伽马射线对沙林模拟物O,O’-二甲基甲基膦酸酯的辐射降解作用  

Gamma Radiolysis of Dimethyl Methyl Phosphonate as a Stimulant for Sarin

作　　者：郁卫飞[1] 张勇[1] 胡思得[2] 孙颖[2] 李海波[1] 李晓燕[3] 

机构地区：[1]中国工程物理研究院化工材料研究所,四川绵阳621900 [2]中国工程物理研究院,四川绵阳621900 [3]中国工程物理研究院核物理与化学研究所,四川绵阳621900

出　　处：《核化学与放射化学》2010年第1期52-56,共5页Journal of Nuclear and Radiochemistry

基　　金：中国工程物理研究院专项基金(62601080313)

摘　　要：研究了伽马射线对沙林模拟物O,O’-二甲基甲基膦酸酯(DMMP)的辐射降解作用。以Co-60源为射线源,选取剂量率分别为40、60、77、98、115 Gy/min,用气相色谱法测试辐射样品中残余DMMP的质量分数(w(DMMP)),对实验测试误差及其影响因素进行了控制和改进。结果表明,封装和取样过程存在0.33%~0.52%的损失;辐射平行样的测试值之间相差0.08%~0.71%;各个辐射样测试值的标准偏差在0.01%~0.40%之间;辐射样存放时间对样品的影响较大,不同存放时间导致样品中w(DMMP)测试值相差-1.8%^+2.9%;辐射样中w(DMMP)随剂量的增加而明显降低,而随辐射剂量率的增加变化趋势不明显,剂量是DMMP辐射降解作用中的主要影响因素。GC-MS测得了辐射样中的气态小分子产物和有机磷大分子产物,表明辐射过程符合自由基反应历程;得到辐射化学产额G值在0.75~1.0μmol/J,随剂量增加而有所降低;在剂量2 000 kGy条件下,DMMP分解率为16.24%,这显示单一的物理或化学作用方式难以充分地降解DMMP,也显示出多效应综合作用的必要性。Gamma-radiation decomposition effects were researched on O, O’-dimethyl methyl phosphonate （DMMP） as a stimulant for sarin. Gamma ray dose rate 40, 60, 77, 98, 115 Gy/min and dosage 100, 200, 500, 1 000, 2 000 kGy from a cobalt 60 gamma resource were used in this study. Irradiated samples were analyzed with gas chromatography and measurement errors of remaining DMMP were detailed with its influencing factors. They were shown that process of sealing and sampling led to DMMP loss about 0.33%-0.52%, DMMP contents of parallel samples differed by 0.08%-0.71%, standard deviation of contents value was about 0. 01%-0. 40 % , and storage period also led to remarkable variance of DMMP content in irradiated samples which ranged from -1.8% to ＋2.9%. DMMP residue content inside samples were determined to decrease evidently with increase of dosage while indistinctively with increase of dose rate, which meant that the dosage should be a dominant factor. GC-MS analysis showed a number of decomposition products including gaseous small molecules and organic phosphorus molecules, which was in accord with free radical reaction mechanism. Radiation chemistry yields G were calculated within 0.75- 1.0 μmol/J, which decreased with increase of dosage. With most intensive gamma ray parameters including dosage 2 000 kGy and dose rate 114.92 Gy/min, as much as 83.7% of DMMP was found undecomposed. Decomposition rate should be 16.24%, indicating a single mode of physical or chemical action unable to fully decompose DMMP, and also showing the need for combination of multiple means of degradation.

关 键 词：沙林 O O’-二甲基甲基膦酸酯 辐射降解 伽马射线 

分 类 号：Q615.11[生物学—生物物理学]