252 research outputs found

    Two-step persulfate and Fenton oxidation of naphthenic acids in water

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    WILEY: "This is the peer reviewed version of the following article: Journal of Chemical Technology and Biotechnology 93 (2018): 2262-2270, which has been published in final form at http://doi.org/10.1002/jctb.5569. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."BACKGROUD: In the current study, two-step persulfate and Fenton oxidation has been investigated for the mineralization of naphthenic acids at 80 °C and initial pH ≈ 8. This pH evolves during the persulfate oxidation step towards the optimum for Fenton oxidation (≈ 3). The effects of persulfate and H2O2doses, iron concentration, duration of the persulfate oxidation step and operating temperature have been assessed. RESULTS: The combined treatment allowed up to ≈ 80% mineralization of cyclohexanoic acid using fairly low relative amounts of reagents (20 and 30% of the stoichiometric for persulfate and H2O2, respectively). For mineralization of cyclohexanoic acid, 115 and 87 kJ mol-1were obtained as representative values of the apparent activation energy for the persulfate and Fenton oxidation steps, respectively. The system was also successfully tested with other naphthenic acids, including cyclohexanebutyric acid, 2-naphthoic acid and 1,2,3,4-tetrahydro-2-naphthoic acid. Treatment of the naphthenic acids tested by this system gave rise to easily biodegradable effluents consisting mainly of short-chain organic acids. The biodegradability was confirmed by the BOD5/COD ratio and respirometric tests. CONCLUSION: The results show the potential application of this approach as a promising cost-effective solution for the treatment of naphthenic acids-bearing aqueous wastes. This approach has significant advantage compared with the single thermally-activated persulfate or Fenton oxidation, since it allows a high mineralization at reduced reagent cost upon replacing part of the persulfate by less expensive H2O2.We are grateful to the Chinese Scholarship Council (CSC) for supporting the Ph.D. program of Xiyan Xu (CSC, File No. 201308410047). Spanish MINECO is also gratefully acknowledged for the financial support through the project CTQ2013-41963-

    Application of intensified Fenton oxidation to the treatment of hospital wastewater: Kinetics, ecotoxicity and disinfection

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    Fenton oxidation has proved to be effective for the treatment of a real hospital wastewater. The intensification of the process viz. the improvement on the efficiency of H2O2consumption, by increasing the temperature, is necessary to operate in a single step and avoid high reaction times and the need of large H2O2 and iron concentrations. This approach would allow taking advantage of the heat energy contained in the laundry stream since the washing process is performed at high temperature to assure disinfectionof the hospital textiles. In this work, temperatures within the range of 50-90 °C have been tested, which allowed an effective oxidation of the real wastewater ([COD]0 = 365 mg L-1, [Phenols]0 = 8.4 mg L-1, [total coliforms]0 = 4.16 × 106 MPN/100 mL, 5 toxicity units) with the stoichiometric amount of H2O2 (1000 mg L-1) and a relatively low iron concentration (25 mg L-1 Fe3+). Operating at 90 °C, complete disappearance of phenolic compounds and 70% and 50% reduction of COD and TOC were achieved in 1 h reaction time. Time evolution of those global parameters were appropriately fitted to pseudo-first and second order kinetic equations, providing a useful approach for design purposes. The main by-products were short-chain organic acids (oxalic and formic), being the final effluents non-toxic. Disinfection of the hospital wastewater was also achieved at all the operating temperatures tested, as confirmed by the absence of coliformsThis research has been supported by the CM through the project S2013/MAE-2716 and by the Spanish MINECO through the project CTQ2013-41963-R. M. Munoz thanks the Spanish MINECO for a Juan de la Cierva-Incorporación postdoctoral contract (IJCI-2014-19427

    dReDBox: Materializing a full-stack rack-scale system prototype of a next-generation disaggregated datacenter

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    Current datacenters are based on server machines, whose mainboard and hardware components form the baseline, monolithic building block that the rest of the system software, middleware and application stack are built upon. This leads to the following limitations: (a) resource proportionality of a multi-tray system is bounded by the basic building block (mainboard), (b) resource allocation to processes or virtual machines (VMs) is bounded by the available resources within the boundary of the mainboard, leading to spare resource fragmentation and inefficiencies, and (c) upgrades must be applied to each and every server even when only a specific component needs to be upgraded. The dRedBox project (Disaggregated Recursive Datacentre-in-a-Box) addresses the above limitations, and proposes the next generation, low-power, across form-factor datacenters, departing from the paradigm of the mainboard-as-a-unit and enabling the creation of function-block-as-a-unit. Hardware-level disaggregation and software-defined wiring of resources is supported by a full-fledged Type-1 hypervisor that can execute commodity virtual machines, which communicate over a low-latency and high-throughput software-defined optical network. To evaluate its novel approach, dRedBox will demonstrate application execution in the domains of network functions virtualization, infrastructure analytics, and real-time video surveillance.This work has been supported in part by EU H2020 ICTproject dRedBox, contract #687632.Peer ReviewedPostprint (author's final draft

