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1.
The aim of the present work is to demonstrate the application of the x‐ray fluorescence (XRF) technique to the determination of Rb, Sr, Y, Zr, and Nb contents in phosphorites. The effect of a chemical sample composition on fluorescence intensities of analytical lines has been taken into account using the background standard method. A novelty of the work is the detailed study of a background to choose the background position, free from the spectral line overlaps of the elements presented in the sample. The most suitable background position is the position at the angle 2θ = 29° when using the analyzing crystal LiF(200). During our investigation we faced a problem of choice of Certified Reference Materials (CRMs) for the calibration of the phosphorites. To estimate interelement effects and to choose CRMs for the calibration the intensities were theoretically calculated. The statistical processing of analytical results of the technique is carried out. This technique may be applied to the determination of Rb, Sr, Y, Zr, and Nb contents in the phosphorites. Also, the possibility has been demonstrated to use the XRF technique for geochemical investigations of rocks. Phosphorites of Bokson‐Khubsugul Basin were selected as an example. As a result of the investigation the genetic type of phosphorites was established, which corresponded to the present geodynamical depositional environment. The character of the distribution of Rb, Sr, Y, Zr, and Nb contents in the phosphorites was also studied. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

2.
Archaeological finds of Neolithic to Iron Age pottery show clay potsherds characterized by red cord‐markings. The items date back from 5500 to 1500 B.P. To better understand temporal changes in the provenance of raw‐material sources, and the nature of materials used in the red colorant and ceramic bodies, micro‐Raman spectroscopy, X‐ray diffraction analysis (XRD), and micro X‐ray florescence spectroscopy (μXRF) were applied to 29 red‐coated potsherd samples found at twelve archaeological sites across Taiwan. The techniques identified the chemical and mineralogical composition of the red coatings and ceramic bodies as well as the production methods of ancient potters. Eighteen mineral phases were identified from the Raman spectra, including hematite, α‐quartz, and anatase. Feldspar, rutile, pyroxenes, calcite, gypsum, amorphous carbon, and graphite were also detected. XRD measurements, and μXRF analyses were used as complementary techniques to obtain mineral and chemical compositions. Hematite, anatase, calcite, plagioclase feldspar, and illite were present in potsherds, suggesting pottery produced from illitic clays fired at less than 850 °C under oxidizing conditions. Results further suggest that raw materials were sourced from or near local volcanic rock areas, and more broadly from metamorphic or sedimentary rocks and clays. Chemically, raw materials used for red coatings are different to those of the ceramic bodies. Objects from most sites used the same raw material sources; however, some sites contain objects made from changing sources over time. Pot coatings exhibit polygonal cracks, and loosened cementation strongly suggesting that finely processed moist clays were fired to a biscuit form with no second stage firing process. The non‐destructive Raman experiments identified and characterized mineral phases, which helped understand manufacturing techniques. Overall the multi‐technique approach gave extensive information on the finds, helping to differentiate raw material sources and production technologies. This approach is an important and effective method for investigating archaeological finds. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

3.
A molded‐loose‐powder technique using a small powdered sample (100 mg) was developed for the X‐ray fluorescence analysis of 22 components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3, V, Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, and Pb) in ancient pottery. This loose powder specimen was prepared by pressing the small powdered sample into a sample holder, formed from a stainless steel disk (48‐mm diameter × 0.8‐mm height) with a hole (11‐mm diameter), by hand. Calibration standards were prepared by homogenizing chemical reagents containing these 22 analytes using the concentration ranges of 166 ancient potteries and three clay materials from Japan. The calibration curves of these benchmark mixtures exhibited a good linearity (correlation coefficient, r = 0.990–1.000), accuracy, and reproducibility compared with those of other synthesized specimens and three reference standards. The lower limits of detection were less than tens of mg kg?1 (e.g., 94 mg kg?1 for Na2O, 11 mg kg?1 for P2O5, 1.1 mg kg?1 for Rb, and 0.9 mg kg?1 for Y). Using the present method, we determined 22 components in two prehistoric potteries from Japan. The advantage of this method is that only a small amount of sample is required, which can be prepared easily and rapidly and reused for other analyses. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

4.
《X射线光谱测定》2003,32(6):413-417
Using energy‐dispersive x‐ray fluorescence analysis with an 125I ring source, it was possible to determine the concentration of several elements, such as Mn, Fe, Cu, Zn, Br, Rb and Sr, at the µg g?1 level in a microorganism (Mycobacterium fortuitum) and in nutrient medium. It was observed that the bacteria always incorporated a fixed amount of a given element even if the concentration in the nutrient medium was different. It was possible to contaminate the cells also with Zr. The sample preparation and irradiation process developed is a non‐destructive microorganism analytical method, as about 70% of the bacteria survived the measuring process. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

