The Maharaja Sayajirao University of Baroda is a university in the city of Vadodara, in Gujarat state, India. Originally known as the Baroda College of Science , it became a university in 1949 after the independence of the country. It was later renamed after its benefactor Maharaja Sayajirao Gaekwad III, the former ruler of Baroda State belonging the royal Gaekwad dynasty of the Marathas.It is a teaching and residential university and the only university in Gujarat whose medium of instruction is English for all courses. India Today has ranked it at tenth place in their list of India's best universities. while Hindustan Times has ranked it at sixth place. Wikipedia.
Anand A.,M. S. University of Baroda |
Javidi B.,University of Connecticut
Optics Letters | Year: 2010
Generally, 3D digital holographic microscopy requires the interference of the object wave with a known reference beam under coherent illumination to perform numerical focusing. This configuration may be challenging for some applications, including the use of exotic wavelengths such as x rays, miniaturized instrumentation, etc. Single-beam intensity measurement followed by phase retrieval techniques is attractive for wavefront sensing and reconstruction, including applications with low coherence. We use this method to construct a 3D microscope using volume speckle fields. Transparent phase objects are investigated using this principle. To the best of our knowledge, this is the first report on the application of this principle applied to microscopy. © 2010 Optical Society of America.
Zaveri N.,Sardar Vallabhbhai National Institute of Technology, Surat |
Chudasama A.,M. S. University of Baroda
International Journal of Electrical Power and Energy Systems | Year: 2012
This paper gives a new insight into the concept of load compensation using shunt active filter (SAF) under ideal and non-ideal source voltage conditions. A novel approach based on an improved instantaneous active and reactive current component method is proposed. The performance of the proposed control strategy has been compared with instantaneous reactive power theory, symmetrical component theory and dq theory. SAF has been realized by three-phase voltage source converter. Reference currents generated by control strategies has been tracked by a SAF in a hysteresis band control scheme. The performance of the proposed scheme is evaluated in terms of reactive power compensation, reduction in magnitude of source currents, compensator currents, and harmonic compensation as per IEEE-519 standard. To ascertain the viability of the proposed control algorithm, the performance is evaluated under different source voltage conditions with the IEEE Standard-1459 power definitions. Variation in magnitude as well as harmonic content of source voltage has been considered. Under balanced sinusoidal source voltage condition, all control strategies congregate to similar results. Under unbalanced sinusoidal source voltage condition, dq theory and proposed theory have shown similar performance. However, under distorted source voltage conditions, an improved instantaneous active and reactive current component theory presents superior performance. A three-phase, three-wire distribution system supplying non-linear load is considered for simulation study. Simulation results from a complete model of SAF are presented to validate and compare the control strategies. © 2012 Elsevier Ltd. All rights reserved.
Brahmkhatri V.,M. S. University of Baroda |
Patel A.,M. S. University of Baroda
Applied Catalysis A: General | Year: 2011
12-Tungstophosphoric acid anchored to SBA-15 was synthesized and characterized by various physico-chemical techniques such as TGA, FT-IR, DRS, XRD, N2 adsorption-desorption, solid state NMR (31P and 29Si), SEM and TEM. The use of synthesized catalyst was explored for biodiesel production by esterification of free fatty acid, oleic acid with methanol. Influence of various reaction parameters (such as catalyst concentration, acid/alcohol molar ratio and reaction temperature) on catalytic performance was studied. The catalyst shows high activity in terms of conversion of oleic acid as well as high turnover frequency of 9.3 min-1. It also shows potential of being used as recyclable catalyst material after simple regeneration. Kinetic investigation reveals that the esterification reaction of oleic acid with methanol follows a first order dependency on the concentration of the oleic acid and the catalyst. The influence of temperature on rate constant was also studied and the activation energy was found to be 44.6 kJ mol-1. As an application, preliminary study was carried out for biodiesel production from waste cooking oil, as feedstock without any pre-treatment, with methanol. Studies show that the catalyst can be used for biodiesel production from waste cooking oil under mild conditions. © 2011 Elsevier B.V. All rights reserved.
