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Using the sol–gel process, a series of Sr2-xZnSi2O7:xGd (0.01 ≤ x≤0.11) samples was fabricated. Their crystal characteristics, surface morphologies, and spectral characteristics were analyzed using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectroscopy. Upon 272-nm excitation, a prominent emission band appeared at 313 nm (6P7/2 → 8S7/2) in all the samples. The electron paramagnetic resonance (EPR) and PL analyses confirmed the presence of Gd3+ in the Sr2ZnSi2O7 structure, where the Gd3+ ions occupied distorted Sr2+ sites in the host lattice. Additionally, three photon interaction parameters, namely the mass attenuation coefficient, effective atomic number, and effective electron density, were calculated within the 1 keV–100 GeV photon energy range for all the samples. These photon interaction parameters varied widely over the studied energy range. Particularly, the shielding effectiveness increased with increasing gadolinium concentration. These interaction parameters will be very useful for shielding applications against gamma-rays.

This work aimed to investigate the mechanical features and radiation shielding properties of (100–2x)TeO2+xAg2O + xWO3 (where x = 7.5, 15, 22.5, and 30 mol%) glass system. Based on Makishima–Mackenzie's theory, the basic mechanical features such as packing density, Poisson's ratio, elastic moduli, hardness, and fractal bond connectivity were studied. The shielding investigations included the radiations of gamma, electron, neutron, and heavy charged particles. Geant4 toolkit and newly developed Phy-X program were employed to evaluate mass attenuation coefficient (μ/ρ), transmission factors (HVL and MFP), exposure buildup factor (EBF) and effective atomic number (Zeff) of gamma and charged particles for the studied glasses. Neutron shielding investigation was examined by determining neutron removal cross section (NRCS) of the glasses involved. The results showed that Ag2O and WO3 contents had an insignificant effect on the mechanical properties of the investigated glass system. In contrast, the Ag2O and WO3 contents had a significant effect on the shielding capacity of the glasses against gamma radiation and charged particles. The Zeff values were in the range of 24–60 for gamma, 24–31 for electron, 18–24 for proton, 15–23 for alpha, and 13–19 for carbon ion. The shielding properties of these glasses were compared with those of commonly used shields. The investigated glass system can be used in shielding applications, wherein Ag2O and WO3 contents can be balanced with the TeO2 content according to the type and energy of the radiation.

A mini subcritical nuclear reactor was designed using Monte Carlo methods. The reactor has light water as moderator, natural uranium as fuel, and a 239PuBe neutron source. In the design uranium fuel was modeled in an arrangement of concentric rings: 8.5, 14.5, 20.5 26.5, 32.5 cm-inner radius, 3 cm-thick, and 36 cm-high. Different models were made from a single ring of natural uranium to five rings. For each case, the neutron spectra, the neutron fluence distribution, the effective multiplication factor, the amplification factor, and the reactor power were estimated. The ambient dose equivalent rate outside the mini reactor was also estimated. The maximum value for the keff (0.78) was obtained when five rings of fuel were used; this value is close to 0.86 which belongs to a Nuclear Chicago subcritical reactor which requires almost twice the amount of uranium than the mini subcritical reactor.

This paper examines the gamma-ray shielding features of some selected tellurite-based glasses in the form of xMoO3(100−x)TeO2 (20 ≤ x ≤ 50 mol%). Mass attenuation coefficients (μ m ) of these glasses have been calculated using Geant4 toolkit and XCOM program for photon energy range of 1 keV—1000 MeV. The correlation factor (R2) between these two methods was found to be almost one. Shielding effectiveness for these glasses has been estimated by computing half value layer (HVL), effective atomic number (Z eff ), and mean free paths (MFP). It was noticed that the heavy metal oxide of TeO2 plays an important role in improving the shielding effectiveness of the glasses. The Mo20Te80 glass has shown the promising properties to serve for gamma ray protection applications as compared with many conventional concretes and other newly developed glasses.

The mass attenuation coefficients of seven different types of normal and heavy concretes like ordinary, hematite-serpentine, ilmenite-limonite, basalt-magnetite, ilmenite, steel-scrap and steel-magnetite concretes has been simulated using FLUKA Monte Carlo code at high energies 1.5, 2, 3, 4, 5 and 6 MeV. The mass attenuation coefficients and linear attenuation coefficient of the concretes were found dependent upon the chemical composition, density and gamma ray energy. FLUKA Monte Carlo code results were found in good agreement with experimental and theoretical XCOM data. Our investigations for high energy gamma-ray interaction validate the FLUKA Monte Carlo code for use where experimental gamma-ray interaction results are not available.

