Application of energy dispersive X-ray fluorescence spectrometry as multielemental analysis to determine the elemental composition of crumb rubber samples

The elemental content of different rubber samples was analyzed using different analytical methods (inductively coupled atomic emission spectroscopy and non-polarized energy dispersive X-ray fluorescent spectroscopy). A new application of energy dispersive X-ray spectrometry as an analytical method for the determination of elemental content of rubber samples was investigated. Control analyses were also carried out to compare the results by ICP-AES. In one hand four samples contained same quality of elements (Mg, Si, P, S, Ca, Fe, Zn), while another four samples were without phosphorous. On the other hand there were significant differences in the ratio of C/H in the case of each sample. Based on the results, it was concluded that the X-ray spectrometry as an analytical method is well-applicable to determine the elemental composition of rubber samples, but the calibration is a key part of the analysis. A good correlation was observed between the different methods, but the correlation was the function of characteristic of matrices. Significant matrix effect from the presence of phosphor was observed in the case of some samples, while the change of C/H ratio could not result notable matrix effect.     

Heavy metals and some other elements in medicinal plants. Determined by X-ray fluorescence analysis

Determination of Mn, Fe, Cu, Zn, Hg, Pb, Br, Se, Rb, Sr and Cd in the medicinal plants by radionuclide X-ray fluorescence analysis (using²³⁸Pu,²⁴¹Am/Ag and¹²⁵I) is described.     

Analysis of trace elements in medicinal plants with energy dispersive X-ray fluorescence

Mankind still depend on traditional herbal medicine for the treatment of various diseases and ailments. This paper discusses the elemental composition and concentration of medicinal plants investigated by energy dispersive X-ray fluorescence. The elements present in medicinal plants are P, Cl, K, Ca, S, Al, Ti, V, Rb, Sr, Zr, Nb, Mo, In, Sn, I and Ce. The physical basis of the used analytical method, the experimental set up and the procedure of sample preparation are presented. This revised version was published online in August 2006 with corrections to the Cover Date.     

Application of X-ray spectroscopy in nondestructive photon activation analysis

A survey is given on the use of X-ray spectroscopy for the qualitative and quantitative analysis of samples activated by 30 MeV bremsstrahlung from an electron linear accelerator. Detection limits are calculated from the measured X-ray spectra and compared with those for γ-ray spectroscopy. The advantages and limitations of the method are discussed. Some practical applications of X-ray spectroscopy in nondestructive multielement analysis are quoted.     

Trace element analysis via heavy ion induced X-ray fluorescence

Ohne ZusammenfassungWork supported by the National Science Foundation, Grant MPS 75-17746.     

Determination of trace elements in Syrian medicinal plants and their infusions by energy dispersive X-ray fluorescence and total reflection X-ray fluorescence spectrometry

X-ray fluorescence (XRF) and total-reflection X-ray fluorescence (TXRF) techniques suited well for a multi-element determination of K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr in some Syrian medicinal plant species. The accuracy and the precision of both techniques were verified by analyzing the Standard Reference Materials (SRM) peach-1547 and apple leaves-1515. A good agreement between the measured concentrations of the previously mentioned elements and the certified values were obtained with errors less than 10.7% for TXRF and 15.8% for XRF. The determination of Br was acceptable only by XRF with an error less than 24%. Furthermore, the XRF method showed a very good applicability for the determination of K, Ca, Mn, Fe, Cu, Zn, Rb, Sr, and Br in infusions of different Syrian medicinal plant species, namely anise (Anisum vulgare), licorice root (Glycyrrhiza glabra), and white wormwood (Artemisia herba-alba).     

Multielement determination of the composition of sulfide ores using X-ray fluorescence analysis

The potentials of the multielement X-ray fluorescence analysis of sulfide ores from one sample are studied. Using cluster analysis, sulfide ores are divided into four groups; within each group, the ores are similar in chemical composition and matrix effects. Calibration equations are obtained for each group. The performance characteristics of the determination results are evaluated.     

