Surface Characteristics and Electrochemical Performance of Activated Carbons from Schinus molle Stones Prepared by Hydrothermal Carbonization and KOH Activation

Schinus molle (SM) stones contain ca. 47 % C and 1 % N and are therefore a potential raw material for the preparation of activated carbons (ACs) with N functionalities. In this study, we investigated the usefulness of SM stones to prepare ACs by hydrothermal carbonization (HTC) followed by KOH activation. For comparison purposes, ACs were also prepared by direct KOH activation of pristine SM stones. The objective was to study the effects of each preparation method on the physico-chemical surface and electrochemical performance of the ACs obtained. Ash content was lower and N content higher in ACs produced by HTC-KOH activation (HSM series) versus direct KOH activation (SM series). All ACs, except the most highly activated sample from the HSM series, had narrow micropores or constricted micropore entrances. The highest surface area and mesopore volume obtained were 1464 m2 g-1 and 0.29 cm3 g-1, respectively. Examination of AC porosity and surface area indicated that SM stones were more reactive to KOH activation after HTC. AC HSM200-2 had the largest capacitance, 235 F g-1 at 0.5 A g-1, and the highest energy density, 7.83 Wh kg-1, at a power density of 400 W kg-1. The electrochemical performance of this sample was comparable to that recently reported for a wide variety of biomass-based ACs

Symmetric Supercapacitor Electrodes from KOH Activation of Pristine, Carbonized, and Hydrothermally Treated Melia azedarach Stones

Waste biomass-derived activated carbons (ACs) are promising materials for supercapacitor electrodes due to their abundance and low cost. In this study, we investigated the potential use of Melia azedarach (MA) stones to prepare ACs for supercapacitors. The ash content was considerably lower in MA stones (0.7% ash) than that found in other lignocellulosic wastes. ACs were prepared by KOH activation of pristine, carbonized, and hydrothermally-treated MA stones. The morphology, composition, surface area, porosity, and surface chemistry of the ACs were determined. Electrochemical measurements were carried out in three- and two-electrode cells, 3EC and 2EC, respectively, using 1 M H2SO4 as the electrolyte. The highest capacitance from galvanostatic charge-discharge (GCD) in 2EC ranged between 232 and 240 F·g−1 at 1 A·g−1. The maximum energy density reached was 27.4 Wh·kg−1 at a power density of 110 W·kg−1. Electrochemical impedance spectroscopy (EIS) revealed an increase in equivalent series resistance (ESR) and charge transfer resistance (RCT) with greater ash content. Electrochemical performance of MA stone-derived ACs was compared with that of other ACs described in the recent literature that were prepared from different biomass wastes and results showed that they are among the best ACs for supercapacitor applications.This work was supported by FEDER and Spanish MINECO (grant number CTQ-2013-44789-R); and Junta de Andalucía (grant numbers P12-RNM-2892, RNM172). HGR gratefully acknowledges COLCIENCIAS (Colombia) for supporting her PhD studies

La anticipación en el deporte y su entrenamiento a través de preíndices

Este trabajo plantea dos partes diferenciadas. Por una parte, se plantea el fenómeno de la anticipación como una habilidad en situaciones deportivas donde el tiempo es un factor determinante de la eficacia. Se tratan en este apartado consideraciones importantes sobre las características de la anticipación en el contexto psicológico de la respuesta de reacción para centrarnos sobre la anticipación espacio-temporal. En segundo lugar, se proponen estrategias de entrenamiento basadas en técnicas de preíndices y en la utilización de sistemas computarizados para optimizar su aprendizaje. Los resultados de trabajos experimentales con deportistas profesionales reflejan la utilidad de estos sistemas automatizados de control de la información en el campo de la psicología del deporte.This article consist of two different parts. At first, we talk about the anticipation like an ability in sport situations where reaction time is a decisive factor to success and the time available is not enough. Important considerations and characteristics of anticipation in the psychological context of the reaction response is shown. In second place, we propose strategies of training based in precuing technique and the use of computerized systems to optimize learning. Experimental results with tennis players witness the utility of these systems of information control in the field of the sport psychology

Adolescents’ Emotions in Spanish Education: Development and Validation of the Social and Emotional Learning Scale

