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1.
Annibaldi A Truzzi C Illuminati S Bassotti E Scarponi G 《Analytical and bioanalytical chemistry》2007,387(3):977-998
Eight PM10 aerosol samples were collected in the vicinity of the “Mario Zucchelli” Italian Antarctic Station (formerly Terra
Nova Bay Station) during the 2000–2001 austral summer using a high-volume sampler and precleaned cellulose filters. The aerosol
mass was determined by differential weighing of filters carried out in a clean chemistry laboratory under controlled temperature
and humidity. A two-step sequential extraction procedure was used to separate the water-soluble and the insoluble (dilute-HCl-extractable)
fractions. Cd, Pb and Cu were determined in the two fractions using an ultrasensitive square wave anodic stripping voltammetric
(SWASV) procedure set up for and applied to aerosol samples for the first time. Total extractable metals showed maxima at
midsummer for Cd and Pb and a less clear trend for Cu. In particular, particulate metal concentrations ranged as follows:
Cd 0.84–9.2 μg g−1 (average 4.7 μg g−1), Pb 13.2–81 μg g−1 (average 33 μg g−1), Cu 126–628 μg g−1 (average 378 μg g−1). In terms of atmospheric concentration, the values were: Cd 0.55–6.3 pg m−3 (average 3.4 pg m−3), Pb 8.7–48 pg m−3 (average 24 pg m−3), Cu 75–365 pg m−3 (average 266 pg m−3). At the beginning of the season the three metals appear widely distributed in the insoluble (HCl-extractable) fraction (higher
proportions for Cd and Pb, 90–100%, and lower for Cu, 70–90%) with maxima in the second half of December. The soluble fraction
then increases, and at the end of the season Cd and Pb are approximately equidistributed between the two fractions, while
for Cu the soluble fraction reaches its maximum level of 36%. Practically negligible contributions are estimated for crustal
and sea-spray sources. Low but significant volcanic contributions are estimated for Cd and Pb (∼10% and ∼5%, respectively),
while there is an evident although not quantified marine biogenic source, at least for Cd. The estimated natural contributions
(possibly including the marine biogenic source) cannot account for the high fractions of the metal contents, particularly
for Pb and Cu, and this suggests that pollution from long-range transport is the dominant source.
Figure Aerosol sampling in Antarctica 相似文献
2.
Karadjova IB Lampugnani L D'Ulivo A Onor M Tsalev DL 《Analytical and bioanalytical chemistry》2007,388(4):801-807
A rapid, accurate, and precise method is described for the determination of Pb in wine using continuous-flow hydride generation
atomic fluorescence spectrometry (CF-HGAFS). Sample pretreatment consists of ten-fold dilution of wine followed by direct
plumbane generation in the presence of 0.1 mol L−1 HCl and 1% m/v K3[Fe(CN)6] with 1% m/v NaBH4 as reducing agent. An aqueous standard calibration curve is recommended for Pb quantification in wine sample. The method
provides a limit of detection and a limit of quantification of 0.3 μg L−1 and 1 μg L−1, respectively. The relative standard deviation varies between 2–6% (within-run) and 4–11% (between-run) at 3–30 μg L−1 Pb levels in wine. Good agreement has been demonstrated between results obtained by CF-HGAFS and direct electrothermal atomic
absorption spectrometry in analyses of red and white wines within the concentration range of 9.2–25.8 μg L−1 Pb. 相似文献
3.
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
4.
Summary A reversed-phase ion-pair chromatographic (RPIPC) method withN,N,N′, N′-ethylenediaminetetrakis(methylenephosphonic acid) (EDTMP) as coordinating agent has been developed for simultaneous separation
and detection of Cu(II), Fe(III), and Pb(II) ions. Response is linearly dependent on amount of sample over the range 9.52–50.8
μg mL−1 for Cu(II), 8.31–41.8 μg mL−1 for Fe(III), and 37.3–51.8 μg mL−1 for Pb(II). The method has been applied successfully to an artificial mixed-ore sample. 相似文献
5.
