Trace elements in Australian opals using neutron activation analysis

Neutron activation analysis was used to determine the concentration of trace elements in 42 samples of black, grey and white opals taken from a number of recognised Australian field. The results were evaluated to determine if a relationship existed between trace element content and opal colour.     

Trace elements in precious and common opals using neutron activation analysis

Neutron activation analysis (NAA) was used to determine the concentration of trace elements in 44 precious and 52 common opals sampled from a number of recognised fields within Australia. The purpose of this study was to determine if precious and common opals of the same colour and location have the same or a different trace element profile. Similar numbers of black, white and grey samples were studied in each case. In most cases common opals had a significantly higher concentrationof certain trace elements when compared with precious opals.     

Trace elements archeochemistry in different sigillated potteries,using neutron activation analysis

The study concerns sigillated potteries coming from French as well as from Italian workshops. The determination of trace elements was performed by neutron activation analysis applying an analytical procedure described previously.     

Trace elements in human bone determined by neutron activation analysis

There is an evidence that some of the essential trace elements are crucial determinants of bone health. Excess or deficiency of these elements has a role in the development of bone diseases, therefore research on trace elements in bone is very important. Iliac crest bone biopsies were optioned from twelve persons undergoing orthopedic surgery due to any reason than osteoporosis. Cortical and trabecular parts were separated, and blood and fats were removed. Up to 30 minor and trace elements were determined in these samples by instrumental neutron activation analysis and other techniques and their relations were discussed.     

Trace elements distribution in Antarctic sediments by neutron activation analysis

In the present investigation iron and trace elements were determined by instrumental neutron activation analysis in a number of sea bottom sediment samples, collected in the Ross Sea and close to the Italian Station at Terra Nova Bay in Antarctica. Full listing of results is presented and discussed as well as the evaluation of precision and accuracy. In order to find correlations and similarities among the sediment samples, the analytical data were submitted to statistical treatment. In addition rare earth element patterns were obtained. Typical trends were observed with no evident Eu negative anomaly and a depletion of heavy rare earth elements.     

Trace elements in Turkish tobacco determined by instrumental neutron activation analysis

The concentration of 20 trace elements in nine different brands of Turkish cigarette tobacco and in a brand of pipe tobacco and in tobacco ash has been determined by instrumental neutron activation analysis. The percent transference of elements into smoke has been estimated from the amounts remaining in the ash.     

Trace analysis of ancient gold objects using radiochemical neutron activation analysis

Radiochemical neutron activation analysis has been applied to investigate the microelements in gold samples with archaeological importance. Chemical separation has allowed the determination of traces of Ir, Os, Sb, Zn, Co, Fe, Ni. Instrumental neutron activation analysis has been used for the determination of Cu.     

Trace element concentrations in human bone using instrumental neutron activation analysis

Instrumental neutron activation analysis has been applied to analyze 23 bone samples obtained from Libyan patient aged (3–80) years for the study of the concentration levels of trace elements Ba, Br, Ca, Fe, Sr and Zn and their concentration pattems regarding to the age and sex of the patients.     

Trace element concentration in human gallstones using instrumental neutron activation analysis

The concentrations of trace elements in two types of gallstones in 24 female patients in Tripoli aged 24–60 years have been determined using instrumental neutron activation analysis. These elements are Co, Fe, Mn, Se and Zn. The results are expressed in ppm and are in agreement with reported values. The data suggested that the concentrations of trace elements increase with age.Presented at the MTAA-8 Conference, September 16–20, 1991, Vienna, Austria.     

Trace elements monitored with neutron activation analysis during neurodegeneration in brains of mutant mice

Summary Our objective was to test the efficacy of neutron activation analysis (NAA) for monitoring trace elements in discrete brain regions of wild-type and mutant mice (weaver)with well-documented spatiotemporal patterns of neuronal loss in the cerebellum. As neuronal degradation is accompanied by upregulation of metalloenzymatic activity, we used NAA to detect any transient elevation in elemental composition of brain tissue. Zinc and copper concentrations in the cerebellum of weaver mice aged 5 days greatly exceed levels observed in normal mice or in the weaver's forebrain, which is unaffected by neurodegeneration. Furthermore, concentrations of copper and zinc follow the spatiotemporal pattern of neurodegeneration observed in the cerebellum of weaver mutant mice.     

Trace elements in 11 fruits widely-consumed in the USA as determined by neutron activation analysis

While there is a lot of information on the elemental content of food for nutritional and pollution studies, the analysis of fruits has received little attention. We have investigated 11 commonly eaten fruits for their trace and minor element constituents by neutron activations including thermal and epithermal neutron activation analysis. Our results revealed that both blueberries and strawberries had the most of top two highest elemental concentrations followed by raspberries, oranges and mango. Bananas, grapes, plums, apples, pears, and cherries had the fewest or none of the most elevated elemental concentrations.     

