Simulation studies on a rotating ring disk electrode: Effects of ionic migration with kinetic complication-disk results

In continuation to my previous work (Guha S. AIChE J. 2013;59(4):1390-1399), in this work, effects of ionic migration are evaluated for disk region of a rotating ring disk electrode system by numerically solving complex differential equations, developed for mass transfer along with kinetic complication in presence of ionic migration under limiting current condition. The system for simulation is 0.01 M Fe₂(SO₄)₃ solution with H₂SO₄ as supporting electrolyte. Simulation cases are presence and absence of ionic migration with kinetic complication (oxidation of Fe²⁺ to Fe³⁺ under O₂ pressure). Results show that concentration boundary layer thickness of reactant Fe³⁺ reduces appreciably and steady-state disk current reduces substantially in presence of migration. Simulated steady-state disk current in absence of migration case agrees well with published data. Results indicate higher Fe²⁺ concentration in presence of migration and thereby higher rate of oxidation of Fe²⁺ to Fe³⁺ at all rate constant values.     

Isolation and identification of caffeine-degrading bacteria from coffee plantation area

Decaffeination of food and beverage products is in high demand. In this study, a caffeine-degrading bacterium Burkholderia spp. was isolated from coffee plantation area of Chiang Mai province of Thailand. The bacterial isolates were first identified by morphological, physiological, and biochemical tests followed by 16S rDNA analysis. The bacterial isolate of Burkholderia spp. showed 45.5% of caffeine degradation in caffeine containing media (2.5 g/L) after 110 h of incubation period. Burkholderia spp. showed only 2.6% caffeine degradation when exposed to high concentrations of caffeine containing medium (20 g/L). The growth rate of Burkholderia spp. declined with the increase in the caffeine concentration, which indicated the inhibiting effect of caffeine at very high concentrations. The maximum growth rate of 0.053 h^?1 was observed at 2.5 g/L of caffeine. Overall due to high caffeine tolerance and biodegradation of caffeine, Burkholderia spp. can be effectively used to degrade caffeine from agro-industrial wastes targeted for value added food applications and environmental remediation.     

Adaptive hough transform with optimized deep learning followed by dynamic time warping for hand gesture recognition

Multimedia Tools and Applications - Hand gesture is a natural interaction method, and hand gesture recognition is familiar in human–computer interaction. Yet, the variations, as well as the...     

Survey on various architectures of preamplifiers for electroencephalogram (EEG) signal acquisition

Microsystem Technologies - Modern-day biomedical science and technology have progressed with implantable neural recording systems. There is a demand for miniaturised devices that can be emplaced...     

Enhanced granulation by natural ionic polymer additives in UASB reactor treating low-strength wastewater

Effect of natural ionic polymer additives on granulation in lab-scale UASB reactors treating low-strength synthetic wastewater (COD 750-850 mg/L) was examined. The organic loading rate was 1.477+/-0.118 kgCOD/m3/day. Under identical conditions four similar reactors were operated in parallel with the following additives: control with no additive, anionic part of Reetha (Sapindus trifoliata) extract, cationic part of Reetha extract, and Chitosan. By the end of the study period, Chitosan as an additive produced largest granules with mean size of 0.15 mm closely followed by the cationic fraction of the Reetha extract with mean size of 0.144 mm, and anionic fractions of the Reetha extract with 0.139 mm. Control reactor with no additives had the smallest size granules with mean size of 0.128 mm. The fraction of granules in the sludge bed of size >0.1 mm showed similar trend. The largest granule size observed in the reactors with additives was 4-5mm as compared to 2 mm in the control reactor. Cationic polymers were more effective additives for enhancing sludge granulation. Exo-cellular protein, lipid, sugar and total polymer increased with granulation in the reactors. A COD removal efficiency of 95-98% was achieved in all the reactors.     

Morphological,Mechanical Property Analysis and Comparative Study over Structural Properties of CVD TiN Film Grown under Different Substrate Temperature in Nitrogen Gas Atmosphere

Silicon - Titanium Nitride (TiN) thin films were deposited by thermal chemical vapor deposition process (CVD) over Si (100) substrate under different substrate temperatures. Morphological,...