Synthesis and Characterization of functional ceramic materials at the nano- and microscale with enhanced properties

Semiconductor nanoparticles (NPs) and nanowires (NWs) of doped ZnO system have been synthesised at low temperature (190 °C) by a novel Polyol-Mediated Thermolysis (PMT) process and Vapour-Solid (VS) reaction. Ce/Ru doped ZnO NPs with different molar content (1-3--5-10%) have been synthesised by both experimental processes. The crystallite size, morphology, specific surface area and band gap have been evaluated. Also, the structural and functional characteristics were carried out by X-ray diffraction technique (XRD), high resolution transmission electron microscopy (HRTEM), Brunauer, Emmett and Teller (BET) method, UV-Vis diffuse reflectance spectra (DRS), UV-Vis spectroscopy and photoluminescence measurements (PL). Also, the photocatalytic activities of ZnO nanoparticles were evaluated by removal rate of methyleneblue (MB) under UV irradiation (365 nm) at RT. XRD patterns revealed a hexagonal ZnO wurtzite-type crystalline structure with a preferred orientation of(101) plane. Any secondary phases have been identified such as Ce02, Ce203, ee, Ru02, Ru304, Ru. HRTEM showed NPs in shape from spherical/ellipsoidal to hexagonal, that does not change significantly with the increasing of precursor solution concentration and kind of dopant element in the samples obtained from PMTprocess. The size of NPs was observed in the range from 16 to 23 run. Using the Kubelka-Munk treatment on the diffuse reflectance spectra, the direct band energy has been estimated at <3.0 eV in the Ru-doped samples. The PL spectra mainly consist of four emission bands: (i) a strong UV emission band, (ii) a weak blue band, (iii) a blue-green band and (iv) a green-yellow band, respectively. The reported results showed the photocatalytic efficiency of doped ZnO nanoparticles was always enhanced

Towards Applying River Formation Dynamics in Continuous Optimization Problems

River Formation Dynamics (RFD) is a metaheuristic that has been successfully used by different research groups to deal with a wide variety of discrete combinatorial optimization problems. However, no attempt has been done to adapt it to continuous optimization domains. In this paper we propose a first approach to obtain such objective, and we evaluate its usefulness by comparing RFD results against those obtained by other more mature metaheuristics for continuous domains. In particular, we compare with the results obtained by Particle Swarm Optimization, Artificial Bee Colony, Firefly Algorithm, and Social Spider Optimization

Synthesis of Ce/Ru Doped ZnO photocatalysts to the degradation of emerging pollutants in wastewater

Semiconductor nanoparticles (NPs) and nanowires (NWs) of doped ZnO system with different dopant content have been synthesized by Polyol-Mediated Thermolysis (PMT) process and Vapour-Solid (VS) reaction. The average crystallite size, morphology, specific surface area, and direct band gap have been evaluated. The structural and functional characteristics have been studied by X-Ray Diffraction techniques (XRD), Field Emission Scanning Electron Microscope (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), Brunauer, Emmett and Teller (BET) method, UV-Vis Diffuse Reflectance Spectra (DRS), UV-Vis Spectroscopy, and Photoluminescence measurements (PL). Also, the photocatalytic activities of pure and doped ZnONPs were evaluated by removal rate of Methylene Blue (MB) under UV irradiation (365 nm) at room temperature. XRD patterns revealed the common hexagonal ZnO Wurtzite-type structures with a preferred orientation of (101) plane. Secondary phases as CeO2, Ce2O3, Ce, RuO2, Ru3O4, Ruhave been identified. For both dopant, Ceand Ru, and for all the concentrations in the precursor solution, FESEM and HRTEM showed NPswith morphologies ranging from spherical/ellipsoidal to hexagonal. The size of NPs was observed to decrease (from ~30 to ~16 nm) with increasing doping concentration due to the interaction between the Ce-O-Zn or Ru-O-Zn ions. EDS results confirmed the incorporation of Ce or Ru ions into ZnO lattice.Using the Kubelka-Munk treatment on the diffuse reflectance spectra, the direct band gap energy has been estimated to be slightly lower than 3.0 eV in both, the Ce and Ru-doped samples. Compared with pure ZnO NPs, the PL spectra of the doped NPs showed red-shifted UV emission and an enhanced blue emission with the typical broad green-yellow emission. The results showed that photocatalytic efficiency of doped ZnO NPs was always enhanced

Thermoluminescence from europium doped gadolinium oxide aerosols

Poster presented at the International Roundtable on Advanced Wide Band Gap Materials for Radiation Detectors - MATRAD 2007, June 17 till June 20, 2007 in Sinaia, Romani

A experiência da metodologia camponês a camponês em territórios de identidade rural no Nordeste do Brasil.

