The suppression of statistical fluctuations is crucial for the accurate qualitative and quantitative analysis of gamma-ray energy spectra. The nonlinear nature of these spectra in complex measurement environments presents a significant challenge to traditional smoothing methods, which are often constrained by their reliance on pre-defined models. To address this, support vector regression (SVR), an efficient supervised learning algorithm, is well-suited for managing nonlinear datasets. This paper proposes a generalized support vector regression (GSVR) model for gamma-ray spectrum smoothing, based on the principle of structural risk minimization. The performance of the proposed model was verified through a comparative study with traditional methods: multipoint moving average smoothing (MMAS), wavelet threshold denoising (WTDM), and noise-adjusted singular value decomposition (NASVD). Model performance was evaluated using a suite of metrics, including Smoothing Goodness (SG), Root Mean Square Error (RMSE), Energy Spectrum Distortion (ESD), and Signal-to-Noise Ratio (SNR). The comparison reveals that the proposed GSVR model demonstrates significant improvements. It achieves superior smoothing performance and better preservation of spectral peak shapes compared to all traditional methods evaluated. These results confirm the efficacy of the proposed model, offering an effective solution for smoothing gamma-ray energy spectra.

In thermoelectric cooling (TEC) systems for silicon drift detectors (SDDs) i energy-dispersive X-ray fluorescence (EDXRF) analyzers, analog current source control and pulse width modulation (PWMI control are commonly adopted. The former often suffers from limited dynamic response, while the latter inherently introduces es switching noise. Both approaches are susceptible to temperature fluctuations caused by ambient variations or changes in detector thermal load, which ultimately degrades energy resolution and induces peak position (energy scale) drift in the acquired spectra. To address these limitations, this study proposes a hybrid control scheme that combines PID-based analog current control with real-time digital baseline correction, The PID controller precisely regulates a low-noise current source to supply ripple-free driving current to the TEC, ensuring precise and stable temperature control of the SDD. Simultaneously, a baseline estimation and dynamic restoration algorithm. implemented in a field-programmable gate array (FPGA), actively suppresses signal baseline drift. Experimental results demonstrate that for the Mn-K-alpha, peak, the proposed scheme achieves an energy resolution (full width at half maximum. FWHM) of 128 eV, representing a 4 eV improvement compared to the conventional analog current source control method. During an 8-hour continuous measurement, the peak position drift of the Mn-K, line was constrained within 2 channels on a 4096-channel multichannel analyzer (MCA), significantly outperforming the conventional analog current source control method (the benchmark method). Therefore, the proposed hybrid control scheme effectively alleviates the effects of switching noise and environmental variations, significantly enhances the overall stability of EDXRF analyzers, and provides a robust solution for improving analytical precision.

The K-fluorescence technique exhibits superior monochromaticity and a uniform radiation field, making it highly suitable for elemental analysis. In this study, a K-fluorescence radiation device was employed to conduct X-ray fluorescence (XRF) analysis on five groups of ancient human bone samples spanning a temporal range of 5000 years. Preliminary identification of elemental compositions was achieved, enabling the revelation and inference of historical insights embedded within these ancient remains. During the experiment, the Si-PIN semiconductor detector was calibrated by using four standard radioactive sources with known energies, such as 55Fe, 109Cd, 57Co and 125Eu, and the detection efficiency of the detector at different energies was understood by Geant4 simulation to optimize the experimental settings. The results show that the characteristic peaks of calcium (Ca), iron (Fe), and strontium (Sr) appear in all the bone samples of different periods, and the energy spectra of the bone samples of the Ming Dynasty show anomalous heavy metal elements copper (Cu) and arsenic (As). With the historical background, the presence of heavy metal elements in the samples of the official eunuchs of the Jiajing period of the Ming Dynasty is analyzed to be related with the fact that the Ming Dynasty Emperor Shizong was fond of longevity and was obsessed with alchemy.

