Search for Tissue Equivalent Materials Based on Exposure and Energy Absorption Buildup Factor Computations

Tissue equivalent materials (TEM) are frequently used in research as a means to determine the delivered dose to patients undergoing various therapeutic procedures. They are used in routine quality assurance and quality control procedures in diagnostic and therapeutic physics. However, very few materials that are tissue equivalent have been developed for use in research at the low photon energies involved in diagnosis radiology. The objective of this study is to describe a series of TEMs designed to radiographically imitate human tissue at diagnostic photon energies. TEMs for adipose, cortical bone, fat, lung, and muscle tissues were investigated in terms of energy absorption and exposure buildup factors for photon energy range 15–150 keV and for penetration depths up to 40 mean free path. BUF was computed based on GP-fitting method. Moreover, we also compared some radiological properties, including the total attenuation and the energy-absorption attenuation, the effective atomic number, and the CT number at 30, 100, and 120 kVp. We found that SB3, Glycerol trioleate, and MS15 perfectly mimic cortical bone, fat, and muscle tissues, respectively. Additionally, AP6 and Stracey latex are good TEM for adipose and lung tissues, respectively. The results of this work should be useful in radiation diagnosis and dosimetry applications for the large physician researcher community.

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In Silicon Monte Carlo Simulation Trials for Investigation of V2O5 Reinforcement Effect on Ternary Zinc Borate Glasses: Nuclear Radiation Shielding Dynamics

Materials ◽

10.3390/ma14051158 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1158

Author(s):

Huseyin O. Tekin ◽

Shams A. M. Issa ◽

Gokhan Kilic ◽

Hesham M. H. Zakaly ◽

Mohamed M. Abuzaid ◽

...

Keyword(s):

Effective Atomic Number ◽

Mean Free Path ◽

Radiation Shielding ◽

Nuclear Radiation ◽

Zinc Borate ◽

Linear Attenuation Coefficient ◽

Buildup Factor ◽

Glass Composites ◽

Mcnpx Code ◽

Negative Effect

In the current study, promising glass composites based on vanadium pentoxide (V2O5)-doped zinc borate (ZnB) were investigated in terms of their nuclear-radiation-shielding dynamics. The mass and linear attenuation coefficient, half-value layer, mean free path, tenth-value layer, effective atomic number, exposure-buildup factor, and energy-absorption-buildup factor were deeply simulated by using MCNPX code, Phy-X PSD code, and WinXcom to study the validation of ZBV1, ZBV2, ZBV3, and ZBV4 based on (100−x)(0.6ZnO-0.4B2O3)(x)(V2O5) (x = 1, 2, 3, 4 mol%) samples against ionizing radiation. The results showed that attenuation competencies of the studied glasses slightly changed while increasing the V2O5 content from 1 mol% to 4 mol%. The domination of ZnO concentration in the composition compared to B2O3 makes ZnO substitution with V2O5 more dominant, leading to a decrease in density. Since density has a significant role in the attenuation of gamma rays, a negative effect was observed. It can be concluded that the aforementioned substitution can negatively affect the shielding competencies of studied glasses.

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A Monte Carlo investigation of some important radiation parameters and tissue equivalency for photons below 1 keV in human tissues

Biomedical Physics & Engineering Express ◽

10.1088/2057-1976/ac428f ◽

2021 ◽

Author(s):

Mustafa Mohammad Rafiei ◽

Sara Parsaei ◽

Parminder Kaur ◽

Kanwar J Singh ◽

Mehmet Büyükyıldız ◽

...

Keyword(s):

Atomic Number ◽

Gamma Ray ◽

Effective Atomic Number ◽

Mean Free Path ◽

Relative Difference ◽

Eye Lens ◽

Equivalent Material ◽

Human Tissues ◽

Attenuation Coefficients ◽

Tissue Equivalent

Abstract The attenuation coefficients are important input values in estimating not only the dose and exposure in radiotherapy and medical imaging, but also in the proper design of photon shields. While studies are widely available above 1 keV, the attenuation coefficients of human tissues for photon energies less than 1 keV have not been studied yet. In this study, the attenuation coefficients of water and some human tissues were estimated for low energy photons using the MCNP6.1 code in the energy region 0.1 keV-1 keV. Mass attenuation coefficients were estimated at photon energies of 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950 and 1000 eV for water and ten human tissues (Soft, Breast, Lung, Bone, Brain, Eye lens, Ovary, Skin, Thyroid and Prostate). Results were compared with those available in literature and a fairly good agreement has been obtained. These data were then used to calculate the mean free path, half value layer, tenth value layer, effective atomic number and specific gamma-ray constant (useful for calculation of dose rate) as well. Moreover, for comparison the effective atomic number of the water has been obtained using the results of this work and using the data available in NIST database from 0.1 to 1 keV. In addition, the human tissues were compared with some tissue equivalent materials in terms of effective atomic number and specific gamma-ray constant to study the tissue equivalency from the results, the muscle-equivalent liquid with sucrose has been found to be the best tissue equivalent material for soft tissue, eye lens and brain with relative difference below 4.1%.

