Search results for "Redox"
showing 10 items of 619 documents
Electrochemical oxidation of organic pollutants in water at metal oxide electrodes: A simple theoretical model including direct and indirect oxidatio…
2009
Abstract The electrochemical oxidation of organics in water at metal oxide electrodes was investigated with the aim to discuss the correlations between the instantaneous current efficiency ICE and operative conditions by considering both the hypothesis of a direct oxidation process and of an indirect process mediated by adsorbed hydroxyl radicals or chemisorbed “oxygen”, in order to explicit the main differences expected between these cases. Thus, a simple theoretical model was discussed, as an extension of previous studies of Comnnellis and co-workers which were focused on indirect oxidation paths [C. Comninellis, Electrochim. Acta 39 (1994) 1857; O. Simond, V. Schaller, Ch. Comninellis, E…
Electrochemical abatement of chloroethanes in water: Reduction, oxidation and combined processes
2010
An electrochemical route, based on the anodic oxidation to carbon dioxide coupled with the cathodic reduction to de-halogenated hydrocarbons, was proposed for the treatment of waters contaminated by chloroethanes. The electrochemical abatement of two model compounds, namely 1,2-dichloroethane and 1,1,2,2-tetrachloroethane, was carried out by cathodic reduction at silver, anodic oxidation at boron doped diamond (BDD) and combined processes. The anodic oxidation gives rise to a high abatement of the concentration of both these compounds and of COD. The reduction of 1,1,2,2-tetrachloroethane proceeds also with high abatement but with the formation of some halogenated intermediates and final pr…
A crystalline radical cation derived from Thiele’s hydrocarbon with redox range beyond 1 V
2021
Thiele’s hydrocarbon occupies a central role as an open-shell platform for new organic materials, however little is known about its redox behaviour. While recent synthetic approaches involving symmetrical carbene substitution of the CPh2 termini yield isolable neutral/dicationic analogues, the intervening radical cations are much more difficult to isolate, due to narrow compatible redox ranges (typically 1 V), permitting its isolation in crystalline form. Further single-electron oxidation affords borenium dication 12+, thereby establishing an organoboron redox system fully characterized in all three redox states. We perceive that this strategy can be extended to other transient organic rad…
Technical-economical evaluation for distributed storage applications. An Italian case study for a medium-scale public facility
2014
Time-of-use energy cost management involves the use of storage by customers to reduce their electricity bills. This can be accomplished by charging the storage during off-peak time periods, when electricity energy prices are low, and discharging it during times when on-peak energy prices are applied. This article addresses the question whether it is economically viable to install medium-scale distributed storage devices in the power system designed to lower the electricity cost for a customer-side application, assuming flexible electricity tariffs. The technical/economical evaluation is carried out referring to Lithium ion (Li-ion), Sodium Sulphur (NaS) and Vanadium Redox Battery (VRB) tech…
Reverse electrodialysis performed at pilot plant scale: Evaluation of redox processes and simultaneous generation of electric energy and treatment of…
2017
Abstract This paper describes the experimental campaign carried out with a reverse electrodialysis (RED) demonstration plant (Marsala, Italy) with the main aims of: (i) evaluating the effect of various operating parameters, including the redox processes, on the system performances; (ii) using the plant for the simultaneous generation of electric energy and treatment of wastewater. The prototype (44 × 44 cm2, 500 cell pairs) was tested using both real (brackish water and brine) and artificial solutions. Tests with two different electrode rinse solutions (with or without iron redox couples) were performed. In agreement with the data obtained in the laboratory, the presence of iron ions contri…
Are agricultural soils under a continental temperate climate susceptible to episodic reducing conditions and increased leaching of phosphorus?
2012
International audience; Soil science research has probably underestimated the significance that short-term, episodic cycles of reduction and oxidation has had on phosphorus (P) reactivity. Here, the effects of eleven pulsed reduction-oxidation (including wet-dry) cycles on soil P dynamics are compared for 12 soils having contrasting properties and all overfertilised with respect to P. The laboratory based incubation conditions attempted to simulate transient waterlogging of the soil profile and involved repeated sampling and analysis of both the solution and solid phase P forms. An initial increase in P concentration in solution that occurred up to and including the fourth full cycle was fo…
Release of phosphorus under reducing and simulated open drainage conditions from overfertilised soils
2014
Does removal of cations from soil solution during soil reduction stimulate phosphorus (P) release? An ion-exchange resin system was employed to provide a sink during the incubation of twelve soils under fully reducing conditions. This experimental design was considered to better simulate the loss of ions likely to occur under field conditions than more routine batch type closed extraction systems where solutes build-up in the extract solution. The small solute concentrations that remain in the equilibrating solution suggest the mixed resin system acted as an effective sink over the whole experimental period. By maintaining a small P concentration the resin system mimics soil drainage condit…
Liquid-phase alkali-doping of individual carbon nanotube field-effect transistors observed in real-time
2011
The carbon nanotube (CNT) is known to be very sensitive to changes in its surrounding environment. Our study is on the effects of mild, liquid-phase alkali-doping on electronic transport in individual CNTs. We find clear and consistent reversal from p- to n-type behavior, with all seven investigated CNT field-effect transistors (FETs) retaining a similar ON/OFF ratio and subthreshold slope. We have also measured the realtime electronic response during liquid-phase doping, and demonstrate detection of alkali cations with a signal response that ranges over more than three orders of magnitude. The doping is fully reversible upon exposure to oxygen, and the doping cycle is repeatable. We also c…
Microarray mRNA expression analysis of Fanconi anemia fibroblasts.
2007
Fanconi anemia (FA) cells are generally hypersensitive to DNA cross-linking agents, implying that mutations in the different <i>FANC</i> genes cause a similar DNA repair defect(s). By using a customized cDNA microarray chip for DNA repair- and cell cycle-associated genes, we identified three genes, cathepsin B (<i>CTSB</i>), glutaredoxin (<i>GLRX</i>), and polo-like kinase 2 (<i>PLK2</i>), that were misregulated in untreated primary fibroblasts from three unrelated FA-D2 patients, compared to six controls. Quantitative real-time RT PCR was used to validate these results and to study possible molecular links between FA-D2 and other FA subtypes.…
Catalytic oxidation and reduction of polycyclic aromatic hydrocarbons (PAHs) present as mixtures in hydrothermal media
2012
Author's version of an article in the journal: Polycyclic Aromatic Compounds. Also available from the publisher at: http://dx.doi.org/10.1080/10406638.2012.663451 The reactivity of fluorene, anthracene, and fluoranthene under oxidation and reduction conditions were investigated in this study. This project looks at catalytic and green approaches of converting PAHs to less toxic and/or less stable derivatives that are amenable to further degradation. Hydrothermal reactions have been performed at 300°C with pure H2O and Nafion-SiO2 catalyst for oxidation, and pure H2O, HCOOH, Pd-C, and Nafion-SiO2 catalysts for reductive hydrogenation. Time series has been performed for both the oxidation and …