Accurate dosimetry is essential for ultrahigh dose-rate (UHDR, >40 Gy/s) irradiations in clinical radiotherapy (RT). Herein, we introduced a prototype of a micro-thin cylindrical ionization chamber (MC-IC) featuring an electrode distance of 0.2 mm, specifically designed for these beams. This study aimed to investigate the ion collection efficiency (ICE) of the MC-IC in high dose-rate and frequency (HDR&F) pulse X-ray beams. A detailed comparison was made among an empirical logistic model, the two-voltage analysis (TVA) method, and the Boag model. As anticipated, the MC-IC successfully measured a mean dose rate of up to 154.5 Gy/s with an ICE of 98.6 %. We found that the empirical logistic model is well-suited for the MC-IC, whereas the TVA method and Boag model exhibit an underestimation of ICE in HDR&F beams. Therefore, Boag Model 3 with a free-electron fraction of 0.5 < P < 0.6 and a modified TVA equation with a free-electron fraction of P = 0.6 must be considered. For the TVA method, a voltage ratio <= 2 is recommended. In conclusion, this study complemented and refined a dosimetric methodology for evaluating the collection efficiency correction factor for special ionization chambers.

Accurate measurement of high-flux synchrotron X-rays has become crucial for progress in plasma diagnostics and thermal nuclear fusion studies. A free-air ionization chamber and a low-current measurement system were developed to replicate high-flux monochromatic X-ray air kerma values. This system enables simultaneous measurement of ionization currents from the monitor chamber, free-air ionization chamber, and transfer detector, establishing a metrological standard for synchrotron radiation monochromatic X-ray flux. The correction factors of air attenuation, recombination loss and electron loss in the free-air ionization chamber were studied by means of a combination of experiment and theoretical simulation. Absolute measurements of air kerma were performed using monochromatic synchrotron X-rays in the energy ranges of (6-20) keV and (20-70) keV at the 4W1A beamline of the Beijing Synchrotron Radiation Facility (BSRF) and the BL13W1 beamline of the Shanghai Synchrotron Radiation Facility (SSRF), respectively. Through systematic uncertainty evaluation, the combined standard uncertainty of the air kerma measurements was determined to be 0.61%. By establishing the quantitative relationship between air kerma and photon flux, the monochromatic X-ray flux rates across the (6-70) keV energy range were derived with a combined standard uncertainty of 2.57%. The quantity transfer experiment of the transfer detector was carried out on the synchrotron radiation source, and the reliability of the measurement results was verified by indirect comparison with the calibration results of the PTB.

As a core tool in precision detection technology, the monochromaticity and flux stability of monoenergetic X-rays directly impact experimental accuracy in applications such as detector calibration. There is an urgent need to overcome the limitations of conventional radioisotope sources (fixed energy) and Bragg diffraction systems (low diffraction efficiency). Leveraging the unique properties of LiF(200) crystal-specifically its high reflectivity and low thermal expansion coefficient-this study constructed a Bragg diffraction-based monoenergetic X-ray apparatus. By adjusting the Bragg angle via a θ-2θ goniometer and performing energy-dispersive spectroscopy (4-48.32 keV) using a Fast-SDD detector, the system's performance was characterized. Geant4 simulations were employed to model the detector geometry, while standard K-series characteristic X-ray sources calibrated the energy linearity and energy resolution. Comprehensive analysis evaluated the apparatus' energy response, energy resolution, and monochromaticity. Results demonstrate that the system achieves: Monochromaticity < 2.2% within 4-48.32 keV, count rate of 3166 cps at 10 keV. This provides a viable bench-top alternative for optimizing high-precision X-ray analytical instrumentation and supporting synchrotron radiation experiments.

