[Show abstract][Hide abstract] ABSTRACT: In the present work, attempts have been made to investigate the modification in particle track etching response of polyallyl
diglycol carbonate (PADC) due to impact of 2 MeV electrons. PADC samples pre-irradiated to 1, 10, 20, 40, 60, 80 and 100 Mrad
doses of 2 MeV electrons were further exposed to 140 MeV28 Si beam and dose-dependent track registration properties of PADC have been studied. Etch-rate values of the PADC irradiated
to 100 Mrad dose electron was found to increase by nearly 4 times that of pristine PADC. The electron irradiation has promoted
chain scissioning in PADC, thereby converting the polymer into an easily etchable polymer. Moreover, the etching response
and the detection efficiency were found to improve by electron irradiation. Scanning electron microscopy of etched samples
further revealed the surface damage in these irradiated PADCs.
[Show abstract][Hide abstract] ABSTRACT: The indoor radon level in terms of equilibrium equivalent concentration (EEC) has been measured for dwellings in the Rajshahi region of Bangladesh as well as its adjoining Chuadanga region. The data were obtained using the passive time integrated method employing LR-115 (Type II) solid state nuclear track detectors. The geometric mean value for the EEC in the dwellings located in the Rajshahi region was obtained as and for the dwellings in the Chuadanga region was obtained as . The data obtained in the present work are compared with indoor radon levels prescribed by the International Commission on Radiation Protection.
Full-text · Article · Jun 2001 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: Heavy ion induced modification in optical absorption studies of the polymers Polypropylene and Polyimide have been carried out to investigate the potential for improvements in their conductivity properties. The polymers were irradiated to four different doses of 140 MeV 28Si and 100 MeV 58Ni ion beams. The optical absorption studies were carried out by UV-Vis spectroscopy. The shift in the absorption edges were correlated to the optical band-gap by Tauc's expression. A decrease in optical band-gap has been observed in the irradiated polymers, but the effect of 58Ni ions were more pronounced in decreasing the band-gap in the polymers.
Full-text · Article · Apr 2001 · Radiation Effects and Defects in Solids
[Show abstract][Hide abstract] ABSTRACT: It is a well-known fact that proton irradiation leads to an increase in track registration sensitivity of some polymers. In the present work, the effect of the proton beam irradiation through metal foils (gold and aluminium) on polyallyldiglycol carbonate (PADC) has been studied by track technique. An increase in sensitivity of PADC adjacent to the gold foils has been found which is attributed to the effect of ionisation by the secondary particles emitted from the metal targets due to proton bombardment.
[Show abstract][Hide abstract] ABSTRACT: It has been well recognised all over the world that inhalation of indoor radon (222Rn), thoron (220Rn) and their daughter products contribute a major fraction of total dose to human beings from all possible sources of natural radioactivity. North-eastern region being in a zone of high seismicity, the indoor radon and thoron map of the region will provide a valuable database for any study related to radon and thoron anomalies. Radon enters living area mainly through floor from subsoil and building materials, and starts accumulating in poorly ventilated dwellings. So, concentration of radon and its progeny are usually higher in indoor air than in outdoor air. In the present work, an attempt has been made to assess the levels of radon, thoron and their progeny in dwellings of a few cities in the north-eastern region of India using a passive time integrated monitoring with the help of twin chamber dosimeters having LR-115 as the detector.
No preview · Article · Feb 2001 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: Ranges and energy-loss up to 4.7 MeV/u 28Si ions in Makrofol-G polymer have been determined using a nuclear track technique. Polyallyldiglycol carbonate (CR-39) detectors were calibrated using Al degraders to determine the degraded energy of 28Si ions after passing through the different stacks of Makrofol-G placed in the staircase configuration. The mean ranges of 28Si in Makrofol-G have also been determined at different energies between 1.0 MeV/u and 4.7 MeV/u. The experimental results are discussed and compared with the theoretical values obtained from four different computer codes.
Full-text · Article · Apr 1999 · Radiation Effects and Defects in Solids
[Show abstract][Hide abstract] ABSTRACT: The experimental results on the characterization of six polymeric solids in terms of energy-loss of 20-80 MeV 12C ions in kapton, hostaphan, makrofol-N, makrofol-KG, triafol-TN and triafol-BN have been presented and compared with theoretical values obtained from three different computer codes.
No preview · Article · Jul 1998 · Indian Journal of Pure and Applied Physics
[Show abstract][Hide abstract] ABSTRACT: The effect of Gamma radiation in Polyallydiglycol carbonate (PADC) detectorrs has been studied in the dose range of 100–106 Gy. Some of the properties like bulk-etch rate, track-etch rate, activation energy for bulk and track-etching have been found out for different gamma doses from 60Co Source in PADC. The experimental results are presented and discussed.
Full-text · Article · Dec 1997 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: The mean ranges and energy-loss of different energies of 161Dy in Hostaphan and Kapton have been determined using the nuclear track technique. Calibrated detectors of PADC are used for 161Dy ions through targets of different thickness. The experimental mean ranges are compared with theoretical values derived from three different prescriptions. In another experiment the track lengths of 161Dy ions at five different energies were measured in Zn-P glass and the experimental track lengths have been compared with theoretical values obtained from three different computer codes.
No preview · Article · Dec 1997 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: A new application of nuclear track microfilters has been demonstrated by determining the critical micelle concentration (CMC) of cationic, anionic and nonionic surfactants. The lowering of CMC due to the addition of methyl red dye in Trition X-100 surfactant (in molar ratio of 1 : 100) has also been studied. The critical micelle concentrations of cetyl pyridinium chloride (CPC), sodium dodecyl sulphate (SDS) and polyoxyethylene (9,5) octylphenol (Triton X-100) surfactants are determined using polycarbonate nuclear track microfilters and these are found to be comparable with the literature values. The experimental method is described here and the results are discussed.
No preview · Article · Jan 1997 · Journal of Surface Science and Technology
[Show abstract][Hide abstract] ABSTRACT: The experimental results on the characterization of three polymeric solids in terms of energy-loss of 20–80 MeV 12C ions in Kapton, Hostaphan and Makrofol-N have been presented and compared with theoretical values.
No preview · Article · Jan 1997 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: Potential alpha energy concentration (PAEC) due to radon and its progenies has been measured in dwellings of three different cities in India; namely Allahabad (in north central region), Vishakapatnam (in south eastern region) and Shillong (in north eastern region), The measurements were carried out by a passive, time-integrated method, using LR 115 (Type II) detector in bare mode. The geometric mean of potential alpha energy concentration in dwellings of Allahabad, Vishakapatnam and Shillong has been estimated to 10.0 mWL, 3.9 mWL and 11.3 mWL, respectively. The results obtained for dwellings in these three cities are discussed in the light of exposure limits set by the International Commission on Radiological Protection (ICRP).
No preview · Article · Jan 1997 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: The mean ranges and energy-loss of different energies of 86Kr and 197Au in tantalum have been determined by using the nuclear track technique. Calibrated detectors of CR-39 are used for measuring energies of the transmitted krypton and gold ions from tantalum foils of different thickness. The experimental values of mean ranges and energy-loss of 86Kr up to 17.7 MeV/A and of 197Au up to 13.5 MeV/A have been obtained in tantalum. These values are compared with theoretical ranges derived from four different prescriptions.
No preview · Article · Jul 1996 · Radiation Measurements
[Show abstract][Hide abstract] ABSTRACT: The results have been presented for range and energy loss of 11.56 MeV/A 58Ni and 13.04 MeV/A 129Xe in Hostaphan as measured by nuclear track technique using two different irradiation geometries. The experimental ranges have been compared with the corresponding theoretical values obtained from three different computer codes (RANGE, TRIM and HB). The trends and significance of the data have been discussed.
No preview · Article · Jun 1996 · Indian Journal of Pure and Applied Physics