Patel A.,M. S. University of Baroda |
Narkhede N.,M. S. University of Baroda
Energy and Fuels | Year: 2012
Heterogeneous acid catalysts comprised of 12-tungstophosphoric acid (10-40 %) and zeolite Hβ were synthesized, and 30 % loaded catalyst was characterized by various physicochemical techniques. The use of synthesized catalyst was explored for biodiesel production by esterification of free fatty acid, oleic acid with methanol. The effect of various reaction parameters such as catalyst concentration, acid/alcohol molar ratio, and temperature were studied to optimize the conditions for maximum conversion. The catalyst showed high activity in terms of high conversion (84%) and a high turnover number, 1048. The kinetic study as well as Koros-Nowak test were carried out, and it was found that esterification of oleic acid follows first order kinetics with the calculated activation energy E a = 45.2 kJ mol -1 and pre-exponential factor A = 5.4 × 10 4 min -1. The catalyst showed potential of being used as a recyclable catalytic material after simple regeneration without significant loss in conversion. As an application, preliminary studies were carried out for biodiesel production from waste cooking oil and jatropha oil, as feedstock over present catalyst. © 2012 American Chemical Society.
Sharma R.K.,M. S. University of Baroda |
Arora D.S.,Guru Nanak Dev University
Critical Reviews in Microbiology | Year: 2015
Microbial degradation of lignocellulosic materials brings a variety of changes in their bio-physicochemical properties. Lower digestibility of various agricultural residues can be enhanced by microbial treatment. White rot fungi are the potential candidates, which can improve the nutritional quality of lignocellulosic residues by degrading lignin and converting complex polysaccharides into simple sugars. Changes in physical qualities of lignocellulosics that is texture, colour and aroma have been an interesting area of study along with chemical properties. Degradation of lignocellulose not only upgrades the quality of degraded biomass, but helps simultaneous production of different commercial enzymes and other by products of interest. The review is focused on fungal degradation of lignocellulosics, resultant changes in physicochemical properties and nutritional value. © 2015 Informa Healthcare USA, Inc.
Sharma D.S.,M. S. University of Baroda
European Journal of Mechanics, A/Solids | Year: 2015
Abstract A General solution for determining the stress field around polygonal hole in a laminated composite infinite plate subjected to arbitrary biaxial loading, with layers of arbitrary fiber orientations and stacking sequence, is obtained using complex variable approach. The effect of material parameters, hole geometry, fiber orientation angle and loading pattern, on stress field around hole is studied. © 2015 Elsevier Masson SAS.
Srinandan C.S.,M. S. University of Baroda
Biofouling | Year: 2010
Bacterial biofilms adapt and shape their structure in response to varied environmental conditions. A statistical methodology was adopted in this study to empirically investigate the influence of nutrients on biofilm structural parameters deduced from confocal scanning laser microscope images of Paracoccus sp.W1b, a denitrifying bacterium. High concentrations of succinate, Mg(++), Ca(++), and Mn(++) were shown to enhance biofilm formation whereas higher concentration of iron decreased biofilm formation. Biofilm formed at high succinate was uneven with high surface to biovolume ratio. Higher Mg(++) or Ca(++) concentrations induced cohesion of biofilm cells, but contrasting biofilm architectures were detected. Biofilm with subpopulation of pillar-like protruding cells was distributed on a mosaic form of monolayer cells in medium with 10 mM Mg(++). 10 mM Ca(++) induced a dense confluent biofilm. Denitrification activity was significantly increased in the Mg(++)- and Ca(++)-induced biofilms. Chelator treatment of various biofilm ages indicated that divalent cations are important in the initial stages of biofilm formation.
