“Soil analysis by thin-film energy-dispersive X-ray fluorescence”. Van Grieken R, Van 't dack L, Costa Dantas C, Da Silveira Dantas H, Analytica chimica acta 108, 93 (1979). http://doi.org/10.1016/S0003-2670(01)93044-2
Abstract: Energy-dispersive x-ray fluorescence is advantageous for trace analysis of soils present as thin films. A target thickness of about 2 mg cm-2 provides a compromise between optimal sensitivity and minimal absorption effect or optimal accuracy. Sample preparation involves only suspending the finely ground soil in water and drying this suspension on a thin mylar foil glued on a ring that fits into the x.r.f. spectrometer. The effective sample weight present in the exciting beam area is computed from the scatter peaks, a method that cancels out target heterogeneity problems. High accuracy is demonstrated for many elements in reference soil and rock materials; a precision around 5% and a detection limit around 10 ppm can be achieved. As an illustration, results for 16 trace elements and preliminary interpretation are given for a series of pedologically important soil samples from Brasil.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0003-2670(01)93044-2
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“Radio-isotope neutron activation analysis for vanadium, manganese and tungsten in alloy steels”. Lins Galdino SM, Costa Dantas C, Van Grieken R, Analytica chimica acta 196, 337 (1987). http://doi.org/10.1016/S0003-2670(00)83107-4
Abstract: An instrumental neutron activation method for V, Mn and W in alloy steels with a 241 Am/Be isotopic neutron source is described. The samples were irradiated to induce the nuclear reactions 51V(n, γ) 52V, 55Mn(n, γ)56Mn, and 186W(n, γ)187W. The activities were measured with a NaI(TI) detector. Interferences on the measured photopeaks were shown to be negligible by measuring the half-lives of 62V, 56Mn and 187W.These thre elementes were determined in the range 1.512.9% in special steels; manganese in the range 0.51.6% was measured in cast irons. Calibration was done by comparison with results from wet chemistry and x-ray fluorescence spectrometry. The processing times for the vanadium, manganese and tungsten determinations were 11 min, 3 h and 26.3 h, respectively, but these were reduced greatly by intoruding a scheme wherein six samples were simultaneously irradiated and the 56Mn and 187W nuclides were measured sequentially for a series of 66 samples. The average processing time was reduced to 45 min for tungsten with a precision of 4.0% and accuracy of 3.4% and 22.8 min for manganese with a precision of 3.8% and accuracy of 3.1%.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0003-2670(00)83107-4
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“Elemental constituents of atmospheric aerosols in Recife, North-East Brazil”. Van Grieken R, Van 't dack L, Costa Dantas C, Moura de Amorim W, Maenhaut W, Environmental pollution: series B : chemical and physical 4, 143 (1982). http://doi.org/10.1016/0143-148X(82)90025-8
Abstract: Few data are available on the inorganic atmospheric pollution in the rapidly expanding cities of South America, like Recife, on the Atlantic Coast of North-east Brazil. Therefore, the elemental composition of atmospheric aerosols was investigated for nine sites in the Recife conurbation and a fairly remote site in the area. Total aerosol samples were collected on cellulose filters for analysis by energy dispersive X-ray fluorescence and cascade impactors were used to collect the aerosols as a function of particle size for subsequent analysis by proton-induced X-ray emission. Local soil aliquots were also analysed. About eighteen elements were quantified in all cases. The average total atmospheric concentrations appeared to be well above natural levels but usually lower than, or comparable with, those of North American and European cities. Dispersal of sea spray and of local soil (often contaminated with, for example, Cu, Zn and Pb from industrial sources) contributes predominantly to the total atmospheric load in Recife. However, the particle size fraction results also indicated strong excesses in the small particle mode for S, K, V, Mn, Ni, Cu, Zn, Br and Pb, mainly in the downtown area. Again, the corresponding enrichment factors were only moderate in comparison with other published urban data.
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0143-148X(82)90025-8
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“Analise de solos por meio de fluorescencia de raios-X nao-dispersiva”. Costa Dantas C, Da Silveira Dantas H, Van 't dack L, Van Grieken R, Química nova 4, 110 (1981)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Trace elements in the atmospheric aerosols and soils in and around Recife, N.E. Brasil”. Costa Dantas C, Moura de Amorim W, Van 't dack L, Van Grieken R, Ciencia e cultura 32, 1525 (1980)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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