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X-ray fluorescence spectrometry (XRF) has been widely used for multi-element determination in various samples. However, when trace level determination is required, separation and preconcentration procedures are often used as a step before detection to avoid or reduce interferences and to increase sensitivity. Liquid-phase extraction (LPE) is one of the most well-known and applied pretreatment techniques associated with atomic spectrometry due to its simplicity, speed, and ease of automation. A review of methods involving LPE combined with XRF is presented. Methods described in the literature are discussed, involving conventional LPE and the three main categories of liquid-phase microextraction (LPME): single-drop microextraction (SDME), dispersive liquid–liquid microextraction (DLLME), and hollow fiber liquid-phase microextraction (HF-LPME). Characteristics of the methods are presented, considering experimental aspects, analytical features, advantages, and disadvantages. In addition, trends in the association between LPME techniques and XRF are presented. [ABSTRACT FROM AUTHOR]

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The study is to provide a detailed physical and chemical characterization of particles collected in the ironmaking process, including a bunker system, a cast house and a pulverized coal feeding system. Using gravimetric, scanning electron microscope coupled with energy dispersive X-ray spectrometry (SEM-EDS), X-ray fluorescence spectrometry (XRF), inductively coupled plasma optical emission spectrometry (ICP-OES) analyses, the size distribution, morphology, elemental composition and emission factor of particles were investigated. The contribution rates of cast house for emission factors of total suspended particulates (TSP), PM10 and PM2.5 are the largest, 57.0%, 75.5% and 83.3%, respectively. SEM-EDS analysis indicated that cast house particle shapes are mainly formed by polymerization from spherical particles and ultrafine particles, whose main component is Fe. But, the particles of the bunker system or the pulverized coal feeding system are mainly the large ones of irregular block or powder particles and the main component is carbon. The highest content of the element in particles of the bunker system and cast house is Fe, followed by C, Si, Ca and Al. The main elements of particles in the pulverized coal feeding system are C, Si, Al and Ca, and their contents are 63.6%, 7.83%, 3.07% and 1.47%, respectively. [ABSTRACT FROM AUTHOR]

X-ray fluorescence spectrometry was used to determine essential and toxic elements in tea leaves. Quantitative measurements were obtained for K, Mg, Cu, Zn, As, Sr, Fe, Co, Ca, P, S, Pb, Rb, and Mn. Pearson's product moment correlation coefficient with principal component analysis and hierarchical clustering analysis were performed to investigating the relationships between essential and nonessential elements in the dry herbal mass. From multivariate statistical analysis, Ca, Fe, P, Zn, and Mn were found to have strong positive correlations. While principal component analysis demonstrates that tea leaves were dominated by Fe and Cl in the first principal component, Pb and As were in the second principal component with cumulative variability of 84.4%. However, hierarchical clustering analysis indicated the presence of a cluster of four essential elements, one cluster containing toxic and essential elements, and one cluster composed of toxic elements. The results of this study improve understanding of the correlation between essential and toxic elements in biological samples such as tea leaves. [ABSTRACT FROM AUTHOR]

Electrodeposition is as an attractive technique for sample preparation in X-ray fluorescence spectrometry with advantages of low cost, high sensitivity, and minimal interferences. A simple and efficient electrolysis process for the preconcentration of selenium(IV) and tellurium(IV) is reported. The analytes were electrodeposited on a polished substrate of high purity copper, which was rinsed with deionized water, dried, and directly analyzed by x-ray fluorescence. The influence of concomitant metal ions, electrodeposition voltage, pH, and electrolyte concentration on the deposition efficiency was investigated. The presence of lead(II) was shown to improve the efficiency and reproducibility of the deposition of selenium(IV). Moreover, the results showed that the method provided superior tolerance to various coexisting ions. The reproducibility of determination was 2.4% for selenium(IV) and 1.9% for tellurium(IV) (n = 7). The detection limits for the measurement of selenium(IV) and tellurium(IV) were 0.44 and 0.57 µg L−1, respectively. The method was validated by analyzing certified reference materials and applied to the determination of trace selenium and tellurium in environmental water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Total reflection X‐ray fluorescence analysis (TXRF) is a special method of energy‐dispersive X‐ray fluorescence analysis extending EDXRF to the ultra trace element level. The achievable detection limits depend on the excitation source and are in the range of picograms to femtograms. Only small amounts of sample are required and the quantification by adding one element as an internal standard is easy as thin film approximation is valid. In this article, the recent advances in TXRF are reviewed with over 80 references. The principles, advantages, instrumentation, improvements with X‐ray optics, synchrotron radiation as excitation sources as well as various fields of application, wafer surface analysis, depth profiling, absorption spectroscopy, medical samples, biological samples, environmental monitoring, archeological and polymer samples are described. Related techniques are also mentioned and discussed. [ABSTRACT FROM AUTHOR]

The results of a study of the elemental and ionic composition of the ambient aerosol in and around Antwerp are presented. Four sampling campaigns were performed, covering all seasons. The samples were obtained by filtration and impaction methods. Subsequently, the filters were analyzed by X-ray fluorescence spectrometry for elements, and the impactor substrates were leached with water and analyzed by ion chromatography for ions. When comparing the results of the chemical analysis with the meteorological information, it was found that the concentration of certain elements and ions in aerosol samples was affected considerably by the location of the sampling site and by the meteorological conditions. In relatively less polluted places like small towns and rural regions around Antwerp, the concentrations of some elements and ions showed qualitatively a positive or negative correlation in their time variations with the amount of precipitation. Hence, we suppose that in the first case these elements and ions are contained mainly in the more hygroscopic fraction (the most apparent is the behavior of Na and Cl), and that in the second case, the elements are mainly present in the less hygroscopic fraction of the ambient aerosol. However, this behavior of the elements and ions may be different for various particle size ranges. In the highly urbanized and industrial sites close to the central and industrial parts of Antwerp, these correlations were not found. This could be connected with the high and variable local aerosol generation rate, when only heavy rains are able to provide a sufficient removal of the aerosols from the atmosphere. [ABSTRACT FROM AUTHOR]

X-ray fluorescence (XRF) spectrometry is a nondestructive, rapid, simultaneous multi-element analytical methodology for solid or liquid samples. Its applications are broad and XRF spectra cover most elements, with a dynamic range from 100% down to the µg/g level. X-ray fluorescence is a well-established laboratory-based method, but it is also one of the few atomic spectrometric techniques that can be used for field portable instrumentation. In this manuscript, the recent advances in portable XRF spectrometry are reviewed with 80 references. The principles and instrumentation are briefly discussed, and many applications of the technique are described, including the analysis of soils, sediments, waters, liquid wastes, air, dust, archaeological artifacts, works of art, paint, metals, alloys, minerals, and forensic samples. Portable XRF is especially suitable for fast screening applications when the specific analytes of interest are unknown. The technique does not have accuracy and limit of detection (LOD) values comparable to those of conventional laboratory-based atomic spectrometric techniques, such as inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, or electrothermal atomization atomic absorption spectrometry, but it finds its niche in its portability. [ABSTRACT FROM AUTHOR]