Carlos F. M. e Silva

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The complex [MoO(2)Cl{HC(3,5-Me(2)pz)(3)}]BF(4) (1) (HC(3,5-Me(2)pz)(3) = tris(3,5-dimethyl-1-pyrazolyl)methane) has been prepared and examined as a catalyst for epoxidation of olefins at 55 °C using tert-butyl hydroperoxide (TBHP) as the oxidant. For reaction of cis-cyclooctene, epoxycyclooctane is obtained quantitatively within 5 h when water is(More)
Fourier transform infrared (FTIR) spectroscopy has being emphasised as a widespread technique in the quick assess of food components. In this work, procyanidins were extracted with methanol and acetone/water from the seeds of white and red grape varieties. A fractionation by graded methanol/chloroform precipitations allowed to obtain 26 samples that were(More)
Device-to-Device (D2D) communications are seen as promising technology for future wireless systems. However, while underlying cellular networks they can negatively affect the performance of cellular communications when intra-cell spectrum sharing is enabled. The impact of D2D communications is not only seen on the cellular throughput, but also on the(More)
Eucalyptus bark contains significant amounts of triterpenoids with demonstrated bioactivity, namely triterpenic acids and their acetyl derivatives (ursolic, betulinic, oleanolic, betulonic, 3-acetylursolic, and 3-acetyloleanolic acids). In this work, the supercritical fluid extraction (SFE) of Eucalyptus globulus deciduous bark was carried out with pure and(More)
Device-to-Device (D2D) communications underlying cellular networks are a way to increase the network capacity and potentially save the battery lifetime of closely located physical devices. However, D2D communications can generate significant interference to the cellular network when the same resources are shared by both systems. Therefore, the design of(More)
The technical feasibility of using stopper-derived cork as an effective biosorbent towards bivalent mercury at environmentally relevant concentrations and conditions was evaluated in this study. Only 25 mg/L of cork powder was able to achieve 94 % of mercury removal for an initial mercury concentration of 500 μg/L. It was found that under the conditions(More)
A counter-current CO 2 fractionation method was applied as a mean to recover n-butanol and other compounds that are typically obtained from biobutanol fermentation broth from aqueous solutions. The influence of operating variables, such as solvent-to-feed ratio, temperature, pressure and feed solution composition was experimentally studied in terms of(More)
Microalgae contain valuable biologically active lipophilic substances such as omega-3 fatty acids and carotenoids. In contrast to the recovery of vegetable oils from seeds, where the extraction with supercritical CO 2 is used as a mild and selective method, economically viable application of this method on similarly soluble oils from microalgae requires, in(More)
In this work it is presented a new model for accurate calculation of binary diffusivities (D12) of solutes infinitely diluted in gas, liquid and supercritical solvents. It is based on a Lennard-Jones (LJ) model, and contains two parameters: the molecular diameter of the solvent and a diffusion activation energy. The model is universal since it is applicable(More)