Gaining further insight into photo-Fenton treatment of phenolic compounds commonly found in food processing industry

A mixture of eight phenolic compounds, namely 2,4-dinitrophenol, tannic, ellagic, gallic, protocatechuic, vanillic, syringic and sinapic acids, have been treated by means of a photo-Fenton process under simulated and real sunlight. An experimental design methodology, based in Doehlert matrixes, was employed to check the effect of the concentration of Fe(II) and H2O2, as well as pH. Response surfaces show that photo-Fenton can be extended to pH values clearly above 2.8, probably due to complexation of iron with the phenolic substances. Experiments performed under solar irradiation at pH = 3.9 showed that complete removal of the monitored pollutants was achieved in less than 3 min; mineralisation was also efficient, although some organics remained in the solution. Toxicity was monitored according to Pseudokirchneriella subcapitata and Daphnia magna bioassays; Recombinant Yeast Assay (RYA) was employed to assess estrogenic and dioxin-like activities. 2,4-Dinitrophenol was demonstrated to be the major concern and, in general, photo-Fenton resulted in a detoxification of the solution. Finally, excitation emission matrix (EEM) fluorimetry was employed to obtain complementary information on the behaviour of organic matter. Most peaks associated with the parent pollutants disappeared after short irradiation periods and, at 12 min of irradiation chromophores were destroyed, what can be associated with the removal of complex molecules. (C) 2015 Elsevier B.V. All rights reserved.The authors want to thank the financial support of the Spanish Ministerio de Education y Ciencia (CTQ2012-38754-C03-02) and Generalitat Valenciana (GV/2015/074). Sara Garcia-Ballesteros would like to thank Spanish Ministerio de Economia y Competitividad for her fellowship (BES-2013-066201).García Ballesteros, S.; Mora Carbonell, M.; Vicente Candela, R.; Sabater Marco, C.; Castillo López, MÁ.; Arques Sanz, A.; Amat Payá, AM. (2016). Gaining further insight into photo-Fenton treatment of phenolic compounds commonly found in food processing industry. Chemical Engineering Journal. 288:126-136. https://doi.org/10.1016/j.cej.2015.11.031S12613628

Early life differences in behavioral predispositions in two Alligatoridae species

Behavioral predispositions are innate tendencies of animals to behave in a given way without the input of learning. They increase survival chances and, due to environmental and ecological challenges, may vary substantially even between closely related taxa. These diferences are likely to be especially pronounced in long-lived species like crocodilians. This order is particularly relevant for comparative cognition due to its phylogenetic proximity to birds. Here we compared early life behavioral predispositions in two Alligatoridae species. We exposed American alligator and spectacled caiman hatchlings to three different novel situations: a novel object, a novel environment that was open and a novel environment with a shelter. This was then repeated a week later. During exposure to the novel environments, alligators moved around more and explored a larger range of the arena than the caimans. When exposed to the novel object, the alligators reduced the mean distance to the novel object in the second phase, while the caimans further increased it, indicating diametrically opposite ontogenetic development in behavioral predispositions. Although all crocodilian hatchlings face comparable challenges, e.g., high predation pressure, the effectiveness of parental protection might explain the observed pattern. American alligators are apex predators capable of protecting their offspring against most dangers, whereas adult spectacled caimans are frequently predated themselves. Their distancing behavior might be related to increased predator avoidance and also explain the success of invasive spectacled caimans in the natural habitats of other crocodilians

Compensation for geometric modeling errors by positioning of electrodes in electrical impedance tomography

Electrical impedance tomography aims at reconstructing the conductivity inside a physical body from boundary measurements of current and voltage at a finite number of contact electrodes. In many practical applications, the shape of the imaged object is subject to considerable uncertainties that render reconstructing the internal conductivity impossible if they are not taken into account. This work numerically demonstrates that one can compensate for inaccurate modeling of the object boundary in two spatial dimensions by finding compatible locations and sizes for the electrodes as a part of a reconstruction algorithm. The numerical studies, which are based on both simulated and experimental data, are complemented by proving that the employed complete electrode model is approximately conformally invariant, which suggests that the obtained reconstructions in mismodeled domains reflect conformal images of the true targets. The numerical experiments also confirm that a similar approach does not, in general, lead to a functional algorithm in three dimensions.Peer reviewe