5.
X射线荧光光谱法测定硅酸盐中硫等20个主、次、痕量元素   总被引:39,自引:1,他引:39  
本文使用新研制的偏硼酸锂和四硼酸锂混合熔剂,在1000℃熔融制样,以X射线荧光光谱法测定硅酸盐等样品中的S,Na,Mg,Al,Si,P,K,Ca,Ti,Mn,Fe,Ba,Cr,V,Sr,Zr,Rb,Cu,Ni和Nb等20种元素,采用理论α系数和康普顿散射线作内标校正元素间的吸收-增强效应。其分析结果的精密度和准确度可与化学法相比  相似文献   

6.
In archeology, pottery represents an important class of artifacts giving information on the past human activity, the ecology, and ancient cultural groups. Some chemical analytic methods, including X‐ray fluorescent analysis, were adopted for the archeological study of pottery. However, these techniques also involve problems, including the destructive analysis of materials, and cannot analyze the original clay condition of pottery. To address this, we carried out nondestructive chemical analysis of 13 potsherds excavated from the Yaeyama Islands in the southern Japan archipelagos using X‐ray fluorescence microscopy. Two analytic methods were used, elemental mapping and multipoint spectral measurement, making it possible to obtain a visualized elemental distribution on potsherd surface and a detailed multipoint elemental composition of the same sample for the multivariate statistical analysis. In this study, the visualized images suggested that calcium particles were mixed to temper the materials, and their size and quantity differed between potsherds, whereas the uniformity of clay substrate, including the quantities of iron and silicon on multipoint measurement, was a characteristic of each potsherd. Therefore, principal component analysis and nonmetric multidimensional scaling analysis of the potsherds suggest that the differences between the Yaeyama Islands in terms of pottery manufacturing technology are due to chronological factors in this case. Our method represents an effective new approach to the pottery study for technological change.  相似文献   

7.
The chemical characterization of the black gloss on ancient pottery is, since several years, the object of different scientific investigations. Among the different typologies of black gloss, the Attic one is the most refined, because it is prepared by using a fine suspension of an illitic clay applied on the surface of the clay body so that, after an oxiding‐reducing‐oxiding firing cycle at high temperature (800–950 °C), it reaches the typical shiny black aspect. Red figure vases were largely produced in South Italy often reaching a high artistic level. This is the case of the Sicilian red figure vases, sometimes called ‘Sicelioti’, whose production began in Sicily around the end of the fifth century BC and continued until the beginning of the third century BC . The aim of this work is to submit and compare a selection of data related to the chemical composition of the surface black gloss of some Attic and Sicilian red figure vases: This has been investigated, and a chemical‐based discrimination has been proposed. The non‐destructive particle‐induced X‐ray emission‐alpha portable spectrometer was used. The results, carried out in situ at the ‘Paolo Orsi’ Archaeological Museum in Syracuse (Sicily), together with the ones recently obtained in similar analyses at the Archaeological Museum of Catania University, confirmed the compositional stability of Attic vase black gloss and indicated that in a well‐defined time period, the chemical composition of the Sicilian black gloss decorations is very stable and superimposable with that of the contemporary Attic artifacts. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
In a population sample of residents of Novosibirsk between the ages of 45 and 69, the complex of the following chemical components of blood is determined by SR XRF: K, Ca, Fe, Cu, Zn, Ge, Se, Br, Rb, Sr, Zr, and Pb. Risk factors of chronic noncommunicable diseases are determined: obesity, arterial hypertension, dislipidemia, and their associations with chemical elements Ca, Cu, Rb, Y, and Pb.  相似文献   

9.
This paper presents the results of X‐ray fluorescence (XRF) analysis of bricks sampled from historical places in Pernambuco, a state in the northeastern region of Brazil. In this study, twenty bricks found in historical sites were analyzed. Two bricks made in the 17th century, presumably used as ballast in ships coming from Holland, five locally manufactured bricks: one from 18th century, three from 19th century, and one from 20th century, and thirteen bricks collected from a recent Archeological investigation of Alto da Sé, in the town of Olinda. Qualitative determination of the chemical elements present in the samples was undertaken using a self‐assembled portable XRF system based on a compact X‐ray tube and a thermoelectrically cooled Si‐PIN photodiode system, both commercially available. X‐ray diffraction analysis was also carried out to assess the crystalline mineral phases present in the bricks. The results showed that quartz (SiO2) is the major mineral content in all bricks. Although less expressive in the XRD patterns, mineral phases of illite, kaolinite, anorthite, and rutile are also identified. The trace element distribution patterns of the bricks, determined by the XRF technique, is dominated by Fe and, in decreasing order, by K, Ti, Ca, Mn, Zr, Rb, Sr, Cr, and Y with slight differences among them. Analyses of the chemical compositional features of the bricks, evaluated by principal component analysis of the XRF datasets, allowed the samples to be grouped into five clusters with similar chemical composition. These cluster groups were able to identify both age and manufacturing sites. Dutch bricks prepared with different geological clays compositions were defined.  相似文献   

