Com va arribar el metall a la carretera?

Els sediments dipositats al llindar de les carreteres, dins dels quals s'han detectat grans quantitats de metalls, són un potencial risc medi ambiental donada la possible transmissió dels contaminants que contenen. Aquest treball estudia la concentració d'elements metàl·lics als sediments d'una autopista propera a Barcelona, i avalua la remobilització de metalls mitjançant el fraccionament, comparant tests d'extracció aplicats als sediments.Los sedimentos depositados en los bordes de las carreteras, dentro de los cuales se han detectado grandes cantidades de metales, son un potencial riesgo ambiental debido a la fácil transmisión de sus contaminantes. Este trabajo estudia la concentración de elementos metálicos en los sedimentos de una autopista cercana a Barcelona y evalúa su remobilización mediante fraccionamiento, al comparar las pruebas de extracción aplicadas a este tipo de depósitos.Roadside sediments, in which high amounts of sediments have been detected, are an environmental concern of great interest due to the possible transmission of their pollutants from traffic activities and road maintenance to humans and environment. This work analyzes leaching tests applied to roadside metallic sediments, in order to assess them and compare them with heavy metals remobilization by fractionation

Identificar diferents tipus de pernil amb llum sincrotró

Experiments a la instal·lació europea de radiació sincrotró de Grenoble (ESRF) estan permetent a científics de la UAB i la Universitat de la Sapienza de Roma (Itàlia) una possible identificació dels diferents tipus de pernils, segons la criança i l'alimentació del porc i el procés de curació. És el primer cop que aquest producte s'estudia amb radiació sincrotró.Experimentos en la instalación europea de radiación sin crotrón deGrenoble (ESRF) están permitiendo a científicos de la UAB y laUniversidad de la Sapienza en Roma (Italia) una posible identificación de los diferentes tipos de jamones según la crianza y alimentación del cerdo y el proceso de curación. Es la primera vez que este producto se estudia con radiación sin crotrón.Experiments at the European Synchrotron Radiation Facility (ESRF)allow researchers from Universitat Autònoma de Barcelona and Sapienza University of Rome, Italy, to discover ways of identifying different types of ham according to what pigs are fed and curing processes. It is the first time this product is studied with synchro tronradiation

Determination of phytic acid in urine by inductively coupled plasma mass spectrometry

The aim of this work is to provide a simple and accurate analytical procedure to easily determine phytic acid in urine, in contrast with time-consuming current method

Inhibidores de la litiasis oxalocálica. Efectos de sus interacciones en la cristalización de oxalato cálcico

Estudiar de manera sistemática el efecto in vitro de diversas sustancias con pretendidas propiedades inhibidoras sobre la cristalización de oxalato cálcico, haciendo especial énfasis en el efecto de sus interacciones sobre la inhibición. Dichas interacciones son susceptibles de modificar de manera importante el carácter inhibidor de una determinada sustancia, produciendo tanto efectos positivos (sinérgicos) como negativos en la prevención de la cristalizació

Un sistema innovador i econòmic elimina l'arsènic en aigües contaminades

El Grup de Tècniques de Separació (GTS) de la UAB, juntament amb Leitat Technological Center, ha desenvolupat el projecte AsFree per obtenir un sistema innovador i econòmic de filtració d'efluents contaminats amb arsènic. Els investigadors han aconseguit una millora de fins a un 600% en l'eficiència del sistema de depuració.El Grupo de Técnicas de Separación (GTS) de la UAB, junto con Leitat Technological Center, ha desarrollado el proyecto AsFree para obtener un sistema innovador y económico de filtración de efluentes contaminados con arsénico. Los investigadores han conseguido una mejora de hasta un 600% en la eficiencia del sistema de depuración

Efficient arsenic(V) and arsenic(III) removal from acidic solutions with Novel Forager Sponge-loaded superparamagnetic iron oxide nanoparticles

Nowadays, there is awidevariety of arsenic decontamination processes being adsorption processes themost efficient. In this concern, superparamagnetic iron oxide nanoparticles (SPION) have been proposed as an appropriate system to improve arsenic adsorption from acidic wastewater. The number of mines, the amount of ore processed, and thus the amount of mine (acid) wastewaters have been rapidly increased in recent decades. For this reason, arsenic removal from contaminated water is an important goal to accomplish environmental regulations. It is noteworthy that aggregation of these nanoparticles has been detected as the maindifficulty, hindering thepromising adsorption. In order toovercomethis drawback, it is proposed a system to avoid aggregation based on nanoparticles dispersion into an appropriate supporting material. To this purpose, SPION have been fixed on a cellulosic sponge achieving a decrease of the aggregation state, an increase of the active centers, and consequently, arsenic adsorption increases. Experimental results report a lower aggregation of supported SPION over sponge than the observed in the non supported nanoparticles. At this point, a remarkable improvement in the sponge system adsorption capacity is observed in comparison with superparamagnetic nanoparticles in suspension, reaching adsorption capacities about 2.1 mmol As/g SPION and 12.1 mmol As/g SPION for arsenite and arsenate, respectively at pH 3.8. Then, the developed system not only amends the aggregation problem but also keep their nanoproperties intact, making the system a suitable one for arsenic removal in acidic wastewater treatmen

