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1.
本文研究了用X-射线荧光光谱法测定密闭鼓风炉粗锌中铅、锌、铁和镉等元素,样品从炉前取出后铸成一定形状,被测表面经抛光后直接测定,不经化学处理。用经验系数法校正基体效应。用人工模拟制备标准,其浓度与X-射线强度的线性相关系数均在0.98以上,标准偏差小于0.0056;相对标准偏差小于2.41%。测定结果与化学结果相符。  相似文献   

2.
The portable XRF spectrometer has been applied in situ for the non-destructive elemental mapping of the pigment components of the XV c. mural painting and frescos of the Little Christopher chamber in the Main Town Hall of Gdańsk, Poland. For a sufficiently large data collection the principal component analysis (PCA) was applied in order to associate the most intense lines of the elements Ca, Cu, Fe, Pb, and Hg in the XRF spectra with the palette of colors: white, brown, green, blue, red, yellow, and black observed in the painting. This allowed to limit the number of extractions of the micro-samples for the complementary Raman measurements thus assuring the practically non-destructive character of the entire analysis. The reliable identification of the pigment compositions was based on coincidence of the XRF, PCA and the Raman results which confirmed the presence of the chalk, malachite, azurite, red lead, mars red, mars yellow and candle black in the historical paints, except of the carbon-based black pigment being out of the XRF detection range. Different hues of the green paint were specified and the variety of the red and brown ones was ascribed to compositions of the Pb- and Fe-based red pigments (Fe2O3 and Pb3O4) with addition of the vermilion (HgS) and carbon black, in agreement with literature. The traces of elements: Ba and Sr, Sb and Mo, and also Cd, were ascribed to the impurities of Ca, those of some ochre pigments, and to the soluble Cd salts, respectively.  相似文献   

3.
ICP-AES测定7种花茶中8种微量元素的含量和溶出率   总被引:2,自引:1,他引:1  
汤长青  朱芳坤 《光谱实验室》2010,27(4):1415-1418
采用微波消解样品,电感耦合等离子体-原子发射光谱法测定了金银花、玫瑰茄、玉蝴蝶、仙人草、菊花、薰衣草、腊梅等7种花茶中Fe、Mn、Cu、Zn、Ni、Cr、Cd和Pb等元素的含量及其溶出率。结果表明,花茶中Fe含量较高,重金属Cr、Cd和Pb含量普遍较低,花茶中Cu、Zn、Mn和Ni的溶出率相对较高,Fe的溶出率较低,有害的重金属Cd、Pb和Cr的溶出率很低,此测定结果可为探讨花茶的保健作用与微量元素的相关性提供科学数据。  相似文献   

4.
Optical coherence tomography (OCT) has been shown to have potential for important applications in the field of art conservation and archaeology due to its ability to image subsurface microstructures non-invasively. However, its depth of penetration in painted objects is limited due to the strong scattering properties of artists’ paints. VIS–NIR (400–2,400 nm) reflectance spectra of a wide variety of paints made with historic artists’ pigments have been measured. The best spectral window with which to use OCT for the imaging of subsurface structure of paintings was found to be around 2.2 μm. The same spectral window would also be most suitable for direct infrared imaging of preparatory sketches under the paint layers. The reflectance spectra from a large sample of chemically verified pigments provide information on the spectral transparency of historic artists’ pigments/paints as well as a reference set of spectra for pigment identification. The results of the paper suggest that broadband sources at ~2 μm are highly desirable for OCT applications in art and potentially material science in general.  相似文献   

5.
This research presents the contents of Ca, Fe, Zn, Br, Rb, Sr and Pb in lichen samples used as biomonitors of air pollution collected in Havana. Statistical comparisons were made among the results obtained in three campaigns during three years. Two X‐Ray Fluorescence (XRF) methods were used, employing for excitation an annular 109Cd source and a Mo X‐ray tube with a molybdenum secondary target. In both cases, matrix effects were corrected by the use of normalization for the Compton scattered peak; in this way the determination is more efficient. For quality control of the results, biological Certified Reference Materials were analyzed and were made comparisons between XRF, Inductively Coupled Plasma‐Atomic Emission Spectrometry and Flame Atomic Absorption Spectrophotometry. No significant differences were found between the different techniques. The elemental distribution patterns obtained for each metal were associated with different pollution sources, thus contributing to the assessment of air pollution in Havana. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