Patel A.,M. S. University of Baroda |
Singh S.,M. S. University of Baroda
Fuel | Year: 2014
Environmentally benign solid acid catalysts consisting of 12-tungstophosphoric anchored to MCM-41 and zirconia were synthesized and characterized. The efficacy for the esterification of glycerol, a value added byproduct from biodiesel production was investigated. Conditions for maximum conversion was optimized by varying different reaction parameters, such as, glycerol/acetic acid mole ratio, amount of the catalyst, reaction time and reaction temperature. The kinetic study was carried out, and it was found that esterification of glycerol follows first order kinetics and the rates are not mass transfer limited. Also activation energy and ΔG was determined. The difference in % conversion as well as selectivity was correlated with the nature of supports, value of activation energy as well as ΔG. The catalysts showed potential of being used as recyclable material after simple regeneration without significant loss in conversion. © 2013 Elsevier Ltd. All rights reserved.
Patel A.,M. S. University of Baroda |
Narkhede N.,M. S. University of Baroda
Catalysis Science and Technology | Year: 2013
Mono-vacant silicotungstate anchored to MCM-41 was synthesized by a direct post-synthesis grafting method and characterized by BET surface area measurements, FT-IR, 29Si MAS NMR, XRD and TEM. The catalytic application of the material was established for acid catalyzed synthesis of biodiesel via esterification of oleic acid and transesterification of different edible and non-edible oils such as waste cooking oil, jatropha oil, sunflower oil, cotton seed oil and mustard oil. A kinetic study was carried out for the esterification of oleic acid and it was found that esterification of oleic acid follows first order kinetics with the calculated activation energy Ea = 49.8 kJ mol-1 and pre-exponential factor A = 8.7 × 10 4 min-1. The expected mechanism for the biodiesel synthesis via esterification and transesterification has also been proposed. This journal is © The Royal Society of Chemistry.
Nerurkar A.S.,M. S. University of Baroda
Advances in Experimental Medicine and Biology | Year: 2010
Lichenysins are most potent anionic cyclic lipoheptapeptide biosurfactants produced by Bacillus licheniformis on hydrocarbonless medium with mainly glucose as carbon source. They have the capacity to lower the surface tension of water from 72 to 27 mN/m. Based on species specific variations they are named lichenysin A, B, C, D, G and surfactant BL86. Th lowest ever interfacial tension against decane of 0.006 mN/m is obtained with acid precipitated lichenysin B. Surfactant BL86 and lichenysin B have recorded lowest ever CMC of 10 mg/L by any surfactant under optimal conditions. Surface and interfacial tension lowering ability bears significance in the context of oil recovery from oil reservoir. Similarity exists between structure and biosynthesis of surfactin and lichenysin. Surfactin being the most studied of the two, understanding its structure and biosynthesis gives an insight into the structure and biosynthesis of lichenysin. Lichenysin is synthesized by a multienzyme complex, lichenysin synthetase (LchA/ Lic) encoded by 32.4 (26.6 kb) lichenysin operon lchA (lie). Thstructure of lichen ysin and its operon indicate the nonribosomal biosynthesis with the same multifunctional modular arrangement as seen in surfactin synthetase SrfA. Th Ich A operon consists of lchAA-AC (lic A-C) and lchA TE (licTE) genes encoding the proteins LchAA, LchAB, LchAC and thioesterase LchA-TE. Tfe liccA (lchAA) gene is 10,746 bp and codes for a 3,582 amino acids protein, licB (lchAB) gene is 10,764 bp and codes for a similar sized protein, while licC (lchAC) gene is 3,864 bp and codes for protein containing 1,288 amino acid. Th biotechnological potential of lichenysin in MEOR has triggered research on structure-activity relationship. Both the nature of peptide and fatty acid dictate the activity of the biosurfactant. Tailormade biosurfactant with desired attributes can be obtained from engineered synthetases. Basic studies are lacking on mechanism of biosynthesis by lichenysin synthetase however, studies on various aspects of lichenysin including regulation are expected to swell in coming years. © 2010 Landes Bioscience and Springer Science+Business Media.