Preconcentration of trace elements for neutron activation analysis using activable tracers

Use of an enriched isotope as an activable tracer is proposed for the preconcentration of trace elements in neutron activation analysis. As a test of this method, contents of cadmium in various biological standard samples were determined by addition of an enriched¹¹⁶Cd tracer in the preconcentration step followed by neutron irradiation and -ray spectrometry. The principle, advantage, and limitations of the method are also discussed.     

Determination of trace elements in human brain tissues using neutron activation analysis

Neutron activation analysis was applied to assess trace element concentrations in brain tissues from normal (n = 21) and demented individuals (n = 21) of both genders aged more than 50 years. Concentrations of the elements Br, Fe, K, Na, Rb, Se and Zn were determined. Comparisons were made between the results obtained for the hippocampus and frontal cortex tissues, as well as, those obtained in brains of normal and demented individuals. Certified reference materials, NIST 1566b Oyster Tissue and NIST 1577b Bovine Liver were analyzed for quality of the analytical results.     

Determination of Hg and other trace elements in soil using neutron activation analysis

In the early 1950's, a federal facility in Oak Ridge, Tennessee, used a process that required the use of Hg to produce⁸Li. It was disclosed to the public in 1983 that about 2.4 millions pounds of Hg had been released into the ecosystem. The primary route of mercury into the environment was a stream, East Fork Poplar Creek, whose head waters are in the vicinity of the plant. As part of a study to determine the distribution of Hg as well as As, Cr, Sb, Se, U, and Zn along the flood plains of the creek, a procedure using neutron activation analysis was developed and is described below. The procedure, typical sample analysis results for Hg, and quality assurance and control data are discussed in this paper.     

Determination of trace elements in tobacco using different techniques of neutron activation analysis

Quantitative data on trace elements in two tobacco leaf (candidate) reference materials OTL-1 and VTL-2 prepared by the Polish Academy of Sciences and the Institute of Nuclear Chemistry and Technology, Warsaw, Poland, are presented and compard to recommended values, where available. By instrumental neutron activation analysis (INAA), as well as by radiochemical technique (RNAA) 30 elements were quantitatively determined and fair agreement was found between the results and recommended values for the first material.     

Determination of rare earth elements in fern leaves using instrumental neutron activation analysis

The lanthanides (REE) in 142 fern leaves collected from several sampling sites in Japan have been determined by neutron activation analysis, and the correlations between any two REEs in the logarithmic scattering diagram were examined. The relationship was expressed by the general formula, Y=aX+b with a correlation coefficient R. A strong positive correlation was seen between any two REEs in the diagram with a regression coefficient and a correlation coefficient close to unity. However, between Eu or Tb and other REEs the relationship was split into two lines with the same correlation coefficient. From the intercept b, the relative abundance of the two elements was determined for each REE and compared with those in hickory and tobacco leaves. These findings indicated that the abundance pattern of fern leaves is quite different from those of hickory and tobacco leaves. Namely, the relative abundance of La and Ce was quite similar in the three plants, but the abundance of the other REEs (Nd, Sm, Gd, Dy and Lu) was considerably lower in ferns than in hickory and tobacco leaves. For Eu and Tb the higher values obtained in fern leaves coincided with those of the two plants.     

Trace multielement analysis in boron materials by epithermal neutron activation analysis

A method, based on epithermal neutron activation analysis using a boron filter is described for the determination of ～60 trace elements in boron and its compounds. The method has an accuracy of ～20%, a precision of ～15% RSD and limits of detection for most elements are either at the sub-ppm or low ppm levels. The method requires no sample preparation and is economical in effort.     

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     

Trace element analysis of some shaving powders commonly marketed in Nigeria using instrumental neutron activation analysis

Instrumental neutron activation analysis (INAA) technique has been employed viak ₀ approximation method to determine elemental composition of five shaving powders commonly marketed in Nigeria. Fe displayed the highest concentrations in the range 1000–2000 g·g^–1. Na and Zn concentrations were established in the range 200–400 g·g^–1. Heavy elements like Ga, La, Cr, Co, Ag, Ce and Nd concentrations were noted in the lower range of 1–10 g·g^–1 Br, As, Sb, Sm, Eu, W, Cs, Tb, Yb, Hf, Ta, Th and U concentrations were established in even lower traces in the <1 g·g^–1 range. Results obtained for a certified reference material, CANMET BL-1 and CERT (in house) Kaolin standard compared favourably with the literature values thus establishing the results presented for the shaving powders.     

The determination of trace elements in new food grain SRM's using neutron activation analysis

Potentially toxic metals in the food chain that can lead to deleterious effects on human health have been well documented. Because of the toxicity of some metals, levels of 1 ppm or less must be routinely monitored in foods to ensure human safety. To ensure the accuracy of measurement, NBS in a cooperative interagency agreement with the Food and Drug Administration is involved in developing and certifying selected elements in food grain as a part of the Standard Reference Material program. Both instrumental and radiochemical neutron activation analysis were used to analyze two food grain standard reference materials (Rice and Wheat Flours) for trace element certification.