C. Pohl 《Accreditation and quality assurance》1997,2(1):2-10
The aim of this intercomparison exercise was to assess the comparability of trace metal analyses of blank filters and of
marine suspended particulate matter (SPM) on filters performed by laboratories in ICES member countries. Fifteen experts from
the United Kingdom, Canada, France, Germany, the Netherlands, Norway, Poland, Russia, and the United States were invited to
participate in this exercise for trace metal analyses of Cu, Pb, Zn, Cd, Al, Li, Fe, Mn, Ni and Co (tentative) in SPM. Each
filter analysed in this project was an individual sample, the absolute loadings on the filters varying from 0.8 to 2 mg of
SPM. The inter-laboratory means and the relative standard deviations (RSD) from the grand mean for the metals determined were:
Al 67.5 mg/g, 8.3%, Fe 51.7 mg/g, 10.9%, Cd 1.5 μg/g, 22.7%, Cu 39 μg/g, 13.3%, Pb 38 μg/g, 34.7%, Mn 1060 μg/g, 13%, Ni 49.2
μg/g, 29%, Zn 182 μg/g, 32.5%, Li 52.8 μg/g, 26.1%, Co 15.4 μg/g, 23.6%. In general, the exercise demonstrated that it is
possible for the various participants to collect very small amounts of SPM and analyse it by the different determination techniques.
Compared to earlier exercises, comparability between laboratories was still difficult to achieve and limited.
Received: 27 June 1996 Accepted: 15 August 1996 相似文献
6.
Dula Amarasiriwardena Kamal Sharma R. M. Barnes 《Fresenius' Journal of Analytical Chemistry》1998,362(5):493-497
The presence of lead as a contaminant in calcium supplements has aroused considerable public health interest in recent years.
In this investigation lead and lead isotope ratios were determined by ICP-MS in ten brands of calcium supplements after high
pressure/temperature digestion. Calcium supplements (200 to 250 mg) were digested in 2 mL of nitric acid at 230 °C and at
a pressure of 1770 psi (1.2 × 104 kPa). Lead concentrations were determined by matrix-matched lead standards prepared in a high-purity calcium carbonate matrix.
Good recoveries of lead and calcium were obtained for certified animal bone reference material. High levels of Pb (8 to 28
μg Pb per g of calcium) were found in calcium supplements that contain dolomite or bone meal. Chelated and refined calcium
supplements had lower Pb levels (0.8 to 0.9 μg Pb/g Ca). Application of lead isotope ratios to distinguish the origin of calcium
sources was also explored.
Received: 9 June 1998 / Revised: 20 July 1998 / Accepted: 25 July 1998 相似文献
7.
Miguel Angel Salas-Luevano Eduardo Manzanares-Acuña Consuelo Letechipia-de Leon Víctor Martin Hernandez-Davila Hector Rene Vega-Carrillo 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(1):35-39
Lead concentration in soils has been measured in Vetagrande, an old mining town located at the state of Zacatecas in México.
Eighty nine soils samples were analyzed using Energy Dispersive X-ray Fluorescence. The lead concentrations were treated with
the Kriging method in order to estimate the lead concentration distribution in the studied area. Pb levels in soils were from
8 to 7730 μg kg−1, where 28.1% of soil samples have less than 400 μg kg−1, 71.9% is above 400 μg kg−1 which is the maximum level recommended by the EPA for residential use of soil. Lead concentration measured around public
sites represent a risk of lead intake in the population. 相似文献
8.
Summary Formaldehyde, as its dimedone adduct formaldemethone, has been detected and quantified in all the tested species of angiosperms,
gymnosperms, pteridophytes, lichens and fungi, as well as in the two species tested of cyanobacteria and the one species of
charophyte. Yields ranged from<10μg g−1 to 6940 μg g−1 fresh weight, calculated as formaldemethone (equivalent to <1 μg g−1 to 713 μg g−1 fresh weight, calculated as formaldehyde). An HPLC procedure was used for quantification of formaldemethone. A linear relationship
was found between 20 and 2160 μg g−1 and the statistical limit of detection was calculated as 48 μg g−1. 相似文献
9.
A new and efficient Hg(II) back-elution method for the desorption of Cd, Cu, and Pb from Chelex-100 chelating resin was developed.