Trace element content of medicinal plants from Algeria

Neutron activation analysis (INAA) has been applied to multielemental determination of eleven medicinal plants used to cure the urinary tract diseases observed in Algeria. These plants include Androgena Citratus, Ceratonia Siliquata, Punica Granatum, Glyryrrhiza Glabra, Lausaunia Alba, Fragaria Vesca, Arbutus Unedol, Hordeum Vulgaris, Papieteria Officinalis, Zea Mays L, and Davallia Seae. Concentrations of twenty elements Ba, Br, Ca, Cl, Co, Cu, Cr, Fe, I, Mn, Na, Mg, Rb, Sb, Se, Sc, Sr, Ti, V, and Zn have been determined by short, and long irradiation times with a thermal and epithermal flux of 1.4·10¹² n·cm⁻²·s⁻¹ and 1.4·10¹¹ n·cm⁻²·s⁻¹, respectively. These analyses were performed in conjunction with Compton suppression. In almost herbs studied the Co, Cr, Cu, Rb, Sb, Sc, Se and V are found to be present at trace levels, Br, Mn, and Zn at the minor level, and Ca, Cl, Fe, Mg and Na are generally at the major level. The accuracy of the measurements has been evaluated by analyzing NIST-botanical references materials.     

Application of total-reflection X-ray fluorescence spectrometry in material analysis

X-ray fluorescence spectrometry with total reflection conditions is applied in the qualitative and quantitative determination of impurities in thin layers of Ti, TiO₂, and HfO₂ prepared by evaporation and of SiO₂, TiO₂, and Ta₂O₅ prepared by ion beam sputtering. The same method is used to examine stainless steel discs, which have to be used as reference materials,Dedicated to Professor Günther Tölg on the occasion of his 60th birthday     

Sound-producing sand in Japan: major element composition and its minerals determined by X-ray diffraction and X-ray fluorescence.

The major element composition, including two kinds of clay minerals and moisture content of sound-producing sand are reported for the first time. Sand from 33 beaches in Japan has been found to make sound. Ten sound-producing beaches were selected to compare with silent beach sand. Both sound-producing sand and silent beach sand are mostly composed of quartz and feldspar. The range of SiO2 content of sound-producing sand is not different from silent sand samples. This indicates that a high quartz content is not necessary to produce sound, although more than 60 weight percent of quartz is necessary. One silent sand recovered its sound after a 3.5 percent HNO3 treatment. Also, a small portion of clay minerals was found. A clean grain surface is a necessary factor for sand to produce sound. Illite was found in all silent sand samples.     

Total reflection X-ray fluorescence analysis of fly ash from Bulgarian coal-fired power plants

The contents of Cl, Ca, K, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Rb, Sr, Ba and Pb in raw coal fly ash from five Bulgarian power plants were determined by total reflection X-ray fluorescence (TXRF), using gallium as the internal standard. The samples were analysed as in slurry form in Triton? X-114. The experimental parameters, such as grain size, concentrations of fly ash slurry and excitation time were optimised. For validation of the method, the certified reference material BCR-176R fly ash was used. The precision of the results obtained is characterised by a relative standard deviation of approximately 10%. The resulting data confirm the suitability of TXRF for the simultaneous determination of major, minor and trace elements in coal fly ash samples. Further advantages provided by TXRF are easy sample preparation (no sample dissolution) and the small sample amount required for analysis.     

Applications of total reflection X-ray fluorescence spectrometry in trace element and surface analysis

Total reflection X-ray fluorescence spectrometry (TXRF) is presented as a genuine surface analytical technique. Its low information depth is shown to be the characteristic feature differentiating it from other energy dispersive X-ray fluorescence methods used for layer and surface analysis. The surface sensitivity of TXRF and its analytical capability together with the limitations of the technique are discussed here using typical applications including the contamination control of silicon wafers, thin layer analysis and trace element determination. For buried interfaces and implantation depth profiles in silicon a combination of TXRF and other techniques has been applied successfully. The TXRF method has the particular advantage of being calibrated without the need for standards. This feature is demonstrated for the example of the element arsenic.     

