Determination of heavy metals in welder's working environment using nuclear analytical methods

Technological process of welding is significant source of pollution of working environment with heavy metals. Evaluation of chemical quality of working environment was made by means of radionuclide X-ray fluorescent analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed.     

A study of deuteron-induced delayed X-rays from some transition elements

High resolution K X-ray spectrometry preceded by activation with deuterons is an unexplored area in the field of activation analysis. This work describes the capabilities of this technique and evaluates its analytical potential for the specific determination of transition metals in small samples. Detection of the delayed X-rays coupled with their rate of decay provided a unique indication of the target component and its concentration. Analytical conditions are demonstrated for the elements of interest and the potential for application to the general routine determination of the transition metals and some of their isotopes, is discussed.     

Determination of chromium/VI/ in welding fumes by radionuclide X-ray fluorescent analysis

From all heavy metals being the most significant particulates of air pollutants at working of high-alloy steels from the toxicological viewpoint, chromium is paid main attention at present in many laboratories. Continuing the work in the field of radionuclide X-ray fluorescent analysis of welding aerosols we have suggested and carried out a method for quick Cr/VI/ determination by means of²⁴¹Am radionuclide excitation of characteristic X-ray fluorescent radiation and Si/Li/ spectrometer.     

Effect of additional excitation in the X-ray fluorescence determination of noble metals in unsaturated beds

The relative contribution of effect of additional excitation of iridium and gold atoms appearing in unsaturated beds in using substrate from corresponding material is studied. The mathematical design of experiments is used to rank factors affecting the analytical parameters of X-ray fluorescence analysis in the determination of noble metals.     

Comparison of the Results of Atomic Absorption and X-ray Fluorescence Analysis of Metals in Atmospheric Aerosols

Factors responsible for the systematic discrepancies between the results of atomic absorption (standard procedure) and X-ray fluorescence determination of metals in atmospheric aerosols preconcentrated on a filter were studied. Patterns describing the errors in the results of determining Fe, Cu, Pb, Zn, Mn, and Cr by the proposed procedures depending on the type of the metal compound and the concentration of SiO₂ in aerosol particles were found. It was shown that the underestimation of the results of atomic absorption analysis in comparison to those obtained by X-ray fluorescence is due to the incomplete decomposition of some analyte compounds and the adsorption of Fe, Cu, and Pb on the precipitated SiO₂.     

Simultaneous Determination of Microgram Amounts of Platinum and Palladium in Presence of Base Metals by Isolation on Anion Exchange Resin-Loaded Paper and X-Ray Spectrometry

Abstract

A procedure for simultaneous determination of microgram amounts of platinum and palladium in solutions of base metals is described. The two metals are isolated on an anion exchange resin-loaded paper disk and determined by X-ray spectrometry. The method is applied to the determination of platinum and palladium in nickel matte.     

Contribution to the radioanalytical determination of heavy metals in the working environment of welders

Heavy metals can be the most important toxic substances in welding environments. Their chemical behavior is related to welding aerosols; hence, reliable analysis of these aerosols is quite important. Activation analysis by fast neutrons (14 MeV), and radionuclidic X-ray fluorescence analysis (241-Am source) were used to determine selected metals (Fe, Mn, Cr, Ni, Mo) in aerosols produced during welding of high-alloy steels with MIG technology. Sampling was done by filtration using micro-pore filters. A multichannel analyzer (MCA S80 CANBERRA) and Si/Li, Ge/Li detectors were used to process the analytical signals. Appropriate statistical parameters were calculated.     

Analytical possibilities of different X-ray fluorescence systems for determination of trace elements in aqueous samples pre-concentrated with carbon nanotubes

This study was aimed to achieve improved instrumental sensitivity and detection limits for multielement determination of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Se, Pb and Cd in liquid samples by using different X-ray fluorescence (XRF) configurations (a benchtop energy-dispersive X-ray fluorescence spectrometer, a benchtop polarised energy-dispersive X-ray fluorescence spectrometer and a wavelength-dispersive X-ray fluorescence spectrometer).The preconcentration of metals from liquid solutions consisted on a solid-phase extraction using carbon nanotubes (CNTs) as solid sorbents. After the extraction step, the aqueous sample was filtered and CNTs with the absorbed elements were collected onto a filter paper which was directly analyzed by XRF.The calculated detection limits in all cases were in the low ng mL^− 1 range. Nevertheless, results obtained indicate the benefits, in terms of sensitivity, of using polarized X-ray sources using different secondary targets in comparison to conventional XRF systems, above all if Cd determination is required.The developed methodologies, using the aforementioned equipments, have been applied for multielement determination in water samples from an industrial area of Poland.     

