基于瞬发γ中子活化分析技术的日遗化武鉴别方法研究  

Study on Identification of Chemical Warfare Agents Abandoned by Japanese Army in China Based on PGNAA

作　　者：肖雄 艾宪芸 张济鹏 肖无云 赵冬[2] 张斌 李京伦 XIAO Xiong;AI Xianyun;ZHANG Jipeng;XIAO Wuyun;ZHAO Dong;ZHANG Bin;LI Jinglun(State Key Laboratory of NBC Projection for Civilian,Beijing 102205,China;Institute of Nuclear Analytical Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]国民核生化灾害防护国家重点实验室,北京102205 [2]南京航空航天大学核分析技术研究所,江苏南京211106

出　　处：《原子能科学技术》2023年第10期1989-1999,共11页Atomic Energy Science and Technology

基　　金：国家自然科学基金(12075318)。

摘　　要：日本战败后遗弃在我国境内的数百万枚化学弹亟待销毁处理,而对弹型的准确鉴别是处置和销毁的前提。基于瞬发γ射线中子活化分析(PGNAA)技术,对现有手段难以区分的黄弹、青白弹以及燃烧弹开展鉴别研究,利用Geant4软件分别计算了采用^(252)Cf源、D-D和D-T中子发生器作中子源,聚乙烯或铅材质作反射体的情况下,上述3种弹型的中子诱发特征γ谱,并进行了实验验证。谱分析结果表明,对于燃烧弹中的特征元素P和S,主要检测特征γ射线能量分别为1266 keV和2230 keV,Cl元素的882/1763 keV特征峰与1951/1959 keV特征峰的计数之比可作为鉴别黄弹和青白弹的重要依据。从中子源的选型、反射体的选择、特征元素库的建立以及判别方法等方面,为基于PGNAA技术鉴别日遗化武提供了重要的参考依据。Tens of thousands of chemical warfare agents were abandoned in China by the Japanese army after their defeat of invasion of China.Most of the chemical warfare agents have been buried in the soil for more than half a century and the risk of chemical toxicants leakage has increased sharply due to corrosion,so the disposal of these weapons is urgent.The effective disposal and destruction of chemical warfare agents are based on the accurate identification.Prompt gamma neutron activation analysis(PGNAA)is a multi-element analysis technology with low invasion,good safety and high accuracy.In this paper,to study the discrimination potentiality of PGNAA technology on the Japanese chemical projectiles abandoned in China,which can’t be identified by the visual inspection and X-ray imaging technology,the discriminant logic tree of the projectiles was established by investigating and analyzing the data of these abandoned chemical warfare agents,and the simulation model of neutron activation analysis of these projectiles was established by the use of Geant4 toolkit.The prompt gamma spectra of incendiary,yellow projectile and blue projectile excited by ^(252)Cf source,D-D neutron generator and D-T neutron generator with neutron yield of 1×10^(7) s-1 were calculated respectively.For the generation of neutrons from ^(252)Cf source,the Watt fission spectrum was used in our simulations.Monoenergetic 2.5 MeV neutrons and 14.1 MeV neutrons were set as D-D neutron generator and D-T neutron generator respectively in our simulations.The reflection effect of neutron reflectors made of lead or polyethylene on neutrons has also been studied in the simulation.To verify the simulation results,an experimental platform was set up with a D-T neutron generator and a N-type HPGe detector with relative efficiency of 55%.The samples under test were made up of non-toxic and harmless chemical agent,the elements composition and mass fraction were closed to the real chemical warfare agents.The results show that for characteristic elements P and S,t

关 键 词：化学武器 PGNAA GEANT4 中子发生器 ^(252)Cf 

分 类 号：TL816.5[核科学技术—核技术及应用]