최근 납의 대체물질로서 연구되고 있는 바륨(Ba)과 요오도(I) 등은 차폐능은 우수하지만, 30 keV 근처의 에너지 영역에서 특성 X선이 방출되는 문제점이 있다. 본 연구에서는 황산바륨(BaSO4)과 산화비스무스(BiO)로 구성된 친환경 이중차폐체의 적용가능성을 검증하기 위한 선행연구로 몬테카를로 시뮬레이션을 통해 투과스펙트럼, 차폐율 등을 평가하였다. 평가결과, 0.6mm 두께의 Pb 단일층과 비교하여 0.1 mm 두께의 BaSO4 하부층에 BiO 층의 두께가 0.4 mm 와 0.5 mm에서는 각각 차폐율이 1.9 %, 3.9 % 높은 성능을 보였다. 뿐만 아니라, 상대적인 중량 또한 각각 34.5 %, 28 % 경량화가 가능하다는 것을 알 수 있었다.

Recently, a barium(Ba) and an iodine(I) being studied as a conventional lead(Pb) alternatives of shielding material has excellent shieding rate, but the characteristic x-ray photons in the energy range near 30 keV line is released. In this study, with bismuth oxide(BiO) coupled barium sulfate(BaSO4) double layer, transmitted spectra, shieding rates and relative weighting rates were evaluated to validate the applicability of eco-friendly double layer shieding structure using monte carlo simulations as a prior study. From the evaluation results, in 0.4mm and 0.5mm thickness of BiO layers coupled with top 0.1mm-BaSO4 layer, the shieding rate showed 1.9% and 3.9% higher than 0.6mm thickness of Pb single layer, respectively. In addition, the relative weight also 28% and 34.5% lower than 0.6mm-Pb in 0.4mm and 0.5mm thickness of BiO layers coupled with top 0.1mm-BaSO4 layer.

ABSTRACT
 Ⅰ. INTRODUCTION
 Ⅱ. MATERIAL AND METHODS
 Ⅲ. RESULT AND DISCUSSION
  1. 이중구조 차폐체의 투과 스펙트럼
  2. 이중구조 차폐체의 차폐능
 Ⅳ. CONCLUSION
 Reference
 요 약

• Ji Koon Park(Department of Radiological Science, International University of Korea) | 박지군
• Il Hong Choi(Department of Radiological Science, International University of Korea) | 최일홍
• Hyung Hoo Park(Department of Radiological Science, International University of Korea) | 박형후
• Sung Woo Yang(Department of Radiological Science, International University of Korea) | 양승우
• Sang Sik Kang(Department of Radiological Science, International University of Korea) | 강상식 Corresponding Author
• Kyo Tae Kim(Department of Biomedical Engineering, Inje University) | 김교태