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Fifty air filters with fine and coarse fractions were prepared from NIST 2710 contaminated soil. Eighteen pairs were made and sent to laboratories of the Coordinated Research Program (CRP) on Applied Research on Air Pollution Using Nuclear-Related Analytical Techniques for elemental determination. The results of this intercomparison are discussed in this paper.  相似文献   

3.
At ITN, PM10 and PM2.5 aerosols were collected on Nuclepore® polycarbonate filters of 47 mm diameter, using Gent samplers at 15–17 l/min air flux. Filters were analyzed by INAA and PIXE. The availability of certified filters was very scarce, viz.: (1) fly ash embedded in a methyl cellulose 47 mm foil 10 µm thick, BCR CRM128, (2) particle-size reduced air particulate matter (APM) to simulate PM2.5 aerosol matter deposited on a 47 mm polycarbonate filter membrane, NIST SRM 2783. The high price and scarcity of APM standards did not permit their frequent use for analytical quality control. At ITN, to control the filter results' accuracy, the chemical elements potassium, iron and zinc, determined by both techniques, were systematically compared. After a few improvements introduced in INAA, this technique was now considered at ITN as the reference technique in air particulate measurements. Comparison of INAA to PIXE was discussed. Compared to previously reported situation it was concluded that the results were in better agreement for iron and zinc, and potassium values were still biased to the same extent as before.  相似文献   

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A review is presented on the use of various activation analysis methods for the determination of trace elements in air particulate and related matters. A discussion is given on the contribution of such methods in solving the problem of air pollution in various parts of the world. This work is a part of a program undertaken by this Department for the evaluation of the various analytical techniques as investigative tools in pollution and other environmental studies.  相似文献   

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Müller J  Rohbock E 《Talanta》1980,27(8):673-675
A method for measuring polycyclic aromatic hydrocarbons (PAHs) in ambient air is described. The particulate matter is collected on fibre-glass filters. The loaded filters are placed in tetrahydrofuran and the PAHs dissolved with the aid of ultrasonics and analysed by high-performance liquid chromatography on a reversed-phase column with a methanol-water mixture as mobile phase. The PAHs are detected by use of a UV-detector and the 254-nm mercury emission line. The method is rapid and adequate for measuring about 15 PAH-components in ambient air.  相似文献   

8.
The Institute of Non-Ferrous Metals, Gliwice (Poland) has developed a process for uniform deposition of urban particulate matter on filter media which enables the production of reference materials for X-ray calibration by depositing certified reference materials on filters at different mass loadings. This process has been used to prepare the SRM 2783 for the National Institute of Standards and Technology, which consists of a set of five such filters based on the use of the SRM 1648 for the deposition.  相似文献   

9.
The present work deals with the optimization and validation of a method for the quantitative simultaneous ICP determination of metals in ambient air particulate matter. The attention has been focused on the thoracic fraction (PM10) and twelve different metals were chosen on the basis of their toxicity and of their possible use as chemical tracers. The microwave acidic digestion of the samples has been performed in the presence of different reagents and under different conditions and particular attention has been paid to the optimization of the whole analytical procedure and to the evaluation of accuracy and precision related to the single operative steps. The interferences due to the reagents and to the sampling supports have also been evaluated. In addition, the analytical procedure has been checked by examining the equivalence of results related to parallel sampled filters pairs.  相似文献   

10.
In the context of the general mandate of the European Union Community Reference Laboratory (CRL) for residues in living animals and their products established at the Istituto Superiore di Sanità, a pilot study was undertaken to assess the possibility of producing a new certified reference material (CRM) for trace elements in a matrix of honey. The elements considered were As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sn, V and Zn. Their determination was performed by inductively coupled plasma (ICP)-based techniques. Data obtained with different ICP techniques were generally in good agreement. In light of these results, the next step was the effective production of a candidate CRM in a honey matrix. In the preliminary phase, two different types of honey, i.e., Eucalyptus (solid and sticky) and Robinia (viscous and sticky), were pretreated at the Institute for Reference Materials and Measurements, Joint Research Centre, European Commission (EC-JRC-IRMM) in order to produce the materials candidate for the certification process. Approximately 600 ampoules were thus produced for the Robinia honey and 450 ampoules for the Eucalyptus honey, each ampoule containing 5 g of an aqueous solution of honey (with 20% and 30% high purity water, respectively) and sealed under inert gas (Ar). A ring test to determine the levels of the chemical elements and a long-term study to evaluate the stability of the samples is in progress. Tentative figures for the analytes of interest are (in ng g−1): Robinia, As, 1.28±0.09; Cd, 0.59±0.08; Cr, 2.36±0.21; Cu, 57.6±3.2; Fe, 209±9; Mn, 90.8±3; Ni, 18.1±0.6; Pb, 23±1.5; Sn, 8.10±0.35; V, 1.19±0.37; and Zn, 178±4; Eucalyptus, As, 3.18±0.21; Cd, 0.70±0.08; Cr, 2.73±0.22; Cu, 141±6; Fe, 926±16; Mn, 1905±81; Ni, 7.77±0.4; Pb, 138±4; Sn, 7.97±0.16; V, 3.47±0.15; and Zn, 405±9.  相似文献   

