Search results for "Anode"
showing 10 items of 317 documents
Using Matlab's wavelet toolbox to compare electric signals outputted by microbial fuel cells
2019
Motivation: microbial fuel cells (MFC) represents a wastewater treatment technology with the potential for a relevant electric energy generation. The monitoring of the electric current outputted generates time series of data. It was generated two time series using an experimental setup with a low-cost dual chamber microbial fuel cell treating cassava wastewater and, also, it was used the electric current data from a previously described experiment with this same setup treating cheese whey. All of this, innovatively, according our best knowledge, was studied using power spectral density, multifractal and wavelet coherence analysis. Results are promising and indeed point out this approach as …
A single-chamber membraneless microbial fuel cell exposed to air using Shewanella putrefaciens
2016
Abstract Microbial Fuel Cells (MFCs) are bio-electrochemical devices which convert the chemical energy content of organic fuels into electricity, thanks to the ability of anode respiring bacteria to give electrons to the anode. This result is usually achieved under anaerobic conditions, obtained with a sealed anode chamber. Despite this, Shewanella oneidensis has been recognized by many authors to obtain the same results in presence of air. Furthermore, another member of the Pseudomonaceae family, Shewanella putrefaciens, has also shown the capability to catalyze the cathodic oxygen reduction. In this work the capability of S. putrefaciens to work under both anaerobic and micro-aerobic cond…
Information entropy-based classification of triterpenoids and steroids from Ganoderma
2015
Abstract A set of 71 triterpenoid and steroid compounds from Ganoderma were periodically classified using a procedure based on information entropy with artificial intelligence. Six features were used in hierarchical order to classify the triterpenoids and steroids structurally. The phytochemicals belonging to the same group in the periodic table present similar antioxidant activity, and those compounds belonging to the same period exhibit maximum resemblance. The periodic classification is related to the experimental bioactivity and antioxidant potency data that are available in the literature: a steroid with a three-ketone group conjugated with two carbon–carbon double bonds in the right s…
Nano-demixing as a novel strategy for magnetic field responsive systems: the case of dibutyl phosphate/bis(2-ethylhexyl)amine systems
2016
Pure surfactant liquids and their binary mixtures, owing to the amphiphilic nature of the molecules involved, can exhibit nano-segregation and peculiar transport properties. The possibility of opportunely choosing the amphiphiles should lead to the formation of anisotropic aggregates that can be oriented by an external factor like a magnetic field. In this case some properties, like optical birefringence, can be induced by the use of a magnetic field. Dynamic features of dibutyl phosphate (DBP)/bis(2-ethylhexyl)amine (BEEA) mixtures have been investigated by FT-IR, NMR, rheometry, Brillouin scattering, and magnetically-induced birefringence measurements as a function of the BEEA mole fracti…
Nanowires for NEMS Switches
2020
Nanoelectromechanical systems (NEMS) are a promising novel technology for operation in extreme conditions (e.g. high temperature and radiation levels), where complementary semiconductor technology devices might fail due to electronic instability. An example for a NEMS device is a nanowire-based switch, which employs mechanical deflection of a nanowire to open and close an electrical circuit. To date, assembly and operation of individual nanowire based NEMS switches have been successfully demonstrated at laboratory level, but their further technological development remains a challenge. This chapter gives an insight into the current advances in applications of nanowires for NEMS switches. Syn…
Influence of annealing conditions on the photoelectrocatalytic performance of WO3 nanostructures
2020
[EN] Nanostructured WO3 photoanodes have been synthesized by electrochemical anodization under controlled hydrodynamic conditions in acidic media in the presence of 0.05 M H2O2. Subsequently, samples have been subjected to a thermal treatment (annealing) at different temperatures (400 degrees C, 500 degrees C and 600 degrees C) and under different gaseous atmospheres (air, N-2, Ar). The influence of these annealing conditions on the morphology, crystallinity, photoelectrochemical behavior and dopant chemistry of the different photoanodes has been investigated through Electronic Microscopy, Raman Spectroscopy, Photoelectrochemical Impedance Spectroscopy and Mott-Schottky analysis. In general…
Influence of electrodeposition techniques on Ni nanostructures
2008
Abstract Different Ni nanostructure arrays were fabricated by pulsed electrodeposition from a Watts bath inside the pores of anodic alumina membrane (AAM) templates. Under a trapezoidal waveform of potential, consisting of fast linear sweeps between 0 and −3 V (SCE) interleaved by delay times at 0 (10 s) and −3 V (0.1 s), Ni nanowires were grown. The rate of nanowires growth was constant up to 60 min of deposition. For longer times, the growth of nanowires was not uniform, and after about 180 min some nanowires reached the template surface exposed to the electrolyte. Under square potential pulses between the same potentials (pulse length 1 s), nanotubes of Ni are obtained. Morphological ana…
Quartz Crystal Microbalance And Electrical Impedance Characterization Of Nickel Dissolution Process.
2005
Abstract. The anodic nickel dissolution in acid media is analysed by means of EQCM and EIS techniques. The experimental impedance spectra have been fitted to the equivalent circuit which corresponds to two consecutive electron transfers followed by a Ni(II) desorption. That way rate constants and surface concentrations of the Ni(0) and Ni(I) species are obtained. EQCM also provides information about the mechanism of deposition and passivation of nickel as well as the hydrogen evolution.
Electric field manipulation in Al/CdTe/Pt detectors under optical perturbations
2017
Abstract Al/CdTe/Pt detectors are very attractive devices for high-resolution X-ray spectroscopy, even though they suffer from polarization phenomena, which cause a progressive time degradation of the spectroscopic performance. In this work we investigated on the time dependence of the electric field of an Al/CdTe/Pt detector under optical perturbation by means of Pockels effect measurements. A tunable laser with wavelengths ranging within 700−1000 nm and a 940 nm light emitting diode (LED) were used. The measurements of both the electric field profile and the total current were used to better understand the effects of the optical perturbation on polarization phenomena. The results point ou…
Multi-technique characterization of gold electroplating on silver substrates for cultural heritage applications
2017
Proceedings of the 12th European Conference on Accelerators in Applied Research and Technology (ECAART12).-- et al.