Search results for "ELECTROLYTE"
showing 10 items of 746 documents
Some new polyelectrolytes
1989
Revue de methodes de preparation de polyelectrolytes: alkylation du poly(iminohexamethylene), homo- et copolymeres sequences de l'aza-1 bicyclo [4.2.0] octane, polymeres-peignes prepares a partir de macromeres obtenus par polymerisation de la phenyl-2 oxazoline. Preparation de polyampholytes ayant une distribution statistique ou sequencee des motifs ioniques
Photo-Electrochemical Technologies for Removing Organic Compounds in Wastewater
2018
Abstract In recent years, electrochemical technologies for the prevention and remediation of environmental pollution have been strongly developed. A review of photoelelectrocatalysis (PEC) for the treatment of wastewater is presented in this chapter. Different types of photo-anodes and cathodes have been developed and studied to increase the efficiency of PEC for the removal of organic compounds. An interesting parameter that was investigated in the last work is the generation of an active species by the utilization of proper cathodes. Moreover, this chapter deals with the keys factors affecting the PEC, including electrolyte oxidation.
Laser cleaning of oxidized iron samples: The influence of wavelength and environment
1999
A phenomenological laser-cleaning study of pure oxidized iron samples has been performed in order to model the influence of wavelength in air and the role of environment in the IR domain. Two sets of experiments were performed: (i) cleaning of oxidized specimens at different laser spot sizes and pulse numbers at wavelengths of 1064 nm and 532 nm in air and (ii) cleaning in air with electrolytes at 1064 nm for low energy densities.
Numerical modelling of the electrochemical behaviour of 316 stainless steel based upon static and dynamic experimental microcapillary-based technique…
2008
objective of this work was to determine the parameters that affect the mass transport and the distribution of species in microcapillaries close to the specimen surface. Local experiments were carried out under static and flow conditions on type 316L stainless steel in 1.7 M NaCl, pH = 3, by means of the electrochemical microcell and the scanning droplet cell technique. The polarisation behaviour of pure iron (used as a model system) in an aqueous environment was calculated adopting a finite element approach and was compared to the experimental results. The corrosion system consists of three parallel electrochemical reactions: the oxygen reduction reaction (ORR), the hydrogen evolution react…
A phenomenological approach to the mechanical breakdown of anodic oxide films on zirconium
1986
Abstract A phenomenological theory of the mechanical breakdown of films growing on valve metals during galvanostatic oxidation is presented and discussed in detail for ZrO2 anodic films. It is shown that the mechanical breakdown voltage, Vmb, can be linearly related to the logarithm of the anodizing current density both in the case of constant and variable critical thickness, Lc, at which the breakdown occurs. It is also shown that the Amb and Bmb parameters of the relationship: Vmb = Amb + Bmb log i are strictly related to the kinetic parameters of growth of the films in the different solutions. The expressions of Amb and Bmb parameters are derived for films grown in the presence as well a…
Gelled Electrolyte Containing Phosphonium Ionic Liquids for Lithium-Ion Batteries
2018
In this work, new gelled electrolytes were prepared based on a mixture containing phosphonium ionic liquid (IL) composed of trihexyl(tetradecyl)phosphonium cation combined with bis(trifluoromethane)sulfonimide [TFSI] counter anions and lithium salt, confined in a host network made from an epoxy prepolymer and amine hardener. We have demonstrated that the addition of electrolyte plays a key role on the kinetics of polymerization but also on the final properties of epoxy networks, especially thermal, thermo-mechanical, transport, and electrochemical properties. Thus, polymer electrolytes with excellent thermal stability (>
Towards enhanced durability of electrochromic WO3 interfaced with liquid or ceramic sodium-based electrolytes
2020
Abstract The reversible intercalation of sodium ion into tungsten oxide WO3 appears as an interesting alternative to hydrogen or lithium ion reduction in order to get the characteristic transition from clear transparent to bluish coloration in electrochromic devices, but it has been comparatively less considered. In order to address further viable all-ceramic devices based on sodium ion intercalation and overcome the issue of WO3 degradation in aqueous media, three configurations of WO3 thin film-based electrochromic half-cells were tested, namely in (i) aqueous acidified Na2SO4 electrolyte, (ii) room temperature ionic liquid BEPipTFSI electrolyte and (iii) aqueous acidified Na2SO4 electrol…
Acid−Base Properties of Synthetic and Natural Polyelectrolytes: Experimental Results and Models for the Dependence on Different Aqueous Media
2008
Protonation constants of several natural and synthetic humates and fulvates were determined by ISE-H+ potentiometry in different ionic media (alkali metal halides and tetraethylammonium iodide) at different ionic strengths and T ) 298.15 K. Experimental data obtained in previous studies of different synthetic (polyacrylates, polymethacrylates, polyacrylate-co-maleate) and naturally occurring (alginate, humic substances) polycarboxylates were also taken into account in the general analysis of acid-base properties of polyelectrolytes. Protonation constants were expressed as a function of the dissociation degree (R) using three models, namely, a simple linear model, the Ho¨gfeldt three-paramet…
Enantiodifferentiation of N-benzyloxycarbonylaminophosphonic and phosphinic acids and their esters using cyclodextrins by means of capillary electrop…
2005
Capillary electrophoresis was successfully applied for separation of the enantiomers of N-benzyloxycarbonyl-alpha-aminophosphonic and alpha-aminophosphinic acids as well as their ethyl and phenyl monoesters with the use of a range of commercially available cyclodextrins (alpha, beta and hydroxypropyl-gamma-cyclodextrins) as chiral selectors. The dependence of effectiveness of separation on type and concentration of these chiral selectors as well as on pH of background electrolyte was examined in some detail.
Separation of aminoalkanephosphonic acid enantiomers by indirect UV detection capillary electrophoresis with application of cyclodextrins.
2003
Indirect UV detection capillary electrophoresis (CE) was used for the separation of aminoalkanephosphonic acid (AP) enantiomers by applying commercially available cyclodextrins as chiral discriminators. The results show that the separation of the enantiomers depends on pH of the background electrolyte, the molar ratio of cyclodextrin to aminophosphonic acid, and on the type of the applied chiral selector. Optimization of process conditions allowed enantiomeric baseline separation or partial separation of 12 out of 14 alpha-aminophosphonic acids studied. This type of CE might therefore be successfully used for routine determination of enantiomeric purity of aminophosphonic acids.