Singh P.K.,Rbs College |
Chauhan R.S.,Rbs College
Journal of Applied Polymer Science | Year: 2010
The study of optical and thermally stimulated electrical properties such as optical band gap, refractive index, X-ray spectra, SEM spectra, thermally stimulated discharge current (TSDC), differential scanning calorimetry (DSC) have been undertaken in ZnO nanoparicle filled polystyrene nanocomposite thin film of 30 lm thickness. The appearance of single TSDC peak at temperature 408 ± 5 K in nanocomposite samples shows the charge carriers injected from deeper trapping levels. It is due to the modification of surface and bulk properties of polystyrene by filling of ZnO nanoparticles. In other hand, the strong interaction of nanoparticles with polymer matrix is the expected reason of improvement of crystallite size, optical energy band gap, refractive index, TSDC, glass transition temperature, and charge storage. It is confirmed from SEM images that the modifications of these properties are caused by creation of clusters in amorphous-crystalline boundaries of pristine polystyrene. © 2010 Wiley Periodicals, Inc.
Rathore B.S.,Rbs College |
Singh K.S.,Rbs College
Journal of Thermal Analysis and Calorimetry | Year: 2013
Swift heavy ion beam irradiation induces modification in the dielectric properties and surface morphologies of polycarbonate (PC) films. The PC films were irradiated by 55 MeV energy of C5+ beam at various ions fluences ranging from 1 × 1011 to 1 × 1013 ions cm-2. The dielectric properties (i.e., dielectric constant, dielectric loss, and AC conductivity) and surface morphologies of pristine and SHI beam irradiated PC films were investigated by dielectric measurements, atomic force microscopy (AFM), and optical microscopy. The dielectric measurements show that the dielectric constant, dielectric loss, and AC conductivity increase with ion fluences and temperature, however, the dielectric constant and AC conductivity decrease while dielectric loss increases with frequency. AFM shows the increase in average roughness values with ion fluences. The change of color in PC films has been observed from colorless to yellowish and then dark brown with increases of ion fluence by using optical microscopy. © 2012 Akadémiai Kiadó, Budapest, Hungary.
Singh S.R.,House Number 27 |
Singh A.P.,Rbs College
International Journal of Environmental Research | Year: 2012
Presence of heavy metals in the aquatic systems has become a serious problem. As a result, there has been a great deal of attention given to new technologies for removal of heavy metal ions from contaminated waters. Adsorption is one of the effective methods for removal of toxic heavy metal such as chromium (VI). In the present study, adsorbent is prepared from rice husk, a low cost by product from a rice mill. The rice husk carbon is activated using H3PO4 (40%). The stock solution of Cr (VI) is prepared by dissolving 2.828 gm of potassium dichromate (Central Drug House (CDH), India) in 1 litre of demineralized water. Batch mode experiments are done. The effect of various parameters like adsorbent dose, pH and contact time are studied. The studies demonstrate that the Rice Husk Carbon (RHC) has a significant capacity for adsorption of Cr (VI) from aqueous solution. The RHC characteristics are reported as FTIR and other physical properties are tabulated average. The break through capacity for Cr (VI) (100 mg/l, pH 2) is on average 38.1 mg/g. The adsorption of chromium (VI) was found to be maximum(93-94%) at low values of pH (around 2) for the carbon dosage of 1000mg/L and nearly 100% for carbon dosage of 1200mg/L. RHC exhibits high degree of selectivity for Cr (VI) adsorption. The adsorbent prepared from rice husk carbon is efficient and it is proposed that it can be conveniently employed as a low cost alternative in the treatment of industrial waste water.
Goyal S.K.,A.P.S. University |
Samsher,A.P.S. University |
Goyal R.K.,RBS College
International Journal of Food Sciences and Nutrition | Year: 2010
Studies revealed that Stevia has been used throughout the world since ancient times for various purposes; for example, as a sweetener and a medicine. We conducted a systematic literature review to summarize and quantify the past and current evidence for Stevia. We searched relevant papers up to 2007 in various databases. As we know that the leaves of Stevia plants have functional and sensory properties superior to those of many other high-potency sweeteners, Stevia is likely to become a major source of high-potency sweetener for the growing natural food market in the future. Although Stevia can be helpful to anyone, there are certain groups who are more likely to benefit from its remarkable sweetening potential. These include diabetic patients, those interested in decreasing caloric intake, and children. Stevia is a small perennial shrub that has been used for centuries as a bio-sweetener and for other medicinal uses such as to lower blood sugar. Its white crystalline compound (stevioside) is the natural herbal sweetener with no calories and is over 100-300 times sweeter than table sugar. © 2010 Informa UK Ltd.