A smaller eluent volume and shorter elution time can be achieved using an Hg(II) containing eluent rather than pure nitric
acid. Owing to the remaining Hg(II) ion in the effluent, a mercury thin-film electrode is formed in-situ during the anodic
stripping voltammetric determination without any further addition of Hg(II). The results indicate that all the analytes in
seawater matrix can be completely adsorbed on Chelex-100 resin from the sample at pH 6.5, and subsequently eluted from the
resin with an acid solution of 5 × 10–4 mol/L Hg2+ + 1 mol/L HClO4. The detection limits obtained from the differential-pulse anodic (μg L–1 to ng L–1) stripping voltammetry are at sub-ppb to ppt (μg L–1 to ng L–1) levels permitting to determine Cd, Cu and Pb traces in seawater. The analytical reliability was confirmed by the analysis
of the certified reference material CASS-II (open ocean seawater).
Received: 22 April 1997 / Revised: 5 August 1997 / Accepted: 7 August 1997 相似文献
10.
Lei Zhang Liang Xu Xiao-Jie Tan Qiong-Feng Liao Wei Guo Xiao-Hui Chen Kai-Shun Bi 《Chromatographia》2007,66(1-2):115-120
A sensitive and reliable ion-paired high-performance liquid chromatographic method has been established for the simultaneous
quantification of six major active ingredients, namely baicalin, baicalein, wogonin, oxysophocarpine, oxymatrine and matrine
in the Chinese herbal preparation, Sanwu-Huangqin-Tang. HPLC analyses were performed on a Phenomenex luna C18 column with mobile phase of methanol–acetonitrile–aqueous phosphoric acid at a flow rate of 0.9 mL min−1. The complete separation was achieved within 35 min for the six target constituents. A good linear regression relationship
between peak-areas and concentrations was obtained over the range of 12.10–242.0 μg*mL−1 for baicalin, 5.05–101.0 μg*mL−1 for baicalein, 0.95–19.0 μg*mL−1 for wogonin, 2.75–55.0 μg*mL−1 for oxysophocarpin, 2.75–55.0 μg*mL−1 for oxymatrine and 4.90–98.0 μg*mL−1 for matrine, respectively. The repeatability was evaluated by intra- and inter-day assays with relative standard deviation
(RSD) being less than 5.1%. The recoveries, measured at three concentration levels, varied from 93.8 to 102.1%. The assay
was successfully applied for determination of six bioactive compounds in Sanwu-Huangqin-Tang. The interaction of chemical
constituents was observed when the herbs were used in compatibility. The results indicated that the developed assay method
was rapid, accurate and could be readily utilized as a quality control method for Sanwu-Huangqin-Tang. 相似文献
11.
The medium energy intense neutrons (MEIN) available at the Brookhaven Chemistry Linac Irradiation Facility have an energy
distribution up to ∼160 MeV an effective neutron flux of ∼1.3×1011 cm−2s−1. The present work explores the feasibility of using this facility for the analysis of Tl, Pb and Bi by activation with MEIN.
The most sensitive reactions, from a practical standpoint, were found to be Tl (n, xn)200Tl (x=4, 6), Pb (n, xn)204mPb (x=0, 3, 4. 5) and209Bi (n, 6n)204Bi. The absolute sensitivities attainable with these reactions are 0.1, 0.05 and 0.08 μg of Tl, Pb and Bi respectively, for
1 h irradiation at 1.3×1011 n cm−2s−1 with samples counted 2 h after the end of irradiation. The advantages of the method over thermal neutron activation analysis
are that all three elements can be assayed at the sub-microgram concentration levels by γ-spectrometry with the help of a
simple radiochemical purification and the analytical results can be verified by cross checking via the multiple (n, xn) reaction
products. However, interference from Bi in the determination of Pb and from Pb and Bi in the determination of Tl limits its
usefulness to the analysis of Bi.
This research was sponsored under contract with the United States Department of Energy supported by its Office of Basic Energy
Sciences (support for H.L. FINSTON is under Contract no. DE-AC02-76-ER03126). 相似文献
12.