In the hydrometallurgical production of nickel ore, the real-time and accurate determination of nickel (Ni) content in leaching solutions is crucial for optimizing process parameters, ensuring leaching efficiency, and maximizing metal recovery. It plays a key role in achieving intelligent and efficient production. Energy Dispersive X-ray Fluorescence (EDXRF) spectroscopy, with its notable advantages of non-destructive testing, rapid response, and in-situ analysis capabilities, offers an ideal solution for online elemental detection in hydrometallurgical leaching solutions. However, achieving precise online measurement of Ni concentration in high-nickel leaching solutions via EDXRF relies fundamentally on establishing an accurate and reliable functional relationship between characteristic fluorescence counts and Ni concentration. Further optimization of the detection model tailored to the specific system of nickel ore hydrometallurgical leaching solutions remains necessary. This study addresses the requirements of actual industrial applications by designing a source-sample-detector Monte Carlo (MC) simulation model. The model employs a square pipeline configuration with the source and detector positioned on mutually perpendicular adjacent planes. A molybdenum (Mo) primary spectrum is used as the excitation source. Analysis of the MC model reveals that the characteristic fluorescence count decreases as the source-detector boundary distance increases. EDXRF experiments were conducted on Ni(NO3)(2) solutions simulating nickel ore leaching solutions. Through stepwise calibration of Ni concentrations ranging from 0 to 200 g & centerdot;L-1, the corresponding NiK alpha fluorescence counts were recorded. The results show a unimodal trend: the fluorescence count initially increases and then decreases with rising Ni concentration. To establish the functional relationship between NiK alpha characteristic fluorescence and concentration, the data were smoothed and fitted. Initially, based on the trend of the data, mathematical fitting was applied: a quadratic polynomial fit for the increasing and peak phases, and an exponential model for the decay phase. The average relative error between the fitted function curve and the original data was 6.81%. Subsequently, a single exponential decay product model was employed, reducing the average relative error to 3.72%. Finally, considering the experimental excitation setup and the actual source-sample-detector configuration, a semi-empirical composite exponential model was derived based on the fundamental equation of transmission X-ray fluorescence analysis. This model achieved an average relative error of only -1.093% compared to the original data, significantly outperforming the previous two models and more accurately characterizing the functional relationship between elemental concentration and fluorescence counts. The results demonstrate that the semi-empirical composite exponential model, grounded in the fundamental equation of transmission X-ray fluorescence analysis, more accurately represents the intrinsic relationship between characteristic fluorescence counts and Ni concentration in leaching solutions. The fitted results show higher consistency with the experimental data. This study provides methodological guidance for parameter optimization in real-time EDXRF detection of Ni leaching solutions, enhances the qualitative and quantitative analysis of hydrometallurgical leaching solutions, establishes a theoretical foundation for the broader application of this technology, and offers practical value for advancing online detection technology in hydrometallurgy, enabling precise process control and efficiency improvement.

Industrial wastewater discharge is an important factor causing heavy metal element Cd pollution in water systems. Improper discharge may cause serious environmental pollution. Long-term consumption of crops or aquatic organisms in Cd-contaminated environments will cause various diseases and cause serious harm to the body. Therefore, timely detection of the heavy metal element Cd content is very important for treating and discharging industrial wastewater. Compared with traditional detection methods, energy-dispersive X-ray fluorescence (EDXRF) analysis has the advantages of fast speed, no damage to samples, simple operation, and small instrument size. It is more suitable for application in industrial wastewater treatment sites to detect heavy metal elements in industrial wastewater rapidly. Detection provides a basis for the treatment of industrial wastewater. This article conducts research on factors affecting the on-site rapid detection of Cd element content in industrial wastewater using the EDXRF method. The detection object is untreated flowing industrial wastewater. In order not to affect the process flow, the wastewater sample will flow through a section of the processing pipeline, and the EDXRF detection device will be installed. Outside the processing pipeline, this paper deduces the mathematical model of X-ray fluorescence analysis when the pipeline is square and the X-ray source and detector are vertically located on two adjacent planes of the square pipeline. The simulation analyzes different pipeline geometric parameters and "source-sample" - Explore the influence of the geometric position of the element to be measured on the characteristic X-ray irradiation rate of Cd, verify the accuracy of the theoretical analysis through Monte Carlo method simulation, and obtain the optimal excitation-detection device and its optimized parameters for the square pipe sample. This article conducts MATLAB simulation research based on the established mathematical model. The industrial wastewater solution is set to have a Cd element concentration of 100 000 mu gmL(-1), the medium is an HNO3 solution with a concentration of 1.09 molL-1, and the incident light ray energy is set to 40 keV, which is brought into parameter calculation, the effects of pipe wall material, pipe wall thickness, detector height, and horizontal distance of the X-ray source on the changing trend of the characteristic X-ray intensity of the element Cd in the standard sample were obtained. At the same time, a Monte Carlo model was established to simulate and study the source outlet of the sample. The simulation study was conducted to investigate the influence of the horizontal distance from the source outlet to the sample side, collimator diameter, "source-sample" distance, "sample-detector" distance, detector height, pipe wall thickness, and pipe wall material on the net peak area and peak-to-background ratio of the Cd characteristic peak in the sample. It is found that the pipe wall thickness should be as thin as possible under allowable process conditions, and the commonly used pipe material is better to be polypropylene acid ester plastic. The "sample-detector" distance is 1 mm. The "source-sample" distance and detector height should be as small as possible under objective conditions, such as the device's geometric size and the device's fixing conditions. When the horizontal distance from the source outlet to the sample size is 2. 8 mm and the collimator diameter is 2 mm, the peak-to-background ratio and net peak area of the Cd characteristic peak will reach an optimal value.