    Paleogeografía sísmica de zonas costeras en la Península Ibérica: su impacto en el análisis de terremotos antiguos e históricos en España

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    This paper presents three examples of ancient earthquakes occurring in coastal areas of the S and SE of the Iberian Peninsula (218 BC, AD 40-60 and AD 1048) with the aim of illustrating the use of geological and archaeological data in their macroseismic characterization. Historical information for ancient earthquakes that occurred in Spain prior to the 10th century is scarce or non-existent. This paper shows that the current state of knowledge on palaeoseismology and archaeoseismology on these ancient events clearly exceeds the existing historical information allowing the increase of macroseismic information points by using the ESI-07 scale (Environmental Seismic Intensity). Consequently, the geologic analyses of ancient earthquakes contribute to their understanding and parametric evaluations, and improve further advances in seismic hazard assessments. The most significant issue outlined in the present paper is the analysis of the ancient palaeogeography of the affected areas. The studied examples analysed were located in open estuarine areas that have been filled by fluvial sediments or anthropogenic fills over time. The effects of the 218 BC earthquake-tsunami event in the Gulf of Cadiz are analysed in estuarine areas, and especially in the ancient Roman Lagus Ligustinus (Guadalquivir Depression marshes); the effects of the earthquake in AD 40-60 is analysed in the old Roman city of Baelo Claudia located in the Bolonia Bay (Strait of Gibraltar); and the effects of the earthquake of AD 1048on the ancient Sinus Ilicitanus (Bajo Segura Depression) during Muslim times. Descriptions from Roman and Arabic geographers are cross-checked with existing palaeogeographic models based on geological data. This type of analysis results in ancient macroseismic scenarios for the interpretation of theoretical distributions of intensities and environmental effects supporting the concept of “seismic palaeogeography” proposed in this paperEl presente trabajo recoge tres ejemplos de terremotos antiguos (218 AC, 40-60 AD y 1048 AD) ocurridos en zonas litorales del S y SO de la Península Ibérica con la intención de ilustrar el uso de datos geológicos y ar¬queológicos en la caracterización macrosísmica de los mismos. En la mayor parte de los sísmos ocurridos con anterioridad al siglo X d.C. la información documental histórica que se posee es muy escasa o inexistente. El presente trabajo muestra que el actual estado de conocimiento en paleosismología y arqueosismologia sobre este tipo de terremotos sobrepasa con creces la información documental histórica, permitiendo la multiplica¬ción de los puntos de información macrosísmica mediante el uso de la escala ESI-07 (Environmental Seismic Intensity). Consecuentemente, el análisis geológico de los terremotos antiguos mejora su conocimiento y análisis paramétrico, permitiendo avanzar la evaluación de la peligrosidad sísmica de las zonas afectadas. El aspecto que se pone de especial relieve en este trabajo es el análisis de la paleogeografía existente en la antigüedad, ya que todas las zonas (afectadas) analizadas en este trabajo corresponden a zonas estuarinas abiertas que se han ido rellenado por aportes fluviales o de forma artificial con el tiempo. Se analizan los efectos del terremoto de 218 AC en las zonas estuarinas del Golfo de Cádiz y muy especialmente en el antiguo Lacus Ligustinus (marismas del Guadalquivir) durante época romana; los efectos del terremoto de 40-60 AD en la antigua Bahía de Baelo Claudia (Estrecho de Gibraltar); y los efectos del terremoto de 1048 AD en el antiguo Sinus ilicitanus (Depresión del Bajo Segura) durante época musulmana. Se han cotejado descripciones de geógrafos romanos y árabes con modelos basados en datos geológicos. Este tipo de análisis ha permitido generar antiguos escenarios macrosísmicos basados en la paleogeografía y reinterpretar las distribuciones teóricas de intensidades y los efectos ambientales de los terremotos estudiados que es a lo que se refiere el concepto de “paleogeografía sísmica” propuesto en este trabajoThis work has been funded by the Spanish-FEDER research projects CGL2012-37281 C02.01 (QTECTBETICA-USAL), CGL2012-33430 (CSIC) and CGL2013-42847-R (UNED

