The objective of this work was to determine the adsorption capacity of activated carbons from almond shells in a fixed bed at low concentration of two solvents, n-hexane and toluene, as well as to study the desorption process in order to n-hexane and toluene recovery.Activated carbons with different physicochemical characteristics were obtained by chemical activation of almond shells varying activation temperature, impregnation ratio and activation time, following an experimental design. Although a number of variables affect adsorption capacity under dynamic mode, such as adsorption temperature, initial concentration and spatial velocity, under the same operating conditions activated carbons exhibit quite different adsorption capacities. High adsorption capacities at low n-hexane and toluene concentration have been obtained: 253 mg toluene/g and 122 mg n-hexane/g. However, the reduction of adsorption capacity comparing that obtained in static mode and dynamic mode does not follow a trend. This reduction it is not proportional either among the activated carbons for a single solvent or for one activated carbon with both solvents.The n-hexane and toluene adsorption capacities obtained at low concentration do not correlate directly with textural characteristics and surface chemistry is involved in the adsorption process. The deviation of linearity of the Dubinin-Radushkevich model applied to solvent isotherms gives an appropriate idea of heterogeneity of the activated carbon, giving a range of deviation that maximizes n-hexane and toluene adsorption capacity.

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Volatile organic compounds emission has important effects over the environment and human beings health. When these substances cannot be substituted, adsorption systems are still a very common solution to VOCs emission, but for their design, previous laboratory work is necessary: adsorption isotherms and breakthrough curves must be obtained. The first ones establish the maximal amount of adsorbate retained over the solid adsorbent for a certain pressure of the adsorbate, and the second ones define the adsorption process kinetics. Once this information is studied, a theoretical breakthrough time model can be built up, and then the scale up of the adsorption system can be developed. This process is rather complex for multicomponent gas mixtures, where a competition between adsorbates happens. Thus, the aim of this paper is to establish a guide for authors willing to develop breakthrough time prediction models for multicomponent systems through a critical review of different adsorption and kinetic models.

La búsqueda del máximo rendimiento en el deporte de élite se basa en una preparación física, técnica, táctica y mental. El tenis, caracterizado por el juego bajo presión y la ausencia de comunicación con el equipo técnico, provoca que el diálogo con uno mismo sea muy frecuente. El auto-habla se ha relacionado con una mejora del rendimiento, atendiendo al deporte, sexo y nivel. No obstante, no se encuentran estudios dirigidos a analizar el tipo de auto-habla que utilizan mujeres tenistas profesionales. Es por ello que los objetivos del presente estudio fueron observar cuáles son las verbalizaciones que más se usan en el tenis femenino y valorar qué tipo de auto-habla es el más utilizado. Un total de 11 mujeres tenistas profesionales (24,65±5,62 años), con una clasificación internacional entre el puesto 16º y 802º, contestaron una encuesta auto-administrada y anónima que se les proporcionó de forma virtual. Se examinaron las expresiones según la clasificación reciente de los tipos de auto-habla, analizándose con Chi-cuadrado su variación. Se destaca que todas las jugadoras conocían la técnica, exceptuando una. El tipo de auto-habla más utilizado fue el orgánico dirigido a un objetivo (AODO), sin verse apenas modificado en función de la clasificación de las jugadoras y la expresión más utilizada fue “Vamos”. La madurez de las tenistas profesionales les permite seleccionar el AODO en momentos delicados del partido y mantener así una mayor estabilidad emocional. Conocer qué palabras utilizan tenistas profesionales puede ayudar a los formadores a gestionar y mejorar el tipo de auto-habla que más conviene en jugadores en formación. Abstract. The search for maximum performance in elite sport is based on physical, technical, tactical and mental training. Tennis, characterized by the game under pressure and the lack of communication with the technical staff, causes a frequent dialogue with oneself. Self-talk has been related to improved performance, depending on the sport, sex and level. However, there are no studies aimed at analyzing the type of self-talk used by women professional tennis players. The goals of this study were to observe which verbalizations are most used in women's tennis and to assess what type of self-talk is the most used. A total of 11 female professional tennis players (24.65±5.62 years old), with an international ranking between 16th and 802nd, answered a self-administered and anonymous survey that was provided to them virtually. The expressions were examined according to the recent classification of the types of self-talk, analyzing their variation with Chi-square. It stands out that all the players knew the technique, except one. The most used type of self-talk was organic goal-directed (AODO), with little change depending on the players' classification and the most used expression was "Let's go". The maturity of professional tennis players allows them to select the AODO in decisive moments of the match and thus maintain greater emotional stability. Knowing what words professional tennis players use can help trainers to manage and to improve which is the best type of self-talk for players’ training.