Cinética de adsorción de pigmentos, peróxidos y tocoferoles durante el proceso de blanqueo del aceite de soja

Bleaching is an important process of refining and removes impurities from edible oils. During this process, suspended materials are adsorbed at different adsorption rates, on clay particles. These adsorption rates are important to the design of the process. For this reason, both empirical and theoretical mathematical models were applied in this work in order to predict the adsorption kinetic parameters for tocopherols, peroxides and pigments. The experimental part consisted of mixing neutralized soybean oil with different concentrations of bleaching clays (0.16, 1.0 and 2.0 % w/w) in a laboratory reactor at 96 °C for a 64 min period. Results showed that the theoretical model of first order made better predictions (R2 >0.93) than the empirical models of the kinetic adsorption for tocopherols, peroxides and pigments. The determined kinetic parameters suggest that these bleaching clays presented a high capacity for pigment and peroxide adsorption. The tocopherols were lost as the bleaching clay dosage was increased.El blanqueo es un proceso importante de la refinación para remover impurezas en los aceites comestibles. Durante este proceso, el material suspendido en el aceite se adsorbe sobre las partículas de las tierras de blanqueo a diferentes velocidades, las cuales son importantes para el diseño del proceso. Por esta razón, en este trabajo se aplicaron modelos empíricos y teóricos para predecir los parámetros cinéticos de adsorción de los tocoferoles, peróxidos y pigmentos. La parte experimental consistió en mezclar aceite de soja neutralizado con diferentes concentraciones de tierras de blanqueo (0.16, 1.0 y 2.0 % p/p) en un reactor de laboratorio a 96 °C por 64 minutos. Los resultados mostraron que el modelo teórico de primer orden predice mejor (R2 >0.93) que los modelos empíricos la cinética de adsorción para tocoferoles, peróxidos y pigmentos. Los parámetros cinéticos determinados sugieren que estas tierras presentan una capacidad de adsorción alta para pigmentos y peróxidos. La pérdida de tocoferoles se incremento al aumentar la cantidad de tierra

The Pierre Auger Observatory: Contributions to the 34th International Cosmic Ray Conference (ICRC 2015)

Contributions of the Pierre Auger Collaboration to the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The NetherlandsComment: 24 proceedings, the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands; will appear in PoS(ICRC2015

Arecibo PALFA survey and Einstein@Home: Binary pulsar discovery by volunteer computing

We report the discovery of the 20.7ms binary pulsar J1952+2630, made using the distributed computing project Einstein@Home in Pulsar ALFA survey observations with the Arecibo telescope. Follow-up observations with the Arecibo telescope confirm the binary nature of the system. We obtain a circular orbital solution with an orbital period of 9.4hr, a projected orbital radius of 2.8lt-s, and a mass function of f = 0.15 M ⊙ by analysis of spin period measurements. No evidence of orbital eccentricity is apparent; we set a 2σ upper limit e ≲ 1.7 × 10 -3 . The orbital parameters suggest a massive white dwarf companion with a minimum mass of 0.95 M ⊙ , assuming a pulsar mass of 1.4 M ⊙ . Most likely, this pulsar belongs to the rare class of intermediate-mass binary pulsars. Future timing observations will aim to determine the parameters of this system further, measure relativistic effects, and elucidate the nature of the companion star. © 2011. The American Astronomical Society. All rights reserved