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Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Some methods of X-ray spectral analysis used by Russian researchers to determine the elemental composition of medicinal plants are considered. The review focuses on the articles published in Russian journals over the past 20 years. Researchers utilize wavelength dispersive X-ray fluorescence (WDXRF), energy dispersive XRF (EDXRF), synchrotron radiation XRF (SRXRF), and total reflection XRF (TXRF) spectrometry; electron probe microanalysis, and scanning electron microscopy to analyze both macro- and microelement contents in medicinal plants. The simultaneous determination of macro- and microelements, coupled with nondestructive sample preparation, makes XRF spectrometry an attractive method for identifying and monitoring the chemical composition of plants, especially those employed in medical practice. Most published studies provide comprehensive information on sample preparation and measurement procedures, present metrological evaluations, and discuss the results obtained. However, some publications lack essential methodological details, and misprints in the presented analytical data occur. [ABSTRACT FROM AUTHOR]

The experiment aimed to establish a monochromatic wavelength excitation-energy dispersive X-ray fluorescence spectrometry (MW-EDXRF) method for determining iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in feed and feed raw materials. Selected common feeds such as fish meal, soybean meal, soybeans, chickpeas, barley, sorghum, dry corn distiller's grains, cat food, and dog food as samples, used MW-EDXRF for measurement. After optimizing the pretreatment and analysis conditions, the linearity, accuracy and precision tests were carried out. The results showed that the linear regression coefficient R² of the standard curves established for the above four elements was greater than 0.99, and the detection limits (LOD) were 0.411, 0.404, 0.408, 0.387 mg/kg, respectively. The relative standard deviation (RSD) of the measurement was within 0.5 %. The measured values of the quality control samples are within the standard value range of the certificate. The study indicates that the method established in the experiment is simple, fast, reliable, and accurate, and is suitable for the detection of heavy metals in feed and feed raw materials. [ABSTRACT FROM AUTHOR]

Society's need for safe flame‐retardant technologies in passive fire protection is undeniable. To address this concern, this paper presents an experimental investigation of the fire‐retardant properties of slash pine wood treated with banana plant pseudostem sap, obtained from a cultivated banana plant variety widely grown in Brazil. The natural sap extract was characterized through X‐Ray Fluorescence spectrometry and Fourier Transform Infrared Spectroscopy techniques, revealing the presence of key components, including water, potassium chloride, sodium chloride, sodium silicate, calcium phosphate, sodium phosphate, lignin and tannins. The authors explored different treatment parameters, including various sap impregnation times, number of impregnations and use of natural versus various levels of concentrated sap. First, a horizontal burning test, similar test to UL 94 HB, was used to obtain an initial assessment of the suitability of sap as a flame retardant for slash pine wood. Subsequently, the Mass Loss Calorimeter equipment with thermopile attachment described in ISO 13927:2015 was used to measure various heat release rate parameters. The findings suggest that reducing the water content in sap and increasing the number of repeat treatments results in a more effective treatment for slash pine wood. More specifically, the results indicate that the most efficient treatment involves three impregnations with high‐concentration (1/10 volume reduction) sap. Future work to improve the efficacy of the concentrated sap impregnation process could explore the use of pressure treatment instead of soaking. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The composition of solid solutions in the KNd(SO4)2·H2O–SrSO4·0.5H2O system, synthesized from aqueous solutions of KCl, NdCl3, SrCl2, and H2SO4, was studied by X-ray fluorescence spectrometry. Coefficients of calibration dependences for intensity vs. element concentrations were calculated for Nd, Sr, and K by the least-squares technique. A linear approximation function was used in determining potassium and a parabolic approximation function was recommended in determining neodymium and strontium. The obtained dependences are characterized by low (<1%) relative approximation errors. In the analytical ranges (wt %) for K 0.863−8.892, Sr 8.41−38.03, and Nd 5.296−29.30, the standard deviations were 0.012−0.028, 0.008−0.098, and 0.05−0.27 respectively. [ABSTRACT FROM AUTHOR]

The major challenge in plant mineral nutrition monitoring has been determining the concentrations of various elements in tissues. This is done to evaluate the availability and sufficiency of essential and beneficial elements and prevent elemental toxicities. Here, we present a rapid, safe, and accurate procedure for the simultaneous multi-elemental analysis using wavelength-dispersive X-ray fluorescence spectrometry (WDXRF) coupled with an isotope ratio mass spectrometer (EA-IRMS). Both techniques' applicability, accuracy, and precision were verified by analyzing International Plant-analytical Exchange-Standard Reference Materials (IPE-SRMs). In both methods, there was an excellent agreement of experimental and certified values within allowable standard deviation in the range of 10 ppm to 5% (in most cases R² > 0.99). Likewise, there were no significant differences in measured and certified values at a 99% confidence level. There was still decent agreement for concentrations of less than 10 ppm for most but not all elements. The accuracy and versatility of multi-element analyses through WDXRF and EA-IRMS prove that these techniques offer relevant advantages in speed and analytical costs per element. Both methods can be handy in providing immediate analytical results, as sample digestion is not required. Hence, time-critical plant nutrition monitoring and appropriate management can easily be achieved and implemented. Additionally, both techniques can quantify elements that are otherwise tedious to determine by other analytical methods (e.g. P, S, Sr, Cl, Ti) but are needed in understanding the processes of plant biology, ionomics, and elemental tolerance. [ABSTRACT FROM AUTHOR]

Copyright of Food Science & Technology & Economy is the property of Grain Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This chapter (Principles and Practice of X‐Ray Fluorescence Spectrometry – 1: Fundamentals of XRF and Matrix Corrections) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of the Handbook of Silicate Rock Analysis (P. J. Potts, 1987, Blackie, Glasgow). Chapter 6, Part 1 (from Section 2 of the handbook dealing with techniques for the determination of major and trace elements) considers the fundamentals of XRF spectrometry and matrix corrections in detail. Part 2 deals with wavelength dispersive and energy dispersive instrumentation. Following an introduction dealing with the analytical characteristics of XRF spectrometry, Part 1 continues with a detailed consideration of the origin and excitation of X‐ray spectra. Sub‐chapters that tackle the interaction of X‐rays with matter and the matrix effect in geological materials follow this. Part 1 is concluded with a mathematical treatment of the correction of absorption‐enhancement effects. [ABSTRACT FROM AUTHOR]

