Birla Institute of Technology, Mesra

About: Birla Institute of Technology, Mesra is a education organization based out in Ranchi, India. It is known for research contribution in the topics: Computer science & Dielectric. The organization has 2801 authors who have published 4789 publications receiving 52426 citations. The organization is also known as: BIT.

Rainfall–runoff simulations of extreme monsoon rainfall events in a tropical river basin of India

Abstract: The present study analyzes the runoff response during extreme rain events over the basin of Subarnarekha River in India using soil and water assessment tool (SWAT). The SWAT model is configured for the Subarnarekha River basin with 32 sub-basins. Three gauging stations in the basin (viz., Adityapur, Jamshedpur and Ghatshila) were selected to assess the model performance. Daily stream flow data are taken from Central Water Commission, India—Water Resources Information System. Calibration and validation of the model were performed using the soil and water assessment tool-calibration uncertainty programs (SWAT-CUPs) with sequential uncertainty fitting (SUFI-2) algorithm. The model was run for the period from 1982 to 2011 with a calibration period from 1982 to 1997 and a validation period from 1998 to 2011. The sensitivity of basin parameters has been analyzed in order to improve the runoff simulation efficiency of the model. The study concluded that the model performed well in Ghatshila gauging station with a Nash–Sutcliffe efficiency (NSE) of 0.68 during calibration and 0.62 during validation at daily scale. The model, thus calibrated and validated, was then applied to evaluate the extreme monsoon rain events in recent years. Five extreme events were identified in Jamshedpur and Ghatshila sub-basins of Subarnarekha River basin. The simulation results were found to be good for the extreme events with the NSE of 0.89 at Jamshedpur and 0.96 at Ghatshila gauging stations. The findings of this study can be useful in runoff simulation and flood forecasting for extreme rainfall events in Subarnarekha River basin.

Study of bactericidal efficiency of magnetron sputtered TiO2 films deposited at varying oxygen partial pressure

Abstract: article i nfo TiO2 thin films have been deposited at different Ar:O2 gas ratios (20:80,70:30,50:50,and 40:60 in sccm) by rf reactive magnetron sputtering at a constant power of 200 W. The formation of TiO2 was confirmed by X-ray photoelectron spectroscopy (XPS). The oxygen percentage in the films was found to increase with an increase in oxygen partial pressure during deposition. The oxygen content in the film was estimated from XPS measurement. Band gap of the films was calculated from the UV-Visible transmittance spectra. Increase in oxygen content in the films showed substantial increase in optical band gap from 2.8 eV to 3.78 eV. The Ar: O2 gas ratio was found to affect the particle size of the films determined by a transmission electron microscope (TEM). The particle size was found to be varying between 10 and 25 nm. The bactericidal efficiency of the deposited films was investigated using Escherichia coli (E. coli) cells under 1 h UV irradiation. The growth of E. coli cells was estimated through the Optical Density measurement by UV-Visible absorbance spectra. The qualitative analysis of the bactericidal efficiency of the deposited films after UV irradiation was observed through SEM. A correlation between the optical band gap, particle size and bactericidal efficiency of the TiO2 films at different argon:oxygen gas ratio has been studied.

Screening of bioemulsifier-producing micro-organisms isolated from oil-contaminated sites

Abstract: Eighty-eight micro-organisms were isolated from oil-contaminated soils and checked for their extracellular bioemulsifier producing potential. The micro-organisms were screened on the basis of oil spread, drop collapse and emulsification index. Most efficient strains were characterized as Lysinibacillus sp. SP1025 and Bacillus cereus SP1035. In Lysinibacillus sp. SP1025, the E-24 index, surface tension and production of crude bioemulsifier were found to be 83.3 % with diesel, 34.20 ± 0.03 mN/m and 3.07 ± 0.62 g/L, respectively, whereas in the case of Bacillus cereus SP1035, the E-24 index, surface tension and production of crude bioemulsifier recorded were 76.5 % with diesel, 43.42 ± 0.03 mN/m and 3.90 ± 0.3 g/L. Crude biomemulsifier produced by selected micro-organisms was stable, withstanding a wide temperature and pH range with an E-24 Index value greater than 50 %. All emulsions formed were oil-in-water type. Emulsions formed with tested aliphatic and aromatic hydrocarbons, except those formed with ester based oils, were 100 % stable with the entire organic layer converted into emulsion. To the best of our knowledge this is the first report for bioemulsifier production from the genus Lysinibacillus.