A comparative study of acid and alkaline aluminum extraction valorization procedure for aluminum saline slags

A management process for saline slags, one of the wastes from Secondary Aluminum Production, is proposed. The process begins with a grinding step, followed by washing with water, which removed the fluxing salts but provoking the hydrolysis of AlN, yielding Al(OH)3 and ammonia. Sieving of the solid generated an intermediate and a fine fraction. The first one was rich in metallic aluminum, and can also be returned to the Secondary Aluminum Production. The fine fraction was submitted to a extraction process in acid (HCl or HNO3) or alkaline (NaOH, KOH or CsOH) conditions, under reflux at 90 ºC, obtaining an Al(III) solution that can be used in the synthesis of aluminum-based solids. HCl (1-8 mol/L) and NaOH (1-4 mol/L) were used as reference solutions, HNO3, NaOH and KOH were used under specific conditions; the slag fraction:extraction solution solid:liquid ratio was also varied. The optimum extraction conditions were: extraction time 2 h, solid:liquid ratio 3:10, concentration 3 mol/L for the NaOH medium and 4 mol/L for the HCl medium. More than 30% of the aluminum present in the fraction smaller than 0.4 mm was recovered (the remaining aluminum was present as insoluble phases, corundum and spinel). Acid or basic media can be selected depending on the final use of Al(III) solutions, the basic medium leading to an Al(III) solution with a lower amount of impurities. The hazardousness of the solid obtained after the extraction process was greatly decreased, making possible the use of this solid residue in sectors such as construction.This work was supported by 'Memoria de D. Samuel Solórzano Barruso' Foundation (FS/11-2020). AJ thanks Universidad de Salamanca and Banco Santander for a predoctoral contract. AG is grateful for financial support from the Spanish Ministry of Science and Innovation (MCIN/AEI/10.13039/501100011033) through project PID2020-112656RB-C21. AG also thanks Santander Bank for funding via the Research Intensification Program

Rank-(n – 1) convexity and quasiconvexity for divergence free fields

The CAST experiment at CERN (European Organization of Nuclear Research) searches for axions from the sun. The axion is a pseudoscalar particle that was motivated by theory thirty years ago, with the intention to solve the strong CP problem. Together with the neutralino, the axion is one of the most promising dark matter candidates. The CAST experiment has been taking data during the last two years, setting an upper limit on the coupling of axions to photons more restrictive than from any other solar axion search in the mass range below 0.1 eV. In 2005 CAST will enter a new experimental phase extending the sensitivity of the experiment to higher axion masses. The CAST experiment strongly profits from technology developed for high energy physics and for X-ray astronomy: A superconducting prototype LHC magnet is used to convert potential axions to detectable X-rays in the 1-10 keV range via the inverse Primakoff effect. The most sensitive detector system of CAST is a spin-off from space technology, a Wolter I type X-ray optics in combination with a prototype pn-CCD developed for ESA's XMM-Newton mission. As in other rare event searches, background suppression and a thorough shielding concept is essential to improve the sensitivity of the experiment to the best possible. In this context CAST offers the opportunity to study the background of pn-CCDs and its long term behavior in a terrestrial environment with possible implications for future space applications. We will present a systematic study of the detector background of the pn-CCD of CAST based on the data acquired since 2002 including preliminary results of our background simulations.Comment: 11 pages, 8 figures, to appear in Proc. SPIE 5898, UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XI

Discovery of a Novel Selective Kappa-Opioid Receptor Agonist Using Crystal Structure-Based Virtual Screening

Kappa-opioid (KOP) receptor agonists exhibit analgesic effects without activating reward pathways. In the search for non-addictive opioid therapeutics and novel chemical tools to study physiological functions regulated by the KOP receptor, we screened in silico its recently released inactive crystal structure. A selective novel KOP receptor agonist emerged as a notable result, and is proposed as a new chemotype for the study of the KOP receptor in the etiology of drug addiction, depression, and/or pain

Ludoterapia en la rehabilitación de pacientes con enfermedades mentales.

