Application of polarized EDXRF in geochemical sample analysis and comparison with WDXRF

Abstract

An EDXRF technique with polarized (P) excitation has been introduced into geochemical analysis research in China. Preliminary work on a Spectro X-Lab 2000 spectrometer showed that, in a total analysis time of 600 s per sample, over 30 elements can be quantified with detection limits of 0.5-30 µg g −1 , comparable to internationally published values. To test the capability of the method for practical sample analysis, about 100 unknown samples were measured. Also, a comparison of P-EDXRF and WDXRF with respect to results and performance was made. Both methods gave satisfactory results for over 30 elements. As P-EDXRF has the advantages of higher throughput, lower purchase price, lower running costs and full spectra collection, it is more competitive for geochemical mapping analysis whereas WDXRF is advantageous for more precise analysis. However, the relatively smaller detection area with a polarized target may present some problems when analyzing light elements in pressed pellet samples or when the samples are not homogeneous enough.

Determination of optimal metallic secondary target thickness, collimation, and exposure parameters for X‐ray tube‐based polarized EDXRF

“…For the secondary target thickness experiment, the secondary targets chosen to be examined were copper (Cu), molybdenum (Mo), and tin (Sn). Cu and Mo are two common metallic secondary targets, [1][2][3][4]9,14,15] while Sn was chosen to see if the trend was consistent at higher atomic numbers. The voltage was chosen to be 30 kV for the Cu trial, and 50 kV for the Mo and Sn, which allowed for significant X-ray production in the energy range of interest, while avoiding the production of higher energy X-rays that are much more likely to scatter.…”

“…One of the goals of performing an energy-dispersive X-ray fluorescence (EDXRF) experiment is to determine the concentrations of elements present within a sample. These experiments are usually performed to measure the trace elements in a sample, which can have large implications in various fields of research, such as geochemical analysis, [1,2] environmental science, [3] and medical physics. [4,5] Recent advances in EDXRF include using polarized X-rays to minimize the scatter reaching the detector, hence lowering the background noise and minimum detection limits (MDLs).…”

X-Ray Fluorescence Analysis in Biology and Medicine

“…Это более 30 элементов, содержание которых в организме обычно мало, но они участвуют в биохимических процессах и необходимы живым организмам. Среди них (в алфавитном порядке Z M): 35 Br, 26 Fe, 53…”

“…Это очень важно в случае применения в естественных условиях рентгенофлуоресцентного определения некоторых элементов в костях, тканях и отдельных органах. Динамичное развитие характерно для детекторов с термоэлектрическим охлаждением [11,15,16], РФА с полным внешним отражением (РФА с ПВО) [11,15,[17][18][19][20][21][22] и с поляризацией излучения [23][24][25][26][27][28]. При исследовании разнообразных биологических материалов широко применяются удобные портативные энергодисперсионные рентгенофлуоресцентные (ЭДРФА) спектрометры ряда фирм [29][30][31].…”

The scattering suppression of X‐rays with energy of 20–200 keV in spectrometers with Barkla polarizers

“…Zhan compares the analytical capabilities of EDPXRS and wave dispersion spectrometer (WDS). On EDPXRS Spectro X‐Lab‐2000, 52 elements are determined in geochemical samples, 30 of them with thresholds of 0.5–30 ppm.…”