Investigation of the vertical distribution of major and trace elements in Matita Lake (Danube Delta) sediments by activation analysis

The vertical profiles of two major elements (Na and Ca) and 24 trace elements (Rb, Cs, Sr, Ba, Sc, La, Ce, Sm, Eu, Tb, Yb, Lu, Th, U, Hf, Nb, Ta, Cr, Fe, Co, Zn, As, Sb and Br) have been investigated by neutron activation analysis in a 2.5 m core collected from the Danube Delta, Matita Lake. The data have been correlated with the concentrations of five major minerals (calcite, dolomite, feldspar, clay and quartz) as determined by X-ray diffration. This study revealed the presence of As, Sb and Br as pollutant microelements.     

Elemental content in ground and soluble/instant coffee

The concentration of thirty-four elements in twelve coffee brands has been measured using instrumental neutron activation analysis. The samples investigated included four brands of commercially available ground coffee and eight brands of soluble/instant coffee. The elements measured were Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, K, La, Lu, Mg, Mn, Na, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Tm, U, V, Yb and Zn. Twenty four elements were found to be below the detection limit in one or more samples. These elements were Ce, Cr, Fe, V, As, Eu, Ba, Dy, Gd, Hf, La, Lu, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Yb, Tm, and U.     

A systematic neutron activation analysis of peat from Burundi

Mean concentrations of Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Ga, Hf, Ho, I, K, La, Lu, Mg, Mn, Na, Pr, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Ti, Th, V, W, Yb, and Zr, determined in 6 samples of peat from Burundi, were equal to 3911, 1.7, 0.025, 33, 21, 472, 14, 55, 4.2, 16, 0.43, 14, 0.27, 14675, 1. 2, 1.5, 0.09, 2.9, 203, 5.6, 0.29, 745, 20, 70, 1.5, 13, 2.1, 6.5, 0.8, 6, 0.4, 0.2, 2.9, 392, 15.7, 0.43, 0.09 and 101 ppm resp. The peat in Burundi contain approximately the same concentrations of elements as the peat in other countries. It is enriched in Br and depleted in Ca, K, Mn, Na, Sr and Yb.     

Determination of 34 elements in Chinese geochemical standard reference materials by instrumental neutron activation analysis

Thirty four elements (Al, As, Ba, Br, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, Ho, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, Ti, U, V, W, Yb) were determined by instrumental neutron activation analysis in the second set of Chinese geochemical standard reference materials (sediments from GSD-9 to GSD-12, soils from GSS-1 to GSS-8, rocks from GSR-1 to GSR-6) using both thermal and epithermal irradiations. Irradiation schemes designed to utilise short, medium and long-lived nuclides were employed in order to analyse major, minor and trace elements with different half-lives. The gamma-ray spectra were measured by Ge(Li) and HP(Ge) detectors. Relevant nuclear data and possible interferences are listed, and analytical results are presented and discussed.     

Elemental analysis of phosphate rocks: For sustainable agriculture in Pakistan

The concentration of 32 elements was determined in phosphate rock samples from the Hazara phosphate deposits of Pakistan using instrumental neutron activation analysis (INAA) technique employing different irradiation protocols. These included 23 major, minor and trace elements (Al, As, Ba, Br, Co, Cr, Cs, Fe, Ga, Hf, K, Mn, Na, Rb, Sb, Sc, Sn, Ta, Th, U, V, Zn and Zr) and 9 rare earth elements (REEs) namely Ce, Eu, Ho, La, Lu, Nd, Sm, Tb and Yb. The results have been compared with the global values of these elements. The concentrations for most of the elements studied are lower than the concentrations reported in the literature whereas the concentrations of As, Co, Fe, K, Mn, Na and Sb are comparable. Two samples namely HR-4 and HR-5 have the highest concentrations for majority of the REFs with high enrichment factors. The quality assurance of data was performed through the concurrent use of Lake Sediment (SL-1) and GSJ-JR-1 (Rhyolite) reference materials. The acquired data will serve as a reference for the follow-up studies to assess the agronomic effectiveness of the Hazara phosphate rocks.     

