Nuclear Techniques ›› 2018, Vol. 41 ›› Issue (1): 10202-010202.doi: 10.11889/j.0253-3219.2018.hjs.41.010202

• LOW ENERGY ACCELERATOR, RAY AND APPLICATIONS • Previous Articles     Next Articles

Influence factor of the detection limit of portable X-ray fluorescence instrument

DU Haiyan, LAI Wanchang, SHI Xiyu, CHEN Cheng, HU Yan, ZHAO Rui   

  1. Chengdu University of Technology, Chengdu 610059, China
  • Received:2016-12-14 Revised:2017-07-21 Online:2018-01-10 Published:2018-01-06
  • Supported by:
    Supported by the National 863 Program (No.2012AA06180303)

Abstract: Background: The study of the detection limit of X-ray fluorescence instrument is of great significance, as it is widely used in the analysis of low content elements because of its excellent performance. Purpose: To reduce the detection limit and measuring low content of metal elements more accurately, we provided reference for the choice of background subtraction methods and measurement conditions, etc. Methods: This paper studied the influence factors for the detection limit of the portable X-ray fluorescence instrument, such as background subtraction method, tube voltage and tube current. Blank sample-, linear-and Sterlinski-background subtraction methods were used to subtract the backgrounds and the suitable tube voltage and tube current range were tested. Certain corresponding relationship exists between detection limit and determination limit, so the determination limit was obtained using the detection limit, and the low content samples were analyzed. Results: Detection limit varies with tube voltage and tube current due to different background subtraction methods. The suitable tube voltage range of blank sample background subtraction is 28-40 kV and tube current range is 18-24mA, while that of linear background subtraction and Sterlinski background subtraction is 24-26 kV, 28-40 kV and 12-14 mA, 18-40 mA correspondingly. Conclusion: Blank sample background subtraction is the best, followed by Sterlinski background subtraction, while linear background subtraction is not suitable for the low content element analysis. Each background subtraction method has its suitable tube voltage and tube current range. When the content of elements is equal to the detection limit, the signal of the element detected is reliable, but it can not be used in quantitative analysis.

Key words: X-ray fluorescence instrument, Detection limit, Background subtraction, Tube voltage, Tube current

CLC Number: 

  • TL99