11.
NIST standard reference material SRM 2783 was employed to validate a high temperature, high pressure, two-stage microwave assisted acid digestion procedure using HNO3, HF and H3BO3 developed for the analysis of trace elements (including rare earths) in atmospheric fine particulate matter (PM2.5) prior to inductively coupled plasma mass spectrometry (ICP-MS). This method quantitatively solubilized Na, Mg, Al, K, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sb, Cd, Cs, Ba, Pb, Th, U and several rare earth elements (REEs) (La, Ce, Pr, Nd, Gd, Dy, Er, Sm and Eu) from SRM 1648 and SRM 2783. A small amount of HF in the first stage was required to dissolve silicates necessitating the corresponding addition of H3BO3 in second stage to dissolve fluoride precipitates of Mg, La, Ce and Th. The optimized microwave dissolution—ICP-MS method detected Na, Mg, Al, K, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Cd, Mo, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Gd, Pb, Th and U at trace to ultra-trace levels in ambient airborne fine particles from three sites in North Carolina. La to light lanthanide signature ratios suggested that soil and motor vehicles are the dominant REE sources in SRM 2783 and PM2.5 samples collected during this study.  相似文献   

12.
The National Analytical Reference Laboratory of the Australian Government Analytical Laboratories was initially accredited to ILAC Guide G 12:2000 in January 2000 and is currently accredited to ISO Guide 34 (2000) for the production of a range of pure organic substance reference materials. This paper discusses the practical challenges and rewards of developing and implementing a quality system for reference material production and discusses some of the barriers, and potential solutions, to more general implementation of third-party accreditation.  相似文献   

13.
Semi-automatic capillary gas chromatographic method with classical flame ionization detection, which satisfies the conditions for required performance and gave acceptable results within the framework of an interlaboratory certification programme for PAHs in sewage sludge, is described. The interesting feature of the procedure is that it incorporates automatic operations such as sample fractionation by semi-preparative HPLC, fraction collection at signal level recognition and evaporation under nitrogen flow. Multiple injections in the GC capillary column are performed in the on-column mode via an autosampler with temperature-programmable injector. Automatic data acquisition and chromatogram treatment are made via computer software. This partially automatic procedure releases personnel from tedious and time-consuming tasks and its robust character was validated through the certification of reference material for PAHs in sewage sludge, demonstrating its reliable performance.  相似文献   

14.
Oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) have recently received much attention in discussions regarding the negative impacts of particulate matter (PM) on human health and the environment. The National Institute of Standards and Technology provides several environmental matrix standard reference materials (SRMs) with certified and reference values for polycyclic aromatic hydrocarbons (PAHs) and nitrated PAHs. In this study, the concentrations of oxygenated PAHs are determined in three air PM SRMs (1649b, 1648a, and 2786) and three diesel PM SRMs (1650b, 2975, and 1975) using two independent gas chromatography–mass spectrometry methods. Concentrations of oxy-PAHs were at the milligrams per kilogram level with higher overall concentrations in diesel PM (up to 50 mg/kg for 9,10-anthraquinone). One of the highest oxy-PAH concentrations (up to 5 mg/kg) measured in the air particulate SRMs was for 7,12-benz[a]anthracenquinone. These results suggest that oxygenated PAHs should not be neglected in the analysis of PM as their concentrations can be as high as those of some PAHs and are one to two orders of magnitude higher than those for nitro-PAHs.  相似文献   