57Fe Mössbauer spectroscopy of banded iron formations from eastern India

Samples of the mosses Hylocomium splendens and Pleurozium schreberi, collected in the summer of 1998, were used to study the atmospheric deposition of heavy metals and other toxic elements in the Chelyabinsk Region situated in the South Urals, one of the most heavily polluted industrial areas of the Russian Federation. Samples of natural soils were collected simultaneously with moss at the same 30 sites in order to investigate surface accumulation of heavy metals and to examine the correlation of elements in moss and soil samples in order to separate contributions from atmospheric deposition and from soil minerals. A total of 38 elements (Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Rb, Sr, Zr, Mo, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Au, Th, U) in soil and 33 elements Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Au, Th, U) were determined by epithermal neutron activation analysis. The elements Cu, Cd and Pb (in moss samples only) were obtained by atomic absorption spectrometry. VARIMAX rotated principal component analysis was used to identify and characterize different pollution sources and to point out the most polluted areas.     

Elemental analysis of dust trapped in air conditioner filters for the assessment of Lahore city’s air quality

A study was undertaken to assess the air quality of Lahore by the elemental analysis of air conditioner (AC) filter dust samples collected from 15 different commercial sites. Samples were prepared using the Leeds Public Analyst Method and were analyzed using instrumental neutron activation analysis (INAA) for up to 31 elements. The elements Al, As, Ba, Ce, Co, Cr, Cs, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sc, Sm, Sn, Ta, Th, Yb and Zn were detected in all 15 samples whereas the remaining elements have been detected in fewer samples; i.e. Mg, Sb and Tb were detected in 14 samples, Br and V in ten samples, U in nine samples and Ca and Ti in eight samples only. Al, Ca, Fe, K, Mg and Na were determined in all samples at percentage levels. The concentrations of most elements were found to lie around the mean values for the 15 samples studied and were not orders of magnitude different. However the concentrations of Ca, Mg, Sn and Zn were found to be more variable and were found to be dependant on activities such as construction, fruit and vegetable handling, tin plating and transport, respectively.     

Instrumental neutron activation analysis of trace elements in quartz

A scheme for INAA of 32 elements (As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, W. Yb, Zn) in quartz glass is proposed. The accuracy of the procedure is evaluated by the analysis of two NBS standard reference materials (SRM-1571 and SRM-1632-a). The method is convenient for routine work. The method was used for the determination of impurities in laboratory quartz glass. Dedicated to the 60th birthday of acad. prof. g. bliznakov     

Determination of impurities in titanium and titanium oxide by radiochemical neutron activation analysis

A radiochemical neutron activation analysis has been applied to 2N–4N grade titanium metal and its oxide. Twenty two impurities were separated in a group from scandium by a radiochemical separation method using cation exchange resin with HBr and HCl. The contents of the elements were calculated by a single comparator method using two monitors. The analytical results agree well within 10% deviation with those obtained by instrumental method. Eighteen elements, Na, Fe, Co, As, Se, Sr, Mo, Sb, La, Eu, Tb, Yb, Lu, Hf, Ta, W, Th and U, are determined in titanium oxides and 17 elements, Na, Cr, Fe, Co, Se, As, Zr, Mo, Sb, Cs, Ce, Tb, Yb, Hf, Ta, W and Th, in titanium metals.     

Elemental content in wheat products of Al-Qusim region, Saudi Arabia using the INAA technique

Wheat is one of the most grown crops in Saudi Arabia. It is grown in various regions of the country. Accurate knowledge of the elemental concentrations in wheat and its products (bran and flour) is of great importance from a nutritional point of view. Wheat samples were obtained from the Al-Qusim region, 300 km northwest of Riyadh, and analyzed. Up to 50 elements (Al, Sb, As, Ba, Br, Cd, Ca, Cs, Cl, Cr, Co, Cu, Ga, Au, Hf, In, I, Ir, Fe, Mg, Mn, Hg, Mo, Ni, K, Rb, Sc, Se, Ag, Na, Sr, Ta, Te, Th, Sn, Ti, W, U, V, Zn, Zr, Ce, Dy, Eu, La, Lu, Nd, Sm, Tb and Yb) were determined in the wheat products. It was observed that the elemental content of bran was much higher than that of white flour.     

