Simulations of Melting of Encapsulated CaCl2·6H2O for Thermal Energy Storage Technologies

We present in this work simulations using the finite difference approximation in 2D for the melting of an encapsulated phase-change material suitable for heat storage applications; in particular, we study CaCl2·6H2O in a cylindrical encapsulation of internal radius 8 mm. We choose this particular salt hydrate due to its availability and economic feasibility in high thermal mass building walls or storage. Considering only heat conduction, a thermostat is placed far from the capsule, providing heat for the melting of the phase-change material (PCM), which is initially frozen in a water bath. The difference in density between the solid and liquid phases is taken into account by considering a void in the solid PCM. A simple theoretical model is also presented, based on solving the heat equation in the steady state. The kinetics of melting is monitored by the total solid fraction and temperatures in the inner and outer surfaces of the capsule. The effect of different parameters is presented (thermostat temperature, capsule thickness, capsule conductivity and natural convection in the bath), showing the potential application of the method to select materials or geometries of the capsule

Necesidad de regular el comercio de los vehículos siniestrados para evitar el mal uso de sus números de identidad vehicular

Esta investigación tiene como objetivo determinar si la suspensión de la partida registral de los vehículos siniestrados que son comercializados evitará el mal uso de sus números de identidad vehicular. Como metodología, tipo y diseño de investigación tiene la aplicada, cualitativa, utilizándose la teoría fundamentada y estudio de casos, como participantes a policías especializados en investigación criminal y peritos en identificación vehicular. Como técnica de recolección de datos e instrumentos, la entrevista, análisis de documentos, guía de entrevista y guía de análisis de documentos. Como método de análisis se utilizó el deductivo y la síntesis, obteniéndose los resultados siguientes: no existe ninguna entidad que controle el comercio de esos vehículos, tampoco un control de la forma como son reparados-, ni información accesible sobre esos vehículos y si se evidencia un mal uso de ellos en varios casos, llegándose a la conclusión de que el comercio de vehículos siniestrados declarados a pérdida total por las compañías aseguradoras, en las actuales circunstancias, no cuenta con un marco normativo que lo regule, situación que es aprovechada por organizaciones criminales que los adquieren para “blanquear” y vender vehículos robados o por personas inescrupulosas para repararlos con accesorios o autopartes de procedencia ilícita y después comercializarlo

Isolation and identification of acetic acid bacteria in artisan sourdough

Motivation: In recent years the production of bakery products with sourdough is increasingly successful due to consumer demand for more natural, tasty and healthy products (1). Sourdoughs are a mixture of flour and water in which a very complex biological ecosystem is developed, consisting mainly of lactic acid bacteria and yeasts. However, in the last decade, it has been discovered that acetic acid bacteria are also part of this microbial consortium, although there is little information on their importance in the development of the sourdoughs and their role in the final bakery product (2,3). For this reason, this project aims to isolate and identify acetic acid bacteria from bakery sourdoughs from Andalusian artisan bakeries with the aim of studying the genera and species that comprise it.Methods: To isolate acetic acid bacteria from sourdough a culture-dependent microbiological analysis was performed from a sample of artisan sourdough. Appropriate dilutions were plated in two different culture media and grown at 30°C for 72 hours under aerobic conditions. Cell concentration was calculated as CFU/g of sourdough. The morphology of the colonies was studied by a Gram stain and a catalase assay was performed. For those Gram-negative and catalase positive, a molecular identification was carried out, extracting the DNA according to the protocol described by Cold Spring Harbor Laboratory (4). A REP-PCR was performed with oligo (GTG)5 (5) to group the candidate bacteria according to their pattern of bands and, subsequently, a 1,5kb fragment of the gene encoding the 16S rRNA was amplified with the oligonucleotides f27 and pH (6) for a pair of candidates of each pattern and sent to an external company for sequencing.Results and conclusions: It has been proven that the most appropriate culture medium for the isolation of acetic acid bacteria is the one that contains ethanol, acetic acid, an antibiotic and an antifungal in its composition. The concentration of acetic acid bacteria obtained in a solid bakery sourdough was 1,16 ∙ 10^4 CFU/g. The colonies obtained have been found to be catalase positive and Gram-negative and a REP-PCR was performed, managing to group the candidates into at least 5 different groups according to their pattern of bands. The poster will present the results of the identification by sequencing of a couple of candidates from each group, with the aim of studying which genera of acetic acid bacteria are present in the studied sourdough

TRIBUNAL ARBITRAL DE SCHRADER CAMARGO INGENIEROS ASOCIADOS S.A. VS. REFINERÍA DE CARTAGENA S.A.- REFICAR

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Las áreas de contenido, dominios cognitivos y nivel de desempeño del aprendizaje de la Matemática en la educación primaria