H. A. Das F. A. Hartog F. A. De Witte 《Journal of Radioanalytical and Nuclear Chemistry》1973,14(2):375-385
The determination of traces of beryllium in large samples by the (γ, n) reaction, using a124Sb gamma-source, is in general hampered by the rather high handling costs when a BF3 counter is used for the neutron detection. When manganese dioxide is used as an activation detector, the analysis is possible
with a simple facility which can be stored in a water basin. The lower limit of the determination is ∼ 1 μg/g for a sample
weight of 50 g. 相似文献
13.
dos Santos EJ Herrmann AB Frescura VL Welz B Curtius AJ 《Analytical and bioanalytical chemistry》2007,388(4):863-868
Among the “traditional” hydride-forming elements, lead is probably the most difficult, and its determination in this form
has rarely been reported in the literature. In this paper a simple and rapid method, axial-view inductively-coupled plasma
optical-emission spectrometry using on-line hydride generation (HG–ICP–OES) from samples prepared as slurry, is proposed for
determination of lead in environmental samples. The samples (20–50 mg, particle size ≤120 μm) were treated with 1 mL aqua
regia in a 40-kHz ultrasonic bath for 60 min. The slurry was diluted to a final volume of 50 mL with a 10% m/v solution of (NH4)2S2O8. The concentrations of NaBH4, tartaric acid, and (NH4)2S2O8, used for on-line plumbane generation were optimized by means of a complete factorial analysis applied to an aqueous standard
solution and to the slurry of a sediment certified reference material (CRM). External calibration against aqueous standards
in the concentration range 10–100 μg L−1 was used for analysis of six CRM—three marine sediments, one river sediment, and two sewage sludges. Analysis of the filtered
slurry showed that Pb was only partially extracted into the liquid phase. Several major concomitants tested did not affect
the Pb signal. The detection limit (3s, n = 10) for 20 mg sample in a final volume of 50 mL was 5.0 μg g−1. Tin was the only other hydride-forming analyte that could be determined satisfactorily with Pb; for tin the detection limit
was 1.0 μg g−1. The values obtained for Pb and Sn were not significantly different from the certified concentrations, according to the t-test at the 95% confidence level. Nine river sediments collected locally were also analyzed and the concentrations were in
agreement with results obtained after total digestion. 相似文献
14.
The non-destructive determination of lithium was performed by using a Cerenkov counter for the detection of the 13 MeV (max)
β-particles from the 0.84 sec8Li produced by the reaction7Li(n,γ)8Li. Under optimal conditions for a favorable signal-to-noise ratio, a count rate of about 35 cps/μg lithium at the beginning
of the measurement was obtained, with a background of 4.5 cps and a working range of 3–400 μg lithium. The interference of
other elements was studied. Several lithium-containing minerals and a sample of Dead Sea water were analyzed. The isotopic
composition of lithium in aqueous solutions was determined by the simultaneous measurement of the neutrons produced by the
reactions6Li(n,α)t and18O(t,α)17N, and the β-particles emitted by8Li. 相似文献
15.
Solid-phase extraction (SPE) method for preconcentration and determination of Cd(II), Pb(II), Co(II), Ni(II), and Cu(II) aqueous
samples by inductively coupled plasma optical emission spectrometry is described. The preconcentration of analytes is accomplished
by retention of their chelates with 1.10-phenanthroline in aqueous solution on a solid phase containing carboxylic acid (COOH)
bonded to silica gel in a column. The limits of detection values (defined as “3s” where “s” is standard deviation of the blank
determination) are 3.6 μg/L for Cd(II), 17.5 μg/L for Pb(II), 3.1 μg/L for Co(II), 2.1 μg/L for Ni(II), and 4.4 μg/L for Cu(II)
and corresponding limit of quantification (6s) values are 7.2, 35, 6.2, 4.2 and 8.8 μg/L, respectively. As a result, a simple
method was elaborated for the group concentration and determination of the above mentioned metals in reference material and
in samples of plant material.
The article is published in the original. 相似文献
16.
A sensitive analytical method was established for the determination of Th and U in activated concrete samples. The method
combines an anion-exchange separation step with an ICP-MS determination technique. In the ICP-MS measurement, a few μg mL–1 of Al and Ca, a few ng mL–1 of Mn, La, Ce, Nd and Pb and pg mL–1 amounts of Li, Zr, Nb and Ba coexisting in the anion-exchange fraction of Th and U did not interfere. No adverse interference
effects were observed in real sample analyses. The obtained detection limits (3σ, n = 10) of Th and U were 2.3 and 1.8 pg mL–1, respectively. The analytical precisions for ca. 5 μg g–1 Th and ca. 1 μg g–1 U in real activated concrete samples were equally less than 7% RSD. The accuracies obtained by the analysis of GSJ rock standard
samples were –18.1 to 0.4% for the Th determination and –14.0 to –5.7% for the U determination. The method uses the conventional
absolute calibration curve. The internal standard calibration is unnecessary.