A series of ternary phosphate glasses in the form of (PbO)x(ZnO)60-x(P2O5)40 where x = 0–60 mol%, have been successfully prepared by conventional melt-quenching technique. The physical and elastic properties of the glasses have been investigated using pulse echo technique. The longitudinal and shear velocity of the glasses were measured using the MBS8000 ultrasonic data acquisition system at 10 MHz frequency in room temperature. The density, ultrasonic velocity and elastic moduli are found to be composition dependent and the correlation between the elastic moduli with the atomic packing density is discussed in detailed. The shielding parameters, mass attenuation coefficients, half value layers and exposure buildup factor (EBF) values have been computed using WinXCom program with the use of GP fitting method, and variation of shielding parameters are discussed for the effect of PbO addition into the glasses and photon energy. An increase in the density of the glasses results in a change in crosslink density. The sound velocity and elastic properties increased with PbO content and increase in Poisson's ratio trend suggests that the rigidity of the glasses has decreased. Besides, the replacement of ZnO by PbO causes an increase in mass attenuation coefficient, while the half value layer and the exposure buildup factor were decreased and these glasses has been potentially used as shielding material.

Gamma ray exposure buildup factor (EBF) and neutron shielding efficiency of borate glass systems in composition (100 − x − y) Na2B4O7−xPbO−yNiO (where x and y = 0, 2, 4, 6, 8 and 10 weight percentage) were investigated in the present study. Gamma ray EBF values were computed using Geometric Progression (G-P) method for photon energy 0.015 to 15 MeV up to penetration depths of 40 mfp (mean free path). The macroscopic effective removal cross-sections (Σ R ) for fast neutron (2 to 12 MeV) were calculated. At low- and high-energy region, the EBF values were found minimum whereas maximum in the intermediate-energy regions with a sharp peak below 100 keV for oxide containing glass samples. The investigation was carried out for potential applications of borate glasses for radiation shielding.

In the proposed work, an investigation on hazard assessment by lead element and natural radioactivity in cosmetic samples collected from various countries is presented. These samples were face powder, eyebrow paint and henna. The lead element in cosmetic samples was determined using particle-induced X-ray emission. Maximum natural radioactivity concentrations of 226Ra and 40K were found in khol and make-up cosmetic samples, respectively. The qualitative analysis of cosmetic samples showed that lead is the most toxic element found in eyebrow paint samples.

Monte Carlo N-particle (MCNP) code has been used to simulate the transport of gamma photon rays of different energies (22, 31, 59.5 and 81 keV) to estimate the iron content in solutions. In this study, MCNP simulation results are compared with experiment and XCOM theoretical data. The simulation shows that the obtained results are in good agreement with experimental data, and better than the theoretical XCOM values. The study indicates that MCNP simulation is an excellent tool to estimate the iron concentration in the blood samples. The MCNP code can also be utilized to estimate other trace elements in the blood samples.

In the present work, different methods were used to determine the effective atomic numbers of some low-Z materials, namely, polyethylene (PE), polystyrene (PS), polypropylene (PP), Perspex (PX), polycarbonate (PC), nylon 6-6 (PA-6), plaster of Paris (POP), and TH/L2. These methods are the direct method, the interpolation method, Auto-Zeff software, and single value XMuDat computer program. Some of the results obtained were compared with experimental data wherever possible. It can be concluded from this work that the effective atomic numbers calculated with the direct, the interpolation and Auto-Zeff methods demonstrate a good agreement in Compton scattering and pair production energy regions. A large difference in the effective atomic numbers calculated by the direct and the interpolation methods of low-Z materials was also observed in photoelectric and pair production regions. It was determined that PE, PS, PX, and PA-6 were equivalent to adipose and muscle; POP was equivalent to cortical bone; TH/L2 was equivalent to thyroid tissue; PP was equivalent to yellow bone marrow and adipose tissues; PC was equivalent to spongiosa.

Shielding of a reactor is required for protection of people and environment during normal operation and accidental situations. In the present paper we investigated the shielding parameters viz. mass attenuation coefficients, linear attenuation coefficients, tenth-value layer, effective atomic numbers, kerma relative to air and exposure buildup factors for gamma-ray for ordinary, heavy, and super heavy concretes. Macroscopic effective removal cross-sections for fast neutron had also been calculated. Ordinary concrete is economically suitable for mixture high energy gamma-ray and neutron as it has large weight fraction of low-Z as compared with super heavy concretes to slow down the neutron. Super heavy concretes are superior shielding for both reactor operation and accident situations. The study is useful for optimizing for shielding design and radiation protection in the reactors.