6.
A dual imaging approach, combining magnetic resonance imaging to localize lesions and synchrotron rapid scanning X-ray fluorescence (XRF) mapping to localize and quantify calcium, iron and zinc was used to examine one case of recent stroke with hemorrhage and two cases of ischemia 3 and 7 years before death with the latter showing superficial necrosis. In hemorrhagic lesions, more Fe is found accompanied with less Zn. In chronic ischemic lesions, Fe, Zn and Ca are lower indicating that these elements are removed as the normal tissue dies and scar tissue forms. Both susceptibility and T2* maps were calculated to visualize iron in hemorrhages and validated by XRF Ca and Fe maps. The former was superior for imaging iron in hemorrhagic transformation and necrosis but did not capture ischemic lesions. In contrast, T2* could not differentiate Ca from Fe in necrotic tissue but did capture ischemic lesions, complementing the susceptibility mapping. The spatial localization, accurate quantitative data and elemental differentiation shown here could also be valuable for imaging other brain tissue damage with abnormal Ca and Fe content.  相似文献   

7.
微区无损分析可提供物质组成元素的原位分布信息,以揭示物质形成条件、元素动态分布过程与相互作用机理、生物代谢作用等。文章报道了实验室型微区X射线荧光(μXRF)光谱仪的研发和元素生物地球化学动态分布过程研究结果。μXRF光谱仪采用15 μm光斑的聚束毛细管X射线透镜为激发源,选用分辨率为135 eV的硅漂移探测器(SDD),样品和探测器间角度可调,使之可进行异型样品如地质样品的原位分析,利用五轴自控实现样品时空四维元素分布测定。利用该μXRF光谱仪测定了矿物-生物膜间的元素迁移和玉米种发芽过程中的元素分布,发现(1)生物膜可吸附、富集毒性元素铅,是重金属的重要汇集地,最大富集系数1.7。(2)生物膜是金属从固态矿物相经水相进入生态系统的重要途径。(3)在玉米种子中,可检测到K,Ca,Mn,Fe,Cu,Zn和Pb。Zn主要在胚乳中分布,胚中有少量Zn存在;在胚乳和胚中存在微量Fe;胚乳中存在微量Pb,胚中未观测到Pb。(4)经含Pb溶液浸泡发芽后,K在玉米种中胚和胚乳中部分富集,Fe分布在种皮和胚乳中,Cu和Zn主要在胚乳中分布;Pb主要在胚根、胚轴和胚芽中分布,且Pb在新生根中高度富集。研究表明,在种子萌发阶段,Pb等毒性元素可被植物滞留于根部,制约了其向地上部的转移,从而揭示了植物对毒性元素的耐受机制。  相似文献   

8.
Evidence for the alteration of the yellow paints in Henri Matisse’s Le Bonheur de vivre (1905–1906, The Barnes Foundation) has been observed since the 1990s. The changes in this iconic work of Matisse’s Fauvist period include lightening, darkening, and flaking of the yellow paints. Handheld X-ray fluorescence (XRF) and multispectral imaging surveys reveal that the degradation is confined to cadmium yellow (CdS) paints. The discoloration of cadmium yellow paints in Impressionist, Post-Impressionist and early modernist work from the 1880s through the 1920s has been ascribed to the photo-oxidative degradation of CdS. Preliminary investigations of the degraded yellow paints in this work involved Cd LIII-edge X-ray Absorption Near Edge Spectroscopy (XANES) at the Stanford Synchrotron Radiation Light Source (SSRL Menlo Park, California) and Scanning Electron Microscopy-energy dispersive X-ray analysis (SEM-EDS) at the Winterthur Museum Scientific Research and Analysis Laboratory. To determine if the visual changes in the paints did in fact indicate photo-oxidative degradation and if different chemistries could be observed for the lightened versus darkened regions, synchrotron radiation-micro Fourier Transform InfraRed (SR-μFTIR) spectroscopy, X-ray Fluorescence (SR-μXRF) mapping and micro X-ray Absorption Near Edge Spectroscopy (μXANES) mapping at the Cd LIII-edge of the altered paint cross-sections were carried out at the European synchrotron radiation facility (ESRF, Grenoble, France) beamline ID-21. The goal is to elucidate the discoloration mechanisms observed in the paint using elemental and speciation mapping. The μXANES mapping and SR-FTIR imaging showed a substantial enrichment of CdCO3 in the off-white surface crust of the faded/discolored CdS paint. This suggests that the CdCO3 is present as an insoluble photodegradation product rather than solely a paint filler or starting reagent. Additionally, oxalates and sulfates were found to be concentrated at the alteration surface.  相似文献   

9.
锌冶炼浸出渣是湿法炼锌工艺产出的冶炼固废渣,占锌冶炼固废产出总量的75% 以上,因含有Zn,Cu,Pb,Ag,Cd和As等多种有价金属元素,其资源化利用潜力巨大.然而由于其成分含量不稳定,检测精度不足等原因,导致关键元素的资源转化效率难以保证,因此对浸出渣关键资源组分的精准定量分析在锌冶炼行业绿色发展方面具有重大意义....  相似文献   

