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A series of ultraviolet B (UVB, 280–315 nm) radiation emitting Gd doped Sr3P4O13 was synthesized using the co-precipitation method. Formation of products was confirmed by X-ray diffraction analysis, while scanning electron microscope was employed to investigate the morphology of the prepared product. The emission spectra of the prepared samples were recorded at 272 nm excitation wavelength with different Gd3+ concentrations (0.005–0.15 mol). Electron paramagnetic resonance spectra of the Gd3+ doped samples showed the substitution of Sr2+ sites by Gd3+ ions with lower symmetry at X-band frequency. Shielding parameters for all the un-doped and Gd doped Sr3P4O13 samples were determined in the range 1 keV–100 GeV photon energy. These photon interaction parameters vary with the compositions and the photon energy. These parameters were found to be maximum for the gadolinium concentration 0.15 mol. The current investigation and obtained results would be helpful for shielding evaluation of radioactive waste containment in the nuclear fuel cycle.

Gamma ray shielding effectiveness of superconductors with a high mass density has been investigated. We calculated the mass attenuation coefficients, the mean free path (mfp) and the exposure buildup factor (EBF). The gamma ray EBF was computed using the Geometric Progression (G-P) fitting method at energies 0.015-15 MeV, and for penetration depths up to 40 mfp. The fast-neutron shielding effectiveness has been characterized by the effective neutron removal cross-section of the superconductors. It is shown that CaPtSi3, CaIrSi3, and Bi2Sr2Ca1Cu2O8.2 are superior shielding materials for gamma rays and Tl0.6Rb0.4Fe1.67Se2 for fast neutrons. The present work should be useful in various applications of superconductors in fusion engineering and design. (C) 2014 Elsevier Ltd. All rights reserved.

Geant4 Monte Carlo code simulations were used to solve experimental and theoretical complications for calculation of mass energy-absorption coefficients of elements, air, and compounds. The mass energy-absorption coefficients for nuclear track detectors were computed first time using Geant4 Monte Carlo code for energy 1 keV-20 MeV. Very good agreements for simulated results of mass energy-absorption coefficients for carbon, nitrogen, silicon, sodium iodide and nuclear track detectors were observed on comparison with the values reported in the literatures. Kerma relative to air for energy 1 keV-20 MeV and energy absorption buildup factors for energy 50 keV-10 MeV up to 10 mfp penetration depths of the selected nuclear track detectors were also calculated to evaluate the absorption of the gamma photons. Geant4 simulation can be utilized for estimation of mass energy-absorption coefficients in elements and composite materials. (C) 2014 Elsevier Ltd. All rights reserved.

The mass attenuation coefficients, mu/rho and effective atomic numbers, Z(eff) of some carbon steel and stainless steel alloys have been calculated by using Geant4, MCNP simulation codes for different gamma ray energies, 279.1 keV, 661.6 keV, 662 keV, 1115.5 keV, 1173 keV and 1332 key. The simulation results of Zeff using Geant4 and MCNP codes have been compared with possible available experimental results and theoretical WinXcom, and good agreement has been observed. The simulated pip and Zeff values using Geant4 and MCNP code signifies that both the simulation process can be followed to determine the gamma ray interaction properties of the alloys for energies wherever analogous experimental results may not be available. This kind of studies can be used for various applications such as for radiation dosimetry, medical and radiation shielding. (C) 2014 Elsevier Ltd. All rights reserved.

Optically stimulated luminescence (OSL) materials are sensitive dosimetric materials used for precise and accurate dose measurement for low-energy ionizing radiation. Low dose measurement capability with improved sensitivity makes these dosimeters very useful for diagnostic imaging, personnel monitoring and environmental radiation dosimetry. Gamma ray energy absorption buildup factors and exposure build factors were computed for OSL materials using the five-parameter Geometric Progression (G-P) fitting method in the energy range 0.015–15 MeV for penetration depths up to 40 mean free path. The computed energy absorption buildup factor and exposure buildup factor values were studied as a function of penetration depth and incident photon energy. Effective atomic numbers and Kerma relative to air of the selected OSL materials and tissue equivalence were computed and compared with that of water, PMMA and ICRU standard tissues. The buildup factors and kerma relative to air were found dependent upon effective atomic numbers. Buildup factors determined in the present work should be useful in radiation dosimetry, medical diagnostics and therapy, space dosimetry, accident dosimetry and personnel monitoring.

The gel dosimeter comprises of phantom, dosimetric material and three-D spatial dose distribution has advantages over one- and two-D dosimeters. Energy absorption buildup factor (EABF) and exposure buildup factor (EBF) values of sixteen gel dosimeters have been computed for photon energy 0.015 to 15 MeV up to 40 mfp (mean free path) penetration depths. Kerma of the gel dosimeters were computed for photon energy 1 keV to 20 MeV. The water and PMMA phantom equivalence of the gel dosimeters was evaluated using EABF, and large difference was noted below 1 MeV photon energy. This study should be useful for estimation of effective dose to the human organs and simulation of the dose for radiation therapy and various medical applications.

Gamma-ray exposure buildup factor (EBF) values and neutron shielding effectiveness of bismuth borosilicate (BBS) glass systems in composition (50− x )SiO 2 :15B 2 O 3 :2Al 2 O 3 :10CaO:23Na 2 O: x Bi 2 O 3 (where x =0, 5, 10, 15 and 20 mol%) were calculated. The EBF values were computed for photon energy 0.015–15 MeV up to penetration depths of 40 mfp (mean free path) by the geometrical progression (G-P) method. The EBF values were found dependent upon incident photon energy, penetration and bismuth molar concentration. In low- and high-energy photon regions, the EBF values were minimum whereas maximum in the intermediate-energy region. The fast neutron removal cross sections for energy 2–12 MeV were calculated by the partial density method. The BBS glass with 20 mol% Bi 2 O 3 is found to be superior gamma-ray and neutron transparent shielding. The EBF values of the BBS glasses were compared with steel–magnetite concrete and lead. The investigation was carried out to explore the advantages of the BBS glasses in different radiation shielding applications.