R.G. Sonkawade

Comparative study of natural radioactivity levels in soil samples from the Upper Siwaliks and Punjab, India using gamma-ray spectrometry

Natural radioactive materials under certain conditions can reach hazardous radiological levels. So, it becomes necessary to study the natural radioactivity levels in soil to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. The natural radionuclide (226Ra, 232Th, and 40K) contents in soil were determined for 26 locations around the Upper Siwaliks of Kala Amb, Nahan and Morni Hills, Northern India, using high-resolution gamma-ray spectrometric analysis. It was observed that the concentration of natural radionuclides viz., 226Ra, 232Th and 40K, in the soil varies from 28.3+/-0.5 to 81.0+/-1.7Bqkg(-1), 61.2+/-1.3 to 140.3+/-2.6Bqkg(-1) and 363.4+/-4.9 to 1002.2+/-11.2Bqkg(-1) respectively. The total absorbed dose rate calculated from activity concentration of 226Ra, 232Th and 40K ranged from 71.1 to 162.0nGyh(-1). The radium equivalent (Req) and the external hazard index (Hex), which resulted from the natural radionuclides in soil, were also calculated and found to vary from 149.4 to 351.8Bqkg(-1)and from 0.40 to 0.95 respectively. These values in Upper Siwaliks area were compared with that from the adjoining areas of Punjab. The radium equivalent activities in all the soil samples were lower than the limit (370Bqkg(-1)) set in the Organization for Economic Cooperation and Development (OECD) report and the dose equivalent was within the safe limit of 1mSvy(-1).

Studying the Variation of Indoor Radon Levels in Different Dwellings in Hoshiarpur District of Punjab, India

The purpose of this study was to investigate the radon levels in different houses of different villages/towns of Hoshiarpur district of Punjab, India, using a time-integrated passive technique containing LR-115 Type II solid-state nuclear track detectors, to determine the health hazards. The measured annual average indoor radon concentrations and the annual effective dose in these houses varied from 84.93 to 128.53 Bq m−3 and 1.45 to 2.19 mSv y−1, respectively. The measured values of annual effective dose were less than the lower limit of the recommended action level (3–10 mSv). The winter to summer ratio was calculated for all the studied dwellings and this ratio varied from 0.83 to 3.14. In general, the indoor radon concentration was higher in winter season than in the summer season. The effect of ventilation conditions on measured radon levels inside dwellings was also discussed. The present indoor radon concentration values were on the higher side than the world average of 40 Bq m−3.

S-MMICF- structural and morphological modifications induced by 40 MeV C5+ ion beam on Aupolyaniline composite films

Deformations of the focusing and defocusing non-linear Schrodinger models (NLS) are considered in the context of the quasiintegrability concept. We strengthen the results of JHEP09(2012)103 for bright soliton collisions. The both (deformed) focusing and defocusing NLS’s (the defocusing case has been presented in JHEP03(2016)005, and the focusing case in JHEP05(2017)106) exhibit an infinite tower of exactly conserved charges. We show, by means of analytical and numerical methods, that for certain two-soliton (bright or dark) solutions, in which the modulus and phase of the complex modified NLS field exhibit definite parities under a space-reflection symmetry, the first four and the sequence of even order charges are exactly conserved during the scattering process of the solitons. We perform extensive numerical simulations and consider the bright solitons with focusing deformed potential . In defocusing case we consider the cubic-quintic, and saturable , potentials. However, for two-soliton field components without definite parity we also show numerically the vanishing of the first non-trivial anomaly and the exact conservation of the relevant charge. So, the parity symmetry seems to be a sufficient but not a necessary condition for the existence of the infinite tower of conserved charges in the both type of models. The model supports elastic scattering of solitons for a wide range of values of the amplitudes and velocities and the deformation parameter . Since the NLS equation is ubiquitous, our results may find potential applications in several areas of non-linear science.

Raman spectral study of electrochemically synthesized aupolyaniline composite

In this report, a two step electrochemical synthesis of Au-polyaniline composite is explored. In the first step polyaniline film was deposited on the ITO coated glass substrate by using chronopotentiometery technique. Later, using CV the surface of as prepared film was decorated by Au particles to fabricate Au-polyaniline composite. The composite is characterized by Raman spectroscopy, XRD and SEM. The SEM analysis shows a uniform dispersion of Au particles on the porous polyaniline film. A Raman spectrum confirms the existence of polyaniline in different oxidation states, which are attributed to specific signatures of delocalized charge carriers. XRD spectra confirmed Braggs reflection at various planes.

Raman and AFM study of gamma irradiated plastic bottle sheets

In this investigation, the effects of gamma irradiation on the structural properties of plastic bottle sheet are studied. The Plastic sheets were exposed with 1.25MeV 60Co gamma rays source at various dose levels within the range from 0-670 kGy. The induced modifications were followed by micro-Raman and atomic force microscopy (AFM). The Raman spectrum shows the decrease in Raman intensity and formation of unsaturated bonds with an increase in the gamma dose. AFM image displays rough surface morphology after irradiation. The detailed Raman analysis of plastic bottle sheets is presented here, and the results are correlated with the AFM observations.

120 MeV Ni Ion Beam Induced Modifications in Poly (ethylene terephthalate) Used in Commercial Bottled Water

We report the effects of heavy ion irradiation on the optical, structural, and chemical properties of polyethylene terephthalate (PET) film used in commercial bottled water. PET bottles were exposed with 120 MeV Ni ions at fluences varying from 3 × 1010 to 3 × 1012 ion/cm2. The modifications so induced were analyzed by using UV-Vis, X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. Substantial decrease in optical band gap is observed with the increase in ion fluence. In the FTIR spectra, most of bands are decreased due the degradation of the molecular structure. XRD measurements show the decrease in peak intensity, which reflects the loss of crystallinity after irradiation.

Assessment of radiation dose due to natural radionuclides in various cement samples

Samples of Ordinary Portland Cement (OPC) and Portland Pozzolana Cement (PPC) from five companies were analysed for the measurement of 226 Ra, 232 Th and 40 K using a HPGe detector based on high-resolution gamma spectrometry system. The measured activity in the selected OPC cement samples varies from 19.24 Bq kg −1 (JK Laxmi) to 40.73 Bq kg −1 (JayPee), 29.49 Bq kg −1 (JK Laxmi) to 42.17 Bq kg −1 (JayPee) and 228.25 Bq kg −1 (JK Cement) to 304.98 Bq kg −1 (Binani) for 226 Ra, 232 Th and 40 K, respectively. The concentration of radium, thorium and potassium in the selected PPC cement samples varies from 22.50 Bq kg −1 (JK Laxmi) to 48.83 Bq kg −1 (Binani), 30.74 Bq kg −1 (JK Laxmi) to 70.48 Bq kg −1 (Binani) and 267.94 Bq kg −1 (Binani) to 328.88 Bq kg −1 (JayPee), respectively. Radium equivalent, annual effective dose, absorbed dose and hazard indices were also calculated for the measured samples.