10.
原子吸收光谱法测定紫菜中微量元素   总被引:5,自引:1,他引:4  
王凤平 《光谱实验室》2006,23(4):694-697
用原子吸收光谱法对紫菜中铜、铁、锰、镁、钙、锌、铅、镉8种微量元素含量进行测定,方法的精密度、回收率符合分析要求.测定结果表明:紫菜中含有丰富的人体必需的微量元素,而铅、镉等有害元素含量很低,作为食用蔬菜对人体补充微量元素有较高的利用价值.  相似文献   

11.
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   

12.
Abstract

Diagnostics of experimental zinc intoxication by industrial emission from the zinc and copper factory on the basis of accumulation and distribution of Zn, Cu, Fe, Mo, Se, As, Cd and Pb in the liver, kidneys, spleen, musculature, uterus, ovaries, chorioidea of eye and bones in seven experimental and five control sheep is described. A daily intake of Zn from industrial emission was 6158.07 mg/an experimental animal. The first animals died of zinc intoxication on d 42 and the last one on d 58 of the experiment. The highest concentration of zinc in experimental animals died of zinc intoxication was in the liver dry matter (1167.3 ± 314.1 mg.kg?1) and in the kidneys (1049.5 ± 283.7 mg.kg?). Significantly higher Zn content compared with the control sheep was confirmed in the experimental ones in the liver, kidneys, ovaries and eye chorioidea (p < 0.01). The liver, kidneys, uterus were the organs with the highest Cu accumulation. The highest Fe accumulation was found in the spleen, kidneys and liver. Distribution of Mo and Se in the organs analyzed in experimental and control animals was similar. The industrial emission intake from the copper and zinc factory manifested in statistically higher accumulation of As, Cd and Pb in the organism of experimental sheep than in control ones (p < 0.05; methallothionein within the process of resorption, retention and metabolic activity (Kojima et al., 1991). The negative interaction between Zn and Pb is, above all, within the process of absorption (Elsenhans et al., 1978). Comparison of cumulation and distribution of As, Cd and Pb in the organs of experimental and control sheep revealed that in experimental animals the significant differences reflected the intake of these elements from industrial emission. Possibility for interaction relations with Zn, regarding the presence of the other toxic elements, appeared to be secondary.  相似文献   

13.
主要采用电感耦合等离子体质谱技术(inductively coupled plasma mass spectrometry,ICP-MS)测定了安徽茶园茶叶中四种大量元素(Ca,K,Mg,P)和七种微量元素(Al,Mn,Fe,Cu,Zn,Cd 和Pb)含量,并进行了生物富集分析。结果表明,嫩叶中Ca,K,Mg 和 P的含量最高(Ⅰ, >3.0 mg·g-1),Al,Mn,Zn 和 Fe的含量次之(Ⅱ, 0.2~3.0 mg·g-1),Cu,Pb 和 Cd的含量最低(Ⅲ, <0.05 mg·g-1);而老叶中含量最高的是Ca,K,Mg 和Al(Ⅰ, >3.0 mg·g-1),P,Mn,Zn 和 Fe的含量次之(Ⅱ, 0.2~3.0 mg·g-1),Cu,Pb 和 Cd的含量最低(Ⅲ, <0.05 mg·g-1)。其中,P和Mn是茶叶中富集能力最强的;此外,Cu, Pb和Cd的含量低于相关的限量标准。聚类分析结果表明舒茶早和龙井43两个品种之间矿质元素的组成没有显著性的差异。  相似文献   

14.
Human beings have had an inherent urge to leave their mark in the form of works of art since prehistoric times. This has driven the quest for new and better pigments with which to make paints. This paper describes the origins and composition of earliest earth pigments used by primitive man to decorate the walls of caves through to the synthetic pigments developed in more recent times. Despite modern technology, the artist's palette remains a mixture of the pigments used by cave artists, natural pigments used in the middle ages, and modern organic compounds.  相似文献   

15.
采用微波消解-FAAS测定了皖南休宁县茶园不同深度土壤中的矿质元素Cu、Cd、Mn、Zn、Fe、Pb的含量,分析了不同深度土壤中矿质元素的分布特征,结果表明,皖南土壤中矿质元素Cu、Cd、Mn、Zn、Pb 5元素含量随土壤深度呈递减趋势,土壤表层的矿质元素(Cu、Cd、Mn、Zn、Pb)含量高于深层的,这与施肥有关,土...  相似文献   

