Effect of swirl and number of swirler vanes on combustion characteristics of methane inverse diffusion flame

Journal of Mechanical Science and Technology - An experimental study is performed to explore the effect of swirl and number of swirler vanes on combustion characteristics of methane inverse...     

A Novel DUF569 Gene Is a Positive Regulator of the Drought Stress Response in Arabidopsis

In the last two decades, global environmental change has increased abiotic stress on plants and severely affected crops. For example, drought stress is a serious abiotic stress that rapidly and substantially alters the morphological, physiological, and molecular responses of plants. In Arabidopsis, several drought-responsive genes have been identified; however, the underlying molecular mechanism of drought tolerance in plants remains largely unclear. Here, we report that the “domain of unknown function” novel gene DUF569 (AT1G69890) positively regulates drought stress in Arabidopsis. The Arabidopsis loss-of-function mutant atduf569 showed significant sensitivity to drought stress, i.e., severe wilting at the rosette-leaf stage after water was withheld for 3 days. Importantly, the mutant plant did not recover after rewatering, unlike wild-type (WT) plants. In addition, atduf569 plants showed significantly lower abscisic acid accumulation under optimal and drought-stress conditions, as well as significantly higher electrolyte leakage when compared with WT Col-0 plants. Spectrophotometric analyses also indicated a significantly lower accumulation of polyphenols, flavonoids, carotenoids, and chlorophylls in atduf569 mutant plants. Overall, our results suggest that novel DUF569 is a positive regulator of the response to drought in Arabidopsis.     

Photocatalytic degradation of dyes and organic contaminants in water using nanocrystalline anatase and rutile TiO2

Nanocrystalline TiO₂ was synthesized by controlled hydrolysis of titanium tetraisopropoxide. The anatase phase was converted to rutile phase by thermal treatment at 1023 K for 11 h. The catalysts were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), Fourier-transform infrared absorption spectrophotometry (FT-IR) and N₂ adsorption (BET) at 77 K. This study compare the photocatalytic activity of the anatase and rutile phases of nanocrystalline TiO₂ for the degradation of acetophenone, nitrobenzene, methylene blue and malachite green present in aqueous solutions. The initial rate of degradation was calculated to compare the photocatalytic activity of anatase and rutile nanocrystalline TiO₂ for the degradation of different substances under ultraviolet light irradiation. The higher photocatalytic activity was obtained in anatase phase TiO₂ for the degradation of all substances as compared with rutile phase. It is concluded that the higher photocatalytic activity in anatase TiO₂ is due to parameters like band-gap, number of hydroxyl groups, surface area and porosity of the catalyst.     

Hydrodynamic study on radially cross-flow fluidized bed multi-staged ion-exchange column

A hydrodynamic study was carried out on our patented radially cross-flow fluidized bed staged column, with the salt laden water and solid resins flowing counter-currently, to determine the loading/flooding criterion for a stable operation of the column, and also to ascertain the mal-distribution in flow. Residense time distribution measurements were taken to address the latter part of the study. The data collected from the hydrodynamic measurements show a wider range of liquid and solid flowrates that can be used for the stable operation of the column, in comparison to that obtained in the conventional multi-staged column. The extent of mal-distribution or channeling is also relatively smaller in the former. The observations are consistent with the mass-transfer results obtained in our recent study, where the separation of dissolved solids using the radially cross-flow ion exchange column was found to be 40% larger than that in the conventional column.     

Low-fat sweet syrup cheese ball (Rosogolla) manufacturing and effect of lowering fat on quality

Low-fat sweet syrup cheese ball (Rosogolla) was manufactured by using low-fat cow milk and implementing six different combinations viz. type of chhana and two different concentrations (40 and 50o Brix) of cooking medium. Experimental Rosogolla samples and control were analysed for physico-chemical, textural and sensory properties. A 40o Brix concentration of sugar syrup as a cooking medium gave a highly acceptable low-fat Rosogolla. Average composition of low-fat Rosogolla is, moisture—49.83%, fat—4.66%, protein—11.85%, sorbitol—32.41% and ash—0.90%. Rheological properties of the most acceptable low-fat Rosogolla were hardness—6.78 N, springiness—5.72 mm, gumminess—3.2 N, chewiness—18.92 Nmm and stiffness—0.95 N/mm.     

Fabrication of a proton exchange membrane via blended sulfonimide functionalized polyamide

A novel linear non-fluorinated sulfonimide functionalized polyamide (SPA) polymer electrolyte was successfully synthesized via an aromatic sulfonimide monomer with superior thermal stability and superacidity. The aromatic sulfonimide remains stable below 220 °C. To fabricate membranes with strong mechanical strength and dimensional stability, the polymer was blended with various quantities of PVdF. The PVdF/SPA blend membranes exhibit an excellent capacity of water uptake and high dimensional stability. However, their proton conductivity was found to be substantially lower than that of Nafion 211. Analysis on the SEM images of the PVdF/SPA blend membranes reveals that the low proton conductivity is primarily caused by the large pore structures (>1 μm), which lead to breakdown of the continuous proton transport channels.     

Blends of polypropylene and ethylene octene comonomer with conducting fillers: Influence of state of dispersion of conducting fillers on electrical conductivity

Blends of polypropylene/ethylene octene comonomer (PP/EOC) with conducting fillers viz., carbon black (CB) and multiwall carbon nanotubes (MWNT) were prepared using melt mixing technique with varying filler concentration and blend compositions. Thermo gravimetric analysis studies indicated that presence of filler enhanced the thermal stability of PP/EOC blends. Morphological analysis revealed the formation of matrix‐dispersed droplet and co‐continuous type of morphology depending on the blend compositions. Significant reduction in droplet size and finer ligament thickness in co‐continuous structure were observed in the blends with filler due to compatibilization action. Fillers were found to be aggregated in the EOC phase irrespective of blends compositions and could be related to the affinity of the fillers toward EOC phase. The electrical conductivity of PP/EOC blends with CB and MWNT was found to be highest for 80/20 composition and decreased as EOC content increased. The percolation threshold of CB was between 10 and 15 wt% for the 80/20 and 70/30 blends whereas it was 15–20 wt% for blends with EOC content higher than 30 wt%. The percolation threshold was 2–3 wt% MWNT for PP/EOC blends. This was attributed to the aggregated filler network preferentially in the EOC phase. The melt‐rheological behavior of PP/EOC blends was significantly influenced in presence of both the fillers. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers