International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1990
The present work describes the experimental measurement of the total etchable range for different... more The present work describes the experimental measurement of the total etchable range for different heavy ions, ':C (8.7 MeV/N), ':O (8.7 MeV/N). :gNe (7.7 MeV/N), $i (6.4 MeV/N), $Fe (6.4 MeV/N) and i:Ni (6.5 MeViN) in CR-39 (Dop) and Lexan polycarbonate plastic track detectors. The energy loss rate dE/dX and the range, R of these heavy ions in these detectors have also been computed theoretically using the Mukherjee and Nayak (Nucl. Instrum. Methods 159, 421; 1979) and Benton and Henke (Nucl. Instrum. Methods 67, 87; 1969) methods. A comparative study indicates that the experimental values of the total etchable range agree well with the corresponding theoretically computed values of the total range using the Mukherjee and Nayak method. However, the results indicate a disagreement with calculations using the Benton and Henke method. An attempt has also been made to develop empirical relations between the energy loss rate, dE/dX (calculated by using the Mukherjee and Nayak stopping power equations), the corresponding energy E, and the nuclear charge Z for different heavy ions traversing CR-39 (Dop) and Lexan polycarbonate plastic track detectors. The energy loss rate, dE/dX calculated from the Mukherjee and Nayak stopping power equations and the corresponding values predicted from empirical relations have been found to be in close agreement.
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1988
Samples of phosphate glass detectors have been exposed vertically to 28Si (6.4 MeV/N), 40Ar (5.5.... more Samples of phosphate glass detectors have been exposed vertically to 28Si (6.4 MeV/N), 40Ar (5.5. 3.75 and 2.55 MeV/N), S6Fe (6.4 MeV/N), S9Ni (6.5 MeV/N), WKr (0.9 MeV/N) and "'Xe (0.9 MeV/N) ions from heavy ion accelerators at the Joint Institute of Nuclear Research (JINR), Dubna (Moscow), U.S.S.R. The exposed samples have been etched in 40 ~01% HF and also in NaOH solution of varying concentrations (l-6N) at 40°C for different etching times. Track diameter variations against the dissolved detector thickness have been studied. The total etchable track length for these heavy ions in this detector has been determined experimentally. The energy loss rate and the range of the heavy ions in this detector have also been computed theoretically. Comparing the total etchable track length with the theoretical range, the critical threshold for etchable track formation has been determined.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006
Measurements of energy loss straggling for Li, C and O ions in varying thicknesses of mylar (C 10... more Measurements of energy loss straggling for Li, C and O ions in varying thicknesses of mylar (C 10 H 8 O 4) and polycarbonate (C 16 H 14 O 3) absorber foils in the energy range $3.0-6.0 MeV/u have been carried out, utilizing the Pelletron accelerator facility at Nuclear Science Centre, New Delhi, India. These measured values have been compared with the calculated values in order to establish the validity of various energy loss straggling formulations viz. Bohr, Lindhard and Scharff and Bethe-Livingston. From the energy loss straggling measurements in these two polymers having same atomic constituents and almost same effective Z, the validity of Bragg's rule has been checked.
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1987
Pre-annealed and pre-etched samples of soda glass detectors have been exposed vertically to $Ar, ... more Pre-annealed and pre-etched samples of soda glass detectors have been exposed vertically to $Ar, ZFe, 59Ni, i:Kr and 'Exe ion beams of various energies at the Joint Institute of Nuclear Research(JINR) Dubna YM oscow) U.S.S.R. The exposed samples were etched in the new etchant (HF 48 ~01% + H,SO, 96 ~01% + H,O in the ratio of 6: 1 : 18 with a small amount of Zn) at 40°C. The variation of etchpit diameter against etching time has been studied and the total etchable range for different heavy ions in this detector has been determined. The energy loss rate and range of the heavy ions in this detector have been computed theoretically. Finally, the response of the detector to the heavy ions and the relationship between the etch rate ratio and the corresponding energy loss rate have been studied.
ABSTRACT Polyethylene terephthalate (PET) samples have been implanted to 100 keV Kr+ ions at the ... more ABSTRACT Polyethylene terephthalate (PET) samples have been implanted to 100 keV Kr+ ions at the fluences 1×1015-- 1×1016 cm-2. From I-V characteristics, the conduction mechanism was found to be shifted from ohmic to space charge limited conduction (SCLC) after implantation. The surface conductivity of these implanted samples was found to increase with increasing implantation dose. The structural alterations in the Raman spectra of implanted PET samples indicate that such an increase in the conductivity may be attributed to the formation of conjugated double bonded carbonaceous structure in the implanted layer of PET.
Nuclear Instruments and Methods in Physics Research, 1984
Samples of cellulose nitrate Daicel (Japanese) and cellulose nitrate (Russian) have been exposed ... more Samples of cellulose nitrate Daicel (Japanese) and cellulose nitrate (Russian) have been exposed to 4°Ar ions of energy 7.4. MeV/N and 5°Ti ions of energy 4.9 MeV/N respectively at an angle of 30 ° from the detector surface using heavy ion cyclotron facilities at JINR Dubna (Moscow), USSR. These samples have been etched in 6.25N NaOH at 60°C. The bulk etch rate V h has been found at different etching temperatures to determine the activation energies for bulk etching for these plastics. The variation of track length against etching time has been studied to find out the values of total etchable track length for these ions in these detectors. The energy loss and ranges of these ions in these plastics have been computed theoretically. By the comparison of the total etchable track length with the respective value of the theoretically computed range, the values of the critical threshold for these plastics have been found. Finally an attempt has been made to compare the response of these two plastics.
PMMA-PAni composite films have been prepared by mixing different wt.% of chemically synthesized P... more PMMA-PAni composite films have been prepared by mixing different wt.% of chemically synthesized PAni-DBSA in PMMA by sol-gel method. Effect of blending of PAni with PMMA on the structural and dielectric properties of PMMA has been analysed. Raman analysis confirms the formation of chemical network in PMMA and PAni functional groups. An increase in ac conductivity and decrease in dielectric constant were observed with increase in concentration of PAni in PMMA. The dielectric relaxation time reduces from 8.70 s (in pure PMMA) to 2.30 s after embedding PAni by 10 wt.% corroborating towards the enhanced conducting nature of blends.
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 1982
... as of bridging nitric oxide in the complexes. * Address for correspondence - Sumer %gar behin... more ... as of bridging nitric oxide in the complexes. * Address for correspondence - Sumer %gar behind Vijay Cinema, Uolghar, (iorakhpur-273001 (UP)INDIA. 287 ... SENGUPTA AND KUMAR 1. C. Preti and G. Tosi, Aust. ... 6. BK Sinha, R. Singh, JP Srivastava and LK MiPhra, J.Inorg. ...
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 1982
The reactions of bis-π-cyclopentadienyl and bis-π-indenyl molybdenum(VI)-oxodichloride with biden... more The reactions of bis-π-cyclopentadienyl and bis-π-indenyl molybdenum(VI)-oxodichloride with bidentate thio-Schiff bases (TSH), derived by the condensation of S-methyldithiocarbazate with benzaldehyde, acetophenone, benzophenone, and with tridentate thio-Schiff bases (TŚH2), derived by the condensation of S-methyldithiocarbazate and salicyladehyde, 2-hydroxy-1-naphthaldehyde, 2-hydroxy acetophenone, have been studied. The isolated products of the types [R2MoO(TS)C1] and [R2MoO(TS′)] (R = π -C5H5 and π-C9H7) have been characterized by their elemental analyses, electrical conductance and magnetic susceptibility measurements and spectral data (infrared and electronic).
LSS based computed electronic stopping power values have been compared with the corresponding mea... more LSS based computed electronic stopping power values have been compared with the corresponding measured values in polymers for heavy ions with Z ¼ 5-29, in the reduced ion velocity region, v red 1. Except for limited v red w 0.6-0.85, the formulation generally shows significantly large deviations with the measured values. The z factor, which was approximated to be wZ 1 1/6 , involved in LSS theory has been suitably modified in the light of the available experimental stopping power data. The calculated stopping power values after incorporating modified z in LSS formula have been found to be in close agreement with measured values in various polymers in the reduced ion velocity range 0.35 v red 1.0.
The samples of CR-39(DOP) and SR-90 polymer track detectors have been exposed to-particles from 2... more The samples of CR-39(DOP) and SR-90 polymer track detectors have been exposed to-particles from 241 Am source in an exposure unit. The temperature of the detectors during irradiation has been varied from ∼ − 30 • C to 70 • C. These exposed samples have been etched in 6:25 N NaOH solution at 60 • C for various etching times. The variation of sensitivity of these detectors as a function of registration temperature has been studied. It has been observed that at the ÿxed registration temperature, the sensitivity of SR-90 is more than CR-39(DOP) polymer track detector. However, the enhancement in sensitivity with the decrease in registration temperature is more pronounced in case of CR-39(DOP) than SR-90.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
The range of several heavy ions as 238 U, 208 Pb, 197 Au, 139 La, 58 Ni and 56 Fe in sodalime gla... more The range of several heavy ions as 238 U, 208 Pb, 197 Au, 139 La, 58 Ni and 56 Fe in sodalime glass; 197 Au and 58 Ni in muscovite mica and Lexan polycarbonate; 209 Bi and 197 Au in CR-39 have been determined experimentally. The calculations of range for these projectile±target combinations have been made using the Benton and Henke [10], Mukherjee and Nayak [11], Ziegler et al. [12] and Hubert et al. [14] semiempirical formulations. Finally a comparison has been made with the experimental results.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
The stopping powers of Mylar for several heavy ions covering Z=11 to 29 in the energy range 0.3 t... more The stopping powers of Mylar for several heavy ions covering Z=11 to 29 in the energy range 0.3 to 2.3 MeV/n have been measured using the elastic recoil detection technique and twin detector system. The technique provided a unique method to generate a variety of variable energy ...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2002
... In order to record the energy spectra of recoil ions without and with absorber foil simultane... more ... In order to record the energy spectra of recoil ions without and with absorber foil simultaneously to minimize the experimental error, a specially designed twin detectormount has been used in the present experiment. In twin ...
MeV/n). It has been observed that the Hubert et al. formulation provides results in best agreemen... more MeV/n). It has been observed that the Hubert et al. formulation provides results in best agreement with the experimental results for all projectile and target combinations in this energy domain.
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1990
The present work describes the experimental measurement of the total etchable range for different... more The present work describes the experimental measurement of the total etchable range for different heavy ions, ':C (8.7 MeV/N), ':O (8.7 MeV/N). :gNe (7.7 MeV/N), $i (6.4 MeV/N), $Fe (6.4 MeV/N) and i:Ni (6.5 MeViN) in CR-39 (Dop) and Lexan polycarbonate plastic track detectors. The energy loss rate dE/dX and the range, R of these heavy ions in these detectors have also been computed theoretically using the Mukherjee and Nayak (Nucl. Instrum. Methods 159, 421; 1979) and Benton and Henke (Nucl. Instrum. Methods 67, 87; 1969) methods. A comparative study indicates that the experimental values of the total etchable range agree well with the corresponding theoretically computed values of the total range using the Mukherjee and Nayak method. However, the results indicate a disagreement with calculations using the Benton and Henke method. An attempt has also been made to develop empirical relations between the energy loss rate, dE/dX (calculated by using the Mukherjee and Nayak stopping power equations), the corresponding energy E, and the nuclear charge Z for different heavy ions traversing CR-39 (Dop) and Lexan polycarbonate plastic track detectors. The energy loss rate, dE/dX calculated from the Mukherjee and Nayak stopping power equations and the corresponding values predicted from empirical relations have been found to be in close agreement.
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1988
Samples of phosphate glass detectors have been exposed vertically to 28Si (6.4 MeV/N), 40Ar (5.5.... more Samples of phosphate glass detectors have been exposed vertically to 28Si (6.4 MeV/N), 40Ar (5.5. 3.75 and 2.55 MeV/N), S6Fe (6.4 MeV/N), S9Ni (6.5 MeV/N), WKr (0.9 MeV/N) and "'Xe (0.9 MeV/N) ions from heavy ion accelerators at the Joint Institute of Nuclear Research (JINR), Dubna (Moscow), U.S.S.R. The exposed samples have been etched in 40 ~01% HF and also in NaOH solution of varying concentrations (l-6N) at 40°C for different etching times. Track diameter variations against the dissolved detector thickness have been studied. The total etchable track length for these heavy ions in this detector has been determined experimentally. The energy loss rate and the range of the heavy ions in this detector have also been computed theoretically. Comparing the total etchable track length with the theoretical range, the critical threshold for etchable track formation has been determined.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006
Measurements of energy loss straggling for Li, C and O ions in varying thicknesses of mylar (C 10... more Measurements of energy loss straggling for Li, C and O ions in varying thicknesses of mylar (C 10 H 8 O 4) and polycarbonate (C 16 H 14 O 3) absorber foils in the energy range $3.0-6.0 MeV/u have been carried out, utilizing the Pelletron accelerator facility at Nuclear Science Centre, New Delhi, India. These measured values have been compared with the calculated values in order to establish the validity of various energy loss straggling formulations viz. Bohr, Lindhard and Scharff and Bethe-Livingston. From the energy loss straggling measurements in these two polymers having same atomic constituents and almost same effective Z, the validity of Bragg's rule has been checked.
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1987
Pre-annealed and pre-etched samples of soda glass detectors have been exposed vertically to $Ar, ... more Pre-annealed and pre-etched samples of soda glass detectors have been exposed vertically to $Ar, ZFe, 59Ni, i:Kr and 'Exe ion beams of various energies at the Joint Institute of Nuclear Research(JINR) Dubna YM oscow) U.S.S.R. The exposed samples were etched in the new etchant (HF 48 ~01% + H,SO, 96 ~01% + H,O in the ratio of 6: 1 : 18 with a small amount of Zn) at 40°C. The variation of etchpit diameter against etching time has been studied and the total etchable range for different heavy ions in this detector has been determined. The energy loss rate and range of the heavy ions in this detector have been computed theoretically. Finally, the response of the detector to the heavy ions and the relationship between the etch rate ratio and the corresponding energy loss rate have been studied.
ABSTRACT Polyethylene terephthalate (PET) samples have been implanted to 100 keV Kr+ ions at the ... more ABSTRACT Polyethylene terephthalate (PET) samples have been implanted to 100 keV Kr+ ions at the fluences 1×1015-- 1×1016 cm-2. From I-V characteristics, the conduction mechanism was found to be shifted from ohmic to space charge limited conduction (SCLC) after implantation. The surface conductivity of these implanted samples was found to increase with increasing implantation dose. The structural alterations in the Raman spectra of implanted PET samples indicate that such an increase in the conductivity may be attributed to the formation of conjugated double bonded carbonaceous structure in the implanted layer of PET.
Nuclear Instruments and Methods in Physics Research, 1984
Samples of cellulose nitrate Daicel (Japanese) and cellulose nitrate (Russian) have been exposed ... more Samples of cellulose nitrate Daicel (Japanese) and cellulose nitrate (Russian) have been exposed to 4°Ar ions of energy 7.4. MeV/N and 5°Ti ions of energy 4.9 MeV/N respectively at an angle of 30 ° from the detector surface using heavy ion cyclotron facilities at JINR Dubna (Moscow), USSR. These samples have been etched in 6.25N NaOH at 60°C. The bulk etch rate V h has been found at different etching temperatures to determine the activation energies for bulk etching for these plastics. The variation of track length against etching time has been studied to find out the values of total etchable track length for these ions in these detectors. The energy loss and ranges of these ions in these plastics have been computed theoretically. By the comparison of the total etchable track length with the respective value of the theoretically computed range, the values of the critical threshold for these plastics have been found. Finally an attempt has been made to compare the response of these two plastics.
PMMA-PAni composite films have been prepared by mixing different wt.% of chemically synthesized P... more PMMA-PAni composite films have been prepared by mixing different wt.% of chemically synthesized PAni-DBSA in PMMA by sol-gel method. Effect of blending of PAni with PMMA on the structural and dielectric properties of PMMA has been analysed. Raman analysis confirms the formation of chemical network in PMMA and PAni functional groups. An increase in ac conductivity and decrease in dielectric constant were observed with increase in concentration of PAni in PMMA. The dielectric relaxation time reduces from 8.70 s (in pure PMMA) to 2.30 s after embedding PAni by 10 wt.% corroborating towards the enhanced conducting nature of blends.
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 1982
... as of bridging nitric oxide in the complexes. * Address for correspondence - Sumer %gar behin... more ... as of bridging nitric oxide in the complexes. * Address for correspondence - Sumer %gar behind Vijay Cinema, Uolghar, (iorakhpur-273001 (UP)INDIA. 287 ... SENGUPTA AND KUMAR 1. C. Preti and G. Tosi, Aust. ... 6. BK Sinha, R. Singh, JP Srivastava and LK MiPhra, J.Inorg. ...
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 1982
The reactions of bis-π-cyclopentadienyl and bis-π-indenyl molybdenum(VI)-oxodichloride with biden... more The reactions of bis-π-cyclopentadienyl and bis-π-indenyl molybdenum(VI)-oxodichloride with bidentate thio-Schiff bases (TSH), derived by the condensation of S-methyldithiocarbazate with benzaldehyde, acetophenone, benzophenone, and with tridentate thio-Schiff bases (TŚH2), derived by the condensation of S-methyldithiocarbazate and salicyladehyde, 2-hydroxy-1-naphthaldehyde, 2-hydroxy acetophenone, have been studied. The isolated products of the types [R2MoO(TS)C1] and [R2MoO(TS′)] (R = π -C5H5 and π-C9H7) have been characterized by their elemental analyses, electrical conductance and magnetic susceptibility measurements and spectral data (infrared and electronic).
LSS based computed electronic stopping power values have been compared with the corresponding mea... more LSS based computed electronic stopping power values have been compared with the corresponding measured values in polymers for heavy ions with Z ¼ 5-29, in the reduced ion velocity region, v red 1. Except for limited v red w 0.6-0.85, the formulation generally shows significantly large deviations with the measured values. The z factor, which was approximated to be wZ 1 1/6 , involved in LSS theory has been suitably modified in the light of the available experimental stopping power data. The calculated stopping power values after incorporating modified z in LSS formula have been found to be in close agreement with measured values in various polymers in the reduced ion velocity range 0.35 v red 1.0.
The samples of CR-39(DOP) and SR-90 polymer track detectors have been exposed to-particles from 2... more The samples of CR-39(DOP) and SR-90 polymer track detectors have been exposed to-particles from 241 Am source in an exposure unit. The temperature of the detectors during irradiation has been varied from ∼ − 30 • C to 70 • C. These exposed samples have been etched in 6:25 N NaOH solution at 60 • C for various etching times. The variation of sensitivity of these detectors as a function of registration temperature has been studied. It has been observed that at the ÿxed registration temperature, the sensitivity of SR-90 is more than CR-39(DOP) polymer track detector. However, the enhancement in sensitivity with the decrease in registration temperature is more pronounced in case of CR-39(DOP) than SR-90.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
The range of several heavy ions as 238 U, 208 Pb, 197 Au, 139 La, 58 Ni and 56 Fe in sodalime gla... more The range of several heavy ions as 238 U, 208 Pb, 197 Au, 139 La, 58 Ni and 56 Fe in sodalime glass; 197 Au and 58 Ni in muscovite mica and Lexan polycarbonate; 209 Bi and 197 Au in CR-39 have been determined experimentally. The calculations of range for these projectile±target combinations have been made using the Benton and Henke [10], Mukherjee and Nayak [11], Ziegler et al. [12] and Hubert et al. [14] semiempirical formulations. Finally a comparison has been made with the experimental results.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
The stopping powers of Mylar for several heavy ions covering Z=11 to 29 in the energy range 0.3 t... more The stopping powers of Mylar for several heavy ions covering Z=11 to 29 in the energy range 0.3 to 2.3 MeV/n have been measured using the elastic recoil detection technique and twin detector system. The technique provided a unique method to generate a variety of variable energy ...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2002
... In order to record the energy spectra of recoil ions without and with absorber foil simultane... more ... In order to record the energy spectra of recoil ions without and with absorber foil simultaneously to minimize the experimental error, a specially designed twin detectormount has been used in the present experiment. In twin ...
MeV/n). It has been observed that the Hubert et al. formulation provides results in best agreemen... more MeV/n). It has been observed that the Hubert et al. formulation provides results in best agreement with the experimental results for all projectile and target combinations in this energy domain.
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