In the field of forensic science identification, geochemical-related materials such as soils and rocks were important sources of material evidence. In actual case analysis, the information provided by material evidence often pointed to unknown areas. Predicting the source of material evidence was an extremely challenging task when the location of the crime scene was not clear. To address the uncertainty of geochemical material evidence information, a dataset including physicochemical properties and geographic information such as mineral composition, element content, and geographical location was established. By comparing the sample information from the crime scene, the source of the material evidence samples could be quickly determined, providing strong technical and evidentiary support for case investigation. Surface soil samples (0−10cm) were collected from urban areas in Shenyang City, Liaoning Province, and X-ray fluorescence spectrometry (XRF) and X-ray powder diffraction (XRD) were applied to test and analyze 15 elements (SiO2, Al2O3, CaO, K2O, Na2O, MgO, TFe2O3, Ti, Mn, Ba, P, Zr, Cu, Zn and Pb) and mineral components in the soil material evidence samples. With the help of MapGIS software, element content distribution maps were drawn to explore the characteristics and influencing factors of element distribution in the study area. Principal component analysis (PCA) was used to classify and identify soil samples from three study areas. The results indicated that: (1) through urban geological mapping, accurate and intuitive element content distribution maps can be obtained, allowing court workers to compare the elemental characteristics of soil samples and trace the source of material evidence. (2) The soil material evidence samples from Shenyang were mainly composed of quartz, feldspar, montmorillonite, and illite (88.0%−98.0%). The XRD diffraction bar thermal map facilitated court workers to conduct comparative analysis of large amounts of data. (3) Based on PCA, a dimensionality reduction analysis of 15 elements from three study areas was conducted, and significant regional discrimination of soil samples from the three study areas was achieved within a 95% confidence interval (Group 1: F1<0, F2<0; Group 2: F1>0, F2>0; Group 3: F1>0, F2<0). (4) There were significant differences in chlorite, tremolite, kaolinite, calcite, and dolomite among soil samples from the three study areas, further supporting the accuracy of PCA classification. In summary, the combined application of XRF and XRD technology could be used to effectively distinguish soil material evidence samples from different areas within the city, providing directed research areas for soil material evidence traceability investigation and important clues to narrow down the investigation scope. [ABSTRACT FROM AUTHOR]

Optically stimulated luminescence (OSL) dating includes the measurement of the equivalent dose and the environmental dose rate. The accurate determination of uranium, thorium and potassium is an important step in ensuring the accurate calculation of the environmental dose rate. The commonly used measurement method is the combination of inductively coupled plasma-mass spectrometry/optical emission spectroscopy (ICP-MS/OES), but the determination of uranium, thorium and potassium can not be done at the same time, and the measurement time is long. In the research, two methods of ICP-MS and X-ray fluorescence spectrometry (XRF) measuring the three elements were compared. Using ICP-MS analysis, electronic dilution was used to reduce the potassium ions entering the detector, so that potassium ions were in the same order of magnitude as uranium and thorium ions. Thus, the simultaneous analysis of high content potassium and low content uranium and thorium was achieved. The detection limits for uranium, thorium, and potassium were 6.38ng/L, 8.52ng/L, and 926ng/L, respectively. The effects of closed acid dissolution method and open acid dissolution method on the determination of uranium, thorium, and potassium by ICP-MS method were studied. The two dissolution methods dissolved 10 sediment and soil standard substances, and the results of uranium, thorium, and potassium determination were accurate and reliable, with no significant difference in relative error, ranging from 0 to 9.33%. However, the operation of open acid dissolution method was simpler, and the sample processing time (about 9h) was much shorter than the closed acid dissolution method (about 60h). Therefore, open acid dissolution was selected to dissolve the sample in ICP-MS method. By XRF analysis, the relative errors for the determination of uranium, thorium and potassium in standard materials by pressed-powder pellets method were 4.78%−16.2%, 1.20%−13.3% and 0.00%−5.67%, respectively. ICP-MS and XRF were used to determine 20 sediment samples from Bohai Bay, and the relative deviation of the environmental dose rate was less than 6%. XRF has advantages in the measurement of potassium and is more suitable for luminescent samples with high potassium content. The ICP-MS method has a lower detection limit, and higher precision and accuracy for the determination of uranium and thorium. For ultra trace samples, this method provides more accurate measurement results. [ABSTRACT FROM AUTHOR]

This work describes a two-stage technique of X-ray fluorescence (XRF) analysis of rare earth niobates. A comparison between the two approaches revealed that the Fundamental Parameters Method (FPM) can be employed for a rapid preliminary assessment of the composition of the resulting material and the construction of calibration curves can be used to determine the contents of the major elements with precision. The results of the relative standard deviation (RSD) for FPM were no more than 7%, while the approach to construct calibration curves had an RSD of no more than 1%. Calibration samples were prepared using the same synthesis method as the study samples to construct the calibration curves. The possibility of constructing calibration dependencies using mixtures of oxides was assessed, but this approach could not provide the desired accuracy. The obtained results have been shown to have a good correlation with inductively coupled plasma optical emission spectrometry. The developed technique enables the determination of the major components in niobates containing two and three rare earth elements, which are used as optical materials and medium-entropy ceramics. [ABSTRACT FROM AUTHOR]

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In addition to larger collections of Mapuche artifacts acquired during the prolonged stays of Milan Stuchlík (1932-1980) and Václav Šolc (1919-1995) in Araucania, Chile, during the 1960s and 1970s, the Náprstek Museum also houses two smaller collections of Mapuche jewellery. The first four jewels were purchased from Eduard Tauer in 1896 and two more pieces were acquired in 2024 from the estate of diplomat Stanislav Svoboda (1926-2015). This article serves as the first introduction to the Mapuche jewellery collection originating from these two collectors. It examines the use, age, and material composition of the artifacts and the collectors responsible for the acquisitions and compares this collection with the Mapuche jewellery collection in the Weltmuseum Vienna. Furthermore, the article outlines potential avenues for further research. [ABSTRACT FROM AUTHOR]