The gamma-ray exposure build-up factors of raw materials of bricks (soils and fly-ashes) in the state of Punjab were investigated for the photon energy range 0.015 to 15 MeV up to 40 mfp penetration depth by the geometrical progression (GP) method. Appreciable variations in the exposure build-up factor (EBF) are noted for the raw materials. The EBFs of the raw materials of bricks change depending on the photon energy, penetration depth and chemical composition. The build-up factors are low at low and high photon energies, whereas they are very high in the medium-energy region. The peak energy of the EBF for soils is 0.3 MeV and 0.2 MeV for fly ashes. The EBFs of the raw materials of bricks are also compared with those of bricks of red mud and common brick materials. Common bricks were found to have the lowest gamma-ray EBF. This study should be useful for emergency preparedness planning and emergency dose estimation for future planned nuclear power plants in the state of Punjab.

The mass attenuation coefficient (µ/ρ), effective atomic number (ZPleff ) and effective electron density (Neff ) of carbon steel and stainless steels were computed by using the WinXcom program. The µ/ρ values are higher in the photo-electric absorption and pair production region and approximately constant in the Compton scattering region. The variation in µ/ρ values is explained by partial interaction processes. The effective atomic numbers of the steels were also calculated by the Auto-Zeff program. The ZPleff values of the steels were compared with experimental results for available energies and were found to be in good agreement. SS304L shows equal values of effective atomic number by both the methods in the region of interest. The electron densities of the selected steels are observed to be equal and approximately constant in the Compton scattering region.

Effective atomic numbers (ZPIeff) and electron densities of eighteen alcohols such as wood alcohol, CH3OH; grain alcohol, C2H5OH; rubbing alcohol, C3H7OH; butanol, C4H9OH; amyl alcohol, C5H11OH; cetyl alcohol, C16H33OH; ethylene glycol, C2H4(OH)2; glycerin, C3H5(OH)3; PVA, C2H4O; erythritol, C4H6(OH)4; xylitol, C5H7(OH)5; sorbitol, C6H8(OH)6; volemitol, C7H9(OH)7; allyl alcohol, C3H5OH; geraniol, C10H17OH; propargyl alcohol, C3H3OH; inositol, C6H6(OH)6, and menthol, C10H19OH have been calculated in the photon energy region of 1 keV-100 GeV. The estimated values have been compared with experimental values wherever possible. The comparison of ZPIeff of the alcohols with water phantom and PMMA phantom indicate that the ethylene glycol, glycerin, and PVA are substitute for PMMA phantom and PVA is substitute of water phantom. ZPIeff of alcohols have also been compared with human organs and tissues. Ethylene glycol, glycerin and PVA, allyl alcohol, and wood alcohols are found tissue substitutes for most of human organs. Kerma which is the product of the energy fluence and mass energy-absorption coefficient, have been calculated in the energy region from 1 keV to 20 MeV for the alcohols. The results show the kerma is more or less independent of energy above 100 keV.

Gamma-ray energy absorption buildup factors of gaseous mixtures; neon (95%) + argon (5%), argon (95%) + acetylene (5%), argon (95%) + methane (5%), argon (95%) + carbon dioxide (5%), methane (70%) + pentane (30%) and argon (90%) + methane (10%) were studied by Geometrical Progression (G-P) fitting for the photon energy range 0.015-15 MeV. It was found that the equivalent atomic number, Z eq of the gaseous mixtures sharply reduces after 1 MeV photon energy. The Z eq for the mixture of methane (70%) + pentane (30%) is the minimum, whereas the maximum is for argon (95%) + carbon dioxide (5%) for the photon energies under investigation. The Energy Absorption Buildup Factor (EABF) for methane (70%) + pentane (30%) was found to be the highest among all the selected gaseous mixtures. The chemical composition of the gaseous mixtures has an impact on the EABF values for photon energy and penetration depth. The investigation of the EABF is useful for selection of gaseous mixtures in design consideration of gaseous radiation detectors for gamma radiation.

