共查询到20条相似文献,搜索用时 781 毫秒
1.
K. Masumoto T. Ohtsuki Y. Miyamoto J. H. Zaidi A. Kajikawa H. Haba K. Sakamoto 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(3):495-500
Iodine, thallium and uranium were determined by photon activation analysis. Two electron linear accelerators were used for
the analysis of several kinds of environmental, biological and geochemical reference materials under different irradiation
conditions. Both analytical results for iodine were in good agreement with each other but not with literature values in the
case of environmental samples. The results of thallium and uranium agreed well with their reference values. The detectable
concentration levels of iodine, thallium and uranium were almost 0.3μg/g. 相似文献
2.
Liuxing Feng Liandi Ma Jun Wang Hai Lu 《Analytical and bioanalytical chemistry》2010,396(8):3051-3057
Two reference materials, at relatively low and high concentrations (GBW08404 and GBW08405), for analysis of the mass fractions
of Cd, Cr, Hg and Pb in polypropylene were developed. The reference materials were prepared by doping blank polypropylene
base material with Cd, Cr, Hg and Pb in the form of oxides, salts or pigments. Homogeneity and stability studies were performed
by inductively coupled plasma mass spectrometry. The certification of the four analytes was carried out by isotope-dilution
mass spectrometry (IDMS) with microwave-assisted digestion. Combined uncertainties were calculated from the IDMS uncertainty
evaluation budget and the uncertainty of the homogeneity. The mass fractions of Cd, Cr, Hg and Pb of the two certified reference
materials (CRMs) were from 8 to 1,000 mg kg−1. The two samples were also used in an interlaboratory comparison scheme in which National Institute of Metrology, China,
National Metrological Institute of Japan and Korea Research Institute of Standards and Science participated. The agreement
of the comparison results proved that the certification procedure of the CRMs is valid and that the certified values of Cd,
Cr, Hg and Pb are accurate and reliable. 相似文献
3.
I. Šperlingová L. Dabrowská V. Stránský J. Kuˇcera M. Tichý 《Accreditation and quality assurance》2003,8(3-4):113-116
A preliminary batch of the reference material was prepared by freeze-drying pooled urine samples obtained from healthy persons
occupationally exposed to styrene. Tests for homogeneity and stability were performed by determining urine concentrations
of mandelic (MA) and phenylglyoxylic acids (PGA). The urinary MA and PGA concentrations were followed over an 8-month period
using high performance liquid chromatography (HPLC). No changes of the concentration values were found. Pure PA and PGA from
Merck and Fluka, respectively, were used for traceability purposes, because certified or standard reference materials for
MA and PGA do not exist. Control material ClinChek-Urine Control (Recipe) was analysed simultaneously. The mean values of
MA and PGA compared well with the means of control samples and fell within the control range. The certified values and their
uncertainties were evaluated from the results of interlaboratory comparisons, homogeneity (277.0 ± 7.4 mg L−1 for MA and 148.0 ± 4.7 mg L−1 for FGA) and stability tests. The values are unweighted arithmetical averages of accepted results and their uncertainties
are combined uncertainties enlarged by coefficient k=1, evaluated from the standard uncertainties of the interlaboratory comparison, homogeneity and stability tests.
Received: 17 September 2002 Accepted: 1 November 2002
Acknowledgement This work was supported by the Internal Grant Agency of Ministry of Health of the Czech Republic (Grant NJ/6784–3).
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to I. Šperlingová 相似文献
4.
Lei Zhang Ting Huang Xueyan Liu Min Zhang Kai Li 《Journal of Analytical Chemistry》2011,66(4):368-372
A novel sorbent, nano-Al2O3 was employed for the separation and preconcentration of thallium from aqueous solution in batch equilibrium experiments.
It was found that the adsorption percentage of thallium ions was close to 100% at pH 4.5, and the desorption by 1.0 mL of
0.25 M HCl reached 99%. The adsorption equilibrium was well described by the Langmuir isotherm model with maximum adsorption
capacity of 5.78 mg/g (20 ± 0.1°C). The enrichment factor values of Tl(III) was 25 for 25 mL sample. Detection limit of thallium
(3σ, n = 11) equal to 0.8 μg/mL and relative standard deviation (2.4%) were obtained. The method has been successfully applied to
the determination of trace thallium in some environmental samples and the certified reference material polymetallic nodule
(GBW07296) with satisfactory results. 相似文献
5.