A pesquisa teve por objetivo a promoção da transição agroeocológica em territórios de identidade rural por meio do ajuste da metodologia ?campesino a campesino? visando à promoção do desenvolvimento sustentável e solidário nas condições do Nordeste do Brasil. Foram identificadas famílias agricultoras camponesas com perfil para inserção em redes de transição agroecológica, potenciais promotores de intercâmbios entre elas para a troca de experiências e saberes. O trabalho foi realizado no Território de identidade rural Sul Sergipano localizado nos tabuleiros costeiros do estado de Sergipe. A realização das ações resultou de uma parceria efetiva entre Colegiado Territorial, Empresa Brasileira de Pesquisa Agropecuária (Embrapa), Instituto Nacional de Colonização e Reforma Agrária (INCRA-SE), Movimento dos Trabalhadores Sem Terra (MST), Universidade Federal de Sergipe (UFS), Universidade Federal de Viçosa (UFV) e Centro de Formação e Assistência Comunitária (CFAC). Para a operacionalização do trabalho e ajuste da metodologia foram potencializadas as redes sociais de agroecologia existentes na região. Os resultados referem-se à identificação das principais experiências de transição agroecológica da região, a consolidação das redes existentes e a criação de formas inovadoras de intercâmbio de experiências potencializadas pela metodologia ajustada, então denominada ?camponês a camponês?. Os aprendizados referem-se à forma de construção coletiva necessária para a introdução de conhecimento agroecológico e, principalmente, de conceitos de maior complexidade, como agrofloresta sucessional e, a perspectiva de construção de uma nova abordagem para a extensão rural em agricultura familiar e camponesa em territórios de identidade rural

Development of a Multicriteria Scheme for the Identification of Strategic Areas for SUDS Implementation:A Case Study from Gijón, Spain

Spain has been pinpointed as one of the European countries at major risk of extreme urban events. Thus, Spanish cities pursue new urban plans to increase their resilience. In this scenario, experiences in the implementation of Sustainable Urban Drainage Systems (SUDS) have increased substantially. Nevertheless, few cities have developed a global urban strategy for SUDS, lacking, in many cases, a method to identify strategic areas to maximize their synergetic benefits. Furthermore, there is still a need for a holistic Multicriteria Decision Analysis (MCDA) framework that considers the four pillars of SUDS design. The city of Gij&oacute;n, NW Spain, has been selected as a case study due to its environmental and climatic stresses. This research presents the methodology developed for this city, which aims to analyze the need for SUDS implementation throughout the identification of strategic areas. With this aim, a combination of Geographic Information System (GIS) software and the MCDA Analytical Hierarchical Process (AHP) were proposed. The results show the potential for SUDS&rsquo; implementation, according to nine criteria related to the SUDS&rsquo; design pillars. We found that the areas where the implementation of SUDS would bring the greatest functional, environmental and social benefits are mainly located in consolidated urban areas

Propuesta de modelo para estimar el estado de carga de baterías de LiFePO4 para un vehículo eléctrico

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMEN: El dimensionamiento de un sistema de almacenamiento juega un papel indispensable a la hora de proporcionar una fuente de energía constante. Sin embargo, estos sistemas luchan con la inestabilidad de los parámetros resistivos entre celda y celda, que finalmente logran variar la previsión de diseño. Este trabajo contribuye con una metodología de modelado y simulación para un sistema eléctrico de un vehículo eléctrico utilizando la plataforma Matlab-Simulink. El objetivo es estimar el estado de carga y, por tanto, la autonomía del sistema de tracción eléctrica. Se estudian las condiciones tanto internas como externas en las que funciona un EV y se construye un prototipo de EV para validar los resultados de las simulaciones. El modelo computacional propone el uso de polinomios característicos de las curvas de trabajo de un motor eléctrico y de los componentes RC del circuito equivalente de una batería. Se modelan las ecuaciones matemáticas que representan las fuerzas a las que está sometido el tren de tracción y se obtiene la corriente que se extrae del sistema de almacenamiento ().ABSTRACT: Sizing a storage system plays an indispensable role in providing a constant energy source. However, these systems struggle with the instability of resistive parameters between cell and cell, which finally manages to vary the design forecast. This work contributes with a modeling and simulation methodology for an EV power system using the Matlab-Simulink platform. The aim is to estimate the state of charge and, therefore, the autonomy of the electrical traction system. Both internal and external conditions in which an EV works are studied and an EV prototype is built to validate the results of the simulations. The computational model proposes the use of characteristic polynomials of the work curves of an electric motor and of the RC components of the equivalent circuit of battery. The mathematical equations that represent the forces to which the traction train is subjected are modeled and the current that is extracted from the storage system ().info:eu-repo/semantics/publishedVersio

Descriptive Analysis of the Performance of a Vegetated Swale through Long-Term Hydrological Monitoring: A Case Study from Coventry, UK

Vegetated swales are a popular sustainable drainage system (SuDS) used in a wide range of environments from urban areas and transport infrastructure, to rural environments, sub-urban and natural catchments. Despite the fact that vegetated swales, also known as grassed swales, have received scientific attention over recent years, especially from a hydrological perspective, there is a need for further research in the field, with long-term monitoring. In addition, vegetated swales introduce further difficulties, such as the biological growth occurring in their surface layer, as well as the biological evolution taking place in them. New developments, such as the implementation of thermal devices within the cross-section of green SuDS for energy saving purposes, require a better understanding of the long-term performance of the surface temperature of swales. This research aims to contribute to a better understanding of these knowledge gaps through a descriptive analysis of a vegetated swale in Ryton, Coventry, UK, under a Cfb K&ouml;ppen climatic classification and a mixed rural and peri-urban scenario. Precipitation and temperature patterns associated with seasonality effects were identified. Furthermore, a level of biological evolution was described due to the lack of periodical and planned maintenance activities, reporting the presence of both plant species and pollinators. Only one event of flooding was identified during the three hydrological years monitored in this research study, showing a robust performance