Elemental characterization of some Nigerian gemstones: tourmaline, fluorite and topaz by instrumental neutron activation analysis

Instrumental neutron activation analysis (INAA) was employed in the determination of the major and trace element constituents in tourmaline, fluorite and topaz collected from the gemstone mineralization within a SW–NE trending pegmatite zone, central Nigeria. Cost, turnaround time, high sensitivity for certain elements, the non-destructive nature of analysis and its precision and accuracy have combined to make INAA an indispensable method for multi-element determination in virtually all geological matrices. The major element constituents in tourmaline were Al (119,800 ppm), Mn (4,348 ppm), Na (15,540 ppm) and Fe (34,290 ppm). For fluorite, Ca was the major element with a concentration of 552,000 ppm. In topaz, Al was the major constituent with a concentration of 322,800 ppm. The data suites reveal the presence of As, Br, La, Sc, Co, Hf, Ta and Sb in tourmaline, Na, As, Br, La, Yb, Co, Zn, Eu, Hf, Th in fluorite and Mg, Mn, Na, Br, La, Sc, Co and Ta as trace contaminants. No attempt was made to identify the molecular structure of the gemstones as oxygen, fluorine and silicon contents in any of them were not determined.     

INAA of Some Fossil Samples from Romanian Sites

Instrumental neutron activation analysis was used to determine elemental contents of Elephas primigenius mammoth mandible bone and Pecten solarium shell fossils discovered in Romania during 1995–1996. In addition, calcareous sedimentary rock surrounding the shell fossil was analyzed. Concentrations of Al, As, Au, Ba, Br, Ca, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Ni, Rb, Sb, Sc, Se, Sr, Th, U, V, Zn and the rare earth elements Ce, Eu, La, Lu, Nd, Sm, Tb, Yb were determined. The results are discussed and compared to the available data in the literature for similar fossils.     

Characterization of deep sea sediments by INAA for radioactive waste management purposes

An instrumental neutron activation analysis method, using both reactor flux and epi-cadmium neutrons, has been developed for the determination of major, minor and trace elements in sub-seabed sediments. The method involves two different irradiations followed by three different counting periods using high-resolution Ge(Li) and low-energy photon detectors. The list of elements determined includes Ag, Al, As, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Dy, Eu, Fe, Ga, Gd, Hf, Hg, I, In, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Pt, Rb, Re, Rh, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Th, Ti, Tm, U, V. W, Yb, Zn, and Zr. The accuracy of the method has been evaluated by analyzing four different standard reference materials. The method has been applied to core samples collected from the Great Meteor East and the South Nares Abyssal Plain which are being evaluated as potential sites for the possible disposal of vitrified highly active waste.     

NAA and ICP analysis of obsidian from Central Europe and the Aegean: Source characterisation and provenance determination

INAA and ICPES are compared for their discriminative power in obsidian source characterisation. Geological samples from the Aegean and Carpathian sources were analysed for Na, Sc, Fe, Co, Rb, Sb, Cs, Ba, La, Ce, Sm, Eu, Tb, Yb, Lu, Hf, Ta, Th, U by INAA and for B, Na, Mg, Al, K, Ca, Sc, Ti, Mn, Fe, Zn, Y, Yr, Cs, Ba, La, Ce, Sm, Eu, Gd, Tb, Yb, Lu, Hf by two ICPES procedures. It is shown that all techniques work successfully, however, INAA is more efficient in the chemical discrimination of neighbouring sources.     