Kushwah B.S.,Bichpuri Rbs College |
Bhadauria S.,Rbs College
Journal of Applied Polymer Science | Year: 2010
Laccases from Pleurotus ostreatus was extracted from the Shaken flask cultures of Pleurotus ostreatus grown at 25°C with continuous agitation (110 rpm.) in baffled 1000 mL Erlenmeyer flasks containing 200 mL medium. The basal GYP medium used for cultures contained 20 g glucose l-1, 5 g yeast extract l-1, 5 g peptone from casein l-1, and 1 g MgSO4.7H2O l-1. The pH was adjusted to 5.0 with H3PO4 before sterilization. The kinetics of oxidation reactions catalyzed by laccases was studied using 2,2′- azino-bis (3-ethylbenzthiazoline-6-sulphonic acid). The laccases showed lower specific activity and higher activity in nonpolar organic solvents. A biosensor using laccases was constructed for the determination of phenol. The enzyme was extracted from Pleurotus ostreatus and entrapped in agarose-guar gum composite biopolymer matrix. Phenol was determined by direct reduction of biocatalytically liberated quinone species at -0.1 V versus Ag/AgCl (3M KCl). The response was found to be linear and concentration dependent.It has a shelf life of more than 2 months when stored at 4°C. © 2009 Wiley Periodicals, Inc.
Pokhriyal A.,Rbs College |
Lehri S.,Institute of Information and Computer science
Journal of Theoretical and Applied Information Technology | Year: 2010
A new approach for fingerprint verification, based on wavelets and pseudo Zernike moments (PZMs), is discussed. PZMs are robust to noisy images, invariant to rotation and have a good image reconstruction capability . PZMs have been used for global analysis and so they are used to extract global features (the shape of the fingerprint image). Wavelets are good at local analysis and so they help to extract local features (minutiae) from a fingerprint. Therefore, this hybrid approach extracts most significant features from the fingerprint images and achieve better verification rate. Different types of wavelets are used for the study but the result shows that Symmlet orthonormal wavelet of order 8 gives best verification rate. © 2005 - 2010 JATIT. All rights reserved.
Singh K.S.,Rbs College
Physica B: Condensed Matter | Year: 2012
On the basis of the free volume theory of Grüneisen parameter (γ) and using the calculus of indeterminates, it is found that the second order Grüneisen parameter (q) and the second pressure derivative of bulk modulus (KK″) change in a similar manner in the limit of extreme compression. The ratio of q and KK″ becomes finite at infinite pressure. This finding has been used further to obtain a relationship for the third order Grüneisen parameter λ in terms of pressure derivatives of bulk modulus up to the third order. The results are found to be consistent with the identities obtained recently by Shanker et al.  using the free volume theory. © 2011 Elsevier B.V. All rights reserved.
Rathore B.S.,Rbs College |
Rathore B.S.,Shekhawati Institute of Engineering and Technology
Radiation Effects and Defects in Solids | Year: 2014
Polycarbonate/polystyrene bilayer films prepared by solvent-casting method were irradiated with 55 MeV carbon ion beam at different fluences ranging from 1 × 1011 to 1 × 1013 ions cm-2. The structural, optical, surface morphology and dielectric properties of these films were investigated by X-ray diffraction (XRD), UV-visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, optical microscopy and dielectric measurements. The XRD pattern shows that the percentage of crystallinity decreases while inter-chain separations increase with ion fluence. UV-visible spectroscopy shows that the energy band gap decreases and the number of carbon atoms in nanoclusters increase with the increase in ion fluences. The refractive index is also found to decrease with the increase in the ion fluence. Optical microscopy shows that after irradiation polymeric bilayer films color changes with ion fluences. The FTIR spectra evidenced a very small change in cross-linking and chain scissoring at high fluence. Dielectric constant decreases while dielectric loss and AC conductivity increase with ion fluences. © 2014 Taylor & Francis.
Singh A.K.,RBS College |
Singh D.P.,RBS College
International Journal of Engineering, Transactions B: Applications | Year: 2013
The purpose of this study is to develop a mathematical model for studying the magnetic field effect on blood flow through an axially non-symmetric but radially symmetric atherosclerotic artery. Herschel- Bulkley equation has been taken to represent the non-Newtonian character of blood. The response of magnetic field, stenosis height, shape parameter on velocity, volumetric flow rate in stenotic section and wall shear stress at the surface of stenosis are revealed analytically and graphically.
Chauhan V.,Rbs College |
Singh O.P.,Rbs College
Advances in Space Research | Year: 2010
The temporal and seasonal variations of Total Electron Content (TEC) are studied at Agra (Geographic Lat. 27.17°N, Long. 78.89°E, Dip: 41.4°), India, which is in the equatorial anomaly region, for a period of 12 months from 01 January to 31 December, 2007 using a Global Positioning System (GPS) receiver. The mean TEC values show a minimum at 0500 h LT (LT = UT + 5.5 h) and a peak value at about 1400 h LT. The lowest TEC values are observed in winter whereas largest values are observed in equinox and summer. Anomalous variations are found during the period of magnetic disturbances. These results are compared with the TEC derived from IRI-2007 using three different options of topside electron density, NeQuick, IRI01-corr, and IRI-2001. A good agreement is found between the TEC obtained at Agra and those derived from IRI models. © 2010 COSPAR. Published by Elsevier Ltd. All rights reserved.