Received: 14 March 1999 / Revised: 13 July 1999 / Accepted: 15 July 1999 相似文献
17.
V. Jánošová M. Sýkorová O. Štroffeková E. Havránek 《Journal of Analytical Chemistry》2010,65(1):56-63
Preconcentration performance characteristics of precipitation of Mn, Fe, Co, Cu, Zn, Pb, Hg, and Cd and with subsequent filtration
through cellulose nitrate membrane were investigated for the X-ray spectrometry identification and determination of trace
metal ions in drug samples. The method was optimised for several parameters, including pH and amount of thioacetamide. The
investigated analyte ions were collected on cellulose nitrate membrane filter (Pragopor 4) as sulphides after the reaction
with thioacetamide. Optimal reaction conditions were found out (pH 8.5 for Fe, Zn, Hg, and Cd and pH 11.5 for Mn, Co, Cu,
and Pb; 1.2 mL of added thioacetamide). Thereafter, the content of these elements was determined in the samples of drugs—NaCl,
glucose and dextrane. The rapidity of this method, its polycomponent character and low detection limits (for filters: Mn—1.09
μg, Fe—1.08 μg, Co—0.82 μg, Cu—0.42 μg, Zn—0.61 μg, Pb—0.45 μg, Hg—0.42 μg, and Cd—0.99 μg) have proved this method to be
very promising in rapid screening used in quality control of drugs. 相似文献
18.
C. L. Branquinho V. J. Robinson 《Journal of Radioanalytical and Nuclear Chemistry》1975,24(2):321-326
A method is described for the use of212Pb to measure overall recovery in lead analyses. Other modifications of published procedures are also outlined. Most difficulties
occur with samples containing small amounts (<10 μg) of Pb. In addition to low recovery factors, spectra are often obscured
by the presence of dithizone oxidation product: a procedure for dealing with this is given. 相似文献
19.
A new method was developed for the simultaneous determination of lidocaine, proline and lomefloxacin in human urine by capillary
electrophoresis-electrochemiluminescence detection with Ru(bpy)3
2+. Conditions of the separation and detection were investigated and optimized. It was proved that 20 mM phosphate buffer at
pH 6.7 could achieve the most favorable resolution, and the high sensitivity of detection was obtained by using the detection
potential at 1.15 V and 5 mM Ru(bpy)3
2+–60 mM phosphate buffer at pH 7.6 in the detection reservoir. The detection limits were 0.02 μg mL−1 for lidocaine, 0.03 μg mL−1 for proline and 0.06 μg mL−1 for lomefloxacin. Relative standard deviations of the ECL intensity and the migration time were 3.5 and 1.1% for 6 μg mL−1 lidocaine, 3.2 and 1.0% for 6 μg mL−1 proline and 3.7 and 1.2% for 6 μg mL−1 lomefloxacin, respectively. A baseline separation for lidocaine, proline and lomefloxacin was achieved within 360 s. The
developed method was successfully applied to determine the amounts of lidocaine, proline and lomefloxacin in human urine.
The recovery and RSD were in the range of 93.3–97.2 and 3.8–4.9%, respectively. 相似文献
20.
The potential of modified multiwalled carbon nanotubes (a solid-phase extraction sorbent), for the simultaneous separation
and preconcentration of lead, cadmium and nickel; has been investigated. Lead, cadmium and nickel, were adsorbed quantitatively;
on modified multiwalled carbon nanotubes (in the pH range of 2–4). Parameters influencing, the simultaneous preconcentration
of Pb(II), Ni(II) and Cd(II) ions (such as pH of the sample, sample and eluent flow rate, type and volume of elution solution
and interfering ions), have been examined and optimized. Under the optimum experimental conditions, the detection limits of
this method. for Pb(II), Ni(II) and Cd(II) ions, were 0.32, 0.17 and 0.04 ng mL−1 in original solution, respectively. Seven replicate determinations, of a mixture of 2.0 μg mL−1 lead and nickel, and 1.0 μg mL−1 cadmium; gave a mean absorbance of 0.074, 0.151 and 0.310, with relative standard deviation 1.7%, 1.5% and 1.2%, respectively.
The method has been applied, to the determination of trace amounts of lead, cadmium and nickel; in biological and water samples,
with satisfactory results.
相似文献