SNIPPET ON DRYING

ABSTRACT

When regarding the atmospheric contact drying of granular beds wetted with a liquid mixture, both the drying rate and the selectivity of the process, i.e. the change of moisture composition, are of interest. The batch drying of a free flowing ceramic substance, wetted with a 2-propanol-water mixture, is investigated in a rotary dryer with heated wall and air flow.

The theoretical analysis is based on physical models for heat and mass transfer, moisture migration and particle transport, which are presented in examples.

The experimental and theoretical results show that higher selectivities can be achieved by reducing the particle size because of the lower liquid-phase mass-transfer resistance. An increase of the rotational speed leads to a higher drying rate with slightly decreased selectivity if the particles are sufficiently small, since contact heat transfer is enhanced.     

Continuous blending of cohesive granular material

Results are presented from discrete element method (DEM) computer simulations of cohesive particles in a periodic slice of a continuous blender. The influence of inter-particle cohesion at various impeller speeds and fill levels is reported. Although increasing cohesion does not significantly change axial flow rates, mixing rates in the transverse plane and axial direction are affected. Mixing is generally enhanced for slightly cohesive materials, but decreases for larger cohesion, similar to trends observed in tumbling batch mixers. Changes in fill level are also shown to affect axial transport rates and mixing. These results suggest that the controllable operating parameters, such as feed rate and impeller speed, may be adjusted for cohesive powder formulations to obtain optimal mixing performance.     

Eye tracking as an MT evaluation technique

Eye tracking has been used successfully as a technique for measuring cognitive load in reading, psycholinguistics, writing, language acquisition etc. for some time now. Its application as a technique for measuring the reading ease of MT output has not yet, to our knowledge, been tested. We report here on a preliminary study testing the use and validity of an eye tracking methodology as a means of semi-automatically evaluating machine translation output. 50 French machine translated sentences, 25 rated as excellent and 25 rated as poor in an earlier human evaluation, were selected. Ten native speakers of French were instructed to read the MT sentences for comprehensibility. Their eye gaze data were recorded non-invasively using a Tobii 1750 eye tracker. The average gaze time and fixation count were found to be higher for the “bad” sentences, while average fixation duration and pupil dilations were not found to be substantially different for output rated as good and output rated as bad. Comparisons between HTER scores and eye gaze data were also found to correlate well with gaze time and fixation count, but not with pupil dilation and fixation duration. We conclude that the eye tracking data, in particular gaze time and fixation count, correlate reasonably well with human evaluation of MT output but fixation duration and pupil dilation may be less reliable indicators of reading difficulty for MT output. We also conclude that eye tracking has promise as a semi-automatic MT evaluation technique, which does not require bi-lingual knowledge, and which can potentially tap into the end users’ experience of machine translation output.     

Effect of taro (Colocasia esculenta) flour addition on the functional and alveographic properties of wheat flour and dough

BACKGROUND: Taro is a plant widely produced in tropical areas for its underground corms. Taro corms are highly perishable owing to their high moisture content. In order to limit post‐harvest losses and improve the production and consumption, production and utilization of taro flour have been envisaged. In connection with this, the incorporation of taro flour into wheat‐based products has been reported to increase their keeping quality. Before consideration is given to taro flour as a substitute for wheat in bread manufacture, it is necessary to characterize the functionality of the composite flour and dough. The present study investigated the physicochemical and alveographic properties of wheat–taro composite flour. RESULTS: Three varieties of taro flour (WCN, RIN and KWN) were incorporated into wheat flour in proportions of 10%, 20% and 30% (w/w) and the water absorption capacity (WAC), retrogradation index (RI), foam capacity (FC) and other functional properties were measured. In addition, characteristics of dough rupture pressure (P), extensibility (L), elasticity index (Ie) and strength (W) of flour made from the different composites were measured using an alveograph. The results showed that WAC significantly increased from 132% (wheat flour) to 156% (30% composite flour), while RI significantly decreased from 38% to a mean value of 22%. Principal component analysis revealed that WAC and P formed a group of variables negatively correlated with a second group made of RI, FC, W, Ie and L. CONCLUSION: Incorporating taro flour up to a level of 10% had no significant effect on the functional and alveographic properties of the flours. This suggested that in order to guarantee the quality of bread made from wheat–taro composite the level of taro addition should not exceed 10%. Copyright © 2007 Society of Chemical Industry     

A longitudinal investigation of anxiety sensitivity in adolescence.

This investigation sought to expand existing knowledge of anxiety sensitivity in a sample of high school students (N = 2,365) assessed over 4 years. The stability of anxiety sensitivity levels across assessment periods was examined, and cluster analyses were used to identify different developmental pathways in levels of anxiety sensitivity. Groups of adolescents with stable low, stable high, and escalating anxiety sensitivity levels were identified. Adolescents with stable high or escalating anxiety sensitivity were significantly more likely to report experiencing a panic attack than individuals with stable low anxiety sensitivity. Results also indicated that Asian and Hispanic adolescents tended to report higher anxiety sensitivity but that their anxiety sensitivity was less strongly associated with panic than that of Caucasian adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phase Relationships and Physical Properties of Homologous Compounds in the Zinc Oxide-Indium Oxide System

Equilibrium phase relationships in the ZnO-In₂O₃ system were determined between 1100° and 1400°C using solid-state reaction techniques and X-ray diffractometry. In addition to ZnO and In₂O₃, nine homologous compounds, Zn _k In₂O _{k +3} (where k = 3, 4, 5, 6, 7, 9, 11, 13, and 15), were observed. Electrical conductivity and diffuse reflectance of the k = 3, 4, 5, 7 and 11 members were measured before and after annealing at 400°C for 1 h under forming gas (4%₂-96% N₂). Room-temperature conductivity increased as k decreased, because of increased carrier concentration as well as increased mobility. In general, transparency in the wavelength range of 450-900 nm increased as k increased. Reduction in forming gas resulted in increased conductivity and reduced transparency for all compounds measured. The highest room-temperature conductivity measured, 270 S/cm, was that of reduced Zn₃In₂O₆.