215 research outputs found

    Electrochemical remediation of phenol contaminated kaolin under low-strength electric fields

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    Soil degradation is a global concern. Electrochemical remediation (ER) technology is considered an appealing strategy for soil remediation because it is a low-cost, adaptable, and effective noninvasive in situ technology. Currently, the remediation of soil characterized by fine grains, low-hydraulic permeability, heterogeneous conditions, and mixtures of contaminants is still challenging since other conventional technologies are poorly effective. ER of soil is based on the application of low potentials between a couple of electrodes which induces an electric field (E) in the contaminated field. In this work, very low values of electric field (E ≤ 0.25 V cm−1) were used for the ER of contaminated kaolin. Phenol was selected as model hazardous organic compound and kaolin as model, reproducible and low buffering and low permeability clay. The effect of several factors, including the nature of the electrodes, treatment time, kind of current, the strength of the E and the nature of supporting electrolyte, on the performance of the process was investigated in detail and discussed in terms of the normalized phenol concentration and its total removal from the kaolin. Overall, the main finding is that the use of very low value of E (0.15 V cm−1) can allow to simultaneously desorb, mobilize and also in-situ degrade phenol. The highest removals of phenol up to approximately 80% and 90% from the kaolin under both direct and sinusoidal E, respectively, were reached using compact graphite as electrodes in presence of Na2SO4 into the kaolin

    Electrochemical remediation of kaolin-soil contaminated by phenol: effect of several operative parameters

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    Electrochemical remediation technology is considered an appealing strategy for the remediation of fine- grained soils, characterized by a low hydraulic conductivity and large specific surface area, contaminated with inorganic, organic, and mixed pollutants. In both Electrokinetic (EK) and Electrochemical Geo-Oxidation (ECGO) technologies, an electric field is imposed on the contaminated soil to remove the pollutants by the combined mechanisms of electroosmosis, electromigration, and/or electrophoresis. Moreover, ECGO uses low voltage and both direct and alternating amperage (DC/AC) applied in a proprietary series to induce reduction-oxidation reactions on soil surfaces at the micro-scale. According to the literature, in this method, each soil particle acts as a micro-capacitor that charges and discharges in a cyclic fashion. The energy burst on discharge at the micro-scale is intense, theoretically allowing the conversion of most organic contaminants to carbon dioxide and water near the conducting particle surface [2-4]. However, the effectiveness of the technology strongly depends on the physical-chemical states of the soils and the contaminants, pH, sorption of contaminants on soil particle surfaces and different effects induced by the hydrogen ions and hydroxide ions generated at the electrodes. In this work, the effect of several factors, including the intensity and mode of the applied electric field, duration of treatment, nature of supporting electrolytes, on the electrochemical remediation of kaolin-soil contaminated by phenol (200 mgPhenol/kgsoil) was investigated. It was found that a proper selection of the operative parameters is the key- factor to improve the electrochemical remediation of the contaminated soil. High removal of phenol from the kaolin up to 88% was achieved after 93 hours of treatment using graphite electrodes and a gradient electric field of 0.15 V cm-1. [1] A. T. Yeung et al. J. Hazard. Mater. 2011, 195, 11 [2] D. Rahner et al. Electrochim. Acta 2002, 47, 1395 [3] J. Röhrs et al. Electrochim. Acta 2002, 47, 1405 [4] L.M. Zanko et al. Electrochim. Acta 2020, 354, 13669

    A crystalline incarnation of Berthelot's conjecture and Künneth formula for isocrystals

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    This is the author accepted manuscript. The final version is available from the American Mathematical Society via the DOI in this recordBerthelot’s conjecture predicts that under a proper and smooth morphism of schemes in characteristic p, the higher direct images of an overconvergent F-isocrystal are overconvergent F-isocrystals. In this paper we prove that this is true for crystals up to isogeny. As an application we prove the Künneth formula for the crystalline fundamental group scheme.European Research Council (ERC)Einstein Foundatio

    Effect of the air pressure on electro-Fenton process

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    Electro-Fenton process is considered a very promising tool for the treatment of waste waters contaminated by organic pollutants refractant or toxic for microorganisms used in biological processes [1-6]. In these processes H2O2 is continuously supplied to an acidic aqueous solution contained in an electrolytic cell from the two-electron reduction of oxygen gas, directly injected as pure gas or bubbled air. Due to the poor solubility of O2 in aqueous solutions, two dimensional cheap graphite or carbon felt electrodes give quite slow generation of H2O2, thus resulting in a slow abatement of organics. In this context, we report here a series of studies [7-9] on the effect of air pressure on the electro-generation of H2O2 and the abatement of organic pollutants in water by electro-Fenton process. The effect of air pressure, current density, mixing and nature of the organic pollutant was evaluated. [1] E. Brillas, I. Sirés, M.A. Oturan, Chem. Rev., 109 (2009) 6570-6631. [2] C.A. Martínez-Huitle, M.A. Rodrigo, I. Sirés, O. Scialdone, Chem. Rev. 115 (2015) 13362–13407. [3] M. Panizza, G. Cerisola, Chem. Rev. 109 (2009) 6541–6569. [4] I. Sirés, E. Brillas, M.A. Oturan, M.A. Rodrigo, M. Panizza, Environ. Sci. Pollut. Res. 21 (2014) 8336–8367. [5] C.A. Martínez-Huitle, S. Ferro, Chem. Soc. Rev. 35 (2006) 1324–1340. [6] B.P.P. Chaplin, Environ. Sci. Process. Impacts. 16 (2014) 1182–1203. [7] O. Scialdone, A. Galia, C. Gattuso, S. Sabatino, B. Schiavo, Electrochim. Acta, 182 (2015) 775-780. [8] J.F. Pérez, A. Galia, M.A. Rodrigo, J. Llanos, S. Sabatino, C. Sáez, B. Schiavo, O. Scialdone, Electrochim. Acta, 248 (2017) 169-177. [9] A.H. Ltaïef, S. Sabatino, F. Proietto, A. Galia, O. Scialdone, O. 2018, Chemosphere, 202, 111-118