La evaluación de la calidad de la educación es un proceso en el que se involucran los estudiantes, los docentes, la familia y la sociedad. Decir que se posee un alto índice de calidad en la educación requiere de la aplicación de instrumentos que demuestren las competencias y desempeños de los factores antes mencionados. Los maestros, como un eslabón importante en esta cadena, necesitan conocer los presupuestos teóricos que sustentan dicha evaluación; en tal sentido, el artículo refiere por los autores una reflexión a partir del estudio de documentos de organismos internacionales como la ONU y la UNICEF así como de los diferentes grupos de trabajos sobre evaluación de la calidad de la educación, en la asignatura de Matemática, donde se resumen importantes presupuestos

Vegetation establishment in soils polluted by heavy metal(loid)s after assisted natural remediation

Background and aims This field-base study evaluates the long-term effectiveness of in-situ remediation measures applied to soils residually polluted by potentially toxic elements (PTEs) in an area affected by a mining spill in SW Spain. Methods To evaluate the remediation treatments success, their influence on key soil properties and on the development of spontaneous vegetation in the treated soils was investigated. The treatments were based on human derived by-products valorization, and consisted of: biopiles, marble sludge and gypsum mining spoil addition, and their combination with an organic amendment (vermicompost). Results Amendments application improved the soil properties and reduced PTEs availability. As a result, an enhancement in spontaneous development of vegetation cover and diversity of plant species in the treated soils was followed. Spergularia rubra and Lamarckia aurea, two primary plant species growing in the studied area and that exhibit strong association to soils with the highest levels of pollution, showed high Pb and As accumulation in shoots ande in roots. Exceptionally, accumulation of these pollutants occurred in L. aurea roots, which can explain its high presence in soils with more limited vegetation development and in which no additional plant species can thrive. Conclusions The occurrence of S. rubra and L. aurea in the amended soils may be indicative of improved soil conditions and reduced toxicity induced by the remediation measures implemented. They may also be considered key species in the area since their presence can promote the recolonization of the degraded soils by species less tolerant to their residual pollution

Ecotoxicological Assessment of Polluted Soils One Year after the Application of Different Soil Remediation Techniques

This research was funded by the project RTI 2018-094327-B-I00 (Spanish Ministry of Science and Innovation) and by the project E-RNM-444-UGR20 (Operating Research Program FEDER 2014- 2020). The APC was funded by E-RNM-444-UGR20.The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/toxics11040298/s1, Table S1: Guideline values (mg/kg) to declare a soil as potentially polluted by legislations of different countries [51–54,90]The present work evaluated the influence of eight different soil remediation techniques, based on the use of residual materials (gypsum, marble, vermicompost) on the reduction in metal(loid)s toxicity (Cu, Zn, As, Pb and Cd) in a polluted natural area. Selected remediation treatments were applied in a field exposed to real conditions and they were evaluated one year after the application. More specifically, five ecotoxicological tests were carried out using different organisms on either the solid or the aqueous (leachate) fraction of the amended soils. Likewise, the main soil properties and the total, water-soluble and bioavailable metal fractions were determined to evaluate their influence on soil toxicity. According to the toxicity bioassays performed, the response of organisms to the treatments differed depending on whether the solid or the aqueous fraction was used. Our results highlighted that the use of a single bioassay may not be sufficient as an indicator of toxicity pathways to select soil remediation methods, so that the joint determination of metal availability and ecotoxicological response will be determinant for the correct establishment of any remediation technique carried out under natural conditions. Our results indicated that, of the different treatments used, the best technique for the remediation of metal(loid)s toxicity was the addition of marble sludge with vermicompost.Ministry of Science and Innovation, Spain (MICINN) Spanish Government RTI 2018-094327-B-I00Operating Research Program FEDER 2014-2020 E-RNM-444-UGR2

Rugulopteryx okamurae: Effect of hydrothermal acid pretreatment on the saccharification process

The biological invasion caused by the invasive macroalga Rugulopteryx okamurae is causing increasing concern in southern Europe. To reduce its impact, this brown alga can be treated from a biorefinery approach. In this study, the macroalga is used as raw material to obtain fermentable sugars, which can be converted into high-value-added products. The alga was exposed to hydrothermal and hydrothermal acid pretreatment and the pretreated biomass was used for enzymatic hydrolysis, achieving a hydrolysate with a reducing sugar concentration of almost 25 g/L (49.2% more than with non-pretreated alga). In addition, the combined severity factor was calculated to identify the best pretreatment conditions, finding the optimum in those pretreatments performed with 0.2 N HCl concentration and 15 min reaction time. Based on the results, it would be interesting to carry out new studies using the saccharified medium obtained under optimal conditions to obtain value-added compounds by fermentation