Results of a thorough study and application of flow injection atomic absorption spectrometry for the determination of As,
Pb and Hg in parts per million to sub-parts per billion levels in environmental and biological samples have been described.
Various standard reference materials from the National Bureau of Standards, USA, the National Institute of Standards and Technology,
USA, the Community Bureau of Reference, Brussels, Belgium and the National Institute for Environmental Studies, Japan and
Standard Chinese river sediment were used. By flow injection hydride generation AAS the standard reference materials were
analyzed for As and Pb. Mercury was determined by cold vapour flow injection AAS from environmental and biological standard
reference materials. The technique is fast, simple and highly sensitive. It takes only 30 s for each analysis from the digested
solution. The detection limits of As, Pb and Hg are 1.8 μg L–1 and 2.0 μg L–1 and 1.5 μg L–1, respectively. The results show good agreement with the certified values.
Received: 9 May 1996 / Revised: 13 August 1996 / Accepted: 14 August 1996 相似文献
6.
Laser ablation inductively coupled plasma isotope dilution mass spectrometry (LA–ICP–IDMS) was applied to the direct and simultaneous
determination of the platinum group elements (PGEs) Pt, Pd, Ru, and Ir in geological and environmental samples. A special
laser ablation system with high ablation rates was used, along with sector field ICP–MS. Special attention was paid to deriving
the distributions of PGEs in the pulverized samples. IDMS could not be applied to the (mono-isotopic) Rh, but the similar
ablation behavior of Ru and Rh allowed Rh to be simultaneously determined via relative sensitivity coefficients. The laser
ablation process produces hardly any oxide ions (which usually cause interference in PGE analysis with liquid sample injection),
so the ICP–MS can be run in its low mass resolution but high-sensitivity mode. The detection limits obtained for the geological
samples were 0.16 ng g−1, 0.14 ng g−1, 0.08 ng g−1, 0.01 ng g−1 and 0.06 ng g−1 for Ru, Rh, Pd, Ir and Pt, respectively. LA–ICP–IDMS was applied to different geological reference materials (TDB-1, WGB-1,
UMT-1, WMG-1, SARM-7) and the road dust reference material BCR-723, which are only certified for some of the PGEs. Comparisons
with certified values as well as with indicative values from the literature demonstrated the validity of the LA–ICP–IDMS method.
The PGE concentrations in subsamples of the road dust reference material correspond to a normal distribution, whereas the
distributions in the geological reference materials TDB-1, WGB-1, UMT-1, WMG-1, and SARM-7 are more complex. For example,
in the case of Ru, a logarithmic normal distribution best fits the analyzed concentrations in TDB-1 subsamples, whereas a
pronounced nugget effect was found for Pt in most geological samples. 相似文献
7.
Femtosecond laser ablation inductively coupled plasma mass spectrometry was used for the quantification of 23 metallurgical
relevant elements in unalloyed, alloyed and highly alloyed steels, and super alloys. It was shown that by using scanning mode
ablation with large ablation spot diameters (250 μm), stable and representative sampling can be achieved for the majority
of elements, except for bismuth and lead. For Bi and Pb up to 46%, temporal relative standard deviation (TRSD) was encountered,
whereas for most other elements, the TRSDs were below 10%. Calibration with matrix-matched and non-matrix-matched standards
provided similar agreement within the uncertainty of the certified values. However, the non-matrix-matched standard-based
quantification was more influenced by interferences rather than ablation- or excitation-related matrix effects. The method
was validated using 34 certified reference materials. 52Cr, 51V, or 55Mn were used as internal standards due to the fact that the Fe concentration was not certified for the majority of reference
materials. The determined concentrations for major and minor elements indicate that the total matrix internal standardization
(100 wt.%) is applicable, which requires no knowledge about the steel samples prior to analysis. 相似文献
8.