This work was funded by Porticus and the Tomillo Foundation, through the R+D+i Project entitled Evaluation of the Itinerario + Educational Model-Phase I.The aim of this study was to develop and validate a scale for measuring the different areas of competence of the social and emotional learning model in students in compulsory secondary education. For this purpose, following the recommendations and quality standards established by the specialised literature, the Social and Emotional Learning Scale was constructed and administered to a convenience sample of 1385 students in compulsory secondary education. The results reveal adequate reliability of the instrument and fairly satisfactory fit indices for the structural model proposed. In addition, external evidence is provided for the validity of the instrument with the variables life satisfaction and school performance. The Social and Emotional Learning Scale is of satisfactory metric quality and provides a detailed and consolidated picture of adolescents’ level of self-awareness, social awareness, self-control, interpersonal skills and responsible decision making, which provides students with an instrument that can help to understand their interpersonal and intrapersonal skills and to establish mechanisms for their improvement.PorticusTomillo Foundation, through the R+D+i Project entitled Evaluation of the Itinerario + Educational Model-Phase

Multivariate optimization of the KharascheSosnovsky allylic oxidation of olefins

The multivariate optimization method known as simplex is applied to the KharascheSosnovsky allylic oxidation of double bonds. By applying this method, the amounts of three variables (copper source, oxidant, and additive) are optimized at the same time. Under the conditions thus obtained the reaction takes place in a considerable shorter time, being the alkene the limiting reagent. These conditions are applied to some monoterpenes and sesquiterpenes leading regioselectively to the corresponding benzoate esters, opening a route to the employment of this reaction in the synthesis of more complex molecules

Harmonic model of electronically controlled loads

The use of electronically controlled loads is the way used to improve the efficiency as well as the power factor of normal elec- tric loads, obtaining thus energy efficient loads. This electronic con- trol changes the load’s global behavior resulting in a strongly non- linear one, at this regards, the available models used to represent loads are not accurate enough, especially in the context of an iterative frequency domain harmonic penetration program/algorithm. In this article, we propose an extension of the crossed-frequency admittance matrix, in order to get a better representation of these electronic loads. The extension is done by adding another dimension to the matrix, the harmonic phase. The model is obtained using a programmable power source connected to a PC, and by means of an acquisition board, we measure voltage and intensity. Due to the large number of tests needed we have developed a software tool that auto- mates the process giving as result the load model. Therefore, the proposed model linearizes loads according to three variables: Amplitude, Frequency and Phase of the harmonic with regard to the fundamental

Approach to multivariable predictive control applications in residential HVAC direct load control

The purpose of this paper is to describe a new constrained multivariable predictive control strategy applied in Residential HVAC Direct Load Control. In this way, starting from a target load profile prefixed by the utility in order to achieve several objectives - economic, technical- and taking into account customer constraints - minimum “fort levels, HVAC limits- this control algorithm provides, in a multiobjective hework, the most suitable HVAC load control strategy to minimize the discrepancies between the controlled load curve and the predefined target load curve. The control system has a close-loop behavior with a proper and consistent treatment of modeling errors and other disturbances. It is allowed a dynamic modification of the target load me according to the real-time system behavior. In order to demonstrate its qualities widely, this control system has been applied to modify a real load curve profile under different operating conditions

Supply Chain Risk of Obsolescence at Simultaneous Robust Perturbations

The earlier planning methods of supply chains (SC) in the skeleton of the extended material requirements planning (EMRP), where the time horizon of the reverse Laplace is infinite, were not convenient to estimate the impact of the technical obsolescence of the product or technology involved, which has economic, environmental, and social consequences. Therefore, the perturbations of timing are presented until the possible obsolescence, with parallel execution of the network simulation model (NSM) to evaluate the impact of the finite lifespan on the value of the chain. The EMRP, as well as the NSM, are based on the skeleton of the material requirements planning model, where delays and their perturbations are presented transparently. Contrary to the previous studies of the net present value (NPV) in the EMRP skeleton, where the infinite horizon is assumed, the impact of shortening the horizon of activities is shown here, in order to also evaluate the risk of financing investments in the SC with a shorter lifespan of products or technology. Owing to the simultaneous appearances of the stochastic variables, the parallel execution and exchanging of data, using NSM is advised. The procedures for estimation of correction factors of the NPV and their values are given.This research was partly funded by the Slovenian Research Agency, grant P5-0364 and J6-9396, and partly by the University of Padua