Monochromatic excitation X-ray fluorescence (ME-XRF) spectrometry is a novel technique for trace element analysis, characterized by its simplicity, rapidity, and low cost. The objective of this study was to evaluate the applicability of ME-XRF technique for the measurement of thallium in biological samples. Acute and subacute thallium poisoning experiments were conducted to simulate various scenarios, with blood, urine, and 10 distinct organs collected. Detection was initially performed using ME-XRF technique, followed by validation with inductively coupled plasma mass spectrometry (ICP-MS). Excellent agreement between ME-XRF and ICP-MS values was demonstrated by means of paired sample t-tests and intraclass correlation coefficients. Subsequently, the practical implementation of the proposed technique was demonstrated through an actual case study. In conclusion, this study validates ME-XRF as a suitable alternative to ICP-MS for the measurement of trace heavy metals in biological samples. These efforts promote the development of simpler and faster techniques for heavy metal detection, thereby presenting novel avenues for the prevention and diagnosis of heavy metal poisoning. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Arsenic (As) and fluoride (F) are two typical harmful elements with high concentrations in Yangbajing high-temperature geothermal water, and the release of As and F from geothermal sources to the surface or near-surface environment can be further promoted and accelerated through geothermal development, causing surface water and soil environmental pollution. To understand the enrichment mechanism of As and F in the geothermal water body, hydrochemical characteristics as well as the concentrations of As and F were investigated by water quality analyzer, atomic fluorescence spectrometry, X-ray fluorescence spectrometry, and ion selective electrode method. The results indicate that the main sources of As and F in geothermal water and surface soil are water-rock leaching interaction. Unique hydrochemical characteristics (Na-HCO3 ∙Cl) with high concentration Na+ (reach to 445.5mg/L), poor in Ca2+ (as low as 3.31mg/L), and high pH (7.87−9.42) provided a favourable condition for the leaching of As and F in water. Affected by water vapor evaporation, the concentrations of As and F in hot spring water were higher than those in geothermal water and reached 6.50mg/L and 17.89mg/L, respectively. Notably, the total concentrations of As and F in waters were significantly higher than the maximum allowable emission concentrations for harmful components (0.5mg/L for As, and 10mg/L for F) in the Geothermal Resources Assessment Method (DZ40—85). Moreover, the concentrations of total As and F in the soils were 79.50−99.08mg/kg and 1162.70−1285.10mg/kg, respectively, significantly higher than the background values in Xizang soil. [ABSTRACT FROM AUTHOR]

Preconcentration of strontium and barium as complexes with 11 organic reagents by coprecipitation with organic co-precipitants for their subsequent determination by X-ray fluorescence spectrometry is studied. The most effective systems turned out to be those included reagents from bisazosubstituted chromotropic acids, nitchromazo and chlorophosphonazo III. Complexes of these metals are virtually quantitatively coprecipitated as pairs with cations of the brilliant green dye, of the collector is an associate of an excess of the analytical reagent with cations of this dye. It is shown that the additional use of polyvinyl butyral as an indifferent co-precipitant ensures not only the almost complete extraction of these elements from solutions, but also the preparation of emitter concentrates suitable for X-ray fluorescence measurements using the standard-background technique. High efficiency allows, under optimal conditions, the achievement of very low limits of detection (IUPAC): 0.03 μg/mL Sr and 0.19 μg/mL Ba, even in working with small samples (by volume). [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The iron sand around Mt. Aburayama (Fukuoka, Japan), where various ancient iron‐making sites are located, was investigated to establish a research infrastructure for identification of the raw material used in the archeological iron artifacts excavated from this area. Iron sand samples were magnetically collected from the rivers flowing in this area and nearby outcrop soil. The samples were qualitatively analyzed using Mössbauer spectroscopy and x‐ray diffractometry to identify the minerals present inside them. Additionally, the elemental concentrations in these samples were determined using x‐ray fluorescence spectrometry. The iron sand samples were characterized by comparing them with those from other Japanese regions using scatter diagrams developed based on the elemental concentrations in the samples. The scatter diagrams showed clear distinctions between the iron sand samples from the Mt. Aburayama area and other Japanese regions. These diagrams may enable us to clarify the relationship between the iron sand and archeological iron artifacts found in the vicinity of Mt. Aburayama. [ABSTRACT FROM AUTHOR]

The porphyrite-type iron deposit in Ningwu Basin is an important source of iron resources in China, and the premise for the efficient and comprehensive utilization of its complex tailings is a thorough understanding of their mineral processing characteristics. In order to provide a reference for the comprehensive utilization of porphyrite-type iron deposit tailings in Ningwu Basin, the process mineralogy characteristics were explored by using the combined methods of X-ray fluorescence spectrometry (XRF), inductively coupled plasma-mass spectrometry (ICP-MS), X-ray diffractometry (XRD), and TESCAN integrated mineral analyzer (TIMA). The results show that the tailings are composed of mainly Si, Fe and Al. The mineral compositions are mainly albite, hematite, magnetite and quartz. Silicon mainly occurs in quartz and albite, whereas Fe mainly occurs in hematite/magnetite. The tailings have a fine particle size and low mineral liberation degree. Compared to other types of iron deposit tailings in China, these tailings are characterized by a high content of Al and a relatively high proportion of pyrite. [ABSTRACT FROM AUTHOR]

An overview of publications dedicated to the application of various X-ray fluorescence techniques for investigating the chemical composition of ancient ceramics and clays is presented. Examples of conventional wavelength dispersive and energy dispersive X-ray fluorescence spectrometers, portable X-ray analyzers, spectrometers with polycapillary optics (micro X-ray fluorescence spectrometry), and total reflection geometry are considered. Although X-ray fluorescence serves as the analytical signal in all cases, the listed X‑ray fluorescence techniques differ in the range of analytes, methods of sample preparation, and methods for calculating element concentrations. The author experience in applying the described techniques of X-ray fluorescence spectrometry to a comprehensive study of archaeological materials from the Stone Age for the historical reconstruction of economic activities in the Baikal Siberia population is also discussed. [ABSTRACT FROM AUTHOR]

As a new product, the silver porcelain cup meets people’s characteristic needs and is favored by the market because of its diverse patterns and styles. X-ray fluorescence spectrometry, ICP spectrometry, potentiometric titration, and photomicrography system were used to test and observe the silver porcelain cup in the experiment. The results of the study show that the X-ray fluorescence spectrometry method makes it difficult to obtain accurate detection results due to the thin silver layer on the silver porcelain cup. Potentiometric titration can be opted for detection. Lead is often detected in silver porcelain cups. To reduce the lead content in products, it is recommended to use lead-free glazes. [ABSTRACT FROM AUTHOR]