电感耦合等离子体-质谱联用及其在环境和生物样品中铂族金属分析的应用进展

本文简述了电感耦合等离子体-质谱联用(LCP-MS)技术和仪器的发展,分析了环境和生物样品中铂族金属分析的主要困难,综述了90年代以来国内外ICP-MS技术在环境和生物样品中铂族金属分析的最新进展,引用文献47篇.     

Analysis of water-soluble fraction of metals in atmospheric aerosols using aerosol counterflow two-jets unit and chemiluminescent detection

A new analytical system for a semi-continuous analysis of water-soluble fraction of particulate metals is described. The system combines the continuous sampling of atmospheric aerosols into deionized water using the Aerosol Counterflow Two-Jets Unit and on-line chemiluminescent detection of water soluble fraction of metals in collected aerosols. The potential of analytical system was studied using Fe³⁺, Cu²⁺ and Co²⁺ as model metals in atmospheric aerosols. The detection limits of particulate Fe³⁺, Cu²⁺ and Co²⁺ (S/N?=?3) are 24, 41 and 0.4?ng?m^?3, respectively. The presented set-up allows the determination of concentration of water-soluble fraction of particulate metals in ‘real time’ with time resolution of 30?min. The system is sufficiently robust for the field application. The method has been applied to the measurement of selected metals in urban TSP (Total Suspended Particles) aerosols in Brno in the Czech Republic. The concentrations of particulate water-soluble Fe³⁺, Cu²⁺ and Co²⁺ were found in the range of 35 to 290, 42 to 462 and 0.5 to 9?ng?m^?3, respectively.     

X-ray determination of traces of hafnium in zirconium metal or traces of zirconium in hafnium metal after separation by ion exchange

A method is proposed for the determination of traces of hafnium in zirconium metal or zirconium in hafnium metal. The trace metals are first separated from the matrix metals on an ion-exchange column and then determined by X-ray analysis.     

Direct and rapid determination of elements in the ambient air and in human exhalation using the electrostatic precipitation of aerosols in the graphite atomizer of a zeeman spectrometer

The use of a new Zeeman spectrometer with the electrostatic precipitation of aerosols in the graphite furnace of the atomizer for the direct and rapid determination of aerosols in the ambient air and in the air exhaled by human beings is presented. The results are given for the comparative determination of elements in laboratory air by electrostatic precipitation and with the filter accumulation of aerosols. A correlation is found between the concentration of Se in the exhaled air and its concentration in the examinee’s blood.     

Recent advances in the determination of low level plutonium in environmental and biological materials

The present paper reviews briefly the recent advance in radioanalysis of low level plutonium in environmental and biological samples. Lots of new radiochemical methods for determination of plutonium in aerosols, natural waters, soil, sediments and various biological materials have been developed. The use and prospects of several radiochemical procedures are discussed.     

New method for resolving the enantiomeric composition of 2-methyltetrols in atmospheric organic aerosols

In order to facilitate the determination of the primary and secondary origin of atmospheric organic aerosols, a novel method involving chiral capillary gas chromatography coupled with mass spectrometry has been developed and validated. The method was focused on the analysis of 2-methylerythritol and 2-methylthreitol, considered to be tracers of secondary organic aerosols from the oxidation of atmospheric isoprene. The method was validated by performing various tests using authentic standards, including pure enantiomeric standards. The result showed that the analytical method itself does not affect the enantiomeric composition of the samples analyzed. The method was applied on atmospheric aerosols from a boreal forest collected in Aspvreten, Sweden and on laboratory samples obtained from liquid phase oxidation of isoprene and smog chamber experiments. Aerosol samples contained one enantiomer of 2-methylerythritol in significantly larger quantities than the others. In contrast, the liquid-phase oxidation of isoprene and its gas-phase oxidation in the smog chamber produced all enantiomers in equal quantities. The results obtained where the enantiomer fraction, EF, is larger than 0.50 suggest that 2-methyltetrols in atmospheric aerosols may also have biological origin. Information about the differences between enantiomer fractions obtained using this method brings new insights in the area of atmospheric aerosols.     

Characterization of anthropogenic sediment particles after a transboundary water pollution of river Tisza using synchrotron radiation

At the beginning of 2000, a major mining accident occurred in the Romanian part of the Tisza catchment area due to tailings dam failure releasing huge amounts of heavy metals to the river. Sediment samples were taken from the main riverbed at six sites in Hungary, on March 16, 2000. The objective of this work was to characterize the anthropogenic particles in river sediment previously selected by single-particle electron probe X-ray microanalysis (EPMA). The trace element composition, heterogeneity and heavy metal speciation of individual particles was studied using synchrotron radiation-based microbeam X-ray emission and absorption methods. Particles were selected only from samples regarded as polluted sediment. White-beam micro X-ray fluorescence (μ-XRF) allowed the quantitative determination of heavy metals such as cadmium in individual particles. The maximum observed concentration of cadmium (>700 μg/g) indicates that this highly toxic heavy metal is concentrated in individual anthropogenic particles. Using the combination of micro X-ray absorption near-edge structure and target-transformation principle component analysis, quantitative chemical speciation of copper and zinc was feasible on individual sediment particles. Heavy metals in most of the particles released from the pollution site remained in the sulfide form resulting in a limited mobility of these metals. Based on the information obtained using microanalytical methods, the estimation of the environmental mobility of heavy metals connected to microparticles becomes possible.     