Identification of atmospheric trace-element sources by passive biomonitoring employing PCA and variogram analysis

The epiphyte plant Tillandsia capillaris was used as a passive biomonitor to study the relationship between elemental accumulation and emission sources in the province of Córdoba, Argentina. The concentrations of As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb, and Zn were determined in T. capillaris leaves by Instrumental Neutron Activation Analysis. A variogram analysis was performed to identify the emission sources of these elements in the study area, obtaining different patterns for each element analysed. A principal-component analysis was subsequently performed to further confirm the different contaminant emission sources and it coincided with the results of the variogram analysis. We observed that the enrichment of most elements was associated with natural sources (soil) and that only some elements showed evidence of enrichement related to sources such as traffic (K, Sb and Zn), industries (Br), and mining activity (Ca).     

Determination of elemental levels in radiopharmaceuticals by instrumental neutron activation analysis

Instrumental neutron activation analysis (INAA) was applied to thedetermination of the concentration levels of Na, Mg, Al, Cl, K, Sc, Ti, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, Sb, I, Cs,Ba, La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Lu, Hf, Ta, Hg, Th and U in three radiopharmaceuticals.The irradiation of the samples was carried out in a 0.5 kW Bariloche RA-6Research Nuclear Reactor and the induced gamma-activity was measured by gamma-spectrometry.INAA proves to be an accurate and precise technique to obtain a quick informationon the concentration levels of several minor and trace components in radiopharmaceuticals.The quantification of heavy toxic elements is required for the registrationof radiopharmaceuticals.     

Chemical characterization of gas- and oil-bearing shales by instrumental neutron activation analysis

The concentration of As, Ba, Ca, Co, Cr, Cs, Dy, Eu, Fe, Ga, Hf, K, La, Lu, Mn, Mo, Na, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, Yb, and Zn were determined by instrumental neutron activation analysis in block shale samples of the New Albany Group (Devonian-Mississippian) in the in the Illinois Basin. Uranium content of the samples was as high as 75 ppm and interfered in the determination of samarium, molybdenum, barium and cerium. In the determination of selenium a correction was made for interference from tantalum. U, As, Co, Mo, Ni and Sb as well as Cu, V and pyritic sulphur which were determined by other methods, were found to correlate positively with the organic carbon content of the samples.     

Determination of impurities in semiconductor grade silicon by instrumental neutron activation analysis

Instrumental neutron activation analysis has been applied to semiconductor grade silicon to study the concentration levels of impurity elements, the contamination during the single crystal growing process, and the vertical and radial distributions of impurities, along with the decontamination effect in the analysis. Twenty elements of Au, Br, As, W, Cr, Co, Na, Eu, La, Se, Zn, U, Th, Hf, Fe, Sb, Ag, Ce, Tb and Ta have been analyzed in p- and n-type wafers, single crystals and a polycrystal by a single comparator method using two comparators of gold and cobalt. Considerable surface contamination has been found and could be removed by etching the surface with nitric and hydrofluoric acid before and after irradiation. The impurity concentration has been found to be generally increased in the process of single crystal growth. The vertical and radial distributions of impurities have revealed that some impurity elements were more concentrated in the top region of a single crystal rod than in the middle region, and that Br, Cr, La, Eu and Sb were enriched in the central region and As, U and Fe in the outer region.     

Instrumental neutron activation analysis of pottery for provenience study

A scheme for INAA of pottery is proposed. The combination of 3 irradiations-epithermal and pile (short and long time) and 6 measurements (2 times after each irradiation) enables the determination of Al, As, Au, Ba, Br, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Si, Sm, Ta, Tb, Th, Ti, U, V and Yb. The accuracy and precision of the method is evaluated by analysis of standard reference materials (USGS-BCR-1, USGS-W-1, ZGI-TB). The applicability of the method is demonstrated by analysis of 15 sgraffito ceramics from XV–XVIII cc. from Tzarevetz, Veliko Tirnovo (Bulgaria). The results from the clustering of the analytical data are presented and discussed.     

南极岩石样品中稀土元素的中子活化分析

用仪器中子活化分析技术,测定了南极岩石中8种稀土元素含量,讨论了不同岩石的稀土模式特点。