An accurate and sensitive multi-species species-specific isotope dilution GC–ICP–MS method was developed for the simultaneous
determination of trimethyllead (Me3Pb+), monomethylmercury (MeHg+) and the three butyltin species Bu3Sn+, Bu2Sn2+, and BuSn3+ in biological samples. The method was validated by three biological reference materials (CRM 477, mussel tissue certified
for butyltins; CRM 463, tuna fish certified for MeHg+; DORM 2, dogfish muscle certified for MeHg+). Under certain conditions, and with minor modifications of the sample pretreatment procedure, this method could also be
transferred to environmental samples such as sediments, as demonstrated by analyzing sediment reference material BCR 646 (freshwater
sediment, certified for butyltins). The detection limits of the multi-species GC–ICP–IDMS method for biological samples were
1.4 ng g−1 for MeHg+, 0.06 ng g−1 for Me3Pb+, 0.3 ng g−1 for BuSn3+ and Bu3Sn+, and 1.2 ng g−1 for Bu2Sn2+. Because of the high relevance of these heavy metal alkyl species to the quality assurance of seafood, the method was also
applied to corresponding samples purchased from a supermarket. The methylated lead fraction in these samples, correlated to
total lead, varied over a broad range (from 0.01% to 7.6%). On the other hand, the MeHg+ fraction was much higher, normally in the range of 80–100%. Considering that we may expect tighter legislative limitations
on MeHg+ levels in seafood in the future, we found the highest methylmercury contents (up to 10.6 μg g−1) in two shark samples, an animal which is at the end of the marine food chain, whereas MeHg+ contents of less than 0.2 μg g−1 were found in most other seafood samples; these results correlate with the idea that MeHg+ is usually of biological origin in the marine environment. The concentration of butyltins and the fraction of the total
tin content that is from butyltins strongly depend on possible contamination, due to the exclusively anthropogenic character
of these compounds. A broad variation in the butylated tin fraction (in the range of <0.3–49%) was therefore observed in different
seafood samples. Corresponding isotope-labeled spike compounds (except for trimethyllead) are commercially available for all
of these compounds, and since these can be used in the multi-species species-specific GC-ICP-IDMS method developed here, this
technique shows great potential for routine analysis in the future. 相似文献
9.
The mass fractions of six organochlorine pesticides in a fish oil certified reference material (CRM) have been determined
using multiple methods of analysis. Fish oil was extracted from the filet of Tilapia fish collected from the River Nile, and
this CRM was recently issued by the National Institute of Standards (NIS). It can be used as natural matrix CRM for organochlorine
pesticides determination in fish and for marine environmental measurement purposes. The analytical methods used are described,
and the obtained results were combined to calculate the mass fractions of the six detected organochlorine pesticides and their
associated uncertainty values. It has been concluded that mass fractions of four pesticides are certified values. These are
1,1-(dichloroethylidene)bis[4-chlorobenzene](4,4′-DDE), 1,1-(2,2,-dichloroethylidene)bis[4-chlorobenzene] (4,4′-DDD), 1-chloro-2-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene
(2,4′-DDT) and 1,1-(2,2,2-trichloroethylidene)bis[4-chlorobenzene] (4,4′-DDT). Meanwhile, mass fractions of two pesticides
were reference values. These are heptachlor and 1-chloro-2-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene (2,4′-DDD). 相似文献
10.
The concentration of99Tc in IAEA reference materials has been determined with an ICP-MS as 0.86±0.07 Bq·kg−1 dry for IAEA-373 (grass) and 0.25±0.02 Bq·kg−1 dry for IAEA-375 (soil). These being sufficiently higher than the detection limits of typical measurement methods, both materials
can be used as reference materials for determining low-level99Tc in environmental samples. 相似文献
11.