Copyright of Food Science & Technology & Economy is the property of Grain Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The chemical forms and content of phosphorus in sediments are the important basis for exploring bioavailability, migration, and transformation of phosphorus in sediments accurately. To assess and evaluate phosphorous pollution from a phosphate mine, the phosphorus chemical forms in the sediment were determined by a suggested combined method and studied by the phosphorus classification method. The results show that the total phosphorus content all reached the lowest level of ecotoxic effect, and 56.7% of samples reached the serious level of ecotoxic effect. Therefore, it is suggested to strengthen the monitoring and assessment of river pollutants in phosphate mining areas. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: China is the world’s largest aluminum producer and consumer. With the development of China’s aluminum industry, bauxite resources are consumed continuously and highly dependent on imports. In 2019, China’s imports exceeded 100 million tons of bauxite, with an increase of 21.9%, and in 2020, imports reached a record high of 110 million tons, and dependency on importing bauxite is increasing from 5% in 2001 to 50%. Therefore, high-sulfur bauxite becomes an important new resource. A large number of high-grade high sulfur sedimentary bauxite has been found in China. However, due to the high sulfur content (S>0.7%) in high sulfur sedimentary bauxite, which seriously affects the subsequent aluminum extraction process, it has not been used in industry. If it can be developed and utilized in industry, it is of great significance to the development of the aluminum industry. OBJECTIVES: In order to clarify the ore properties and the possible industrialization technical indicators of sedimentary bauxite in Western Guangxi. METHODS: X-ray fluorescence spectroscopy, polarizing microscope, X-ray diffraction and scanning electron microscopy were applied to investigate composition and properties of the sedimentary bauxite ore, which provided important reference data for the development of this type of bauxite. RESULTS: (1) The content of Al2O3 in the ore is 64.21% and the content of S is 5.13%. According to the classification of the bauxite industrial index quality, the ore belongs to high sulfur deposit type bauxite. (2) The aluminum minerals in the ore are mainly diaspore and chlorite, with fine crystal size, oolitic aggregate form and smooth surface for diaspora. The main iron minerals are pyrite, hematite and limonite. The pyrite exists in the form of euhedral, semi-euhedral and allotriomorphic crystals, and the size of crystal particles is different. Some of the coarse-grained and medium-grained pyrites have a particle size of more than hundreds of microns. Compared with the accumulated bauxite in the same source layer, the biggest difference of sedimentary bauxite in Western Guangxi is that it contains an amount of pyrite. (3) Diaspore and pyrite are the main useful minerals of bauxite, there are differences in the distribution between the two minerals in the ore. The difference is conducive to the use of crushing and grinding methods to dissociate mineral monomers, and then select appropriate mineral processing methods to separate pyrite. CONCLUSIONS: It is possible to dissociate the main minerals in the high sulfur sedimentary bauxite by crushing and grinding. Based on previous experiments on high-sulfur bauxite, the high-sulfur problem of the sedimentary bauxite can be effectively separated from pyrite by mineral processing. Monomer separation can be achieved by crushing and grinding, with removal of the pyrite by flotation by a mineral processing reagent system. Thus, the aluminum-containing minerals after floating sulfur meet the requirements of alumina extraction and feeding in the next step. [ABSTRACT FROM AUTHOR]

This review covers characteristics and potential applications of various versions of the X-ray fluorescence (XRF) spectrometry for analyzing both liquid and solid samples. Particular emphasis is given to research published within the past decade, as information on XRF's previous applications can be found in earlier reviews and monographs. The results of experiments on determining fundamental atomic parameters, such as mass absorption coefficients, fluorescence yields, transition probabilities for the emission of specific lines of elements, and nonradiative transition probabilities. Additionally, the review addresses the capabilities of newly designed models of XRF spectrometers developed in recent years. The application of total reflection X-ray fluorescence spectrometry for diverse samples is examined in greater detail. Furthermore, the document presents data on the utilization of XRF in investigating nanoparticles of some typical materials. These particles exhibit qualitatively novel properties and have become a focal point of nanotechnology, an area rapidly developing in the last few decades. [ABSTRACT FROM AUTHOR]

Background: Understanding the elements that support cataract development and searching for available therapeutic methods is essential for scientific and social interest. For that purpose, the role of trace elements has been investigated in this study to better understand the development of cataracts in dogs. Objective: The aim of this study was to evaluate the ratio of the major and trace elements by X-ray fluorescence spectrometry in dog cataract lenses to contribute to diagnostic, non-surgical, and ophthalmological preventive data. Methods: A single lens with a cataract from each of a total of 88 dogs (cataract group) and a healthy lens from each of 6 dogs (control group) were evaluated. The elements calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), magnesium (Mg), manganese (Mn), and potassium (K) were analyzed by energy dispersive X-ray fluorescence and X-ray microfluorescence. Results: The results indicated an increase of Ca, Fe, Cu, and Zn, in association with the reabsorption mechanism of hypermature cataracts. Conclusions: The ratio of elements Ca, Fe, Cu, and Zn was different in cataract lenses than in healthy lenses, and our results may support the development of therapeutic strategies for cataracts in dogs. The Ca concentrations were distinct in the cataract development stages, and the Fe concentration was relatively higher in males when compared to females. Finally, this research stands out with a particular contribution to the understanding of both cataract formation and prevention. [ABSTRACT FROM AUTHOR]

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]

