中文摘要：

低能离子注入引起生物体诱变效应的机理一直是人们关注的问题。DNA是辐射作用的靶，文章对低能氮离子注入胸腺嘧啶后的样品进行了XPS研究，发现注入后C，N，O三元素的质量百分比的相对值发生了变化，N，O含量下降，C含量明显增加。精细结构分析发现，O（1s）峰的峰位发生偏移，N（1s）峰由注入前的单峰变为3个峰，C（1s）峰由注入前的2个峰变为注入后的单峰，说明注入后各元素所处的化学环境和物理结构都发生了较大改变，N^＋注入能导致胸腺嘧啶分子结构的破坏，改变原结构状态。

英文摘要：

The induced variation mechanism of low energy ion beam implantation into a creature has attracted a great attention. DNA was the target of radiation. XPS analysis of thymine sample implanted by low energy N^＋ was studied. It was found that the relative content of C, N and O changed in the implanted samples. The content of N and O decreased, while that of C increased. Subtle structure of C, N and O was studied. It was found that the peak location of O（1s） shifted. The peak number of N（ls） changed from one to three, while that of C（1s） changed from two to one. The results indicated that the chemical environment and physical structure changed greatly by implantation. N^＋ implantation could lead to destruction and change of thymine molecular structure.