16.
密封消解ICP-AES和ICP-MS测定中日两国茶叶中23种矿质元素   总被引:18,自引:4,他引:14  
收集了13种中国茶叶和6种日本茶叶,在进行密封消解后,采用电感耦合等离子体发射光谱法(ICP-AES)和电感耦合等离子体质谱法(ICP-MS)测定了茶叶中Al,Ba,Ca,Cd,Ce,Co,Cr,Cs,Cu,Fe,La,Mg,Mn,Na,Ni,Pb,Rb,Sb,Sr,Th,U,Y和Zn等23种矿质元素的含量,并用茶叶标准参考物质(GBW07605)评价了分析方法的准确度。研究结果表明:密封消解有助于获得较为准确的茶叶中矿质元素含量的分析结果;与日本茶叶相比,中国茶叶中Cd,Co,Cr,Cs,Fe,Pb,Rb,Sb,Th,U和Zn等元素含量显著偏高(P<0.05),预示大气重金属污染程度中国较日本严重。另外,还发现茶叶中一些矿质元素含量之间有很强的线性相关性。  相似文献   

17.
X‐ray diffraction (XRD), energy dispersive spectrometry (EDS), x‐ray imaging (XRI) and scanning electron microscopy (SEM) techniques were applied to characterize and differentiate surface paintings of archeological pottery from the Aguada Ambato and Portezuelo styles (Catamarca, Argentina). Standard procedures are not always appropriate for such samples (paint layers are porous, nonplanar and discontinue). Image processing is necessary when chemical contrast is not discriminated. Soft x‐ray lines (e.g. Fe L) are more revealing because those detected come from shallower depths, clearly depicting the composition of the paint layer. These styles differ in mineralogy and chemistry suggesting that they are two distinctive entities not only on their designs but also on the materials chosen and the technology used. Aguada Portezuelo paints contain Ca (white), Fe? Mn (black), Fe? Mn? Ca (dark reddish) and Fe? Ca (reddish). The white ones correspond to gehlenite, a firing product (possible firing temperature ≥900–1000 °C); calcite and CaO occur in cases of firing temperatures <900 °C. Aguada Ambato presents difficulties for paint discrimination; only EDS spectra show slight differences. White paint from Tricolor Ambato contains mainly Pb‐phases (hatchite, anglesite, plumalsite), reddish paint resembles the paste (~Fe, hematite); reddish surfaces may have not been painted but polished. Black paint has scarce Mn–minerals. On Black Incised sherds no particular phase was identified suggesting possible organic pigments or resulting from the firing technique. The chemistry and mineralogy of the paste almost always overlap that of the paints; painted layer is irregular and partially worn by years of burial. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
为比较金银花、山银花中金属元素的含量是否存在差异,用王水对金银花、山银花进行消解,用火焰原子吸收光谱法测定了它们中Na、Ca、Mg、Zn、Fe、Co、Cr、Ni、Mn、Sn、Cu、Cd、Pb、Ag、Au等金属元素的含量.发现金银花、山银花中Na、Ca、Fe、Ni、Mn元素含量差异较大,他们所含的重金属元素超标.  相似文献   

19.
采用湿法消解制样,运用ICP-AES法对广西产中药广豆根和千斤拔中的常最及微量金属元素的含量进行了测定.研究了仪器的工作条件,各元素的分析线和检测限,元素的含量平均值和标准差.结果表明广豆根中含Cu,Zn,Fe,Mn,Cr等微量金属元素和Ca,Mg,Na,K常量金属元素;千斤拔中含Cu,Zn,Fe,Ni,Mn,Cr等微量金属元素和Ca,Mg,Na,K常最金属元素;两者都不含Sn,Pb,Cd等对人体有害的元素.相对标准偏差值均小于5%.研究中还发现广豆根和千斤拔中Zn/Cu值分别为6.4和5.7左右,呈锌高铜低的现象,与癌症患者血清中锌低铜高的现象相反,而与抗癌中药中微量元素的含量锌高铜低的现象一致,这对理解这些抗癌中药的药理作用有一定的启示作用.  相似文献   

20.
39例血清样品用酸消化和酸稀释制备待测液,ICP-AES相同条件下同时测定Fe、Zn、Cu、Cr、Cd和Pb。统计结果表明,消化法测得Fe、Zn和Cr显著高于稀释法,Cd低于稀释法;Cu和Pb两法测得结果无显著差异。相关分析表明,两法测得Fe、Cu、Zn和Cr正相关;Pb和Cd不相关。ICP-AES测定动脉粥样硬化和健康对照组间人血清六种微量元素稀释法无显著差异,而消化法测得组间不同程度存在显著性差异。建议采用消化法制备待测液较好。  相似文献   

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