The electrochemical oxidation of para-, meta- and ortho-aminophenols was carried out using a platinum electrode in aqueous acid medium. The spectroscopic results indicate that p-aminophenol suffers hydrolysis giving the formation of hydroquinone/p-benzoquinone.
CO2 has been detected by in situ FTIR…

The Doppler effect is a phenomenon which relates the frequency of the harmonic waves generated by a moving source with the frequency measured by an observer moving with a different velocity from that of the source. The classical Doppler effect…

The theory of α−dense curves in the euclidean space Rn , n ≥ 2, was developed for finding algorithms for Global Optimization of multivariable functions ([1], [6]). The α-dense curves, considered as a generalization of Peano curves or space-filling curves,…

Two ethylene vinyl acetate (EVA) copolymers (12 and 20 wt% of vinyl acetate,VA,
content) have been treated with low pressure RF plasmas from non-oxidizing gases (Ar, N2) and oxidizing gases (air, a mixture of 4N2: 6O2 (v/v), O2 and CO2).…

A procedure to increase the adhesion of block styrene–butadiene–styrene (SBS) rubber consisting of the reactive grafting with maleic anhydride (MA) in the presence of an organic peroxide radical initiator is proposed. The influence of the reactive grafting on the surface…

Molecular data on Lutzomyia are very scarce, despite the fact that this genus includes all the species involved in the transmission of leishmaniasis in America. We examine the genetic relationships among eight morphologic
groups within the Lutzomyia genus and two…

A procedure to determine the best image range of distances that can be obtained from an aphakic eye is presented. Corneal surfaces are calculated from videokeratographic data. Light distributions at different distances inside the eye are calculated with a near-field…

Obtaining holographic volume gratings with high diffraction efficiencies that can be used under white light has been a serious problem for the polyvinyl alcohol-acrylamide-based photopolymers developed by other researchers. In this paper we propose to eliminate the residual monomer in…

Bleached holograms are one of the most interesting techniques used to produce phase holograms of high quality on photographic emulsions. Of particular interest is the method of fixation-free rehalogenating bleaching. Using Kogelnik's coupled-wave theory we shall obtain information about the…

Kogelnik's coupled-wave (CW) theory has been used for decades to predict the diffraction efficiency of volume diffraction gratings. Although this theory has been applied with success to volume diffraction gratings recorded under a great variety of experimental conditions, its predictions…