The National Institute of Technology Raipur is a technical institution funded by the Government of India,located in Raipur, Chhattisgarh. Founded in 1956 as Govt. College of Mining & Metallurgy with two engineering disciplines, mining and metallurgy, the institute is one of the oldest of its kind in India citation??. Currently it is one of the National Institutes of Technology, which have been accorded Institute of National Importance status by the National Institutes of Technology Act, 2007.The institute offers 2 undergraduate and 2 post graduate programmes M.Tech. and M.C.A. in 11 engineering disciplines and Architecture. Wikipedia.
Nath G.,National Institute of Technology Raipur
Advances in Space Research | Year: 2011
The propagation of a strong cylindrical shock wave in an ideal gas with azimuthal magnetic field, and with or without axisymmetric rotational effects, is investigated. The shock wave is driven out by a piston moving with time according to power law. The ambient medium is assumed to have radial, axial and azimuthal component of fluid velocities. The fluid velocities, the initial density and the initial magnetic field of the ambient medium are assumed to be varying and obey power laws. Solutions are obtained, when the flow between the shock and the piston is isothermal. The gas is assumed to have infinite electrical conductivity and the angular velocity of the ambient medium is assumed to be decreasing as the distance from the axis increases. It is expected that such an angular velocity may occur in the atmospheres of rotating planets and stars. The shock wave moves with variable velocity and the total energy of the wave is non-constant. The effects of variation of the initial density and the Alfven-Mach number on the flow-field are obtained. A comparison is also made between rotating and non-rotating cases. © 2010 COSPAR. Published by Elsevier Ltd. All rights reserved.
Mishra D.,National Institute of Technology Raipur
Computers and Mathematics with Applications | Year: 2014
The extension of the nonnegative splitting for rectangular matrices called proper nonnegative splitting is proposed first. Different convergence and comparison theorems for the proper nonnegative splittings are established. The notion of double nonnegative splitting is then generalized to rectangular matrices. Finally, different convergence and comparison results are presented for this decomposition. The case for singular square matrices is also studied. © 2013 Elsevier Ltd. All rights reserved.
Gupta P.,National Institute of Technology Raipur |
Parkhey P.,National Institute of Technology Raipur
Bioresource Technology | Year: 2015
Response surface methodology was used to optimise a two-step process of cellulase mediated saccharification of rice straw by an isolated bacterium Lysinibacillus sphaericus. CMC concentration, yeast extract, pH and incubation temperature were optimised for cellulase production using a central composite design and their optimum values were determined to be 4.3% (w/v), 2.1% (w/v), 6.2 and 45.2. °C respectively. The CMCase activity at these values was 5.16. ±. 0.07. U/ml, which was 2.5. times that of the un-optimised system. Similarly, pretreated rice straw, enzyme load, incubation time and Tween-80 concentrations were optimised for enhanced saccharification of rice straw by optimised cellulase preparations, and their optimum values were calculated as 1.84% (w/v), 40. U, 57.4. h and 0.76. mM respectively. A percent saccharification of 69.5% was reported at optimal conditions. HPLC analysis revealed that hydrolysate produced at optimal conditions of saccharification constituted 70.8% of glucose. © 2014 Elsevier Ltd.
Nath G.,National Institute of Technology Raipur
Advances in Space Research | Year: 2012
A self-similar solution is obtained for one dimensional adiabatic flow behind a cylindrical shock wave propagating in a rotating dusty gas in presence of heat conduction and radiation heat flux with increasing energy. The dusty gas is assumed to be a mixture of non-ideal (or perfect) gas and small solid particles, in which solid particles are continuously distributed. It is assumed that the equilibrium flow-condition is maintained and variable energy input is continuously supplied by the piston (or inner expanding surface). The heat conduction is expressed in terms of Fourier's law and the radiation is considered to be of the diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient α R are assumed to vary with temperature only. In order to obtain the similarity solutions the initial density of the ambient medium is assumed to be constant and the angular velocity of the ambient medium is assumed to be decreasing as the distance from the axis increases. The effects of the variation of the heat transfer parameters and non-idealness of the gas in the mixture are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) the ratio of the density of solid particles to the initial density of the gas on the flow variables are also investigated. © 2011 COSPAR. Published by Elsevier Ltd. All rights reserved.
Khare A.,National Institute of Technology Raipur
Journal of Physics and Chemistry of Solids | Year: 2012
This work investigates the effects of the temperature, deposition time and annealing ambient on the electro-optical and structural properties of nano crystalline (Cd-Zn)S films prepared by chemical bath deposition (CBD). The deposited films being uniform and adherent to the glass substrates are amorphous in nature and the crystallinity as well as the grain size is found to increase on post-deposition annealing. The obtained specimens are thoroughly characterized before and after annealing paying particular attention to their structure, composition and morphology. Annealing in air reduces the extent of disorder in grain boundaries and energy band-gap. A correlation between the structural and optical properties is investigated in detail. The surface morphology and structural properties of the as-deposited and annealed (Cd-Zn)S thin films are studied using X-ray diffraction (XRD), scanning electron microscope (SEM) and optical transmission spectra. The optical transmission spectra are recorded within the range of 300-800 nm and 300-900 nm. The electroluminescent (EL) intensity is found to be maximum at a particular temperature, which decreases with further increase in temperature and peaks of photoluminescent (PL) and EL spectra are centered at 546 nm and 592 nm. The emission intensity also increases with increasing thickness of the film. © 2012 Elsevier Ltd.