    Physical Activity Adherence Related to Body Composition and Physical Fitness in Spanish Older Adults: 8 Years-Longitudinal EXERNET-Study

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    Introduction: The multiple benefits of physical activity (PA) compared to the current lack of adherence to this behavior in older people makes it necessary to identify the factors related to its long-term dropout, therefore, the aim of this study was: (i) to study the evolution of behavior change for PA through stages of change (SoC) after 8 years and, to identify the associated factors related to the worsening of SoC for PA. Methods: A total of 714 Spanish older adults (>65 years) participated in the Longitudinal elderly EXERNET study 8 years follow-up. SoC for PA from Transtheoretical model of behavior change (TTM), body composition BMI, fat mass, lean mass, waist circumference (WC), and hip circumference (HC)] and physical fitness (EXERNET battery fitness tests) were recorded. A multivariate binary logistic regression model was used to identify the potential predictive factors of worsening SoC for PA. Results: Three hundred and sixty participants (50.4%) worsening their SoC for PA after 8 years. Predictors factors associated with worsening of SoC were: HC (OR = 1.022; 95% CI: 1.001, 1.044), Lower body strength (OR = 0.940; 95% CI: 0.887, 0.997) and aerobic endurance at the 6 min-walk test (OR = 0.997; 95% CI: 0.995, 0.999). Conclusion: This study highlights that we need to identify adults with high HC, lower body strength and lower aerobic endurance to design a tailored PA program. Identifying the determinants of losing adherence to PA will help in the creation, design, and evaluation of exercise programs with the goal of reducing older adults’ drop-outs rates. Copyright © 2022 Jiménez-Zazo, Hernández-Martínez, Romero-Blanco, Cabanillas, Pérez-Gómez, Ara, Casajús, Vicente-Rodríguez, Gesteiro, González-Gross and Aznar

    Coseismic VS climatic effects in the record of relative sea-level changes: an example from last interglacials in SE Spain.

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    Trying to decipher how palaeoseismic activity has influenced the altitudinal disposition of interglacial deposits is one of the main challenges that must be achieved in order to quantify relative sea-level changes between consecutive highstands. Likewise, identifying palaeoseismic features in an area with low instrumental seismic activity can implement the seismic record and contribute to better seismic hazard knowledge. In this sense, Cope basin (SE Spain) becomes a reference basin to undertake this kind of analysis, firstly because of excellent outcrop conditions and secondly because the sea-level record is undoubtedly conditioned here by both effects: climatically driven changes and local and regional seismotectonics

    Psychosocial factors related to physical activity in frail and prefrail elderly people

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    Background: Increased physical activity (PA) is a very important factor in a healthy aging lifestyle. Psychosocial factors have also a main role in the initiation and maintenance of this behavior, but nowadays its implications for frailty elderly people are unknown, therefore, the aim of this study was to identify the psychosociological variables of behavior change that influence the practice of (PA) in frail and prefrail elderly. Methods: A total of 103 frail and pre-frail elderly people (72 females) participated in this cross-sectional study, on the framework of the EXERNET-Elder3.0 project. Age ranged from 68–94 years (mean = 80.4 ± 5.9 years). Individualized face-to-face interviews according to the constructs of the Transtheoretical Model of Change (TTM) (decisional balance (DB) and self-efficacy (SE)], social support (SS) (family and friends) and outcome expectations (OE) were administered to all participants. Results: Significant differences were found in DB, perceived benefits (PBn), SE, family-related SS and OE as a function of stages of change (SoC) (p < 0.005), but no significant were found in perceived barriers (PBrr) (p = 0.259) and friends-related SS (p = 0.068). According to the Scheffé post-hoc test, those in advanced SoC (Action-Maintenance), scored higher than those in lower SoC (Precontemplation-Contemplation and Preparation). Conclusion: The scores obtained from the study variables differed according to the SoC, supporting the external validity for the use of the TTM in frailty elderly. Further research is needed to determine the impact of PBrr and friends-related SS on this people, as well as to identify the validity of this model in the long-term in this population

    BiOnt: Deep Learning using Multiple Biomedical Ontologies for Relation Extraction