This study aimed at determining the concentrations of rare earth elements (REEs) in coal and coal fly ash (CFA) from three coal mines in Tanzania: Kiwira, Ngaka and Rukwa. The goal was to assess if these resources could be commercially viable for extracting REEs. Coal and CFA samples were analysed using X-ray fluorescence (XRF) spectrometry and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The total concentrations of REEs in the coal samples ranged from 89.48 parts per million (ppm) to 196.30 ppm, while in CFA samples, ranged from 362.55 ppm to 475.77 ppm. Computed percentage of critical REEs (REYdef, rel%) and outlook coefficient (Coutl) values ranged from 27.41% to 50.74% and 0.62 to 2.00, respectively. Based on the evaluation criteria proposed for assessing coal and coal ash as sources of REEs, the results suggest that the studied coal and CFA samples have the potential to be used as sources of REEs for economic development. These findings have important implications for the Tanzanian government and other relevant authorities, as they provide valuable insights into the feasibility of investing in the coal and coal ash as promising sources of REEs. This is particularly significant considering the high global demands for REEs. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND The contents of many heavy metals in soil in many areas of southwest China are much higher than the national soil background value, and related studies show that most heavy metals in soil are in a state of “high background and low activity”, which is closely related to the special geological process in the area. Most scholars have concentrated more on the weathering process and post-weathering heavy metals of granite, basalt, carbonate rocks and other geological bodies with high background value of heavy metals in southwest China. However, alkali-enriched porphyry also has the characteristics of high background value of heavy metals, and the geochemical behavior characteristics of heavy metals in the weathering process of alkali-enriched porphyry are less studied. The ecological and environmental effects of heavy metal element migration and transformation during weathering are still unclear. There is a large-scale alkali-enriched porphyry belt located in southwest China. Most of the alkali-enriched porphyry areas have precious metals such as gold and silver, and polymetallic deposits such as copper, lead and zinc. Therefore, soil in alkali-enriched porphyry areas usually has the characteristic of high background value of heavy metals. OBJECTIVES For identifying geochemical characteristics of heavy metal elements and a series of ecological and environmental problems during the soil-forming process of alkali-enriched porphyry, to provide a scientific basis for the prevention and control of heavy metal pollution in alkali-enriched porphyry areas and rational planning of agricultural planting. METHODS For sufficient hydrothermal conditions and strong soil-forming in Yunnan Province, a rock weathering profile of Yao’an alkali-enriched porphyry in central Yunnan Province was selected as the research object. The contents of As, Cd, Cr, Cu, Hg, Ni, Pb, Zn, Al2O3, TFe2O3, CaO, Na2O, K2O, MgO, SiO2, organic carbon and pH in rock/soil samples were determined by inductively coupled plasma-mass spectrometry/optimal emission spectrometry (ICP-MS/OES), atomic fluorescence spectrometry (AFS), X-ray fluorescence spectrometry (XRF) and volumetric method. Multivariate statistics method and mass migration coefficient were used to study the distribution characteristics, migration and enrichment rules of heavy metal elements in the weathering profile, as well as the factors affecting the migration and enrichment of heavy metals. RESULTS Based on the analysis of the content and distribution characteristics of eight heavy metals in the weathering profile of Yao’an alkali-enriched porphyry, the migration and enrichment mechanism of heavy metals during the weathering process was identified, and the environmental risk assessment of the surface soil in the area was carried out. (1) In the weathering profile, all the weathering strata have the same source as the bedrock material, and there is no exogenous addition. Different degrees of desiliconization and aluminum-iron enrichment occur in the whole weathering process, especially in the surface layer. In the bottom-up evolution process, all of the heavy metal elements except Cd show an overall trend of increasing content. As, Cr, Cu, Hg and Ni are enriched to different degrees during weathering, while Cd, Pb and Zn are leaching out. The order of heavy metal migration capacity from strong to weak is Cd>Zn>Pb>Hg>Cu>As>Ni>Cr. As, Cr, Cu, and Hg have similar geochemical behavior, as do Cd, Pb, and Zn. (2) Cd, Pb and Zn occur mainly in feldspar minerals and lead-zinc metallic minerals and exhibit the characteristics of migration and leaching under acidic and strong leaching conditions. Although the bedrock is obviously deficient in Cu, Cr, Ni and Hg, it is eventually enrichedin-situ in clay minerals and Al and Fe oxides/hydroxides with weathering due to its own chemical properties and the effect of desilication to enrich aluminum and iron. The enrichment of As is mainly controlled by aluminum-Fe enrichment, and the strong aluminum-Fe enrichment in the study area results in the in-situ secondary enrichment of As. (3) The soil ecological environment in the study area may be polluted by As and Pb due to the high content of Pb in the bedrock and the effect of aluminum-iron enrichment. CONCLUSIONS The risk of As and Pb pollution may exist in the soil ecological environment of the study area, and a large amount of Pb leaching may migrate into the Dragonling River with surface runoff. It is necessary to strengthen the monitoring of heavy metals such as As and Pb in the overlying soil of alkali-enriched porphyry and heavy metals such as Pb and Zn in the rivers around alkali-enriched porphyry so as to ensure ecological safety.