L. Harju Jan-Olof Lill Kjell-Erik Saarela Sven-Johan Heselius Fredrik Joachim Hernberg Alf Lindroos 《Fresenius' Journal of Analytical Chemistry》1997,358(4):523-528
Thick-target Particle Induced X-ray Emission (TTPIXE) was used for the quantitative determination of trace-element concentrations
in trunk wood. The wood samples were preconcentrated by dry ashing to improve the reliability of the sampling and the sensitivity
of the analytical method. Samples of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) were collected from a polluted area (Harjavalta) as well as from a relatively nonpolluted area (Merimasku) in southwestern
Finland. The elements studied were P, S, K, Ca, Mn, Fe, Ni, Cu, Pb, Rb, Sr, Ba, Cd and Ag. TTPIXE combined with dry ashing
is a sensitive and reliable analytical technique for most elements studied. The method was validified by using several certified
reference materials and also by ICP-MS analysis. Due to the low ash content (0.2–0.4%) in wood a high preconcentration factor
can be obtained. Differences in trace-element uptake were observed between the two tree species studied. Trunk wood from the
polluted area contained higher concentrations of heavy metal ions.
Received: 30 August 1996 / Revised: 11 October 1996 / Accepted: 3 November 1996 相似文献
12.
Slurry sampling electrothermal vaporization dynamic reaction cell inductively coupled plasma mass spectrometry (ETV-DRC-ICP-MS)
has been applied to determine Fe, Co, Ni, Cu, and Zn in biological samples. The influences of instrument operating conditions
and slurry preparation on the ion signals were reported. Pd was used as the modifier. The effectiveness of the ETV sample
introduction technique and dynamic reaction cell in alleviating various spectral interferences in ICP-MS analysis has been
demonstrated. This method has been applied to determine Fe, Co, Ni, Cu, and Zn in NIST SRM 1573a tomato leaves reference material
and NRCC DORM-2 dogfish muscle reference material and also real samples such as a tea and a swordfish sample purchased locally.
Since the sensitivities of the elements studied in slurry and aqueous solution were different, an analyte addition technique
was used for the determinations. The analytical results of the reference materials agreed with the certified values. The precision
between sample replicates was better than 6% for all determinations. The method detection limit estimated from analyte addition
curves was 0.01, 0.006, 0.007, 0.004, and 0.006 μg g−1 for Fe, Co, Ni, Cu, and Zn, respectively, in the original biological samples. 相似文献
13.
L. Harju Jan-Olof Lill Kjell-Erik Saarela Sven-Johan Heselius Fredrik Joachim Hernberg Alf Lindroos 《Analytical and bioanalytical chemistry》1997,358(4):523-528
Thick-target Particle Induced X-ray Emission (TTPIXE) was used for the quantitative determination of trace-element concentrations
in trunk wood. The wood samples were preconcentrated by dry ashing to improve the reliability of the sampling and the sensitivity
of the analytical method. Samples of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) were collected from a polluted area (Harjavalta) as well as from a relatively nonpolluted area (Merimasku) in southwestern
Finland. The elements studied were P, S, K, Ca, Mn, Fe, Ni, Cu, Pb, Rb, Sr, Ba, Cd and Ag. TTPIXE combined with dry ashing
is a sensitive and reliable analytical technique for most elements studied. The method was validified by using several certified
reference materials and also by ICP-MS analysis. Due to the low ash content (0.2–0.4%) in wood a high preconcentration factor
can be obtained. Differences in trace-element uptake were observed between the two tree species studied. Trunk wood from the
polluted area contained higher concentrations of heavy metal ions.
Received: 30 August 1996 / Revised: 11 October 1996 / Accepted: 3 November 1996 相似文献
14.
Brandão GP de Campos RC de Castro EV de Jesus HC 《Analytical and bioanalytical chemistry》2006,386(7-8):2249-2253
A procedure for the direct GFAAS determination of Ni in petroleum samples using a solid sampling strategy is proposed. Palladium
was used as conventional modifier. Central composite design multivariate optimization defined the optimum temperature program
and the Pd mass, allowing calibration using aqueous analytical solution. The limit of detection (LOD) at the optimized conditions
was 0.23 ng of Ni, for typical sample masses between of 0.10 and 0.60 mg. Linearity at least up to 11 ng of Ni and a characteristic
mass of 45 pg were observed, defining a dynamic range between 0.52 and 110 μg g−1. Typical coefficients of variation (n = 10) in the analysis of oil reference materials were 7%. Method validation was performed both by the analysis of oil certified
reference materials and by comparison with an independent method (ASTM 5863-B). No statistically significant difference was
observed between obtained and expected values. The total determination cycle lasted 5 min, equivalent to a sample throughput
of 6 h−1 for duplicate determinations. 相似文献
15.
