A Study Of Physical Mechanisms For Implanted Heavy Ions With Low Energies In Colorful Cotton Seeds

In this dissertation, We study and measured the concentration-depth distribution of ion-implanted samples of the dry colorful cotton seeds and peanut seeds with four different energies and doses by scanning electron microscope and X-ray energy dispersion spectrometer. The experimental result of concentration-depth distribution for Ti+ Fe+ in peanut seeds is compared with the document's data, verified this experimental data is credibility. The concentration-depth distribution in colorful cotton seeds is emphases of discusses and analyze in this thesis. There are two kinds of entirely different point of views about the physical mechanism of mutagenic effect which DNA structure of cotyledon or embryonic cell of seeds was damaged caused by low energy heavy ion beam of implanting into the dry seed According to the point of statistics view, we analyzed the data of document and the curve of the concentration-depth distribution which implanted Ti~+ , Fe~+ into colorful cotton seeds in low energy heavy ions, and got some novel results that had been summarized in the following:1. The concentration-depth distribution of low heavy ion in plant's seed is a asymmetric Gaussian distribution with a long tail.2. It is called the possible depth that based on maximum concentrations about the curve of concentration-depth distribution of low energy heavy ion in plant's seed. The range of the possible depth is about to 5 ~ 40 um, which is less than ordinary testa thickness of plant's seed, thus result which DNA in embryonic cell is damaged is the Indirect Action of ion-implanted secondary effect.3. It is called the maximal penetration depth that based on the long tail about the curve. The difference value of the maximal penetration depth lies on measurement techniques and checkout sensitivity of surveying instrument. The measured value of the maximal penetration depth is about to 800 um by TPLSM, which is enough to...