The power of weak ion-exchange resins assisted by amelogenin for natural remineralization of dental enamel : an in vitro study

Acord transformatiu CRUE-CSICAltres ajuts: Sandra Diez-García acknowledges the FI-2017 fellowship from Agència de Gestió d'Ajuts Universitaris i de Recerca (Generalitat de Catalunya).This study aims to develop an innovative dental product to remineralize dental enamel by a proper combination of ion-exchange resins as controlled release of mineral ions that form dental enamel, in the presence of amelogenin to guide the appropriate crystal growth. The novel product proposed consists of a combination of ion-exchange resins (weak acid and weak base) individually loaded with the remineralizing ions: Ca, PO and F, also including Zn in a minor amount as antibacterial, together with the protein amelogenin. Such cocktail provides onsite controlled release of the ions necessary for enamel remineralization due to the weak character of the resins and at the same time, a guiding tool for related crystal growth by the indicated protein. Amelogenin protein is involved in the structural development of natural enamel and takes a key role in controlling the crystal growth morphology and alignment at the enamel surface. Bovine teeth were treated by applying the resins and protein together with artificial saliva. Treated teeth were evaluated with nanoindentation, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The innovative material induces the dental remineralization creating a fluorapatite layer with a hardness equivalent to sound enamel, with the appropriate alignment of corresponding nanocrystals, being the fluorapatite more acid resistant than the original mineral. Our results suggest that the new product shows potential for promoting long-term remineralization leading to the inhibition of caries and protection of dental structures

Enhanced arsenite removal by superparamagnetic iron oxide nanoparticles in-situ synthesized on a commercial cube-shape sponge : adsorption-oxidation mechanism

Altres ajuts: Acord transformatiu CRUE-CSICHypothesis: The easy aggregation of superparamagnetic iron oxide nanoparticles (SPION) greatly reduces their adsorption performance for removing arsenic (As) from polluted water. We propose to exploit the porosity and good diffusion properties of a cube-shaped cellulose sponge for loading SPION to reduce the aggregation and to develop a composite adsorbent in the cm-scale that could be used for industrial applications. Experiments: SPION were in-situ synthesized by co-precipitation using a commercial cube-shaped sponge (MetalZorb®) as support. The morphology, iron-oxide phase, adsorption performance and thermodynamic parameters of the composite adsorbent were determined to better understand the adsorption process. X-ray absorption spectroscopy (XAS) was used to investigate the chemical state of the adsorbed As(III). Findings: The adsorption of the supported SPION outperforms the unsupported SPION (ca. 14 times higher adsorption capacity). The modelling of the adsorption isotherms and the kinetic curves indicated that chemisorption is controlling the adsorption process. The thermodynamic analysis shows that the adsorption retains the spontaneous and endothermic character of the unsupported SPION. The XAS results revealed an adsorption-oxidation mechanism in which the adsorbed As(III) was partially oxidized to less toxic As(V) by the hydroxyl free radical (•OH) generated from Fe(III) species and by the hydroxyl groups

Outstanding performance of hierarchical alumina microspheres for boron removal in the presence of competing ions

Altres ajuts: acords transformatius de la UABDeveloping efficient materials for the removal of boron from aqueous solutions is becoming an important task to overcome boron pollution. Herein, we present hierarchical alumina microspheres (HAM) as an outstanding adsorbent, synthesized via a microwave-assisted co-precipitation method. The microstructure, morphology, and textural characterization of the HAM particles carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) revealed hollow γ-Al2O3 particles with a porous dandelion-like shape and an average size of 1.5 μm. The analysis of the adsorption data indicated that the adsorption was homogeneous in a single layer and that chemical adsorption was the controlling step in the process. The adsorption capacity obtained at an initial concentration of 800 mg·L−1 was 51.60 mg·g−1, and the theoretically calculated maximum adsorption capacity using the Langmuir model was 138.50 mg·g−1, which outperforms previously reported adsorbents. The determination of thermodynamic parameters indicated that the adsorption is an exothermic and non-spontaneous process. The XPS spectra of HAM after adsorption indicated the formation of Al-O-B bonds. Of particular interest for industrial applications, the HAM adsorbent showed excellent selectivity for boron in the presence of competing cations or anions and at different ionic strengths. In addition, HAM maintained a high adsorption capacity after five consecutive adsorption/desorption cycles. These findings highlight the potential of HAM as a highly microporous material for boron removal in real industrial applications

Què passa amb el mercuri quan arriba al terra?

Un dels elements químics més perjudicials per al medi ambient i els humans, és el mercuri, per la qual cosa resulta important analitzar en quina quantitat es troba i com es comporta una vegada arriba al terra procedent de les emissions industrials. Investigadors de la UAB han estudiat els terrenys més pròxims a una planta química de clor-àlcali ubicada a Holanda.Uno de los elementos químicos más perjudiciales para el medioambiente y los humanos es el mercurio, por lo que resulta importanteanalizar en qué cantidad se halla y cómo se comporta una vez llega alsuelo procedente de las emisiones industriales. Investigadores de laUAB han estudiado los terrenos más cercanos a una planta química decloro-álcali ubicada en Holanda