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A Systematical Characterization of TeO2–V2O5 Glass System Using Boron (III) Oxide and Neodymium (III) Oxide Substitution: Resistance Behaviors against Ionizing Radiation

Applied Sciences ◽

10.3390/app11073035 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3035

Author(s):

H. O. Tekin ◽

Shams A. M. Issa ◽

G. Kilic ◽

Hesham M. H. Zakaly ◽

N. Tarhan ◽

...

Keyword(s):

Gamma Ray ◽

Effective Atomic Number ◽

Mean Free Path ◽

Radiation Shielding ◽

Glass System ◽

Buildup Factor ◽

Attenuation Coefficients ◽

Gamma Ray Attenuation ◽

Buildup Factors

This study aimed to perform an extensive characterization of a 74.75TeO2–0.25V2O5–(25 − x)B2O3-xNd2O3 glass system with (x = 0, 0.5, 1.0, and 1.5 mol%) for radiation shielding properties. Linear and mass attenuation coefficients were determined using Phy-X PSD software and compared with the simulation using Monte Carlo software MCNPX (version 2.7.0). Half value layer, mean free path, tenth value layer, effective atomic number, exposure buildup factor, and energy absorption buildup factors of VTBNd0.0, VTBNd0.5, VTBNd1.0, and VTBNd1.5 glasses were determined, respectively. The results showed that boron (III) oxide and neodymium (III) oxide substitution has an obvious impact on the gamma ray attenuation properties of the studied glasses. It can be concluded that the VTBNd1.5 sample with the highest content of neodymium (III) oxide (1.5 mol%) is the superior sample for shielding of gamma radiation in the investigated energy range.

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Gamma-ray shielding parameters of Li2B4O7 glasses: undoped and doped with magnetite, siderite and Zinc-Borate minerals cases

Radiochimica Acta ◽

10.1515/ract-2019-0014 ◽

2019 ◽

Vol 107 (8) ◽

pp. 755-765 ◽

Cited By ~ 5

Author(s):

Nergiz Yıldız Yorgun

Keyword(s):

Photon Energy ◽

Atomic Number ◽

Effective Atomic Number ◽

Diffraction Method ◽

Mean Free Path ◽

Zinc Borate ◽

Buildup Factor ◽

Transmission Method ◽

Incident Photon ◽

Mass Attenuation

Abstract Designing new shielding materials and calculating their shielding parameters are important task to keep living in safe from hazardous effects of radiation. In this study, the lithium borate glasses with chemical formula (Li2B4O7)(100−x)Yx (x = 0, 10, 20, 30 and 40 wt % and Y = magnetite, siderite and zinc-borate) were fabricated via melt quenching technique. X-ray diffraction method was employed to confirm amorphous structure of fabricated glass samples. The glass sample’s shielding parameters such as mass attenuation coefficient, effective atomic number, and half value layer were measured experimentally by the narrow beam transmission method for 81, 276, 302, 356, and 383 keV of incident photon energies. Also, WinXCom software was used to calculate theoretical shielding parameters from 1 keV to 105 MeV photon energy. Moreover, Geometric Progression (G–P) method was used to calculate exposure buildup factor (EBF) values for incident photon energy 0.015 MeV–15 MeV up to penetration depths of 40 mfp (mean free path). Among the obtained results, while Li2B4O7 glass with magnetite 40 % has the highest mass attenuation and effective atomic number, it has the lowest half value layer and exposure buildup factor. The results show that the fabricated glass systems could be considered as a good candidate for radiation safety.

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Newly Developed Vanadium-Based Glasses and Their Potential for Nuclear Radiation Shielding Aims: A Monte Carlo Study on Gamma Ray Attenuation Parameters

Materials ◽

10.3390/ma14143897 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3897

Author(s):

Huseyin Ozan Tekin ◽

Ghaida Bilal ◽

Hesham M. H. Zakaly ◽

Gokhan Kilic ◽

Shams A. M. Issa ◽

...

Keyword(s):

