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Cadmium concentration in lake sediments is determined by suspending the solid samples in a solution containing 5% (v/v) concentrated nitric acid and 0.1% (v/v) Triton X-100. Three modifiers were tested for the direct determination. The furnace temperature programmes and appropriate amount for each modifier were optimised to get the highest signal and the best separation between the atomic and background signals. The drying stage is performed by programming a 400 °C temperature, a ramp time of 25 s and hold time of 10 s on the power supply of the atomiser. No ashing step is used and platform atomisation is carried out at 2200 °C. W–Rh permanent modifier combined with conventional modifier by delivering 10 μl of 0.50% (w/v) NH4H2PO4 solution was the best chemical modifier for cadmium determination. This modifier also acts as a liquid medium for the slurry, thus simplifying the procedure. Calibration is performed using aqueous standards in the 1–5 μg l−1 range. The optimised method gave a limit of detection of 0.56 ng ml−1, characteristic mass of 10.1±0.8 pg for aqueous standard, 9.6±0.7 pg for slurry samples containing different Cd concentrations and good precision (7.6–5.2%). The method was validated by analysing four certified reference lake sediment materials: LKSD-1, LKSD-2, LKSD-3 and LKSD-4; satisfactory recoveries were obtained (90.0–96.3%) and no statistical differences were observed between the experimental and the certified cadmium concentration. The developed methodology was used to determine cadmium in three ‘real’ sediment samples from lakes in the area of Wielkopolski National Park, Poland. 相似文献
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Maria Chudzinska Anna Debska Danuta Baralkiewicz 《Accreditation and quality assurance》2012,17(1):65-73
A method for simultaneous ICP-MS determination of 13 elements in three types of honey from Poland is described. The method
was validated, and the uncertainty budget was set up. The results obtained for the relative expanded uncertainties U
rel (k = 2) were 15.1% for Al, 18.6% for B, 18.8% for Ba, 7.9% for Ca, 24.4% for Cd, 7.24% for Cu, 7.9% for K, 4.8% for Mg, 8.3%
for Mn, 12.7% for Na, 14.9% for Ni, 12.5% for Pb and 13.4% for Zn. Traceability of the measurement results was established
based on the use of the corn flour CRM INCT-CF-3 and the apple leaves CRM SRM 1515 and by analyzing spiked samples. Recovery
rates between 94% (Zn) and 107% (Na) were found. The detection limits of all elements studied showed the suitability of the
procedure for routine analyses. Summarizing it can be concluded that the described analytical procedures to measure the mass
fractions of 13 elements in honey samples with established traceability and evaluated uncertainty allow to obtain reliable
and internationally comparable results. 相似文献
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Danuta Baralkiewicz Malgorzata Kózka Hanka Gramowska Barbara Tomaszewska Konrad Wasinkiewicz 《International journal of environmental analytical chemistry》2013,93(12):901-908
The comparative determination of lead in plant samples by two atomic spectrometric techniques is reported. At first, slurry sampling electrothermal atomisation atomic absorption spectrometry (ETAAS) was applied. The results obtained were compared with those found after a wet digestion procedure by flame atomic absorption spectrometry (FAAS) or ETAAS. The accuracy of the studied methods was checked using a certified reference material (CL???1 CRM, Cabbage Leaves). The recovery of lead was 90% for slurry sampling ETAAS, and 86.6% for liquid sampling ETAAS. The advantages of the slurry sampling ETAAS method are the simplicity of sample preparation and very good sensitivity. 相似文献
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Danuta Baralkiewicz Małgorzata Kozka Piotr Kachlicki Aneta Piechalak Barbara Tomaszewska 《International journal of environmental analytical chemistry》2013,93(13):979-988
Plants exposed to heavy metals activate a detoxification system capable of chelating and transporting these harmful ions to vacuoles. Phytochelatins–low molecular weight oligopeptides containing thiols such as glutathione and cystein–have been reported to play a very important role in this respect. High performance liquid chromatography coupled to the electospray ion trap mass spectrometer (HPLC-ESI-IT-MS) was used for identification of phytochelatins induced by Cd2+ and Pb2+ in roots, stems and leaves of pea (Pisum sativum L.) and yellow lupin (Lupinus luteus L.). This approach enabled unambiguous identification of phytochelatins in plant tissues and detection of phytochelatins and homophytochelatins in reduced as well as in oxidised form. Significant differences were detected in phytochelatin relative amounts and profiles in different parts of plants treated with heavy metals. Roots of both plant species contained mainly reduced phytochelatins, reduced and oxidised forms of these peptides were observed in stems in similar amounts, whereas only the oxidised phytochelatins were present in leaves. 相似文献
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In this work twelve elements (Al, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were determined in 30 honey samples from various locations within Poland and in two different types of honey--rape and honeydew. Trace elements (Al, B, Cr, Mn and Ni) were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), however, major elements (Ca, K, Mg, Na) and Cu, Fe, Zn were determined by Flame Atomic Absorption Spectrometry (F-AAS). Cluster analysis of honey data revealed that the origin of honey samples correlated with their chemical composition. It was shown that rape honey includes lower amounts of manganese than honeydew honeys. Also honeydew honey includes much higher concentrations of Al, Cu, K, Fe and Ni in comparison with rape honey. Moreover honeydew honey was found to have a higher mineral content, which reflects sources from which the honey is composed. Trace element analysis showed that the differences in the values found in honey samples could be used as evidence of the quality of honey samples. 相似文献
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Baralkiewicz Danuta El-Sayed Usama Filipiak Marian Gramowska Hanka Mleczek Miroslaw 《Central European Journal of Chemistry》2004,2(2):334-346
Slurry sampling electrothermal atomic absorption (SS ETAAS) was applied to the development of a sensitive and precise method
for selenium determination in infant foods without sample pretreatment. Suspensions prepared in a medium containing 0.1% Triton
X-100, 0.5 or 5% v/v concentrated HNO3 were directly introduced into the furnace. The accuracy of the procedure was confirmed by analysis of a standard reference
material and comparison with hydride generation atomic absorption spectrometric (HGAAS) procedure. The characteristic mass
is 44 pg and detection limit 0.43 μg·l−1. 相似文献
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