62 research outputs found

    Pyridinium-N-(2-Pyridyl)aminides: a selective approach to substituted 2-aminopyridines

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    Differently substituted 2-aminopyridines have been prepared in two steps from pyridinium-N-(2-pyridyl)aminide, by reaction with the corresponding electrophiles and reduction of the N-N bond.Ministerio de Educación y Cienci

    Simultaneous ammonium and phosphate recovery and stabilization from urban sewage sludge anaerobic digestates using reactive sorbents

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    The use of low-cost inorganic sorbents as a new sustainable strategy to enhance the valorization of nutrients (N-P-K), from the urban water cycle (e.g., side streams from sewage sludge anaerobic digestion), in agriculture applications is presented. The simultaneous recovery and stabilization of ammonium and phosphate by using a mixture of two reactive sorbents (Na and K zeolites and magnesium oxide) was evaluated. The nutrients stabilization process, favoured at alkaline pH values, is carried out by a) the precipitation of phosphate ions with magnesium and/or ammonium ions and b) the sorption of ammonium by Na- and K-zeolites. MgO(s) promoted the stabilization of phosphate as bobierrite (Mg3(PO4)2(s)) or struvite (MgNH4PO4(s)) depending on the applied dose. Doses with the stoichiometric molar ratio of Mg/P promote the formation of bobierrite, while molar ratios higher than 3 favour the formation of struvite. Na zeolites (NaP1-NA, NaP1-IQE) demonstrated efficiency on ammonium stabilization between 60±2 (for 15gZ/L) to 90±3% (for 50gZ/L). The ammonium recovery efficiency is limited by the zeolite sorption capacity. If the target of the fertilizing criteria should include K, then the use of a K-zeolite (e.g., 5AH-IQE) provides a good solution. The optimum pH for the precipitation of struvite and bobierrite is 9.5 and the optimum pH for ammonium removal is between 4 and 8.5. N is present in higher concentrations (up 0.7-1gNH4+/L) when pH is ranged between 8.2 and 8.6. The ammonium recovery ratios were better than those previously reported using only magnesium oxide or even a more expensive reagent as newberrite (MgHPO4(s)). The recovery mechanisms described generate low-solubility stabilized nutrients forms that potentially can be applied as slow-release fertilizers in agriculture. Thus, the use in agriculture of blends of digested sludge with low-solubility stabilized nutrients forms will improve soils quality properties in terms of organic matter and nutrients availability

    Weak pressure gradient over the Iberian Península and African dust outbreaks: a new dust long transport scenario

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    African dust outbreaks over the Iberian Peninsula have been related to four synoptic patterns responsible for the advection of dust: 1. A North African high located at surface level. 2. An Atlantic depression centered over northwestern Africa, western Iberia or the southwest of the Portuguese coast with an associated high or ridge over the Mediterranean Sea. 3. A North African depression. 4. A North African high located at upper levels. Consequently, particulate matter (PM) levels in Iberia are expected to rise when any of these atmospheric synoptic scenarios prevail. Nevertheless, PM levels might not increase due to wet deposition, as Spain receives the most African-derived dust rain events of any European country. In this study, a meteorological scenario different than the above situations is evaluated

    Ahora / Ara

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    La cinquena edició del microrelatari per l’eradicació de la violència contra les dones de l’Institut Universitari d’Estudis Feministes i de Gènere «Purificación Escribano» de la Universitat Jaume I vol ser una declaració d’esperança. Aquest és el moment en el qual les dones (i els homes) hem de fer un pas endavant i eliminar la violència sistèmica contra les dones. Ara és el moment de denunciar el masclisme i els micromasclismes començant a construir una societat més igualitària. Cadascun dels relats del llibre és una denúncia i una declaració que ens encamina cap a un món millor

    Late and postmagmatic alterations in the tin-bearing batholith of Ricobayo (Iberian Massif, NW Spain)

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    The deuteric alteration processes undergone by the granites of the Ricobayo Batholith were: microclinization, chloritization, albitization, muscovitization, tourmalinization and garnetization. These processes must be interpreted in a dynamic context so that the different reactions that take place are the consequence of a successive interaction between rock and fluids. The physicochemical conditions deduced from these fluids are: temperature lower than 600 OC, pressure between 1.5 and 1 Kb, fugacity of oxygen between 10-25 and 10-35 bars, fugacity of sulphur lower than 10-l5 bars, the composition was kept stable and their log (a(K+)/a(Ht)) and log (a(Na+)/a(H+)) varied between 3.8 and 3.2 and between 3.5 and 4.6, respectively, and the pH of the fluids was higher than 5 during the microclinization, muscovitization and tourmalinization, and lower during chloritization and albitization. The deposition of cassiterite occurs with pH episodes that exceed 5

    A Comparative Analysis of Machine Learning Techniques for Muon Count in UHECR Extensive Air-Showers

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    The main goal of this work is to adapt a Physics problem to the Machine Learning (ML) domain and to compare several techniques to solve it. The problem consists of how to perform muon count from the signal registered by particle detectors which record a mix of electromagnetic and muonic signals. Finding a good solution could be a building block on future experiments. After proposing an approach to solve the problem, the experiments show a performance comparison of some popular ML models using two different hadronic models for the test data. The results show that the problem is suitable to be solved using ML as well as how critical the feature selection stage is regarding precision and model complexity.Spanish Ministry of Economy and Competitiveness-MINECO FPA2015-70420-C2-2-R FPA2017-85197-P RTI2018-101674-B-I00European Union (EU) FPA2015-70420-C2-2-R FPA2017-85197-P RTI2018-101674-B-I0

    Book reviews

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    Recensiones de libros de antropología publicados últimamente.Books reviews on anthropological publications.Grupo de Investigación Antropología y Filosofía (SEJ-126). Universidad de Granad

    Book reviews

    No full text
    Recensiones de libros de antropología publicados últimamente.Books reviews on anthropological publications.Grupo de Investigación Antropología y Filosofía (SEJ-126). Universidad de Granad

    Late and postmagmatic alterations in the tin-bearing batholith of Ricobayo (Iberian Massif, NW Spain)

    No full text
    The deuteric alteration processes undergone by the granites of the Ricobayo Batholith were: microclinization, chloritization, albitization, muscovitization, tourmalinization and garnetization. These processes must be interpreted in a dynamic context so that the different reactions that take place are the consequence of a successive interaction between rock and fluids. The physicochemical conditions deduced from these fluids are: temperature lower than 600 OC, pressure between 1.5 and 1 Kb, fugacity of oxygen between 10-25 and 10-35 bars, fugacity of sulphur lower than 10-l5 bars, the composition was kept stable and their log (a(K+)/a(Ht)) and log (a(Na+)/a(H+)) varied between 3.8 and 3.2 and between 3.5 and 4.6, respectively, and the pH of the fluids was higher than 5 during the microclinization, muscovitization and tourmalinization, and lower during chloritization and albitization. The deposition of cassiterite occurs with pH episodes that exceed 5
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