un panorama, cuando menos, poco esperanzador. Una vía de análisis de la situación es explorar lo que ocurre en el aula y en este contexto encontramos que el libro de texto es un recurso intensamente utilizado en la enseñanza de la Química; un elemento clave para el aprendizaje son las actividades planteadas en el aula, por eso parece esencial realizar una revisión exhaustiva de las mismas. Los objetivos planteados en el presente trabajo son: Analizar y clasificar las actividades contextualizadas de química de los libros de texto que se usan actualmente en primero de Bachillerato y comparar las actividades de libros de distintas leyes educativas en base a sus actividades contextualizadas. Se utiliza para la revisión y clasificación de las actividades una metodología de análisis cualitativo del contenido. Los resultados ponen de manifiesto la anecdótica presencia de esta clase de actividades en los textos escolares; en total se revisaron 8308 actividades de las cuales solamente un 6,46% corresponde a actividades contextualizadas. Además, al comparar los distintos libros, tanto los que se usan actualmente como los de leyes anteriores, vemos que no existe un cambio de tendencia en los mismos en lo referente a las actividades contextualizadas, ya que no se observa una variación significativa en los porcentajes y, por lo tanto, no se adaptan bien a los cambios del currículo

Treatment of Soil Contaminated by Mining Activities to Prevent Contamination by Encapsulation in Ceramic Construction Materials

[EN] Mining is an essential activity for obtaining materials necessary for the well-being and development of society. However, this activity produces important environmental impacts that must be controlled. More specifically, there are different soils near new or abandoned mining productions that have been contaminated with potentially toxic elements, and currently represent an important environmental problem. In this research, a contaminated soil from the mining district of Linares was studied for its use as a raw material for the conforming of ceramic materials, bricks, dedicated to construction. Firstly, the contaminated soil was chemically and physically characterized in order to evaluate its suitability. Subsequently, different families of samples were conformed with different percentages of clay and contaminated soil. Finally, the conformed ceramics were physically and mechanically characterized to examine the variation produced in the ceramic material by the incorporation of the contaminated soil. In addition, in this research, leachate tests were performed according to the TCLP method determining whether encapsulation of potentially toxic elements in the soil occurs. The results showed that all families of ceramic materials have acceptable physical properties, with a soil percentage of less than 80% being acceptable to obtain adequate mechanical properties and a maximum of 70% of contaminated soil to obtain acceptable leachate according to EPA regulations. Therefore, the maximum percentage of contaminated soil that can be incorporated into the ceramic material is 70% in order to comply with all standards. Consequently, this research not only avoids the contamination that contaminated soil can produce, but also valorizes this element as a raw material for new materials, avoiding the extraction of clay and reducing the environmental impact.S

A Health Sector Online Toolkit for Implementing Learning into Practice from Violence Against Women Trainings (TILPVAWT)

Violence against women (VAW) is a major public health and human rights concern. Intimate partner violence and sexual violence are among the most pervasive forms of violence against women. Training health professionals in VAW is essential to raise awareness and improve the care for victims with a comprehensive approach. One of the objectives of this project was the development of a set of 28 tools to facilitate VAW training of health professionals, using certain common content, and the transfer of this knowledge into their clinical practice. This toolkit has been presented on the website http://www.toolner.com/en/. This website has been designed in an easy to use and friendly way, and is oriented to trainers, organisations and individuals interested in improving their teaching skills in VAW, but with the potential to be adapted and used independently by different organisations. The toolkit is divided into five phases of training: preparation, development, implementation, post-training, and assessment; each containing different tools and examples. Training in VAW is the first step to change attitudes but it is necessary to motivate professionals, adapt content, methodology and assess the impact of the training. This website is a tool by which to achieve this

Microstructure and mechanical properties of 5.8 GHz microwave-sintered ZrO2/Al2O3 ceramics

