### ESR and XPS analysis of schima superba powder after γ-rays irradiation

ZHANG Wenhui1   CHEN Qiong2

1. 1(College of Mechanical and Electrical Engineering, Fujian Agricultural and Forestry University, Fuzhou 350002, China)
2(College of Computer and Information Science, Fujian Agricultural and Forestry University, Fuzhou 350002, China )
• Received:2012-01-16 Revised:2012-04-28 Online:2012-10-20 Published:2014-09-11

Abstract:

Electron spin resonance (ESR) and X-rays photoelectron spectroscopy (XPS) techniques were used to study the variation of the free radical, the chemical structure and components of the schima superba powder irradiated by 60Co γ-rays. The results show that the intensity of free radicals increases with the absorbed doses according to the exponential law of when the spectral splitting factor of the free radicals (g) is 2.0033. The O/C atomic ratio in the schima superba powder surface increases slightly after 200 kGy dose irradiation. At the same time, the contents of the C–C, C–H and C–O increase, and the C=O content decreases. The content of the –O–C=O increases to 2.5 times of the original. These phenomena may indicate that some oxygen-containing functional groups occurred on the schima superba surface and the structure of organic carbon has been changed.

Key words: Schima superba, γ-rays, ESR, XPS

CLC Number:

• S781.4