BACKGROUND The emerald is loved by people because of its gorgeous color and is respected as one of the world's four major gems. Due to the high value of emeralds, a variety of synthesis and optimization methods have emerged. The hydrothermal method is one of the common methods to produce synthetic emeralds. The emeralds synthesized by this method have typical water ripple texture, showing a serrated parallel arrangement, and the characteristic peaks of the infrared absorption spectrum in the range of 2300-3100cm-1 are the main identification feature. However, some emeralds synthesized by this method do not have the above typical characteristics. This has brought a great challenge to the quality inspection agencies, and brought many doubts to the majority of consumers, and affected the stability of the gem market. OBJECTIVES It is essential to study the new emerald synthesized by this new hydrothermal method. The refractive index, density, polychromatism, and infrared absorption spectrum characteristics of the tested samples are very similar to those of natural emeralds, so infrared absorption spectrum analysis cannot obtain the supporting evidence of its cause. Based on this, the gemological and spectral characteristics of the test samples were studied by ultraviolet visible spectrum, energy dispersive X-ray fluorescence spectrometry (EDXRF) and other spectroscopic means. Finally, the test samples were determined to be a new kind of emerald synthesized by the hydrothermal method. METHODS The refractive index, birefringence, relative density, polychromaticity and weight of the samples were tested by refractometer, electronic balance, and dichroic mirror. The internal and external characteristics of the test samples, the cutting and polishing quality of the samples, and the characteristics of internal inclusions were observed by gem microscope. The infrared reflection spectrum and infrared transmission spectrum characteristics of the samples were analyzed by Fourier transform infrared spectrometer and compared with the infrared spectrum characteristics of emeralds from different origins. The absorption spectrum characteristics of the samples were analyzed by ultraviolet-visible spectrometer, focusing on the absorption peak characteristics near 830nm. The element characteristics of the samples were tested by EDXRF, because the content characteristics of Cr and Ni in emerald are the key to identify whether it is natural or not. RESULTS The mass of the tested samples was 0.17-0.56g, the refractive index was 1.571-1.588, the birefringence was 0.007-0.009, the relative density was 2.56-2.78, and the polychromaticity was obviously blue-green/green. These conventional gemological characteristics were consistent with natural emeralds. The samples were observed under a gemstone microscope, and the samples had a parallel texture of suspected water ripple, but not typical. The water ripple texture of the typical hydrothermal synthetic emeralds was serrated parallel arrangement. However, the characteristics under the gem microscope should arouse the suspicion of jewelry inspectors.The infrared reflectance spectra of the samples had characteristic peaks of 1242, 1219, 1022, 968, 810, 741, 687, 594, 528, 490, and 459cm-1. The characteristic peaks of 1242, 1219, 1022, 968, 810, 741, and 687cm-1 were caused by the stretching vibration of Si—O—Si and O—Si—O, and the characteristic peaks of 594, 528, 490, and 459cm-1 were caused by the bending vibration of Si—O and the vibration of M—O. The infrared reflection spectrum characteristics of the samples were consistent with the infrared spectrum characteristics of beryl, but the infrared spectrum characteristics of the fingerprint area could not indicate whether the samples were natural or synthetic.The infrared transmission spectra of the samples had 5445, 5273, 5109, 4874, 4800, 4650, 4547, 3321, 3222, 3027, 2953, 2928, and 2431cm-1 characteristic peaks. 5273cm-1 was caused by typeⅡ water absorption, 5445cm-1 and 5109cm-1 were caused by typeⅠ water absorption. The typeⅡ water absorption peak of the test samples was relatively sharp at 5273cm-1, and the typeⅠ water absorption peaks at 5445cm-1 and 5109cm-1 were relatively strong. Compared with previous studies, the shape and intensity of water absorption peaks of natural emerald and hydrothermally synthesized emerald were different. The infrared absorption spectrum characteristics of the water of the test sample were different from those of natural emerald, but the diagnostic direct evidence could not be obtained from the infrared absorption spectrum. The infrared peak in the range of 2300-3100cm-1 is caused by Cl- ion absorption. According to the results of previous studies, the absorption intensity of hydrothermal synthetic emeralds in this wavenumber range was significantly stronger than that of natural emeralds. The infrared absorption spectra of the test samples were relatively weak in the range of 2300-3100cm-1, which was more similar to the infrared absorption spectrum characteristics of natural emeralds in Colombia, Yunnan, Madagascar and Brazil, and was obviously different from the infrared absorption spectrum results of emeralds synthesized by the hydrothermal method. There were obvious differences between the infrared transmission absorption spectra of the traditional hydrothermal synthetic emeralds and natural emeralds. The characteristics of infrared absorption spectra are important evidence for identifying the genesis of emeralds. However, it is difficult to obtain the final accurate conclusion from the infrared absorption spectrum analysis of the test samples described in this paper, so they have been named 'new' type.The UV-Visible spectrum characteristics of the test samples showed that the absorption peak below 350nm was caused by the Fe2+-O2- charge transfer band in emerald, the absorption peak at 429nm was caused by Cr3+ ions, the broad absorption band at 550-650nm was mainly caused by Cr3+ ions, the absorption peak at 683nm was caused by Cr3+ ions, the sharp absorption peak at 956nm was caused by water absorption, and the broad absorption peak near 850nm should be caused by Fe2+ absorption, which was rarely seen in the previous hydrothermal synthesis of emerald. The combination of Cr3+ and Fe3+ replacing Al3+ makes emerald, green. The absorption peak of UV-Visible spectrum caused by Fe2+ in natural emerald was in the range of 810-850nm, and only a few of the absorption bands caused by Fe2+ in natural emeralds are not obvious. The absorption band of the UV-Visible spectra of the test samples was not obvious or weak in the range of 810-850nm, and the 850nm absorption peak of individual samples was obvious. Therefore, the emeralds examined by ultraviolet-visible spectroscopy may be synthetic, but this could not be conclusively confirmed.The EDXRF results showed that the samples had Fe, Ni and Cr elements, which was different from previous studies of natural emeralds. Yang Zhuo(2010) studies showed that the main trace elements in natural emeralds, from different origins such as Brazil, Colombia, Egypt, India, South Africa, Zimbabwe and Canada by LA-ICP-MS, were Fe, V, Cr, Mg, Na and Cs, but the content of Ni was very low, far lower than that of Cr. The content of Cr in Yunnan emeralds was 58-177μg/g, and Ni was not detected (Bai et al., 2019). The chemical element characteristics of gem-grade emeralds in Afghanistan, Brazil, Colombia, Ethiopia, Madagascar, Russia, Zambia and Zimbabwe showed that Ni element was not detected (Karampelas et al., 2019). The elemental composition of emeralds from South Africa, Afghanistan, Australia, Colombia, Egypt, Madagascar, Zambia, Zimbabwe, Tanzania and China was analyzed by electron probe microanalysis, and Ni was not detected (Lum et al., 2016). It could be seen that Cr and Fe elements coexisted in natural emeralds, but Ni was almost non-existent. EDXRF was used in this study without quantitative analysis but calibrated by the gold standard sample, and the relative peak intensity of the element was of great significance. The peak intensity of the Ni element in the test sample was much higher than that of the Cr element, which did not conform to the element content characteristics of the natural emerald, and was consistent with the high content of Ni in the hydrothermal synthesis of emerald reported by Lu and Shen (2021) and Yang et al.(2022). The comprehensive analysis showed that the test sample was a synthetic emerald. CONCLUSIONS The infrared absorption spectrum characteristics of the test samples are similar to those of natural emeralds, and the infrared absorption spectrum could not be used as a basis for identifying the genesis of emeralds. Previous studies show that a set of absorption peaks in the range of 2300-3100cm-1 in the infrared absorption spectrum is an important identification feature of the hydrothermal synthesis of emeralds, but this feature is not obvious in the tested samples. The UV-Visible spectrum of the sample shows that the absorption band near 810-850nm related to Fe2+ is not obvious. The X-ray fluorescence spectra of the samples show that the Kα peak intensity of Ni is much higher than that Kα of Cr, which is the main feature of the new emerald synthesized by the hydrothermal method. It could be seen from the experimental results that the identification of jewelry and jade is a systematic work. It is necessary to learn from the previous results and combine the comprehensive analysis of various detection methods to obtain the correct result.

The main fluorine-concentrating minerals in rocks are mainly apatites, amphiboles, micas, fluorites, sphenes, villiomites, in which fluorine is found in compounds with Ca, Mg, Na. The yield of the X‑ray fluorescence of fluorine depends on the element with which it is chemically bound. Taking into account this factor, three versions of calibration dependences for fluorine in the composition of CaF2, MgF2, and NaF were obtained using pressed tablets. Mixtures of these fluorides with granite, basalt, and limestone were used for calibration. To select an adequate calibration for the determination of fluorine in a batch of unknown samples, it was proposed to use the results of a selective analysis of fused samples of the batch. [ABSTRACT FROM AUTHOR]

In this study, four analytical techniques for the detection of Sc, La, Ce, Nd, Sm, Eu, Tb and Lu in volcanic rock specimens from Ghana have been compared. These rock samples were examined using inductively coupled plasma mass spectrometry, X-ray fluorescence spectrometry, and instrumental neutron activation analysis. The Am-241 excitation-based X-ray fluorescence accuracies were good for Y, La, Ce, Nd, Eu, and the results were comparable to inductively coupled plasma mass spectrometry and instrumental neutron activation analysis except Silver-anode X-ray tube X-ray fluorescence. This demonstrates the limitations of the tube-based X-ray fluorescence excitation system for rare earth elements analysis, primarily caused by interference between the K-series X-ray emission from the transition metals and the relatively low intensities of L-series lines of the rare earth elements. Data on the precision and accuracy of these methods were based on IAEA SOIL-7 reference material. [ABSTRACT FROM AUTHOR]

