Experimental study on solid circulation in a multiple jet fluidized bed

Particle image velocimetry was used to investigate the evolution of multiple inlet gas jets located at the distributor base of a two‐dimensional fluidized bed setup. Results were used to estimate the solid circulation rate of the fluidized bed as well as particle‐entrainment into the individual jets. The effects of fluidization velocity, orifice diameter, orifice pitch, particle diameter, and particle density were studied. It was determined from this study that the solid circulation rate linearly increased with an increase in the fluidization velocity until the multiple jet system transitioned from isolated to an interacting system. In the interacting system of jets, the solid circulation increased with fluidization velocity but at a much lower rate. For multiple jet systems, this phenomenon may indicate the presence of an optimum operating condition with high circulation rate and low air input in the bed. © 2011 American Institute of Chemical Engineers AIChE J, 58: 3003–3015, 2012     

Modulation of physicochemical properties of lipid droplets using β-lactoglobulin and/or lactoferrin interfacial coatings

There is considerable interest in the development of food-grade delivery systems to encapsulate, protect and release bioactive lipids. In this study, emulsion-based delivery systems were prepared consisting of lipid droplets covered by β-lactoglobulin (BLG) and/or lactoferrin (LF) coatings. BLG and LF are globular proteins with relatively low (pI ∼ 5) and high (pI ∼ 8) isoelectric points, respectively. Mixed systems were prepared by adding LF to BLG-stabilized corn oil-in-water emulsions (BLG/LF-coated droplets) or by adding BLG to LF-stabilized corn oil-in-water emulsions (LF/BLG-coated droplets) at pH 7, where there is an electrostatic attraction between the proteins. The influence of pH (3–7), ionic strength (0–60 mM CaCl₂ or 0–200 mM NaCl, pH 7), and thermal treatment (21–90 °C, pH 7, 20 min) on the physical stability of the resulting emulsions was examined. Emulsions with good stability to pH, salt, and thermal processing could be created using mixed interfacial coatings. In addition, we found that the lipids in these emulsions could still be digested using an in vitro digestion model to simulate small intestine conditions. This work may lead to the formation of emulsion-based delivery systems with improved physicochemical and functional performance.     

Bond between deformed reinforcement and normal and high-strength concrete with and without fibers

This paper describes an experimental study that consisted of pullout tests of deformed reinforcing bars in NSC and HSC specimens, with and without hooked-end steel fibers. Two types of test setups were applied, direct and flexural tests, and three bar diameters were tested (8, 12 and 20 mm). The experimental setups were based on standard RILEM pullout (direct) and beam tests, with several modifications. The experimental program included study of the effects of concrete strength and inclusion of steel fibers on the bond strength, as well as the influence of bar geometry and concrete cover. Discussion of the results shows coupling of these effects and proposes an empirical expression that represents this coupling. The results from the current study are also compared with the design bond strengths specified in American and European standards as well as a known model.     

“Andromaly”: a behavioral malware detection framework for android devices

This article presents Andromaly—a framework for detecting malware on Android mobile devices. The proposed framework realizes a Host-based Malware Detection System that continuously monitors various features and events obtained from the mobile device and then applies Machine Learning anomaly detectors to classify the collected data as normal (benign) or abnormal (malicious). Since no malicious applications are yet available for Android, we developed four malicious applications, and evaluated Andromaly’s ability to detect new malware based on samples of known malware. We evaluated several combinations of anomaly detection algorithms, feature selection method and the number of top features in order to find the combination that yields the best performance in detecting new malware on Android. Empirical results suggest that the proposed framework is effective in detecting malware on mobile devices in general and on Android in particular.