低能N+注入植物种子射程分布的模拟计算

伴随着离子束生物技术的广泛应用, 国内许多单位开展了低能离子注入植物种子的实验研究. 其中关于低能离子注入植物种子诱变的物理机理, 集中在离子注入的深度-浓度分布上. 一些单位直接使用纵向非静态(LSS)理论和TRIM程序来计算低能离子注入植物种子的深度-浓度分布, 却发现计算结果与实验测量结果相差甚远. 所以在对植物种子靶材料进行处理和对LSS理论进行修正的基础上, 在二维近似情况下, 用蒙特卡罗方法分别模拟计算了200keV V⁺和20keV Ti⁺注入花生和棉花种子的射程分布, 得到了与实验结果较符合的曲线. 在此模型基础上, 计算了同样初始条件和理论计算模型下无法从实验上测量的N⁺注入植物种子的射程分布, 初步地为低能N⁺注入植物种子射程分布提供了一种理论计算方法.

Simulation of the Penetration Range Distribution for Nitrogen Ions Implanted into the Plant Seed at Low Energy

Following the widespread application of ion beam biological technology, more experimental researches on low energy ion impletation into plant seeds has been conducted. In the studies of the physical mechanism, the emphasis are put on the depth and concentration distribution of the ions implanted into the seeds at low energy. The calculations directly using the LSS theory and the TRIM program for the distribution of ions implanted into seeds at low energy are not in agreement with the experimental results. With considering targets and correctting LSS theory according to the distinguishing texture of plant seeds, we calculated the penetration range distribution for vanadium ions implanted into peanut seed at 200keV and for titanium ions energy implanted into the cotton seed at 20keV in two dimension approximation by using the Monte-Carlo method. The calculation results are in agreemante with experiments. After implated into the peanut seed or the cotton seed, the nitrogen ion range distribution, whith coold not be measured so far, was also calculated with the same initial condition and theory model. This could be a preliminary method for calculation of the range distribution of nitrogen implated into seeds at low energy.