Study of dynamic viscoelastic behavior of polystyrene films on addition of oleic acid

We have investigated the dynamic mechanical behavior of films prepared from polystyrene solutions in chloroform containing oleic acid as an additive. The response of the films has been measured by means of a dynamic mechanical analyzer operated in tension mode over a temperature range of 30-150 °C, using sinusoidal motion with a maximum strain of 0.04% and a frequency of 2 Hz. The long term creep behavior has also been evaluated. Our results show that the oleic acid softens and disentangles the polystyrene chains backbone, resulting in a decrease in the dynamic mechanical properties of the polystyrene films.     

Structural study of Zr doped PbTiO3 materials by employing Rietveld method

Single phase materials of PbZr_1?xTi_xO₃ (x = 1.00, 0.65 and 0.35) were prepared by following the solid state route. All the materials were prepared in nanocrystalline form as well as microcrystalline form. Evolution of crystallization was studied by characterizing the samples annealed at different temperatures. XRD patterns were analyzed with the help of Fullprof program by employing Rietveld refinement technique. The patterns for x = 1.00 and 0.65 could be refined using P4mm space group in tetragonal symmetry. However, the samples for x = 0.35 could be refined using R3c space group in rhombohedral symmetry. It has been found that crystallite size increases with the annealing temperature for all the samples. The scanning electron microscope (SEM) and energy dispersive X-ray spectroscope (EDS) analysis reveals that the materials are uniform and their composition is as per the chemical formulae. All the samples exhibit ferroelectric to paraelectric transition.     

Observation of Crack Propagation in Glass Using X-ray Phase Contrast Imaging

High-speed X-ray phase contrast imaging synchronized with a Kolsky bar apparatus was utilized to investigate the cracking behavior of a borosilicate glass, a soda lime glass, and a glass ceramic in front of a cylindrical projectile with an impact velocity of 5 ms⁻¹. For each material, three different surface conditions were prepared for the impacted edge of the specimen. Angular cracking was observed in front of the projectile for borosilicate glass. For soda lime glass, straight cracking was observed. For glass ceramic, curved cracking was observed in front of the projectile. Cracking behavior was observed to be independent of the surface condition on the impacted edge.     

Decolourization of Methyl Orange using Fenton-like mesoporous Fe(2)O(3)-SiO(2) composite

Rapid decolourization of Methyl Orange by Fenton-like mesoporous Fe(2)O(3)-SiO(2) catalyst has been reported. The effect of various parameters such as initial pH, initial H(2)O(2) concentration, Fe content in the catalyst and initial dye concentration on decolourization process were studied. The results show that 20mg of mesoporous Fe(2)O(3)/SiO(2) composite (with Si/Fe=10) was sufficient to decolourize 0.6 mg/ml of Methyl Orange in presence of 2 ml of H(2)O(2) at an initial pH of 2.93 within 20 min. The pH range for effective decolourization (≥90%) was found to be 1-3. Leaching tests indicated that the activity of the catalyst was almost unaffected up to three consecutive cycles although ≤0.2 ppm of Fe ion was leached into treated water in each run.     

A unified paradigm for scalable multi-projector displays

We present a general framework for the modeling and optimization of scalable multi-projector displays. Based on this framework, we derive algorithms that can robustly optimize the visual quality of an arbitrary combination of projectors without manual adjustment. When the projectors are tiled, we show that our framework automatically produces blending maps that outperform state-of-the-art projector blending methods. When all the projectors are superimposed, the framework can produce high-resolution images beyond the Nyquist resolution limits of component projectors. When a combination of tiled and superimposed projectors are deployed, the same framework harnesses the best features of both tiled and superimposed multi-projector projection paradigms. The framework creates for the first time a new unified paradigm that is agnostic to a particular configuration of projectors yet robustly optimizes for the brightness, contrast, and resolution of that configuration. In addition, we demonstrate that our algorithms support high resolution video at real-time interactive frame rates achieved on commodity graphics platforms. This work allows for inexpensive, compelling, flexible, and robust large scale visualization systems to be built and deployed very efficiently.     

Mass Transfer During Sucrose Infusion into Potatoes under High Pressure

ABSTRACT: The diffusion coefficient of sucrose in potato cylinders was determinted at the various pressures (200 to 600 MPa) and temperatures (20, 40, and 60 °C). Application of pressure opened up the tissue structure and facilitated diffusion. However, higher pressures above 400 MPa also induced starch gelatinization and hindered diffusion. The maximum diffusion coefficient was therefore, dependent on which of the 2 effects dominated. In this study, the maximum value of diffusion coefficient observed represented an 8-fold increase over ambient values. Thus, application of appropriate levels of pressure (100 to 400 MPa), can be used to accelerate mass transfer during ingredient infusion into foods.     

Enzyme‐assisted water‐extraction of oil and protein from rice bran

Enzymatic water‐extraction of oil and proteins from rice bran was studied in a laboratory‐scale set‐up. The effects of the following enzymes – Celluclast 1.5L, hemicellulase, Pectinex Ultra SP‐L, Viscozyme L, Alcalase 0.6L and papain – on oil and protein extraction yields, and the level of reducing sugars in the extract were investigated. The results showed that Alcalase was most effective in enhancing oil and protein extraction yields. Papain was found to be superior to all carbohydrase enzymes but it gave lower yields than Alcalase. Celluclast 1.5L, hemicellulase, Pectinex Ultra SP‐L and Viscozyme L did not affect yields significantly but increased the level of reducing sugars in the extract. © 2002 Society of Chemical Industry     

A technique to improve network lifetime in mobile ad hoc networks

Energy is an important issue in mobile ad hoc networks (MANETs), and different energy‐aware routing mechanisms have been proposed to minimize the energy consumption in MANETs. Most of the energy‐aware routing schemes reported in the literature have considered only the residual battery capacity as the cost metric in computing a path. In this paper, we have proposed, an energy‐aware routing technique which considers the following parameters: (i) a cost metric, which is a function of residual battery power and energy consumption rate of participating nodes in path computation; (ii) a variable transmission power technique for transmitting data packets; and (iii) To minimize the over‐utilization of participating nodes, a limit is set on the number of paths that can be established to a destination through a participating node. The proposed scheme is simulated using Qualnet 4.5 simulator, and compared with Ad hoc On‐Demand Distance Vector (AODV) and Lifetime Enhancement Routing (LER). We observed that the proposed scheme performs better in terms of network lifetime and energy consumption. Copyright © 2014 John Wiley & Sons, Ltd.