Upadhyay L.S.B.,National Institute of Technology Raipur |
Verma N.,National Institute of Technology Raipur
Biosensors and Bioelectronics | Year: 2015
Determination of phosphate ions concentration is very important from both, environmental and clinical point of view. In this study, a simple and novel conductometric biosensor for indirect determination of the phosphate ions in aqueous solution has been developed. The developed biosensor is based on the inhibition of immobilized alkaline phosphatase activity, in the presence of the phosphate ions. This is the first time we developed a mono-enzymatic biosensor for indirect estimation of phosphate ions. The developed biosensor showed a broad linear response (as compared to other reported biosensors) for phosphate ions in the range of 0.5-5.0. mM (correlation coefficient=0.995), with a detection limit of 50. μM. Different optimized parameters were obtained as the buffer concentration of 30. mM, substrate concentration of 1.0. mM, and a pH of 9.0. All the optimized parameters were analyzed by analysis of variance, and were found to be statistically significant at a level of α=0.05. The developed biosensor is also suitable to determine the serum phosphate concentration, with a recovery of 86-104%, while a recovery of 102% was obtained from the water samples that were spiked with 500. μM phosphate. A relative standard deviation in the conductance response for five successive measurements (n=5) did not exceed 7%, with a shelf life of 30 days. With a lower detection limit and a higher recovery, the biosensor provides a facile approach for phosphate estimation in biological fluids. © 2015 Elsevier B.V.
Rai H.,National Institute of Technology Raipur |
Yadav A.,National Institute of Technology Raipur
Expert Systems with Applications | Year: 2014
Iris based authentication system is essentially a pattern recognition technique that makes use of iris patterns, which are statistically unique, for the purpose of personal identification. In this study, a novel method for recognition of iris patterns is considered by using a combination of support vector machine and Hamming distance. The zigzag collarette area of the iris is selected for iris feature extraction because it captures the most important areas of iris complex pattern and higher recognition rate is achieved. The proposed approach also used parabola detection and trimmed median filter for the purpose of eyelid and eyelash detection & removal, respectively. The proposed method is computationally effective as well as reliable with a recognition rate of 99.91% and 99.88% on CASIA and Chek image database respectively. © 2012 Elsevier B.V. All rights reserved.
Nath G.,National Institute of Technology Raipur
Research in Astronomy and Astrophysics | Year: 2010
Non-similarity solutions are obtained for one-dimensional isothermal and adiabatic flow behind strong cylindrical shock wave propagation in a rotational axisymmetric dusty gas, which has a variable azimuthal and axial fluid velocity. The dusty gas is assumed to be a mixture of small solid particles and perfect gas. The equilibrium flow conditions are assumed to be maintained, and the density of the mixture is assumed to be varying and obeying an exponential law. The fluid velocities in the ambient medium are assumed to obey exponential laws. The shock wave moves with variable velocity. The effects of variation of the mass concentration of solid particles in the mixture, and the ratio of the density of solid particles to the initial density of the gas on the flow variables in the region behind the shock are investigated at given times. Also, a comparison between the solutions in the cases of isothermal and adiabatic flows is made. © 2010 National Astronomical Observatories of Chinese Academy of Sciences and IOP Publishing Ltd.
Upadhyay L.S.B.,National Institute of Technology Raipur
Indian Journal of Biotechnology | Year: 2012
Urease inhibitors possess a wide application in agriculture, clinical science and understanding of enzyme kinetics. These inhibitors play a significant role in reducing the loss of nitrogen from urea fertilizer in the form of volatile ammonia and, thus, improve the utility of urea based fertilizers. Their impact as an effective drug against urease producing bacterial infection is well documented. The study of urease inhibitors is useful in providing an insight in the catalytic mechanism. This article is an attempt to compile the various urease inhibitors used so far by researchers.
Sahoo B.K.,National Institute of Technology Raipur
Journal of Materials Science | Year: 2012
We have investigated the effect of piezoelectric (PZ) polarization property on group velocity of phonons in binary as well as in ternary wurtzite nitrides. It is found that with the presence of PZ polarization property, the phonon group velocity is modified. The change in phonon group velocity due to PZ polarization effect directly depends on piezoelectric tensor value. Using different piezoelectric tensor values recommended by different workers in the literature, percent change in group velocities of phonons has been estimated. The Debye temperatures and frequencies of binary nitrides GaN, AlN, and InN are also calculated using the modified group velocities. For ternary nitrides Al x Ga (1-x)N, In x Ga (1-x)N, and In x Al (1-x)N, the phonon group velocities have been calculated as a functions of composition. A small positive bowing is observed in phonon group velocities of ternary alloys. Percent variations in phonon group velocities are also calculated for a straightforward comparison among ternary nitrides. The results are expected to show a change in phonon relaxation rates and thermal conductivity of III-nitrides when piezoelectric polarization property is taken into account. © 2011 Springer Science+Business Media, LLC.