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X射线荧光光光谱分析 总被引:3,自引:0,他引:3
评述了我国在2007~2008年X射线荧光光谱,包括质子激发的X射线光谱的发展和应用,内容包括仪器、软件、仪器改造、仪器维护和维修、基础研究和分析方法研究及其应用. 相似文献
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A review of Total Reflection X-ray Spectrometry and related methods covering literature of four decades is presented. History, theory, instrumentation, sample preparation, and applications are summarized and some examples are given. New developments and trends are discussed with respect to emerging nano-technologies in all fields of sciences. 相似文献
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A total reflection X-ray fluorescence spectrometric method was developed for elemental analysis of natural biofilms grown on polycarbonate substrates in the Lake Velence. For the duration of 9 weeks long growing period, two substrates were removed weekly from the lake and investigated by analytical and algological methods. The total biomass production achieved its highest value after 7 weeks. Ca, Sr and Ti, as well as Fe, Mn, K and Zn showed their maximum concentrations in the biofilms after 5 and 6-7 weeks, respectively. The enrichment factors of the 6 weeks old biofilm for the detected seven elements amounted to 103-104. The recommended colonization time for biomonitoring of the Lake Velence is 6 weeks applying polycarbonate substrates. 相似文献
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In this paper, we introduce laser desorption X-ray ionization for producing ions from the previously undetected neutral species present during laser desorption mass spectrometry. Studies involving the laser desorption of simple sugars were conducted to illustrate the differences between spectra with and without the X-ray source. Ionization was made possible by placing a 200 mCi Am X-ray source directly into the ionization chamber of a time-of-flight mass spectrometer. 相似文献
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Peter Hoffmann Martin Kein Volker Scheuer Karl Heinrich Lieser 《Mikrochimica acta》1990,101(1-6):305-313
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 相似文献
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Analytical Methods Committee Royal Society of Chemistry 《Accreditation and quality assurance》2008,13(8):453-464
The reports of this series tabulate a number of features of analytical instruments that should be considered when making comparison between various systems. Scoring these features in a rational manner allows a scientific comparison to be made between instruments as an aid to selection. This is the XXIII report of the series and deals with instrumentation for portable X-ray fluorescence spectrometry. The Analytical Methods Committee has received and approved the following report from the Instrumental Criteria Sub-Committee. 相似文献
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Analytical Methods Committee 《Accreditation and quality assurance》2006,11(12):610-624
The reports of this series tabulate a number of features of analytical instruments that should be considered when making comparison
between various systems. Scoring these features in a rational manner allows a scientific comparison to be made between instruments
as an aid to selection. This is the XXth report of the series and deals with instrumentation for energy dispersive X-ray fluorescence
spectrometry. 相似文献
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The possibility of sulphur determination in uranium matrix by total reflection x-ray fluorescence spectrometry (TXRF) has been studied. Calibration solutions and samples of sulphur in uranium matrix were prepared by mixing uranium in form of a standard uranyl nitrate solution and sulphur in the form of Na2SO4 standard solution, prepared by dissolving Na2SO4 in Milli-Q water. For major element analysis of sulphur, it was determined without separation of uranium whereas for the trace level determinations, uranium was first separated by solvent extraction using 30% tri-n-butyl phosphate (TBP) in dodecane as an extractant. In order to countercheck the TXRF results, a few samples of Rb2U(SO4)3, a chemical assay standard for uranium, were diluted to different dilutions and sulphur content in these solutions were determined. The TXRF determined results for trace determinations of sulphur in these diluted solutions were counterchecked after addition of another uranium solution, so that sulphur is at trace level compared to uranium, separating uranium from these solution mixtures using TBP extraction and determining sulphur in aqueous phase by TXRF. For such TXRF determinations, Co was used as internal standard and W Lα was used as excitation source. The precision and accuracy of the method was assessed for trace and major element determinations and was found to be better than 8% (1σ RSD) and 15% at a concentration level of 1 μg/mL of sulphur measured in solutions whereas for Rb2U(SO4)3, these values were found to be better than 4 and 13%, respectively. 相似文献
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Paper documents from XVIII and XIX centuries were analyzed by energy dispersive X-ray fluorescence. The presence of Co (400 µg g− 1), Ni (300 µg g− 1), As (2000 µg g− 1) and Bi (200 µg g− 1) in Dutch papers and a Hespe watermarked paper allowed distinguishing them from the rest of the papers. The elemental composition of the ink present in these documents was also studied with the same technique and it was concluded that these elements could not be originated from ink dissemination. Strong positive Spearman correlations between Co, Ni, As and Bi were found in all Dutch and Hespe watermarked papers. Potassium and Ca are the predominant elements in all analyzed papers. Their concentration levels also allowed differentiating between Dutch and Hespe papers and the rest of the papers. Other elements such as Ti, Fe, Cu, Zn, Ba and Pb were also found. In this work a bibliographic research about the possible origin of each one of the mentioned elements present in the papers is also reported. 相似文献
