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Portable X-ray fluorescence spectrometry (pXRF) is an analytical technique that can be used for rapid and non-destructive analysis in the field. However, the testing accuracy and precision for trace elements are significantly affected by the matrix effect, which comes mainly from major elements that constitute most of the matrix of a sample. To solve this problem, many methods based on linear regression models have been proposed, but when extreme values or outliers occur, the application of these methods will be greatly affected. In this study, 16 certified reference materials were collected for pXRF analysis, and the major elements most closely related to the elements to be measured were employed as correction indicators to calibrate the analysis results through the application of multiple linear regression analysis. Some statistical parameters were calculated to evaluate the correction results. Compared with the calibration data obtained from simple linear regression analysis without taking major elements into account, those corrected by the new method were of higher quality, especially for elements of Co, Zn, Mo, Ta, Tl, Pb, Cd and Sn. The results show that the new method can effectively suppress the influence of the matrix effect.

Hexachlorocyclohexane(HCH) and Dichlorodiphenyltrichloroethane (DDT) are typical Organochlorine pesticides (OCPs), which were widely used in pest control and insect infestation in China. This study aimed at researching the concentration, potential sources and potential risk of HCH and DDT in Jilin University in Changchun, China. A total of 45 surface soil samples were collected from five land-use types in Jilin University campuses, the contents of were determined by Gas Chromatography and Mass Spectrometry (GC-MS) with Soxhlet extraction pretreatment technology. The overall HCHs existed the pollution in some campuses, while the DDTs were relatively low without pollution. Results of composition analysis showed that HCHs in campus soils mainly came from the mixed use of technical HCHs and lindane, and DDTs were mainly from the input of historical dicofol products. The potential health risks of HCHs and DDTs to campus populations were very low, while the potential ecological risks of HCHs and DDTs individual isomers should be paid attentions to.

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