Domínguez-Lledó FC Galindo-Riaño MD Díaz-López IC García-Vargas M Granado-Castro MD 《Analytical and bioanalytical chemistry》2007,389(2):653-659
In this work, a bulk liquid membrane method has been applied for Ni enrichment and separation from natural waters. The carrier-mediated
transport was accomplished by pyridine-2-acetaldehyde benzoylhydrazone dissolved in toluene as a complexing agent. The preconcentration
was achieved through pH control of source and receiving solutions via a counterflow of protons. The main variables were optimized
by using a modified simplex technique. High transport efficiencies (101.2 ± 1.8–99.7 ± 4.2%) were provided by the carrier
for nickel ions in a receiving phase of 0.31 mol L−1 nitric acid after 9–13 h depending on sample salinity. The precision of the method was 2.05% (without a saline matrix) and
4.04% (with 40 g L−1 NaCl) at the 95% confidence level and the detection limit of the blank was 0.015 μg L−1 Ni for detection by atomic absorption spectroscopy. The applicability of the method was tested on certified reference and
real water samples with successful results, even for saline samples. The relative errors were −0.60% for certified reference
materials and ranged from −0.39 to 2.90% and from 0.3 to 11.05% for real samples, obtained by comparison of inductively coupled
plasma mass spectrometry and adsorptive cathodic stripping voltammetry measurements, respectively. 相似文献
16.
A simple dissolution procedure is decribed for sediments to be analyzed for thallium by Laser-Excited Atomic Fluorescence
Spectrometry (LEAFS). It simply uses a nitric – hydrofluoric acid mixture at room temperature (a “cold dissolution” procedure
as opposed to the hot acid digestion) followed by a dilution with water (as opposed to the tedious steps of separation and
preconcentration). Excellent accuracy (91–106% recoveries) and precision (4–10% relative standard deviation) were demonstrated
by the use of five sediment reference materials of diverse origins. The detection limit was estimated to be 0.5 ng/g of thallium.
Additionally, a hot plate digestion procedure, using an in-house designed semi-enclosed Teflon beaker, was also investigated;
its analytical results agreed with certified values and confirmed the adequacy of the cold dissolution technique. The method
is being applied to study the sediment – water interactions in lake environments.
Received: 30 December 1996 / Revised: 20 March 1997 / Accepted: 30 March 1997 相似文献
17.
Xiangbing Zhu Dong Yang Xijun Chang Yuemei Cui Zheng Hu Xiaojun Zou 《Mikrochimica acta》2008,161(1-2):115-122
A new method using acetylsalicylic acid (aspirin) modified SiO2 nanoparticles (nanometer SiO2-aspirin) as a solid-phase extractant (SPE) has been developed for the preconcentration of trace amounts of Fe(III) prior
to their determination by inductively coupled plasma optical emission spectrometry. The preconcentration conditions of analytes
were investigated, including the pH value, the shaking time, the mass of sorbent, the sample flow rate and volume, the elution
condition and the interfering ions. At pH 4, the sorption capacity of nanometer SiO2-aspirin was found to be 1.28 mmol g−1. The preconcentration factor is 50. The detection limit (3σ) for Fe(III) was 0.49 ng mL−1. The method was validated by analyzing two certified reference materials (GBW 08301, river sediment and GBW 08303, polluted
farming soil), and the results obtained are in good agreement with standard values. The method was also applied to the determination
of trace Fe(III) in biological and water samples with satisfactory results.
Correspondence: Xiangbing Zhu, Department of Chemistry, Lanzhou University, Lanzhou 730000, P.R. China 相似文献
18.