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Martin A. Amberger Michael HöltigJosé A.C. Broekaert 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The use of slurry sampling total reflection X-ray fluorescence spectrometry (SlS-TXRF) for the direct determination of Ca, Cr, Cu, Fe, Mn and Ti in four boron nitride powders has been described. Measurements of the zeta potential showed that slurries with good stabilities can be obtained by the addition of polyethylenimine (PEI) at a concentration of 0.1 wt.% and by adjusting the pH at 4. For the optimization of the concentration of boron nitride in the slurries the net line intensities and the signal to background ratios were determined for the trace elements Ca and Ti as well as for the internal standard element Ga in the case of concentrations of boron nitride ranging from 1 to 30 mg mL−1. As a compromise with respect to high net line intensities and high signal to background ratios, concentrations of 5 mg mL−1 of boron nitride were found suitable and were used for all further measurements. The limits of detection of SlS-TXRF for the boron nitride powders were found to range from 0.062 to 1.6 μg g– 1 for Cu and Ca, respectively. Herewith, they are higher than those obtained in solid sampling and slurry sampling graphite furnace atomic absorption spectrometry (SoS-GFAAS, SlS-GFAAS) as well as those of solid sampling electrothermal evaporation inductively coupled plasma optical emission spectrometry (SoS-ETV-ICP-OES). For Ca and Fe as well as for Cu and Fe, however, they were found to be lower than for GFAAS and for ICP-OES subsequent to wet chemical digestion, respectively. The universal applicability of SlS-TXRF to the analysis of samples with a wide variety of matrices could be demonstrated by the analysis of certified reference materials such as SiC, Al2O3, powdered bovine liver and borate ore with a single calibration. The correlation coefficients of the plots for the values found for Ca, Fe and Ti by SlS-TXRF in the boron nitride powders as well as in the before mentioned samples versus the reference values for the respective samples over a concentration range from 2.5 to 1470 μg g– 1 were found to be 0.995, 0.991 and 0.997, respectively. 相似文献
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In recent years, there has been intensive research into the use of pyrolysis to process toxic plastics from waste electrical and electronic equipment (WEEE). During pyrolysis, the fate of the bromine and antimony content of the plastics is critical therefore, new and improved analytical techniques for analysing these elements in the pyrolysis products are being sought. In this work, the effectiveness of energy dispersive x-ray fluorescent spectrometry (EDXRFS) for the determination of bromine and antimony content of pyrolysis oils from waste electrical and electronic equipment have been tested. Samples were obtained by the pyrolysis of brominated high-impact polystyrene (Br-HIPS) and brominated acrylonitrile-butadiene-styrene (Br-ABS) at temperatures from 360 to 440 °C. The concentration range of both the bromine and antimony in the samples was very broad (0.05-17.94 wt% and 0.03-8.54 wt% respectively). The results from EDXRFS to those of more traditional and time consuming methods; bomb calorimetry combined with ion chromatography (EPA method 5050) for bromine and acid digestion combined with inductively coupled plasma-optical absorption spectrometry for antimony were compared.Based on our measurements, different statistical parameters were calculated for each analytical technique, which demonstrated that EDXRFS had been successfully applied to the determination of bromine and antimony concentration in the pyrolysis oils of Br-HIPS and Br-ABS. Errors resulting from matrix effects did occur, in particular correlations were found between the nitrogen content of the samples and the difference in bromine and antimony measured by EDXRFS and other methods (ion-chromatography and ICP-OES). However, these differences were found to be statistically insignificant, so we could conclude that EDXRFS is a suitable technique for analysing the bromine and antimony content of pyrolysis oils. 相似文献
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The electrodepositons of Te, Bi, Ni, Sb and Au from aqueous solution of pH = 1 on the cathode surface have been studied for X-ray fluorescence analysis (XRF). A special holder for a copper electrode has been constructed to perform the electrodeposition process on only one side of the electrode. After electrolysis, the copper electrode can be easily removed from the holder; after rinsing it with water and drying it can be analyzed by XRF. The proposed method of sample preparation and preconcentration of Te, Bi, Ni, Sb, Au provides suitable samples which are devoid of the negative and undesirable effects of XRF analysis, such as particle size and matrix effects. The influence of time on the deposition yield has been examined. The method of preconcentration is efficient. The inhomogeneity of the prepared specimens has been studied using internal standard method. The calibration is based on using synthetic standards, certified reference materials and standard addition method. The best results are achieved by the standard addition method. The agreement between results obtained with XRF analysis and certified values is satisfactory and indicates the usefulness of the proposed method for determination of Te, Bi, Ni, Sb and Au in anode slime. 相似文献