Investigation of Nanoparticle Effect on Radiation Shielding Property Using Monte Carlo Method Radiation protection and choice of appropriate materials in the areas of medical and industrial applications has become one of the major research topics. In this study, the increment in mass attenuation coefficients by doping of nano-sized barite (BaSO4) into the lead (Pb) have been investigated. The validation of generated MCNPX simulation geometry is provided by comparison with the previous experimental and theoretical studies. This generated geometry was used for the definition of nano-BaSO 4 into lead material and calculations. It was found that nano-BaSO 4 doped lead increased the amount of radiation absorbed in the material inside and as a result of which affected the radiation attenuation properties of material. This study also showed that MCNPX is an effective code on nano size studies and standarised geometry can be useful for further investigations. Radyasyon Zirhlama Ozelliginde Nanoparcacik Etkisinin Monte Carlo Metodu Kullanarak Incelenmesi Radyasyondan korunma ve uygun malzeme secimi medikal ve endustriyel radyasyonun kullanildigi alanlarda baslica arastirma konularindan bir tanesi haline gelmistir. Bu calismada, kursun (Pb) icerisine nano boyutlarda barit (BaSO 4 ) katkisi yapilarak kutle zayiflatma katsayisinda meydana getirdigi artis incelenmistir. Olusturulan MCNPX simulasyon geometrisinin validasyonu onceki deneysel ve teorik olcumler ile saglanmistir. Olusturulan bu geometri nano BaSO 4 parcaciklarinin kursun malzeme icerisine tanimlanmasinda ve hesaplamalarda kullanilmistir. Sonuc olarak nano boyutlarda kursun icerisine katkilanan BaSO 4 nanoparcaciklarikursunun kutle zayiflatma katsayisinda bir artisa sebep olmus, malzeme icerinde sogurulan radyasyon miktari artmis ve malzemenin radyasyonun zayiflatma ozelliklerini etkilemistir. Bu calisma ayrica MCNPX kodunun nano boyutlardaki calismalarda etkili bir program oldugunu ve standartize edilen bu geometrinin gelecek calismalar icin kullanilabilirligini gostermistir.

Total mass attenuation coefficients, ?m, effective atomic number, Zeff, and effective electron density, Neff, of different gases - carbon dioxide, methane, acetylene, propane, butane, and pentane used in radiation detectors, have been calculated for the photon energy of 1 keV to 100 GeV. Each gas has constant Zeff values between 0.10 to 10 MeV photon energies; however, these values are way far away from ICRU tissue. Carbon dioxide gas shows the closest tissue equivalence in the entire photon energy spectrum. Relative tissue equivalences of the mixtures of gases with respect to ICRU tissue are in the range of 0.998-1.041 for air, argon (4.5%) + methane (95.5%), argon (0.5%) + carbon dioxide (99.5%), and nitrogen (5%) + methane (7%) + carbon dioxide (88%). The gas composition of xenon (0.5%) + carbon dioxide (99.5%) shows 1.605 times higher tissue equivalence compared to the ICRU tissue. The investigated photon interaction parameters are useful for exposure and energy absorption buildup factors calculation and design, and fabrication of gaseous detectors for ambient radiation measurement by the Geiger-Muller detector, ionization chambers and proportional counters.

We calculated mass attenuation coefficients, effective atomic numbers and Kerma relative to air for human organ and tissue substitutes (i.e. wax, plastic and polymer materials). The effective atomic numbers of the tissue substi- tutes were calculated by the direct method, interpolation method, Auto-Zeff software and single value XMuDat program and then compared. The calculated effective atomic numbers were also compared with available experimental data and a good agreement was observed. A large difference in effective atomic numbers calculated by the direct and interpola- tion methods was observed in photoelectric and pair-production regions. The direct method was found to be appropriate for effective atomic number computation in low-(>10 keV) and medium-(0.1 ≤ E ≤ 10 MeV) photon energy regions. Kerma relative to air of the selected tissue substitutes was found to be dependent upon the atomic number and element compositions, which show a sharp peak due to K-edge absorption.

The mass attenuation coefficients, μ/ρ, half-value layer, HVL, tenth-value layer, TVL, effective atomic numbers, ZPIeff, and effective electron densities, Ne,eff, of borate glass sample systems of (100-x-y) Na2B4O7 : xPbO : yNiO (where x and y=0, 2, 4, 6, 8, and 10 weight percentage) containing PbO and NiO, with potential gamma ray and neutron shielding applications, have been investigated. The gamma ray interaction parameters, μ/ρ, HVL, TVL, ZPIeff, and Ne,eff, were computed for photon energy range 1 keV–100 GeV. The macroscopic fast neutron removal cross-sections (ΣR) have also been calculated. Appreciable variations were noted for all the interaction parameters by varying the photon energy and the chemical composition of the glass samples. The better shielding properties of borate glass samples containing PbO were found. These results indicated that borate glass samples are a good radiation shielding material.