Samuel Melaku Ilse Gelaude Frank Vanhaecke Luc Moens Richard Dams 《Mikrochimica acta》2003,142(1-2):7-12
Microwave digestion reduction-aeration and pyrolysis combined with cold vapour atomic absorption and cold vapour atomic fluorescence
are compared for the determination of total mercury in several biological and environmental matrices. The biological samples
were digested in a mixture of HNO3/H2O2, the environmental samples in a mixture of HNO3/HClO4. After reduction with SnCl2, the mercury was collected by two-stage gold amalgamation. After microwave digestion reduction-aeration, detection limits
of 1.4 ng g−1 and 0.6 ng g−1 were obtained for cold vapour atomic absorption spectrometry (CVAAS) and cold vapour atomic fluorescence spectrometry (CVAFS),
respectively, for 250 mg of environmental samples. For biological samples (500 mg) the detection limits were 0.7 ng g−1 (CVAAS) and 0.4 ng g−1 (CVAFS). After pyrolysis, detection limits of 3.5 ng g−1 and 1.6 ng g−1 for CVAAS and CVAFS, respectively, were obtained for a 10 mg sample. Pyrolysis can only be applied when the organic content
of the sample is not too high. Accurate results were obtained for 8 certified reference materials of both environmental and
biological origin. In addition, a real sludge sample was analysed.
Author for correspondence. E-mail: richard.dams@rug.ac.be
Received September 18, 2002; accepted December 3, 2002
Published online May 5, 2003 相似文献
19.
Jibrin Sabo Suleiman Bin Hu Xuli Pu Chaozhang Huang Zucheng Jiang 《Mikrochimica acta》2007,159(3-4):379-385
A new method is proposed using a microcolumn (20 mm × 2.0 mm) packed with nanometer-sized zirconia as solid-phase extractor
for the separation/preconcentration of Mn, Cu, Cr, Zn, Ni and Co prior to their determination by inductively coupled plasma
optical emission spectrometer (ICP-OES) in environmental samples. The factors affecting the separation and preconcentration
of analytes such as pH, sample flow rate and volume, eluent concentration and volume were determined, interfering ions were
studied, and the optimal experimental conditions were established. The adsorption capacity of nanometer-sized ZrO2 for Mn, Cu, Cr, Zn, Ni and Co was found to be 1.3, 1.3, 1.7, 2.0, 3.9 and 1.5 mg g−1, respectively. The detection limits of the method were 12, 58, 24, 2, 7 and 36 ng L−1, respectively, with a preconcentration factor of 25. The precision of this method was 1.7% (Mn), 2.9% (Cu), 5.9% (Mn), 3.8%
(Mn), 6.2% (Mn) and 4.3% (Mn) with 9 determinations of 10 ng mL−1 of target analytes, respectively. The method was successfully applied to the determination of trace metals in lake water,
dried fish samples, certified reference materials of human hair and milk, and provided satisfactory results. 相似文献
20.
M. Žemberyová R. Jankovič I. Hagarová H.-M. Kuss 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007
A modified three-step sequential extraction procedure proposed by the Commission of European Communities Bureau of Reference (BCR) was applied to certified reference materials of three different soil groups (rendzina, luvisol, cambisol) and sewage sludge of different composition originating from a municipal water treatment plant in order to assess potential mobility and the distribution of vanadium in the resulting fractions. Analysis of the extracts was carried out by electrothermal atomic absorption spectrometry with Zeeman background correction using transversely heated graphite atomizers. Extracts showed significant matrix interferences which were overcome by the standard addition technique. The original soil and sludge certified reference materials (CRMs) and the extraction residue from the sequential extraction were decomposed by a mixture of HNO3–HClO4–HF in an open system. The content of V determined after decomposition of the samples was in very good agreement with the certified total values. The accuracy of the sequential extraction procedure was checked by comparing the sum of the vanadium contents in the three fractions and in the extraction residue with the certified total content of V. The amounts of vanadium leached were in good correlation with the certified total contents of V in the CRMs of soils and sewage sludge. In the soils examined, vanadium was present almost entirely in the mineral lattice, while in the sewage sludge samples 9–14% was found in the oxidizable and almost 25% in the reducible fractions. The recovery ranged from 93–106% and the precision (RSD) was below 10%. 相似文献