10.
A low‐dilution, undersized (12.5 mm diameter) glass–bead technique was developed for X‐ray fluorescence determination of 34 components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Hf, W, and Pb) in precious silicic samples for geochemistry and archeology. This preparation was consolidated based on the properties of the specimen, including disk formability and detachability from a small crucible, through variation of the amounts of the two samples (basaltic and granitic rocks) and releasing reagent. The specimen was prepared by fusing a mixture of 200 mg of powdered sample, 200 mg of lithium tetraborate as a flux, and 60 µl of 18.42 mass% lithium chloride solution as a releasing agent in a small platinum crucible. Calibration curves were drawn using synthetic calibration standards, which were prepared by compounding chemical reagents, such as oxides, carbonates, and diphosphates containing analytes. The calibration curves showed good linearity with correlation coefficient values greater than 0.990. Using the proposed method, we determined 34 components in five igneous rock reference samples. The results were in agreement with the recommended values, accounting for uncertainties. With this method, preparation requires only small amounts of the powdered sample and alkali flux; however, still allowing for determination of many analytes, which is advantageous when dealing with limited quantities of precious samples. The present method has potential applications in the chemical characterization of various geological and archeological samples. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
Environmental studies have revealed significant contributions of vehicular exhaust emissions to high pollution levels in urban dwellings. The levels and sources of heavy metal contaminations of some major roads in Accra have been investigated in this work. Street dust samples collected from four major roads in Accra (Mallam Junction‐Weija road, John Teye‐Pokuase road, Tema Motorway and Tetteh Quarshie Interchange in Accra) were analysed for their elemental concentrations using energy‐dispersive X‐ray fluorescence. Twenty elements were identified: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr and Pb. Significant concentration levels were obtained for K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Br, Rb, Sr, Y, Zr and Pb in all the samples and were used for the source identification. Enrichment factors and principal component analysis were used to verify the anthropogenic contribution to road dust. Results obtained for the enrichment factors showed moderate enrichment for V, Cr and Cu, while Zn, Br, Zr and Pb were significantly enriched. Principal component analysis identified four sources and their contributions to the elemental contents in the road dust. Natural crust, brake wear, tyre wear and vehicle exhaust emission were the four sources identified. The contribution of vehicular non‐exhaust emissions to heavy metal contamination in the road dust was found to be greater than that of exhaust emissions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

12.
《X射线光谱测定》2005,34(2):128-130
Punch‐marked coins are the oldest known numismatic objects used in ancient India. Seven punch‐marked silver coins were analysed by using the non‐destructive multi‐elemental PIXE technique. A 3 MeV proton beam from a pelletron accelerator was used for irradiation of these samples to obtain the spectral data and GUPIX software was employed to derive the elemental concentrations. The results reveals that silver, copper, gold and lead are significant constituents of the punch‐marked silver coins and there are also traces of elements such as Ti, Cr, Mn, Fe, Co, Ni, As and Y, which seems to imply that PIXE can be used effectively for the non‐destructive quantitative analysis of ancient coins. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

13.
X射线荧光光谱法测定橄榄岩主次痕量元素   总被引:11,自引:0,他引:11  
本文采用熔融玻璃片和粉末压片法制样,用理论a系数和散射线内标法校正元素间的效应,  相似文献   

14.
The possibilities of performing non‐destructive elemental microanalysis with synchrotron radiation by means of homemade polycapillary optics are described. Using fiber glass technology, monolithic polycapillary half‐lenses were made by drawing packages of glass capillaries at high temperature in a heating furnace. The performance of polycapillary half‐lenses with different geometries was evaluated. A gold knife‐edge scanned at the output of the lenses was used to determine the spot size at different distances. Measurements of photon flux impinging on the entrance end of the lenses and photon flux leaving the lenses were used to obtain the transmission efficiency. The polycapillary half‐lens made in our laboratory was used in a series of XRF microanalysis tests using white beam. The overall efficiency of the system was studied by means of establishing detection limits for various elements in an organic sample. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