El presente trabajo titulado “Ludoterapia en la rehabilitación de pacientes con enfermedades mentales”; tiene como objetivo incorporar actividades de ludoterapia  en su función rehabilitadora en los pacientes  del hospital psiquiátrico  de la Isla de la Juventud con el fin de mejorar los estados psíquicos conductuales, la salud, la calidad de vida y hacer más placentera la vida colectiva en la institución.Durante el desarrollo del mismo se emplean los métodos de investigación teóricos (histórico lógico, análisis–síntesis y documental) y empíricos (observación y la entrevista). Estos permiten enfrentar las diferentes situaciones investigativas que se presentan durante todo el período de diagnóstico y puesta en práctica de las actividades de ludoterapia (torneos lúdicos, talleres lúdicos y exposición de medios).La muestra es de 19 pacientes lo  que representa el 100% de la población y un equipo  multidisciplinarios compuesto por 5 personas: psicólogo, rehabilitador, trabajadora social, técnico de la Cultura Física y técnico de recreación.Los resultados obtenidos nos permitió concluir que las actividades de ludoterapia seleccionadas (torneos lúdicos, talleres lúdicos y exposiciones de medios lúdicos) permiten la rehabilitación de pacientes con enfermedades mentales  en  el hospital psiquiátrico  de la Isla de la Juventud; y mejorar las relaciones interpersonales y sociales, la pertinencia al centro, su estado de salud y calidad de vida de manera general

Rapid microwave-assisted synthesis of saponites and their use as oxidation catalysts

Saponites containing divalent Mg, Ni, or Fe as octahedral cations and trivalent Al and Fe substituting Si in the tetrahedral sheet were synthesized using microwave radiation. Saponite with a high specific surface area was obtained in all the syntheses, although Fe-Al saponite crystallized was impurified by Fe2O3 and analcime. The catalytic activity of the solids for the epoxidation of (Z)-cyclooctene by hydrogen peroxide was tested, the solids obtained being highly active (conversion up to 8.8%, and 100% selectivity to the epoxide

Structural, textural and acidic properties of Cu-, Fe- and Cr-doped Ti-pillared montmorillonites

Montmorillonite has been treated with Ti-based solutions, alone or doped with Cu2 +, Fe3 + or Cr3 + cations, yielding new intercalated solids, which have been calcined at various temperatures to test the stability of the so-formed pillars. The solids calcined at 500 °C were fully characterized by chemical analysis, X-ray diffraction, FT-IR spectroscopy, thermal analyses, nitrogen adsorption and acidity evaluation. The evolution of the specific surface area, porosity and acidic properties is discussed, analysing the effect of pillaring and doping procedures on these propertie

Human body tracking by monocular vision

This article describes a tracking method of 3D articulated complex objects (for example, the human body), from a monocular sequence of perspective images . These objects and their associated articulations must be modelled . The principle of the method is based on the interpretation of image features as the 3D perspective projections points of the object model and an iterativ e Levenberg-Marquardt process to compute the model pose in accordance with the analysed image . This attitude is filtered (Kalman filter) to predict the model pose relative to the following image of the sequence . The image features are extracted locally according to the computed prediction . Tracking experiments, illustrated in this article by a cycling sequence, have been conducted to prove the validity of the approach.Cet article décrit une méthode de suivi d'objets 3D articulés, de forme complexe telle que les membres du corps humain, à partir d'une séquence monoculaire d'images perspectives. Ces objets devront être préalablement modélisés ainsi que les articulations associées. Le principe de la méthode est basé sur l'interprétation de points caractéristiques dans l'image comme étant les projections perspectives de points 3D liés au modèle de l'objet et d'un processus itératif fondé sur la méthode de Levenberg-Marquardt pour calculer l'attitude de ce modèle conforme à l'image analysée. Cette attitude et la covariance associée sont fournies à un filtre de Kalman de haut niveau pour prédire l'attitude du modèle relative à l'image suivante de la séquence. L'extraction de primitives s'effectue localement par prise en compte de la prédiction obtenue. Des expérimentations de suivi, illustrées dans cet article par une séquence de pédalage, ont été effectuées, prouvant ainsi la validité de l'approche