Glass Sample ◽

Gamma Ray ◽

Effective Conductivity ◽

Effective Atomic Number ◽

Mean Free Path ◽

Radiation Shielding ◽

Nuclear Radiation ◽

Buildup Factor ◽

Doped Glass

This study aimed to investigate different types of glasses based on the 46V2O5-46P2O5-(8-x) B2O3-xCuO system in terms of their nuclear radiation shielding properties. Accordingly, five different CuO-doped vanadate glasses were investigated extensively to determine the necessary gamma shielding parameters along with effective conductivity at 300,000 and buildup factors. Phy-x PSD software was used for determination of these vital parameters. Furthermore, these parameters, such as half value layer, tenth value layer, and mean free path were investigated in a broad energy range between 0.015 and 15 MeV. The results revealed that the amount of CuO reinforced in each sample plays an essential role in determination of the shielding abilities of the samples. The sample with the highest CuO content had the highest linear attenuation coefficient and mass attenuation coefficient values. Additionally, the lowest mean free path, half value layer, and tenth value layer values were recorded for glass sample VPCu8. There was an inverse relation between the effective conductivity and effective atomic number and photon energy; that is, as energy increases, the effective conductivity and effective atomic number decreased rapidly, especially in the regions of low energy. Glass sample VPCu8 reported the highest values for both parameters. Moreover, glass sample VPCu8 had the lowest exposure buildup factor and energy absorption buildup factor values. Our findings showed that CuO-reinforced vanadate glass composition, namely 46V2O5-46P2O5-8CuO, with a glass density of 2.9235 g/cm3, was reported to have superior gamma ray attenuation properties. These results would be helpful for scientists in determining the most appropriate additive rare earth type, as well as the most appropriate glass composition, to offer shielding characteristics similar to those described above, taking into consideration the criteria for usage and the needs of the community. The results of this research will be useful to the scientific community in evaluating the prospective characteristics of CuO-doped glass systems and related glass compositions. CuO-doped glass systems and associated glass compositions have a wide range of properties.

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The Potentials of Egyptian and Indian Granites for Protection of Ionizing Radiation

Materials ◽

10.3390/ma14143928 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3928

Author(s):

Mohamed Elsafi ◽

M. F. Alrashedi ◽

M. I. Sayyed ◽

Ibrahim F. Al-Hamarneh ◽

M. A. El-Nahal ◽

...

Keyword(s):

Attenuation Coefficient ◽

Atomic Number ◽

Effective Atomic Number ◽

Mean Free Path ◽

High Energy ◽

Radiation Shielding ◽

Linear Attenuation Coefficient ◽

Buildup Factor ◽

Practical Applications ◽

Wide Range

This paper aims to study the radiation shielding characteristics and buildup factor of some types of granite in Egypt. The mass attenuation coefficient (MAC) for three types of granite (gandola, white halayeb, and red aswani) was experimentally determined, and the experimental results were validated by XCOM software. The relative deviation between the two methods does not exceed 3% in all discussed granite samples, which means that MAC calculated through the experimental and XCOM are in suitable agreement. The effective atomic number (Zeff) varies from 13.64 to 10.69, 13.68 to 10.59, and 13.45 and 10.66 for gandola, white halayeb, and red aswani, respectively. As well as the equivalent atomic number (Zeq) was calculated in a wide range of energy to deduce the exposure (EBF) and energy absorption (EABF) buildup factors for the studied granite materials. The linear attenuation coefficient (LAC), half-value layer (HVL), mean free path (MFP) were calculated at each investigated energy and showed that the most effective shielding ability at high energy was red aswani, while at low energy, the shielding ability was nearly constant for studied granites. The present study forms the first endeavor to obtain the radiation shielding properties of the studied materials to be used in practical applications.

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Gamma, Fast Neutron, Proton, and Alpha Shielding Properties of Borate Glasses: A Closer Look on Lead (II) Oxide and Bismuth (III) Oxide Reinforcement

Applied Sciences ◽

10.3390/app11156837 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6837

Author(s):

Ghada ALMisned ◽

Huseyin O. Tekin ◽

Esra Kavaz ◽

Ghaida Bilal ◽

Shams A.M. Issa ◽

...

Keyword(s):

Heavy Metal ◽

Metal Oxide ◽

Gamma Radiation ◽

Fast Neutron ◽

Effective Atomic Number ◽

Mean Free Path ◽

Oxide Glass ◽

Borate Glasses ◽

Radiation Attenuation ◽

Shielding Properties

The purpose of this research was to investigate the shielding characteristics of high-amount heavy metal oxide and Eu3+-activated borate glasses based on 10La2O3–50HMO–(40–x) B2O3–xEu2O3 (x = 0, 0.5, 1, 2, and HMO = PbO, Bi2O3). Critical gamma radiation attenuation characteristics, particularly mass attenuation coefficients of investigated heavy metal oxide glass samples, were determined using Monte Carlo simulations and the Phy-x/PSD software. Following that, we looked at the half-value layer, mean free path, effective atomic number, and build-up factors across a broad energy range (0.015–15 MeV). According to the study’s results, the addition of Eu2O3 enhanced the mass attenuation coefficient and effective atomic number, while reducing the half-value layer, mean free path, and accumulation factors. In terms of gamma radiation attenuation, the LBi50BEu glass system surpassed the LPb50BEu glass system in terms of overall shielding properties against nuclear radiation. Additionally, the heavy metal oxide glass’ efficacy as a neutron shield was determined using fast neutron removal cross-sections (ΣR). LBi50BEu2 glass was shown to be more effective in preventing the penetration of charged particle radiation.

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