15.
This work presents two applications of XRF in archaeometry. The first case involved a female mummy from the Roman period, which is considered one of the most important pieces of the National Museum (Rio de Janeiro), because of its unconventional embalming with legs and arms swathed separately. The objective was to characterize the elemental composition of the pigments found in the sarcophagus cartonage and to verify whether they were in accordance with those used by Egyptian craftsmen in the cited period. The elements identified were Si, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Sr, Hg, and Pb. In the second case, the composition of decorated pottery pubic covers (tangas) from the Marajoara culture was evaluated using EDXRF. Ceramics from the Marajó Island (at the mouth of Amazon River, Brazil) represent one of the most beautiful and sophisticated styles of the pre‐Columbian art. Decorated tangas were used by Marajoara girls probably as part of puberty rites. The analyzed samples were two tangas and four fragments from the National Museum's collection. One fragment (sample 22245) presented a different design pattern that seemed to indicate a different provenance. The elements identified were K, Ca, Ti, Mn, Fe, Cu, Zn, Ga, Rb, Sr, Y, Zr, and Pb. Multivariate statistical analysis was applied to the results. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

16.
Micro X-ray fluorescence spectrometry (μXRF) is a standard technique used for the elemental analysis of glass fragments in forensic casework. The glass specimens encountered in casework are usually small (<1 mm), thin fragments that are partially transparent to the exciting X-ray beam. In addition to providing fluorescence from the small glass fragments, the primary beam X-rays can scatter within the chamber and provide noise in the measurements. To reduce scatter from the sample stage, the fragments are typically mounted on a thin plastic film and raised on an XRF sample cup (≤3 cm in height). However, at these heights, there may still be significant scatter from the sample stage, which adversely affects the signal-to-noise ratio (SNR) and the limit of detection (LOD). A plastic mount was designed and 3D-printed in-house to allow fragments to be raised as high as possible from the sample stage, thereby minimizing stage scatter. Most elements detected in glass showed an improvement in the SNR when using the 3D-printed mount for analyses. The greatest improvement (>30%) was observed for lower atomic number elements (Na and Mg) and higher atomic number elements (Sr and Zr). Another simple method to improve SNR is the use of primary beam filters; when using primary beam filters during analyses, elements with characteristic lines in the high-energy range (Rb, Sr, and Zr) showed the greatest improvement (>70%) in SNR. The impact of both strategies for the improvement of SNR is presented here.  相似文献   

17.
The Qβ-values of99Rb,99,100Sr and100Y have been measured for the first time at the mass separator OSTIS of the ILL; for99Y,99,100Zr and100Nb, the results of earlier experiments were confirmed with reduced experimental errors. The two-neutron binding energies derived from the experimental Qβ-values clearly indicate that the nuclei100Sr and100Y are strongly deformed.  相似文献   

18.
A microprobe system has been installed on the nanoprobe/XAFS beamline (BL8C) at PLS‐II, South Korea. Owing to the reproducible switch of the gap of the in‐vacuum undulator (IVU), the intense and brilliant hard X‐ray beam of an IVU can be used in X‐ray fluorescence (XRF) and X‐ray absorption fine‐structure (XAFS) experiments. For high‐spatial‐resolution microprobe experiments a Kirkpatrick–Baez mirror system has been used to focus the millimeter‐sized X‐ray beam to a micrometer‐sized beam. The performance of this system was examined by a combination of micro‐XRF imaging and micro‐XAFS of a beetle wing. These results indicate that the microprobe system of the BL8C can be used to obtain the distributions of trace elements and chemical and structural information of complex materials.  相似文献   

19.
Synchrotron radiation X-ray fluorescence analysis is used to determine for the first time the absolute content and biological accumulation coefficients for a set of 21 chemical elements (K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Y, Mo, and Pb) in the fruits, leaves, bark, roots, and root nodules of the sea buckthorn (Hippophae rhamnoides L. ssp. mongolica Rousi). It is found that all sea buckthorn tissues accumulate Ti, Nb, Cr, and Zr more intensively than the global average for terrestrial phytomass. On the other hand, none of the examined parts of the sea buckthorn plants accumulated the toxic elements Pb and As.  相似文献   

20.
A particle‐induced X‐ray emission (PIXE) technique has been used in the determination of the principal components Pb, Zr and Ti and the substituting elements Sr, Cr, Nb and La in lead zirconate titanate ceramics. In general, precision of analysis was concentration dependent from each element under study. For Pb, precision varied between 0.13% and 0.16%, at higher concentration of 59.32–64.5%. It was around 6–9% for Sr, Cr and Nb at concentrations of 1% or lower. Particular attention was devoted to the estimation of the analysis trueness. With this purpose, three methods were applied: (1) comparison of PIXE and inductively coupled plasma optical emission spectrometry concentrations, (2) recovery study and (3) comparison with a laboratory standard. Trueness of analysis was around 100 ± 10% for the evaluated elements Pb, Zr, Ti, Sr and Cr. The expected stoichiometry and elemental composition homogeneity of a wide group of produced ceramics were confirmed by the PIXE technique. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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