In environmental gamma radioactivity measurements, the measurement of potassium, uranium, and thorium is crucial for strategic resource exploration, geological surveys, and environmental background investigations. This study focused on CeBr3 detector measurements and discovered that artificial radionuclides affected the intrinsic peaks and peak positions in the regions of interest for potassium, uranium, and thorium, resulting in offsets and distortions in the energy spectrum. Based on principal component analysis and linear regression, the study corrected the interference of artificial radionuclides in the measurements of potassium, uranium, and thorium. The results demonstrated that the peak offset was effectively corrected, with a maximum offset of 0.8 channels, compared to a maximum offset of 6.5 channels before correction. Additionally, correcting the peak area changes yielded better results, effectively reducing the errors in peak area calculations. Specifically, the error in peak area calculations was reduced from 10.52 % to 1.62 % for potassium, from 13.48 % to 1.79 % for uranium, and from 7.00 % to 4.96 % for thorium. The study successfully mitigated the peak position shifts and peak area variations caused by the counting contributions of artificial radionuclide 137Cs to the regions of interest for potassium, uranium, and thorium, thereby improving the accuracy of peak area calculations. The analytical method effectively addresses the issue of gamma energy spectrum offset and deformation, holding significant research significance and practical value in various applications, including aerial gamma energy spectrum measurements, environmental radioactivity measurements, geological exploration, and mineral investigations.

The full-energy peak efficiency allow radioactivity determination in gamma-ray spectrometry. In the determination of the full-energy efficiency, numerical calculation method has been widely used because of its accessibility, stability, and low computational cost. The current study presents a new direct numerical method that is based on the determining of the total efficiency and the escape efficiency. The method provides a detailed description of the generation and escape of secondary photons from the sensitive volume. It is applicable to any source-detector geometry and also considers the self-attenuation of the source matrix and the attenuation caused by absorber layers between the source and the sensitive volume. The results of comparing the new numerical method with experimental measurement for the point source test model demonstrate relative errors within -2.73 similar to 5.57 %, indicating the high reliability of this new method for sourceless efficiency calibration.

This paper presents an apparatus designed for the generation of polarized X-rays utilizing crystal Bragg diffraction techniques, which produces polarized X-rays energies within the range of 4-10 keV; facilitating the calibration of detection efficiency, energy resolution, polarization degree, and other parameters pertinent to polarized X-ray detectors. The apparatus comprises of a radiation source, a diffractive crystal, altrotating control mechanism, a detector and other components. High-precision generation of polarized X-rays can be achieved by dif-fracting through crystals with varying lattice constants at an angle of 45 degrees using an X-ray tube and a Bragg diffraction apparatus. Monte Carlo simulations were conducted to evaluate air absorption effects on X-rays at varying energy levels, revealing an optimal measurement dis-tance of 30 cm. Key metrics such as energy output, flux rate, energy resolution and mono-chromaticity for the generated polarized X-rays were evaluated through experimental measurements. The polarized X-ray flux rates were measured as: 4.135-10 ms at 4.59 kel 2.210-10 m25 at 6.39 kel, and 1.958-107 m(2)s at 10.029 keV. Monochromaticity values were: 1.48% at 4.59 kel; 0.96% at 6.39 kel, and 0.15% at 10.029 keV. The apparatus is ap-plicable to ground calibration of astronomical satellite payloads and detector development.

Abstract This paper introduces an integrated nuclear pulse generator aimed at simulating authentic radiation detection signals, allowing for the convenient calibration and testing of nuclear instruments without the need for radioactive sources. An innovative method is adopted, generating energy spectrum distributions via Monte Carlo simulation and deriving nuclear pulse waveforms using difference equations. This approach enables real-time computation of particle transport processes on a hardware platform, and generates pulse sequences that closely resemble the statistical characteristics of actual nuclear events. Compared to traditional nuclear signal generators, this new type of generator significantly enhances the flexibility and real-time capabilities of the equipment, as it no longer relies on pre-stored empirical data or simulation software to generate energy spectrum data. As a case for gamma-ray spectrometer detection, the signal waveforms and energy spectrum distributions produced closely match those obtained using a NaI scintillation detector in a lead chamber to detect a Cs-137 source.