Determination of Fe and Zn in healing plants by radionuclide X-ray fluorescence analysis

Radionuclide X-ray fluorescence method was used for the determination of Fe and Zn in healing plants (Sage, Peppermint, Stinging, Common Agrimony, Milfoil, Ribwort, Tansy, White Dead-Nettle).²³⁸Pu exciting source and Si/Li semiconductor detector were used for the determination.     

X-ray photoelectron spectroscopy for nondestructive analysis of buried interfaces

The possibility to use high energy X-ray photoelectron spectroscopy as a nondestructive method of in-depth chemical phase analysis of solids is demonstrated. Theoretical background and optimal experimental conditions of in-depth analysis are considered. Interfaces in 5 nm thick HfO₂ films synthesized by molecular layering and deposition of organometallic compounds from the gas phase were studied. It was shown that thickness of the layers in multilayer structures can be determined by measuring the intensity of photoelectron peaks.     

X-ray fluorescence spectrometry applied to the analysis of environmental samples

X-ray fluorescence spectrometry is an expanding technique in the field of environmental analysis for both air and water pollution studies. Its capabilities now include the determination of gaseous contaminants in air in addition to the established area of elemental analysis, covering airborn particulates and soluble trace elements in water.     

X-ray fluorescence analysis of rocks

Summary Modern methods for the determination of various elements in geological materials by XRFA are reviewed. XRFA theory and metrological characteristics are discussed in detail.

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Röntgenfluorescenzanalyse von Gesteinen

     

Essential and trace element contents of some Nigerian medicinal plants

The energy-dispersive X-ray fluorescence (EDXRF) spectroscopy has been used for the determination of essential and trace elements" contents of some twenty Nigerian medicinal plants. The accuracy and precision of the technique were assured by analyzing the European Community Bureau Reference Standard BCR 62 (Olive Leaves). Fourteen elements, namely K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr were detected with toxic heavy metal such as Cd, As, Pb, Hg were detected in the samples. The ranges of elemental concentrations varied from 7.7^.10⁴ to 1.6 mg/kg in the herbs. The results show that many of these plants contain elements of vital importance for human metabolism and prevention and healing of diseases.     

Radioisotope X-ray fluorescence analysis of some elements in fly ash of Afsin-Elbistan power plants

Energy dispersive X-ray fluorescence technique was used for the determination of As, Sr, Mo, Ba, In and Ce in fly ash Afsin-Elbistan power plants using the standard addition method. An annular²⁴¹Am source was employed for excitation of the K shell of the elements.     

X射线荧光光谱分析

作为《分析试验室》定期评述“X射线荧光光谱分析”系列评论第八篇,本文收集国内学者在1998年7月至2000年6月期间公开发表在国内外期刊和国际会议文集上的129篇论文,并对此期间对我国X射线荧光光谱分析的概况、发展和国际上的地位进行了讲述,内容包括仪器及维修、基体校正、数据处理方法、谱分析方法的研究、标样及样品制备、全反射X射线荧光光谱、同步辐射光源X射线荧光光谱、粒子激发X射线发射、X射线荧光光谱分析方法研究及其应用。     

Specific features of matrix correction in the X-ray fluorescence analysis of samples of widely varied composition

The authors critically analyze the paper “Corrections for matrix effects in X-ray fluorescence analysis” [1], which was declared by R. Rousseau as a tutorial but contains some inaccuracies. Conclusions are confirmed by the results of experiments and theoretical calculations. It is shown that uniform linear calibration function I _i /I _i ^m = f(R _i ^th ) can hardly be obtained for test samples of any composition because of the difference in their microstructure and the variation of the background. At the same time, in the XRF analysis of multicomponent materials, such as steels, the Lucas-Tooth and Jongh equations provide a good alternative to the Rousseau algorithm.