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    Successful biomedical relation extraction can provide evidence to researchers and clinicians about possible unknown associations between biomedical entities, advancing the current knowledge we have about those entities and their inherent mechanisms. Most biomedical relation extraction systems do not resort to external sources of knowledge, such as domain-specific ontologies. However, using deep learning methods, along with biomedical ontologies, has been recently shown to effectively advance the biomedical relation extraction field. To perform relation extraction, our deep learning system, BiOnt, employs four types of biomedical ontologies, namely, the Gene Ontology, the Human Phenotype Ontology, the Human Disease Ontology, and the Chemical Entities of Biological Interest, regarding gene-products, phenotypes, diseases, and chemical compounds, respectively. We tested our system with three data sets that represent three different types of relations of biomedical entities. BiOnt achieved, in F-score, an improvement of 4.93 percentage points for drug-drug interactions (DDI corpus), 4.99 percentage points for phenotype-gene relations (PGR corpus), and 2.21 percentage points for chemical-induced disease relations (BC5CDR corpus), relatively to the state-of-the-art. The code supporting this system is available at https://github.com/lasigeBioTM/BiOnt.Comment: ECIR 202

    Sea level and climate changes during OIS 5e in the Western Mediterranean

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    Palaeontological, geomorphological and sedimentological data supported by isotopic dating on Oxygen Isotopic Stage (OIS) 5e deposits from the Spanish Mediterranean coast, are interpreted with the aim of reconstructing climatic instability in the Northern Hemisphere. Data point to marked climatic instability during the Last Interglacial (OIS 5e), with a change in meteorological conditions and, consequently, in the sedimentary environment. The oolitic facies generated during the first part of OIS 5e (ca. 135 kyr) shift into reddish conglomeratic facies during the second part (ca. 117 kyr). Sea surface Temperature (SST) and salinity are interpreted mainly on the basis of warm Senegalese fauna, which show chronological and spatial differential distribution throughout the Western Mediterranean. Present hydrological and meteorological conditions are used also as modern analogues to reconstruct climatic variability throughout the Last Interglacial, and this variability is interpreted within the wider framework of the North Atlantic record. All the available data indicate an increase in storminess induced by an increase in the influence of northwesterlies, a slight drop of SST in the northern Western Mediterranean, and an important change in meteorological conditions at the end of OIS 5e (117 kyr). These changes correlate well with the decrease in summer insolation and with the climatic instability recorded in North Atlantic high latitudes

    Registro de los cambios del nivel del mar durante el cuaternario en las Islas Canarias Occidentales (Tenerife y La Palma)

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    Deposits and erosional marine features representing Quaternary interglaciars interstadials have been analyzed based on geological mapping, sedimentological and paleontological studies. Isotopic measurements and aminoacid racemization dating have been used for chronological purpose. The most complete marine sequence consists of five marine terraces at elevation between O m and 18 m above mean sea leve1 (asl) in Tenerife, where deposits of the Last Interglacial (01s 5e) include Strombus bubonius and «Senegalese» fauna. For La Palma only preliminary results are presented, but two clear marine levels can be distinguished in the Northeast coast at elevation between O m and 4 m asl; the most recent is Holocene, and the oldest, probably, developed during the Last Interglacial. The rate of vertical movements for the last -135,000 years has been calculated for both Islands, the values show a gently subsiding trend in Tenerife and a gently uplifting trend in La Palma.Depósitos y superficies de erosión asociados a los períodos interglaciares o interestadiales cuaternarios, han sido analizados utilizando cartografías ~eomorfológicas, datos sedimentológicos y paleontológicos. Medidas isotópicas ( 14C y Th/U) y datos de racemización de aminoácidos, a partir de las conchas de los moluscos, han sido utilizados con fines cronológicos. La secuencia marina más completa se desarrolla en la isla de Tenerife, y consiste en cinco terrazas marinas localizadas entre los O y 18 m (por encima del nivel medio del mar); en esta misma isla los depósitos del Ultimo Interglacial (01s 5e) incluyen Strombus bubonius y fauna «senegalesa». Los datos sobre la isla de La Palma son preliminares, aunque dos niveles marinos diferentes pueden ser claramente diferenciados entre las cotas de O y 4 m en la costa noreste de la isla; el más reciente Holoceno y el más antiguo probablemente desarrollado durante el Ultimo Interglacial. Los valores medios de movimientos verticales de los litorales de ambas islas para los últimos 135.000 años, sugieren una ligera tendencia al hundimiento en la isla de Tenerife y un ligero levantamiento en la isla de La Palma
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