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In this work we attempt to improve the functional properties and thermal stability of cellulose nanocrystal (CNC) films by means of eco-friendly materials and processes. Mechanically flexible films of closely packed CNCs with concentrations up to 5 wt.% of zinc oxide (ZnO) nanoparticles have been prepared by a simple, standard and environmentally friendly method using solely water. Results reveal that ultraviolet light is blocked by 98.5% at 1 wt.% ZnO while good transparency is maintained. A sharp hydrophobicity increase is observed with the addition of ZnO which would enhance the durability of films by decreasing the water diffusion through the material. The thermal degradation activation energy (E) presents an increase of 141%, denoting a high thermal stability of films, which would result beneficial for their potential application in the field of flexible electronics. Mechanical results demonstrate a high structural integrity of CNC/ZnO as a result of the occurring strong cellulosic inter- and intramolecular interactions within the closely packed CNC network. In overall, this work highlights the potential for environmentally friendly processing of sustainable nanostructured functional materials based on cellulose.

Objetivo: La purificacion del preparado comercial de triamcinolona acetonido disponible es importante para evitar el efecto potencialmente toxico del disolvente alcohol bencilico. Presentamos una nueva tecnica de preparacion de triamcinolona en polvo, a partir de su forma pura, sin disolventes y diluida con agua destilada esteril. Dada su escasa solubilidad en agua se describe como preparar y controlar dicha suspension. Material y metodo: El acetonido de triamcinolona es preparado por el Servicio de Farmacia del Hospital, en condiciones de maxima esterilidad, bajo campana de flujo laminar. La suspension de triamcinolona es envasada en un vial primario, capsulado y posteriormente esterilizado en autoclave a 121 .C. Del vial primario se obtienen dosis individualizadas de 4 mg/0,1 ml. Resultados: Se obtiene la dosis real administrada (3,77 mg/0,1 ml) mediante cuantificacion de triamcinolona por cromatografia liquida de alta resolucion (HPLC). La estabilidad fisica, quimica y microbiologica conservando el vial entre 2-8. se mantiene a los 6 meses. Concusion: Se presenta un metodo de preparacion de triamcinolona en estado puro, obteniendo una concentracion muy proxima a la dosis optima, evitando el uso de disolventes y con maxima garantia de esterilidad

This study was carried out to assess ozone toxicity to 16 populations of Tribolium castaneum (Herbst), 11 populations of Rhyzopertha dominica (F.) and nine populations of Oryzaephilus surinamensis (L.) collected from six regions of Brazil. These populations were also used to test if there is cross-resistance to ozone and phosphine. The relationship between susceptibility to ozone and respiration rate, and associated fitness costs were also evaluated. The instantaneous population growth rate (ri), CO2 production and mean insect body mass of each population were measured. Ozone toxicity was determined using time-response bioassays at the dosage rate of 150 ppm ozone in a continuous flow of 2 L min−1. All of the populations were susceptible to ozone and there was no cross-resistance to ozone and phosphine. The populations of each species differed in respiration rate and body mass, but there was no significant association between respiration rate or body mass and susceptibility to ozone, as was also the case for the instantaneous rate of population increase (ri). As none of the populations showed resistance to ozone, regardless of their susceptibility to phosphine, ozone is a potential alternative for phosphine resistance management in the insect species evaluated in this study.

The present research has been conducted aiming the study of mechanical characteristic improvement of Ti6Al4V alloy surface. The proposed process is based on an ion nitriding method performed in a low intensity plasma jet reactor. An objective of the study is to enlarge the applicability of this alloy in several industrial areas, mainly foccusing the biomedical applications. The reactor of low intensity nitrogen plasma jet is a system governed by principle of gas expansion through a constriction orifice. The whole device is constituted by a plasma source chamber maintained at relatively high pressure and a vacuum chamber where the nitriding is processed, both chambers being separated by a wall having one central orifice. The D.C. electric discharge is run between a cathode located in the source chamber and the wall of the processing chamber playing the role of anode. The reactive plasma jet of nitrogen emerges from the constriction and expands into the vacuum chamber, where the sample is placed to intercept the plasma jet. The nitrided surfaces of Ti6Al4V samples are characterized by means of structural and physical analyses to formulate the correlations between surface characteristics and process parameters.

This article describes the characteristics of the etching process of diamond-like carbon (DLC) films using a new plasma system based on an oxygen plasma jet which comprises charged particles and activated neutral species in a range of energies and fluxes suitable for the etching process. This plasma source was used to etch DLC films which were grown on silicon substrates by magnetron sputtering technique. Prior to etching these films were characterized by different methods, namely Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), current×voltage curves and atomic force microscopy (AFM). Etch rates in the range 7.0–25 nm/min were measured for substrates placed at different positions along the axis of the plasma jet. An attractive feature observed in this work was the influence of an axial magnetic field applied to improve the confinement of the plasma stream. An increase by a factor of 3.4 in the etch rate was verified when the magnetic field increased from 2.5 to 6.0 mT. Raman spectra features (line shapes, frequencies and line width) of the etched films were compared with those obtained before etching. The results show that this plasma jet etching is a reliable technique for DLC film processing.