    Behavior of a forest of NiFe nanowires in KOH and NaCl solution for water electrolysis

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    The present work investigates the behavior of nanostructured electrodes consisting of an array of nanowires of NiFe alloy in KOH + 0.5 M NaCl solution. The aim is to explore the possibility of using these electrodes for hydrogen production by seawater electrolysis. Seawater splitting requires a highly selective electrode on the anode side, where the evolution of molecular chlorine or the formation of other active chlorine compounds can compete with the oxygen evolution reaction. Nanostructured electrodes, obtained by template electrosynthesis, were tested at room temperature in KOH + 0.5 M NaCl solution, and the results were compared with those obtained in pure KOH. The results showed that the presence of NaCl does not affect the electrocatalytic behavior of the nanostructured NiFe alloy. Furthermore, the chemical–physical characterizations carried out after the long-term galvanostatic tests, have shown that the nanostructured electrodes are also stable in terms of morphology and composition. In addition, the solution used to perform the long-term galvanostatic tests was analyzed to investigate the possible formation of chlorine compounds. The absence of these compounds, together with the measured potential value measured for the oxygen evolution reaction, which was always lower than the thermodynamic redox potential for the hypochlorite formation reaction, leads us to conclude that these electrodes are potentially suitable for seawater electrolysis

    Detection of EGFR-Activating and T790M Mutations Using Liquid Biopsy in Patients With EGFR-Mutated Non–Small-Cell Lung Cancer Whose Disease Has Progressed During Treatment With First- and Second-Generation Tyrosine Kinase Inhibitors: A Multicenter Real-Life Retrospective Study

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    Epidermal growth factor receptor T790M detection using liquid biopsy was evaluated in a real-life setting in 120 advanced non–small-cell lung cancer patients whose disease had progressed during first- or second-generation tyrosine kinase inhibitors. The T790M detection rate was 25.8% using liquid biopsy and 49.2% after tissue rebiopsy. Liquid biopsies performed before disease progression according to Response Evaluation Criteria In Solid Tumors were all negative for T790M and T790M positivity was higher in cases of extrathoracic metastatic sites

    Better Knee, Better Me™: effectiveness of two scalable health care interventions supporting self-management for knee osteoarthritis – protocol for a randomized controlled trial

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    Although education, exercise, and weight loss are recommended for management of knee osteoarthritis, the additional benefits of incorporating weight loss strategies into exercise interventions have not been well investigated. The aim of this study is to compare, in a private health insurance setting, the clinical- and cost-effectiveness of a remotely-delivered, evidence- and theory-informed, behaviour change intervention targeting exercise and self-management (Exercise intervention), with the same intervention plus active weight management (Exercise plus weight management intervention), and with an information-only control group for people with knee osteoarthritis who are overweight or obese

    Toll-Like Receptor (TLR) and Nucleosome-binding Oligomerization Domain (NOD) gene polymorphisms and endometrial cancer risk

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    Background: Endometrial cancer is the most common gynaecological malignancy in women of developed countries. Many risk factors implicated in endometrial cancer trigger inflammatory events; therefore, alterations in immune response may predispose an individual to disease. Toll-like receptors (TLRs) and nucleosome-binding oligomerization domain (NOD) genes are integral to the recognition of pathogens and are highly polymorphic. For these reasons, the aim of the study was to assess the frequency of polymorphic variants in TLR and NOD genes in an Australian endometrial cancer population. Methods: Ten polymorphisms were genotyped in 191 endometrial cancer cases and 291 controls using real-time PCR: NOD1 (rs2075822, rs2907749, rs2907748), NOD2 (rs5743260, rs2066844, rs2066845), TLR2 (rs5743708), TLR4 (rs4986790) and TLR9 (rs5743836, rs187084). Results: Haplotype analysis revealed that the combination of the variant alleles of the two TLR9 polymorphisms, rs5743836 and rs187084, were protective for endometrial cancer risk: OR 0.11, 95% CI (0.03-0.44), p = 0.002. This result remained highly significant after adjustment for endometrial cancer risk factors and Bonferroni correction for multiple testing. There were no other associations observed for the other polymorphisms in TLR2, TLR4, NOD1 and NOD2. Conclusions: The variant 'C' allele of rs5743836 causes greater TLR9 transcriptional activity compared to the 'T' allele, therefore, higher TLR9 activity may be related to efficient removal of microbial pathogens within the endometrium. Clearly, the association of these TLR9 polymorphisms and endometrial cancer risk must be further examined in an independent population. The results point toward the importance of examining immune response in endometrial tumourgenesis to understand new pathways that may be implicated in disease
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