15.
ELISAs (enzyme-linked immunosorbent assays) are generally used in environmental analytical chemistry for screening purposes. In this work the applicability of a polyclonal-based 1-nitropyrene-ELISA for the quantification of the target analyte in air particulate matter was investigated. Validation was performed using an HPLC method with fluorescence detection of the reduced form of 1-nitropyrene. It was found that the immunoassay is not only sensitive for the target analyte but to a certain extent also for other cross-reacting molecules present in the sample, such as 2-nitropyrene and 2-nitrofluoranthene, which were identified by GC-HRMS and are considered to be products of photochemically induced reactions of pyrene or fluoranthene, respectively. The degree of correlation between ELISA and HPLC results for collected samples of air particulate matter was inversely dependent on the distance between the sampling location and the source. Received: 20 August 1997 / Revised: 25 November 1997 / Accepted: 27 November 1997  相似文献   

16.
Summary A procedure is described for the spark source mass spectrometric analysis of a large number of trace constituents in airborne particulate matter and fly-ash. A simple sample preparation procedure and a fully automatic photoplate analysis allows determination of ca. 50 elements with a precision of 20% within 4–5 h.
Analyse von Luftstaub und Flugasche mit der Funken-Massenspektrometrie
Zusammenfassung Es wird ein Verfahren zur Bestimmung einer großen Zahl von Spurenbestandteilen in Luftstaub und Flugasche mit Hilfe der Funken-Massenspektrometrie beschrieben. Eine einfache Probenvorbereitung und eine vollautomatische Photoplattenauswertung erlaubt die Bestimmung von etwa 50 Elementen mit einer Genauigkeit von 20% innerhalb von 4–5h.
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17.
Matrix reference materials are an essential component for the validation and quality control of analytical methodologies for the quantitation of marine biotoxins in shellfish. Given the potential advantages of reference materials in powder form, a study was conducted to assess the feasibility for the production of a freeze-dried oyster tissue reference material containing a range of important paralytic shellfish poisoning toxins. One bulk sample of a wet oyster tissue homogenate was generated following mass culturing of toxic Alexandrium and oyster feeding experiments. The bulk tissue was used to prepare untreated wet frozen aliquots with the remainder being freeze-dried and processed into appropriately-sized powder samples. A pre-column oxidation LC-FLD analysis was used to confirm the absence of any chromatographic artefacts resulting from the processing and to confirm acceptable homogeneity of the tissues. Excellent stability over both the short-term (1 month) and long-term (1 year) of the freeze-dried material was demonstrated as compared with the stability of the untreated wet tissue. A post-column oxidation LC-FLD method was used to confirm the absence of toxin epimerisation in freeze-dried tissues which were observed in the wet tissues. Overall the work showed the feasibility of an approach to produce a homogenous freeze-dried oyster matrix material with enhanced stability in comparison to the untreated wet tissue. The potential for use of the process for preparation of large scale production batches of a freeze-dried CRM for paralytic shellfish poisoning toxins has therefore been demonstrated.  相似文献   

18.
ELISAs (enzyme-linked immunosorbent assays) are generally used in environmental analytical chemistry for screening purposes. In this work the applicability of a polyclonal-based 1-nitropyrene-ELISA for the quantification of the target analyte in air particulate matter was investigated. Validation was performed using an HPLC method with fluorescence detection of the reduced form of 1-nitropyrene. It was found that the immunoassay is not only sensitive for the target analyte but to a certain extent also for other cross-reacting molecules present in the sample, such as 2-nitropyrene and 2-nitrofluoranthene, which were identified by GC-HRMS and are considered to be products of photochemically induced reactions of pyrene or fluoranthene, respectively. The degree of correlation between ELISA and HPLC results for collected samples of air particulate matter was inversely dependent on the distance between the sampling location and the source.  相似文献   

19.
Air particulate matter collected between July and October 1990 at a site located close to an industrial estate in Lagos, Nigeria were analyzed for 18 elements by Wavelength Dispersive X-ray Fluorescence Spectroscopy (XRF) and Atomic Absorption Spectroscopy (AAS). Varimax rotated factor analysis was used for source identification of the coarse and fine fractions. For the coarse fraction, the major sources are: Re-entrained soil, Sea-salt, Industry, Regional sulphate and fresh automobile exhaust. For the fine fraction, the sources identified are Re-entrained soil, Vehicle exhaust, Sea-salt, and Industrial processes. Two other sources which are likely to be due to specific industrues come out in the fine fraction but they have not been clearly identified.  相似文献   

20.
A speciation method was developed for the determination of inorganic indium compounds in the particulate matter of emissions and from the workplace, based on selective sequential extractions. The main inorganic indium compounds that are expected to be present in the atmospheric particulate matter involving the industrial production of indium and in the manufacture of indium compounds were separated and determined. The procedure has been tested on standard reference materials. The indium recovery was in the range 93 - 105%.  相似文献   

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