A portable energy dispersive X‐ray fluorescence (XRF) spectrometer furnished with an Rh X‐ray tube was evaluated for the determination of macronutrients and micronutrients in soybean leaves (Glycine max L.). XRF instrumental parameters were optimized in a univariate way, and emission intensities were measured for 60 s and under vacuum for macronutrients, and during 180 s, under air, and 305 μm Al/25.4 μm Ti filter, for micronutrients. Fresh and dried leaves were irradiated, and it was possible to identify P, K, Ca, S, Mn, Fe, Cu, and Zn Kα emission lines. For comparative purpose, the samples were also microwave assisted, digested and analyzed by inductively coupled plasma optical emission spectrometry. In general, linear correlations between K, Ca, Mn, Fe, Cu, and Zn concentrations in the tested samples and the corresponding portable XRF (pXRF) intensities were obtained. The linear correlation coefficients (R²) ranged from 0.42 to 0.86. In addition, the detection limits were suitable for plant nutrient diagnosis. It is demonstrated that pXRF is a simple and powerful tool for analysis of plant materials.

中文翻译：

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便携式X射线荧光光谱法直接测定体内条件下大豆叶片中的矿质营养素

对配备有Rh X射线管的便携式能量色散X射线荧光（XRF）光谱仪进行了测定，以确定大豆叶片中的大量营养素和微量营养素（Glycine maxL.）。XRF仪器参数以单变量方式进行了优化，对于大量营养物，在60 s和真空条件下测量了发射强度；对于空气，在180 s的空气中，对于微量营养物，测量了305μmAl / 25.4μmTi过滤器的发射强度。辐照新鲜和干燥的叶子，可以识别P，K，Ca，S，Mn，Fe，Cu和ZnKα发射线。为了进行比较，还对样品进行了微波辅助，消化和电感耦合等离子体发射光谱法的分析。通常，在测试样品中的K，Ca，Mn，Fe，Cu和Zn浓度与相应的便携式XRF（pXRF）强度之间具有线性关系。线性相关系数（R ²）介于0.42至0.86之间。此外，检出限适用于植物营养素的诊断。事实证明，pXRF是一种用于分析植物材料的简单而强大的工具。