Lilian L. N. Guarieiro

Use of Patent Indicators as a Methodology for Evaluating the Development of Supercritical Extraction Technology

The use of science and technology indicators that plan investments in research, development and innovation has been growing in recent years. This article aimed to evaluate the scientific and technological indicators, through research related to patent applications and spending on RD&I carried out by the sponsor countries of supercritical extraction technology. Survey was carried out in the online databases for European office Espacenet (EP), by collecting, processing and analysis of information extracted from patent documents. The researched technology is mainly concentrated in developed countries, which have the largest investments in RD&I in recent years.

Prospective Study on the Collection and Incorporation of Cellulose Nanocrystals in Biodegradable Films

In recent years, several research groups have reported new techniques for forming nanocelulose from different natural sources and for the incorporation of these polymeric materials. The objective of this work was to technological prospecting mapping process to obtain nanocrystals, main sources and implementing them in biodegradable films. It was observed that the United States stands out as the largest holder of technology of interest.

Production of biodegradable starch nanocomposites using cellulose nanocrystals extracted from coconut fibers

Different polymeric matrices have been investigated for use in the development of biodegradable films. The incorporation of cellulose nanocrystals in such films has particularly attracted attention because of the potential for achieving improved properties of starch nanocomposites. In the present study, cellulose nanocrystals were extracted from coconut fibers and incorporated in cassava and potato starch films at different concentrations. The properties of the different nanobiocomposite films were comparatively evaluated, including their barrier and mechanical properties. All the films, regardless of the nanocrystal concentration, were found to exhibit low solubility in water, with increased moisture content particularly observed in the films with higher nanocrystal concentrations. The potato starch film with the lowest nanocrystal concentration was found to exhibit the best mechanical properties. The observations of this study indicated that the source of the starch and the nanocrystal concentration determined the properties of the nanobiocomposite films.

Analysis of the GTAW Process Influence on UNS S32760 Superduplex Steel Microstructure and Corrosion Resistance

The use of Superduplex Stainless Steel, on Oil & Gas productive process equipment and piping, meet the requirements of high corrosion resistance, due to their high PREN (Pitting Resistance Equivalent Number), and excellent mechanical properties. However, these steels, because of the high alloy addition, can suffer loss of corrosion resistance and embrittlement when subjected to localized heating. This occurs due to the unbalance of the ferrite a d auste ite phases; for atio of deleterious phases “ig a σ , Chi χ , se o dar auste ite 2 and precipitates of Chromium Nitrides (Cr2N). In this context, the objective of this paper was to analyze the welding process on a UNS S32760 Superduplex steel specimen, subjected to the arc heat of GTAW process. The specimen was produced with the heat input of 1.116J/mm. The samples were analyzed by optical microscopy and scanning electron microscopy (SEM), before and after the corrosion test – according the method A of ASTM G48 Standard. Also, a micro hardiness test was performed to determine the changes on localized mechanical behavior, due to microstructural changes. The study determined: (a) the percentage of each phase present in the sample before process; (b) the Vickers hardness profile after welded; (c) the possible precipitation of deleterious phases, it is associated with de chemical composition of the alloy; (d) the zones and phases preferably attacked on corrosion test; and (e) Pitting morphology.

A Model for Turbulent Diffusion in a Vertically Inhomogeneous Atmospheric Boundary Layer

An analytical solution of the one-dimensional turbulent diffusion equation considering nonFickian closure in a vertically inhomogeneous atmospheric boundary layer (ABL) is presented. The presented solution is improved and more physically consistent in the description of dispersion because it includes (for the first time) the explicit gravitational settling ( s w ) of large particles. Moreover, deposition velocity ( d v ) as a boundary condition, vertical turbulent velocity ( w  ), skewness ( k S ), vertical Lagrangian time ( w L T ) scale and relaxation time ( ) fi ite-velocity diffusio are i cluded. Via numerical simulations, we analyzed the influence of the countergradient term, dry deposition to the ground and gravitational settling on the concentration field. Our results demonstrate an example of the usefulness of analytical solutions to the advection-diffusion equation.An analytical solution of the one-dimensional turbulent diffusion equation considering non-Fickian closure in a vertically inhomogeneous atmospheric boundary layer (ABL) is presented. The presented solution is improved and more physically consistent in the description of dispersion because it includes (for the first time) the explicit gravitational settling ( ) of large particles. Moreover, deposition velocity ( ) as a boundary condition, vertical turbulent velocity ( ), skewness ( ), vertical Lagrangian time ( ) scale and relaxation time ( ) (“finite-velocity” diffusion) are included. Via numerical simulations, we analyzed the influence of the countergradient term, dry deposition to the ground and gravitational settling on the concentration field. Our results demonstrate an example of the usefulness of analytical solutions to the advection-diffusion equation. DOI: 10.5935/1984-6835.20160087