Development of New Radiation Shielding Materials: The Role of Rare Earth Elements

Abstract

Bismuth and Lead are commonly used for radiation shielding to mitigate risks such as radiation damage and cancer. However, these materials are costly and impractical for certain applications. This study aims to explore the attenuation properties of various elements and composites using Monte Carlo simulations to develop improved radiation shielding materials. GAMOS software was employed to simulate materials with thicknesses ranging from 0.1 to 2.0 mm and x-ray energies between 10 and 150 keV. Initial simulations focused on validating bismuth and lead by calculating their mass attenuation coefficients, which matched NIST (National Institute of Standards and Technology) values within a 2% margin of difference. After verification, the study simulated various shielding materials incorporating metals and rare earth elements. Among these, four composites with rare earth elements demonstrating the highest mass attenuation coefficients were selected. These composites exhibited superior absorption in the 50–80 keV energy range compared to bismuth and lead.

Keywords

• Monte Carlo Method
• Rare Earth Elements
• Radiation Protection
• GAMOS

Yeni Radyasyon Zırh Malzemelerinin Geliştirilmesi: Nadir Toprak elementlerinin Rolü

Abstract

Bismut ve Kurşun, radyasyonun neden olduğu zarar ve kanser riskini azaltmak için yaygın olarak kullanılan koruma malzemeleridir. Ancak bu malzemeler, maliyetli ve bazı uygulamalar için pratik değildir. Bu çalışma, Monte Carlo simülasyonları kullanılarak çeşitli element ve bileşiklerin zayıflatma özelliklerini inceleyerek daha iyi radyasyon koruma malzemeleri geliştirmeyi amaçlamaktadır. GAMOS yazılımı, 0.1 ila 2.0 mm arasında değişen kalınlıklara sahip malzemeler ve 10 ila 150 keV enerji aralığındaki x-ışınları için simülasyonlar yapmak üzere kullanılmıştır. İlk simülasyonlar, bismut ve kurşunun kütle zayıflatma katsayılarını hesaplayarak bu malzemeleri doğrulamaya odaklanmış ve elde edilen değerler, NIST’in (Ulusal Standartlar ve Teknoloji Enstitüsü) verileriyle %2’lik bir fark içinde uyuşmuştur. Doğrulama sonrası, metaller ve nadir toprak elementleri içeren çeşitli koruyucu malzemeler simüle edilmiştir. Bunlar arasından, en yüksek kütle zayıflatma katsayısına sahip dört nadir toprak elementi katkılı bileşik seçilmiştir. Sonuç olarak, bu bileşiklerin 50–80 keV enerji aralığında bismut ve kurşuna kıyasla daha yüksek bir absorpsiyon sağladığı görülmüştür.

Keywords

• Monte Carlo Metot
• Nadir Toprak Elementleri
• Radyasyondan Korunma
• GAMOS

References

1. Chang, K.H., Lee, W., Choo, D.M., Lee, C.S., Kim, Y. 2010. Dose Reduction in CT Using Bismuth Shielding: Measurements and Monte Carlo Simulations, Radiation Protection Dosimetry, Vol. 138, no. 4, pp. 382-388, DOI: 10.1093/rpd/ncp278.
2. Raissaki, M., Perisinakis, K., Damilakis, J., Gourtsoyiannis, N. 2010. Eye-Lens Bismuth Shielding in Paediatric Head CT: Artefact Evaluation and Reduction, Pediatric Radiology, Vol. 40, no. 11, pp. 1748-1754, DOI: 10.1007/s00247-010-1715-6.
3. American Association of Physicists in Medicine (AAPM). 2012. AAPM Position Statement on the use of Bismuth Shielding for the Purpose of Dose Reduction in CT Scanning. PP 26-A.
4. National Measurement Office (NMRO). 2010. Rohs Guidance: Producer Support Booklet. 2-507-5089.
5. Çetin, H., Yurt, A., Yüksel, S.H. 2017. The Absorption Properties of Lead-Free Garments for use in Radiation Protection, Radiation Protection Dosimetry, Vol. 173, no. 4, pp. 345-350, DOI: 10.1093/rpd/ncw004.
6. Rogers, D. 2006. Fifty Years of Monte Carlo Simulations for Medical Physics, Physics in Medicine & Biology, Vol. 51, no. 13, pp. R287-R301, DOI: 10.1088/0031-9155/51/13/R17.
7. McCaffrey, J.P., Shen, H., Downton, B., et al. 2007. Radiation Attenuation by Lead and Nonlead Materials used in Radiation Shielding Garments, Medical Physics, Vol. 34, no. 2, pp. 530-537, DOI: 10.1118/1.2426404.
8. McCaffrey, J.P., Tessier, F., Shen, H. 2012. Radiation Shielding Materials and Radiation Scatter Effects for Interventional Radiology (IR) Physicians, Medical Physics, Vol. 39, no. 7, pp. 4537-4546, DOI: 10.1118/1.4730504.

9. Chakhmouradian, A., Wall, F. 2012. Rare Earth Elements: Minerals, Mines, Magnets (and more), Elements, Vol. 8, no. 5, pp. 333-340, DOI: 10.2113/gselements.8.5.333.
10. Hurst, C. 2010. China’s Rare Earth Elements Industry: What can the West Learn?. Institute for the Analysis of Global Security (IAGS), Washington, DC, USA.
11. McCollough, C.H., Primak, A.N., Braun, N., et al. 2009. Strategies for Reducing Radiation Dose in CT, Radiologic Clinics of North America, Vol. 47, no. 1, pp. 27-40, DOI: 10.1016/j.rcl.2008.10.006.
12. Zuguchi, M., Chida, K., Taura, M., et al. 2008. Usefulness of Non-Lead Aprons in Radiation Protection for Physicians Performing Interventional Procedures, Radiation Protection Dosimetry, Vol. 131, no. 4, pp. 531-534, DOI: 10.1093/rpd/ncn244.
13. Eder, H., Schlattl, H., Hoeschen, C. 2010. X-Ray Protective Clothing: Does DIN 6857-1 Allow an Objective Comparison Between Lead-Free and Lead-Composite Materials, Rofo, Vol. 182, no. 5, pp. 422-428, DOI: 10.1055/s-0028-1110000.
14. Arce, P., Lagares, J.I., Harkness, L., et al. 2011. Gamos: An easy and flexible way to use geant4, in: IEEE Nuclear Science Symposium Conference Record, pp. 2230-2237, DOI: 10.1109/nssmic.2011.6154455.
15. Medhat, M.E., Shirmardi, S.P., Singh, V.P. 2014. Comparison of GEANT4, MCNP Simulation Codes of Studying Attenuation of Gamma Rays Through Biological Materials with XCOM and Experimental Data, Journal of Applied & Computational Mathematics, Vol. 3, no. 5, p. 179, DOI: 10.4172/2168-9679.1000179.