BACKGROUND The quality of soil is directly related to human health and the safety of agricultural products, which has important references for agricultural planting and land planning. As an important vegetable basket base in Chengdu, Tangchang Town has developed agricultural planting, but the recent soil quality in the region is still unclear. OBJECTIVES In order to accurately understand the current content of nutrient and heavy metal elemental characteristics and soil quality grade of topsoil in the Tangchang agricultural planting area. METHODS According to 1∶50000 soil quality geochemical survey, 810 topsoil samples were collected. The contents of N, P, K, As, Cd, Hg, Pb, Cr, Ni, Cu, Zn, Se and pH in these soil samples were determined by X-ray fluorescence spectrometry, inductively coupled plasma-mass spectrometry, atomic fluorescence spectrometry, element analyzer and ion selective electrode method. The element geochemical characteristics and soil nutrient grade, soil environmental quality grade and comprehensive soil geochemical grade were then evaluated. RESULTS (1) Compared with the general topsoil in China, Zn and Pb in the topsoil of the study area are slightly enriched, Se is relatively enriched, N, P, Cd and Hg are strongly enriched. The topsoil is generally weakly acidic. (2) The comprehensive grade of soil nutrients is rich in second grade, accounting for 88.0% of the area, and the soil fertility is rich. The proportion of the first grade soil area in the environmental quality grade of the eight heavy metal elements in the soil is more than 96.0%, and the comprehensive environmental quality grade is dominated by first grade clean type, accounting for 98.06%. The comprehensive quality of soil is mainly grade one, accounting for 85.85%. (3) The area of selenium-rich soil in the region is 2.49km2, accounting for 3.7%, sporadically distributed in the central study area. Copper-rich soil area is 63.13km2, accounting for 94.0%, and zinc-rich soil area is 63.31km2, accounting for 94.17%. CONCLUSIONS In summary, the nutrients of topsoil in Tangchang Town are rich, the soil environment is clean and the comprehensive quality of the soil is high.

Copyright of Rock & Mineral Analysis is the property of Editorial Board of Rock & Mineral Analysis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The determination of mineral concentrations in rice grain samples is crucial for analyzing their nutritional content. Most mineral content analysis techniques depend on inductively coupled plasma (ICP) spectrometry and are often complicated, expensive, time-consuming, and laborious. Recently, the handheld X-ray fluorescence (XRF) spectrometer has been randomly used in earth sciences; however, it is hardly practiced in quantifying mineral content in rice samples. In this research, the reliability of XRF results was compared with that of the ICP-OES to determine zinc (Zn) concentration in rice (Oryza sativa L.). Approximately 200 dehusked rice samples and four known high-Zn samples were analyzed using both XRF and ICP-OES techniques. The concentrations of Zn were recorded using the XRF technique and then correlated with the ICP-OES results. The results indicated a high positive relationship between two methods, with R2 = 0.83, p = 0.000, and the Pearson correlation value of 0.91 at the level of 0.05. This work demonstrates the potential of XRF as a reliable and low-cost as well as an alternative technique to ICP-OES methods for determining Zn content in rice as it allows the analysis of a greater number of samples in a short period at a considerably low price. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND The Hetian nephrite belt in Xinjiang is the largest nephrite ore belt in the world, with a length of about 1300km. In addition to white, gray, black and brown nephrite, the Qiemo—Ruoqiang zone, Xinjiang also produces a yellow-green nephrite. There are few studies on the color origin and characterization of this kind of Hetian nephrite, which affects the understanding of the color and genesis of this kind of Hetian nephrite. OBJECTIVES To understand the color genesis, genetic types and formation age of the yellow-green nephrite in Qiemo—Ruoqiang deposit. METHODS Electron probe microanalysis (EPMA), backscattered electron (BSE) image, X-ray fluorescencespectrometry (XRF), and high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS) were used to investigate mineral and chemical composition. The FeO content was determined by titration method to explore its color origin and genetic type, and the zircon U-Pb isotope dating by sensitive high-resolution ion microprobe (SHRIMP) was used to constrain its mineralization age. RESULTS Yellow-green nephrite in Qiemo—Ruoqiang was predominately composed of apatite, calcite, dolomite, diopside, epidote, sphene and zircon. The yellow-green nephrite whole rock had low total REE (∑REE=2.61-19.1μg/g) with obvious Eu negative anomaly (δEu < 0.05), LREE right dipping, and HREE flat pattern. According to the distribution pattern of rare earth and the content of Cr and Ni, it was inferred that it was a magnesia skarn type Hetian nephrite. Compared with other nephrite in the world, the average value of Fe3+/Fe2+ of the yellow-green nephrite in Qiemo—Ruoqiang (average=0.16) overlapped with nephrite in other regions. The ratio is slightly higher (0.07-0.26), while the content of Fe3+ and Fe2+ was not significantly different between the yellow-green nephrite and other color nephrite. The SHRIMP U-Pb dating of zircon in the yellow-green nephrite yielded ages of 461.7±6.1Ma (MSWD=1.6) and 498.1±4.6Ma (MSWD=1.16). CONCLUSIONS The color genesis of the yellow-green nephrite in Qiemo is probably related to the ratio of Fe3+/Fe2+, but not to the content of Fe3+ and Fe2+. The SHRIMP U-Pb dating results of zircon in yellow-green nephrite represent the formation age of the yellow-green nephrite. These new data provide geochronological constraints for the magmatism of Hetian nephrite belt and the tectonic evolution of the West Kunlun orogenic belt.

Novel X-ray fluorescence technique is applied for determination of ferrous iron (FeO) content for reference material characterization in addition (or as alternative) to volumetric method. Approach is based on the dependence of FeKβ 5 line relative intensity on the iron valence state. A set of 99 reference materials was studied to choose optimal calibration set containing rocks of different composition: ultrabasic, basic, intermediate, and acid igneous rocks, silicate sedimentary and metamorphic rocks. The ratio of FeKβ 5 and FeKβ 1,3 lines intensities was chosen as analytical parameter. A set of 40 GeoPT samples was analyzed, and it was shown that the uncertainty of proposed X-ray fluorescence technique is comparable to one of certified volumetric (potassium dichromate titration) technique for the samples with Fe 2 O 3 tot content more than 1 wt%. The presence of Sr and Co in usual for rocks content (up to ∼0.23 wt% and ∼200 μg/g respectively) does not affect to the measurement uncertainty. Analytical potential, limitations and features of proposed technique are discussed. [Display omitted] • Novel XRF approach is proposed for reference materials characterization. • FeO content was determined in 40 GeoPT samples. • The uncertainty was compared with certified volumetric technique. • The use of XRF method increase the reliably of analytical results. [ABSTRACT FROM AUTHOR]