[EN] Aim of the present study is to sinter zirconia nanocomposite powders doped with ceria and toughened with alumina (10Ce-TZP/Al2O3) by non-conventional means, i.e. microwave sintering technology. The sintering effects of various microwave applicators and frequency generators were evaluated using an optimised experimental set-up. The microwave-sintered samples were compared with the composites sintered by the conventional method. The mechanical properties of the ceramic composites were evaluated by their hardness, fracture toughness and Young's modulus. Likewise, their density and microstructure were analysed.The authors thank the Generalitat Valenciana for the financial support provided to the PROMETEU/2016/040 project. A. Borrell is grateful to the Spanish Ministry of Economy and Competitiveness for her RyC contract (RYC-2016-20915).Gil-Flores, L.; Salvador Moya, MD.; Penaranda-Foix, FL.; Fernández, A.; Suárez-Menéndez, M.; Rosa, R.; Veronesi, P.... (2019). Microstructure and mechanical properties of 5.8 GHz microwave-sintered ZrO2/Al2O3 ceramics. Ceramics International. 45(14):18059-18064. https://doi.org/10.1016/j.ceramint.2019.06.026S1805918064451

Smoking is associated with age at disease onset in Parkinson's disease

[Background] Previous studies linked disease-progression variables such as age at onset or survival to both genetic, and non-genetic factors in Parkinson's disease (PD) patients.[Objective] The aim of this study was to assess how genetic and non genetic factors act as modifiers of age at onset and survival and in a cohort of 753 PD patients, and to determine how these variables interact to define the overall risk.[Methods] We analyzed the effect of gender, tobacco, alcohol, type of PD (genetic, gPD or idiopathic, iPD) and three genetic variants rs5848- GRN, rs1042522- TP53 and APOE. We studied two cohorts (PPMI and IPDGC) to replicate positive results.[Results] Regarding age at onset, male smokers PD had a significantly lower mean age compared to non-smoker (p = 0.001). APOE-Ɛ4 carriers had a younger onset-age compared to non-carriers (p = 0.03) in the Spanish cohort, but these results were not replicated in the other cohorts. Concerning survival, PD patients with an early onset (below 50 years) had an increased survival rate (p < 0.001).[Conclusions] Our study showed how several genetic and non-genetic risk factors influenced the age at onset and survival in PD.Irene Rosas was supported by a grant from Fundación Jose Luis Castaño-SEQC. Sergio Pérez-Oliveira is supported by Fundación Parkinson Asturias-Obra Social Cajastur. This study was supported by grant PI 15/00878 (Fondos Feder) to VA.Peer reviewe

Soluble co-signaling molecules predict long-term graft outcome in kidney-transplanted patients

Co-signaling molecules are responsible for full T-cell activation after solid organ transplantation. Their increased expression can lead to the release of a soluble form that can modulate the immune response post-transplantation. We analyzed the presence of co-signaling molecules (sCD30, sCD40, sCD137, sCTLA-4, sCD80, sCD28, sCD40L, sPD-1, and sPD-L1) in serum from kidney-transplanted patients (n = 59) obtained at different times (before transplantation, and 15 days, 3 months and 1 year post-transplantation) and their contribution to graft outcome was evaluated using principal component analysis. Before transplantation, high levels of soluble co-signaling molecules (mainly sCD30, sCD137 and sCD40) were detected in all patients. These molecules were modulated soon after receiving an allograft but never attained similar levels to those of healthy controls. A signature based on the determination of six soluble co-stimulatory (sCD30, sCD40, sCD137 and sCD40L) and co-inhibitory (sPD-1 and sPD-L1) molecules at 3 months post-transplantation allowed a group of patients to be identified (27.12%) with a worse long-term graft outcome. Patients with high levels of soluble molecules showed a progressive and gradual deterioration of kidney function (increased creatinine and proteinuria levels and decreased estimated glomerular filtration rate) over time and a higher risk of graft loss at 6 years post-transplantation than patients with low levels of these molecules (62.55% versus 5.14%, p<0.001). Thus, our data show an aberrant expression of soluble co-signaling molecules in kidney-transplanted patients whose quantification at 3 months post-transplantation might be a useful biomarker of immune status and help to predict long-term graft evolution