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Kant K.,Aggarwal College | Rashmi,GFITM | Sonkawade R.G.,Inter University Accelerator Center | Chauhan R.P.,G L A Institute of Technology and Management | And 2 more authors.
Indian Journal of Pure and Applied Physics | Year: 2010

Fly ash is the by-product of burnt coal which is naturally occurring radioactive material (NORM). Because of human activity and its use in manufacturing of bricks, sheets, cement, land filling etc may present a radiation hazard to people and the environment Thus, it is very important to carry out radioactivity measurements in fly ash from the health and hygiene point of view In the present study, the activity concentrations of 238U, 232Th and 40K have been varied from 99 ± 2 to 203 ± 4 Bq/kg, 145 ± 2 to 288 ± 4 Bq/kg, and 355 ± 5 to 516 ± 6 Bq/kg, respectively in various fly ash samples The radium equivalent activity was varied from 317 to 614 Bq/kg, radon activity varied from 214 to 590 Bq/m3, radon exhalation rate varied from 7.8 to 21.6 mBqkg-1h-1 for mass exhalation rate and from 138 to 381 mBqm-2h-1 for surface exhalation rate in the fly ash samples used in the present investigation The absorbed dose varied from 143 to 277 nGyh-1, the indoor annual effective dose varied from 0.70 to 1.36 mSv and the outdoor annual effective dose varied from 0.17 to 0.34 mSv In all the samples, the activity concentration of 238U, 232Th and 40K was found to be below the permissible levels A strong positive correlation has been observed between uranium concentration, radon activity and radon exhalation rate.

Kant K.,Aggarwal College | Rashmi,GFITM | Sharma G.S.,Gla Institute Of Technology And Management
Indian Journal of Pure and Applied Physics | Year: 2010

Radon activity in slate mines in the aravali range in Haryana was measured to protect the occupational workers and general public from radiation. The alpha sensitive LR-115 type II plastic track detectors (solid state nuclear track detectors) were used for the measurements. Results of various measurements of the radon activity and inhalation dose received by the workers have been reported. The radon activity and the annual inhalation dose in the environment of various slate stone mines in Haryana varied from 21 to 113 Bq m -3 with an average of 38.5 ± 5.8 Bq m -3 and 0.37 to 1.94 mSv with an average of 0.66 ± 0.10 mSv, respectively. Seasonal variation of radon activity has also been studied and reported.

Kumar V.,Sant Longowal Institute of Engineering And Technology | Sonkawade R.G.,Inter University Accelerator Center | Chakarvarti S.K.,National Institute of Technology Kurukshetra | Kulriya P.,Inter University Accelerator Center | And 3 more authors.
Vacuum | Year: 2011

We have investigated neutron irradiation effects on the optical, structural and chemical properties of polyallyl diglycol carbonate (PADC) polymer, commercially named as CR-39. For this purpose, PADC samples were exposed with 4 MeV Am-Be neutron source at fluences varying from 2.36 × 106 to 5.94 × 107 n/cm2. The modifications so induced were analyzed using UV-Visible spectroscopy, X-ray diffraction Measurement (XRD), Photoluminescence (PL) and Fourier Transform infrared (FTIR) spectroscopy in the total attenuation reflection (ATR) mode. UV-Vis spectra of pristine and neutron irradiated PADC polymer sheets exhibit a decreasing trend in optical band gap. This decline in optical band gap with increasing fluence has been discussed on the basis of neutron irradiation induced defects in PADC. The XRD pattern of PADC shows the decreasing intensity of peak positions with increasing in fluence, which suggest that semicrystallinity of PADC changes slightly to amorphous phase after irradiation. At low fluence, crystallinity was found to increase but at higher fluence, it decreased which could be ascribed to neutron- induced defects in the polymer samples. Crystallite size calculated using Scherrer formula indicates a change and reflects the formation of disordered system in the irradiated polymer samples. The PL spectra show that the intensity of PL peak decreased with increase in fluence, which may be due to the disordered system via creation of defects in the irradiated polymer. The FTIR spectrum shows an overall reduction in intensity of the typical bands, indicating the degradation of PADC polymer after irradiation. These results so obtained can be used successfully in dosimetery using well reported protocols. © 2011 Elsevier Ltd. All rights reserved.

Gupta S.K.,Guru Gobind Singh Indraprastha University | Gupta S.K.,Aggarwal College | Singh P.,Guru Gobind Singh Indraprastha University | Singh R.,Guru Nanak Dev University | Kumar R.,Guru Gobind Singh Indraprastha University
Advances in Polymer Technology | Year: 2015

The present work focuses on the effects of two different ions (70 MeV carbon and 50 MeV lithium) and gamma radiation upon the structural, optical, and chemical properties of 125-μm thick polypropylene (PP) polymer films. The different samples of PP were irradiated with ions to the fluences in the range 1011-1013 ions/cm2 and exposed to gamma radiation of doses in the range 100-1250 kGy. A comparative study is carried out upon different parameters of irradiated polymer samples such as crystallite size and band gap energy. The structural properties are effectively modified by the ions irradiation, whereas gamma exposure shows insignificant changes in this regard; however, gamma exposure is observed to be effective in gradually decreasing the band gap energy of the PP samples with an increase in the gamma dose. The formation of new chemical bands is observed in the ion-irradiated and gamma-exposed PP polymer samples. © 2015 Wiley Periodicals, Inc.

Dhillon R.K.,Guru Nanak Dev University | Singh P.,Guru Gobind Singh Indraprastha University | Gupta S.K.,Guru Gobind Singh Indraprastha University | Gupta S.K.,Aggarwal College | And 2 more authors.
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2013

The optical and structural response of low density polyethylene (LDPE) under the influence of 80 MeV N6+ ion at various fluences (5 × 1011 to 1 × 1013 ions/cm2) and gamma rays at doses 100 and 1000 kGy were studied using UV-Vis spectroscopy and X-ray diffraction (XRD). The optical absorption spectra of N6+ ion irradiated LDPE showed a shift in the absorption edge towards higher wavelength side, which indicated a significant decrease in the direct and indirect band gaps of the films. The optical data showed decrease in the calculated band gap with increasing gamma dose. The diffraction pattern of pristine sample showed the semi crystalline nature of the polymer. The decrease in peak intensity and hence increase in amorphous nature was observed in N6+ ion irradiated samples. The opposite behavior is seen in case of gamma ray exposed samples at 100 kGy dose. The crystallite size (L) decreased but the other factors like interchain separation (R), interplanar distance (d), micro strain (ε), dislocation density (δ) and distortion parameters (g) increased for N 6+ ion irradiated samples. © 2013 Elsevier B.V. All rights reserved.

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