Accurate and rapid quantification of actinides in highly radioactive solutions is critical for nuclear fuel reprocessing and waste management. This study presents a standardless X-ray fluorescence method applied to a hybrid k-edge densitometer (HKED) system at the Atalante facility at CEA Marcoule, eliminating the need for calibration standards by leveraging a fundamental parameters approach. The method uses one element as an internal reference to deduce the concentrations of other actinides, such as plutonium or neptunium, in liquid samples. The proposed approach combines a detailed geometrical and physical description of the HKED system, Monte Carlo simulations to model the apparent detection efficiency and Python-based spectral processing for peak integration and background correction. The method was validated on 19 spectra from three independent HKED systems (CEA Marcoule, JRC Karlsruhe, and IAEA), covering a wide range of U/Pu mass ratios. Results demonstrate expanded uncertainties below 2.5% for plutonium quantification when peak counting statistics are sufficient. The method is robust, adaptable to other actinides (e.g.: Np, Am), and can be extended to conventional XRF systems with internal standards. This work enhances the analytical capabilities of HKED systems by enabling fully standardless quantification, reducing reliance on mixed calibration solutions while maintaining high accuracy.
The elevated levels of heavy metals in traditional Chinese medicines (TCM) and the prevalent issue of counterfeiting present a substantial threat to human health. Laser-induced breakdown spectroscopy (LIBS) exhibits remarkable advantages in the rapid identification and quantitative analysis. Nevertheless, the disparities among various micro-regions of the laser-ablated samples unavoidably lead to spectral fluctuations, which significantly impact the performance of the model. To tackle this problem, this study proposes a spectral ordered arrangement image (SOAI): a single collected spectrum is placed at the center, and the four statistical values (Min, Q1, Q3, Max) of the multiple collected spectra are arranged on both sides to form an image. Subsequently, its features and corresponding spectral features are extracted to achieve data fusion. The results indicate that in the prediction of heavy metal contents in Astragali Radix, the fused model reduces the average absolute percentage error (MAPE) of Cu prediction by an average of 47.8%, and the limit of detection (LOD) interval is narrowed to [1.62, 3.57] ppm. In the origin identification, the overall accuracy rate of the model have been notably improved, with the recall rate of the Yunnan category reaching up to 100%. This outcome validates that the introduction of SOAI enhances the accuracy of LIBS in the detection of heavy metals in TCM and the analysis of origin traceability. It offers an effective solution from the perspective of data fusion to mitigate spectral fluctuations and further enhances the accuracy and practical application value of LIBS analysis of TCM.
Efficient ionization of arsenic (As), antimony (Sb) and bismuth (Bi) by ambient mass spectrometry (AMS) techniques facilitates direct analysis of complex samples since AMS provided less sample pretreatment, multiple ion detection modes and better sample compatibility. However, these elements normally need strict conditions to be atomized and ionized, such as inductively coupled plasma (ICP). In this work, efficient ionization of these elements was achieved by combining hydride generation (HG) with a facile corona discharge-induced micro-plasma of desorption atmospheric pressure chemical ionization (DAPCI) which was previously used for analysis of organic molecules. The three elements all exhibit characteristic mass spectra in either positive or negative ion mode. The method was featured by simplified manipulation, efficient ionization, and versatile ion species (e.g. AsO+, Sb+, SbO+, Bi+, BiO+, SbO2−) and detection modes (positive and negative). The influences of mass spectra by applied voltages, capillary voltages and tube lens voltages were investigated. The results showed that the detected species of these elements could be easily tuned in order to meet the detection requirements. The method also showed good signal stability, detection limits and linearity. The detection limits for As, Sb and Bi were 1.14 μg/L, 0.46 μg/L, and 0.35 μg/L respectively. The spike recovery was examined with four water samples, and the obtained spike recovery ranged from 85% to 118%. Considering the obvious advantages of HG-DAPCI-MS, the method may play an important role in sensitive and rapid analysis of various metals and/or metalloids in aqueous samples.
Reliable monitoring of dilution is essential for controlling clad quality during laser cladding, as excessive mixing between the deposited material and substrate can significantly affect the final coating properties. This study investigates plasma plume optical emission spectroscopy as an in-situ approach for estimating dilution during laser cladding of Stellite 6 powder on a steel substrate. Emission spectra were analyzed over a broad dilution range of approximately 20–70%, and quantitative spectral descriptors were extracted from the plasma emission spectra, including the integrated plasma emission intensity over 200–600 nm, the Cr I line intensity at 520.5 nm, and the near-ultraviolet emission intensity over 260–320 nm. These descriptors were correlated with measured dilution values to evaluate their capability for in-situ dilution monitoring. For highly diluted clads, the intensity ratio of the Fe emission line at 422 nm, mainly associated with the substrate, to the Cr emission line at 520 nm, associated with the powder, was also assessed. Reference spectra of the powder and substrate were independently acquired to assist in interpreting the process emission signals. The results indicate that, in the moderate dilution range of 20–45%, the total plasma emission intensity provides a strong correlation with dilution, with R2 values higher than 0.93. For dilution levels above 45%, where substrate-related atomic emissions become sufficiently detectable, the Fe/Cr emission intensity ratio offers a complementary indicator for dilution estimation, with an R2 value of approximately 0.82. The proposed spectroscopy-based approach provides a practical route toward in-situ monitoring of dilution and quality control in laser cladding processes.
Inductively Coupled Plasma Mass Spectrometry (ICP-MS) offers superior sensitivity, a wider linear range, and faster analysis compared to conventional analytical techniques. However, its practical application faces significant challenges, including complex sample matrices, isotopic complexities, and polyatomic ion interferences. While Collision Cell Technology (CCT) and Dynamic Reaction Cell Technology (DRC) aim to mitigate these interferences, they increase analytical complexity by requiring element-specific optimization. This study investigates interference mechanisms in trace silver analysis by ICP-MS, employing Kinetic Energy Discrimination to identify key parameters for interference removal and elucidate the interference reduction mechanism in the high helium flow rate KED mode. An advanced method for determining trace silver in geochemical samples is presented, achieving a detection limit of 0.005 μg/g. The method was successfully applied to various national standard materials, including soils, aquatic sediments, and rocks, demonstrating excellent agreement between measured and certified values. The method shows a Δlog C range of −0.042 to 0.05 and relative standard deviations from 1.43% to 6.32%. High helium flow rate KED-ICP-MS proves to be a simple, effective, and stable approach with considerable promise for future analytical applications.