Determination of metals in lubricating oils by X-ray fluorescence spectrometry

The determination of common wear metals, namely iron, chromium, copper, zinc and lead, in a wide range of lubricating oil samples was investigated for the use of a low-cost, wavelength-dispersive X-ray fluorescence spectrometer. The procedure provided results in satisfactory agreement with inductively coupled plasma spectrometry used as reference method after microwave digestion of the samples in concentrated nitric acid. Statistical tests following extensive regression analyses of the data indicated that interelement effects were not statistically significant and that a simple linear regression was adequate for the calibration of individual metals.     

Thickness determination for Cu and Ni nanolayers: Comparison of completely reference-free fundamental parameter-based X-ray fluorescence analysis and X-ray reflectometry

Monochromatized synchrotron radiation of the electron storage ring BESSY II has been used for the non-destructive thickness determination of nanolayered materials by two different methods. The aim of these investigations was the comparison of completely reference-free fundamental parameter-based X-ray fluorescence analysis with X-ray reflectometry to validate the quantification of X-ray fluorescence analysis as an absolute method. For this purpose, Cu and Ni layers with a thickness varying between 5 nm and 50 nm as well as double layers of both metals deposited on Si have been studied. In X-ray reflectometry characterization experiments, the tunability of the photon energy allows the determination of not only the total layer thickness but also the individual layer thicknesses of the Cu/Ni double-layer systems. Reference-free X-ray fluorescence analysis involves both the fundamental parameter approach and the knowledge of all relevant experimental parameters obtained by instrumentation calibrated absolutely.The layer thickness determined by both methods agreed within their combined uncertainties. In view of the limits of X-ray reflectometry for very thin layers, laterally inhomogeneous samples, and multi-elemental layer compositions, reference-free X-ray fluorescence analysis offers the potential for the thickness determination of such samples.     

Determination of trace elements in metals by atomic absorption spectrometry with introduction of solid samples into furnaces: An appraisal

The determination of trace elements in metals by atomic absorption spectrophotometry with introduction of solid samples into furnaces has been reviewed from the first paper in 1965 until the present day. The need for this type of analysis is considered along with other analytical techniques that can provide useful information. Early developments up to 1975 are presented and discussed but the main emphasis is on work undertaken during the past five years. Information is provided on homogeneity of samples, methods of calibration, accuracy, precision and limits of detection to show that this technique is the most convenient available for the determination of volatile trace elements in metals at concentrations less than 10 μg g⁻¹.     

Voltammetric methods for the determination of heavy metals in domestic waste and compost produced from it

Methods of sampling an preparation of waste and compost samples for analysis are described. A voltammetric method has been used for the determination of the contents of toxic heavy metals (one of the most important criterion for compost quality evaluation) in domestic waste and in compost produced from it. A novel method was proposed for the UV mineralisation of water extracts obtained during leaching of waste and compost samples. Copper, lead, zinc and cadmium were determined in wet-digested samples of domestic waste, compost and its extracts by anodic stripping voltammetry. Nickel and cobalt were determined by adsorption voltammetry. The determination of five metals in one sample over a wide range of concentrations and the low cost of the apparatus used are the main advantages of the analytical method described. This has been shown by the determination of the metals in fractions of domestic waste, in compost produced of that waste and in compost mixed with sewage sludge. Special attention has been paid to investigations of the mobilisation of metals from waste and compost during the leaching test.     

Mechanism and Kinetics of Heterogeneous Reactions of Unsaturated Organic Acids on α‐Al2O3 and CaCO3

Heterogeneous reactions have a vital role in the atmosphere due to their significant effects on the evolution of atmospheric aerosols, which in turn contribute to air pollution. However, the mechanism and kinetics of these processes involving unsaturated organic acids, important types of volatile organic compounds, are still unclear. In this work, the heterogeneous uptake of two representative atmospheric unsaturated organic acids (acrylic acid and methacrylic acid) on mineral aerosols including α‐Al₂O₃ and CaCO₃ are investigated using a Knudsen cell reactor and an in situ diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) reactor. The corresponding reaction pathways are proposed from the DRIFTS analysis. In addition, the initial uptake coefficients of unsaturated organic acids and their heterogeneous fate are obtained for the first time. Our results suggest that heterogeneous reactions on α‐Al₂O₃ and CaCO₃ can be important sinks for acrylic acid and methacrylic acid, as well as possible contributors to the organic coating found on atmospheric aerosols, especially in high‐pollution events.