BACKGROUND Selenium (Se) is one of the essential trace elements for humans, and an important way for humans to obtain and supplement selenium is by eating natural selenium-enriched agricultural products. The geochemical characteristics of selenium in the survey area are an important basis for the effective utilization of selenium-enriched land resources and the development of selenium-enriched agricultural and sideline products. OBJECTIVES To investigate the geochemical characteristics of selenium content, distribution and influence factors in the study area. METHODS Soil and crop samples were collected from a central village of Zhaojue County, Sichuan Province. AFS, XRF and ICP-MS were used to determine the contents of elements including Se, Al2O3, TFe2O3, SiO2, OrgC, and pH values. Geochemical characteristics of selenium content, distribution and influencing factors in the study area were investigated using statistical and correlation analysis. RESULTS (1) The soil selenium content in the study area ranged from 0.04 to 1.50mg/kg, with an average value of 0.33mg/kg. The delineated selenium-enriched soil area was 7.23km2, accounting for 30.31% of the total soil area. The selenium content of the soil developed in basalt was the highest, with an average of 0.4mg/kg, indicating that the geological background in the area was closely related to the soil selenium content. The Se-enriched soil in the area was mainly controlled by the Emeishan basalt Formation, which contained basalt intercalating with picrite and tuffaceous sand and mudstone. (2) The enrichment capacity of selenium varied in different land utilization and soil types. The absorption capacity of selenium in soil decreased due to human agricultural activities. Clayey particles or iron oxides in the yellow-brown loam layer were easy to combine and enrich selenium. The selenium content in acidic soil was inversely correlated to pH value. There was a significant positive correlation between soil organic matter and selenium content. Soil texture had a certain effect on selenium content. (3) Corn and potatoes from selenium-enriched soils had very low selenium content. CONCLUSIONS During the exploitation and utilization of selenium-enriched soil, organic fertilizer should be added in time and soil pH should be adjusted in agricultural areas such as dry land and paddy field, and other agricultural products should be developed by using selenium-enriched resources.

BACKGROUND Blue amber is mainly produced in the Dominican Republic, Mexico and Myanmar. Generally speaking, the formation mechanism, composition and spectral characteristics of blue amber are closely related to its specific geographical environment. Therefore, the study on the origin of blue amber has become a hot topic in the field of gemology, archaeology and biological mineralogy, and the origin of geographical districts of blue amber has become a hot research topic. Previous studies mainly used infrared spectroscopy, X-ray fluorescence spectroscopy, mass spectrometry, and isotope tracing to carry out a relatively systematic study on the origin of blue amber, but were limited to the similarity of blue amber, and the spectral characteristics of blue amber from different origins showing similarities. Due to the low popularity of the application of some detection devices, the application of the detection method based on the above-mentioned corresponding devices is greatly limited. OBJECTIVES To identify photoluminescence (PL), Raman spectroscopy and trace element characteristics of blue amber with different origins. METHODS Photoluminescence and Raman spectroscopy combined with trace element analysis were used to study the spectral and elemental occurrence characteristics of blue amber from Dominican Republic and Mexico. RESULTS The results showed that: (1)At room temperature, using PL spectrum with 405nm as the excitation wavelength, the peaks at 450, 475 and 502nm appeared simultaneously for blue amber from Dominican Republic. In contrast, there was no significant characteristic peak in Mexican blue amber. The differences in PL spectrum of blue amber from the two origins can be used as a direct basis for the traceability and identification of its origin. (2)Using the Raman spectrum with 785nm as the excitation wavelength, the Raman peaks of blue amber from Dominican Republic at about 154, 468, 901, 1177 and 1312cm-1 were more prominent or sharper than those from Mexico. The ratio of the peak intensity at 1653 and 1446cm-1 (N=I1653/I1446) in the corresponding spectrum of the amber from Dominican Republic was significantly higher than that from Mexico. (3)Trace elements of S, Si, Fe and Cu were present in the blue amber from the two regions, and the content was S>Si>Fe>Cu. The content of Cu in blue amber from Dominican Republic was generally higher than that from Mexico. Therefore, the occurrence and content characteristics of Cu can be used as one of the evidences for the traceability of Dominican blue amber. CONCLUSIONS The research work provides theoretical and technical support for the origin of blue amber with different geographical locations. It can also provide a salutary reference for identification of the geographical location for other gems.

The aim of this study was to determine whether X-ray fluorescence spectrometry (XRF) could be used to detect changes in hair zinc concentration in response to a modest daily increase in zinc from the consumption of zinc biofortified wheat flour. This study was conducted as part of an effectiveness trial (BiZiFED2) exploring the potential for zinc biofortified wheat to alleviate zinc deficiency in adolescent girls aged 10–16 years in Pakistan (trial registration ID ISRCTN17107812). A randomized controlled design was used. Participants received either control flour or zinc biofortified flour for 6 months. Consumption of biofortified flour resulted in an average daily increase in dietary zinc intake of 1.5 mg per day above that of the control flour. At baseline and at the end of the intervention, individual hair samples (control: n = 59, intervention: n = 64) were analyzed for zinc and sulfur content by XRF. Data were analyzed using linear mixed effects models to contrast between trial groups the changes from baseline to end point and also to compare baseline and end point values within each trial group. Increases from baseline to endpoint in both sulfur and zinc were significantly greater in the intervention group compared to control (sulfur counts. Control: baseline = 119.87 ± 20.33 and endpoint = 121.58 ± 23.58/intervention: baseline = 122.67 ± 24.19 and endpoint = 131.60 ± 21.34); (Zinc counts. Control: baseline = 50.88 ± 14.33 and endpoint = 54.82 ± 14.61/intervention: baseline = 49.61 ± 10.77 and endpoint = 58.79 ± 12.20). For these parameters, there were also significant increases from baseline to endpoint in the intervention group but not in control. Furthermore, for Zn:S count ratio there were no differences in terms of the magnitude of the change from baseline to endpoint in the control group, although significant increases from baseline to endpoint were evident in the intervention group (Zn:S count ratio. Control: baseline = 0.42 ± 0.10 and endpoint = 0.45 ± 0.08/intervention: baseline = 0.41 ± 0.08 and endpoint = 0.45 ± 0.08). A modest increase in dietary zinc over 6 months resulted in a detectable increase in both sulfur and zinc counts in individual hairs measured using XRF. This offers a sensitive, non-invasive method to monitor changes within subjects in response to dietary zinc interventions.