Substoichiometric determination of chromium by neutron activation analysis

A method of radioactivation analysis has been developed for the determination of chromium. It is based on the substoichiometric extraction of chromium diethyldithio-carbamate into methyl-isobutyl-ketone from acetate buffer solution in the presence of EDTA and potassium cyanide. The method has been applied for the determination of chromium in high-purity calcium carbonate and NBS glasses as standard reference materials.     

Determination of chromium in blood by neutron activation analysis

A procedure for the determination of chromium in blood has been developed with a sensitivity of 5×10⁻³ μg Cr. Dried blood was irradiated with a neutron flux of 10¹² n·cm⁻²·sec⁻¹ in the VVRS reactor for 4 weeks, then the sample was mineralized and the chromium isolated by extraction as perchromic acid. The determination of the chromium content was accomplished by measuring the 0.32 MeV gamma energy of⁵¹Cr. In order to make correction for the interfering reaction⁵⁴Fe(n,α)⁵¹Cr, the formation of chromium from high-purity iron was investigated. The chromium content of the blood samples was between 1.03×10⁻² and 5.2×10⁻² ppm Cr.     

Multielemental analysis of soils by instrumental neutron activation analysis

The results of an instrumental neutron activation analysis of some elemental concentrations in different soil samples near the industrial areas at Tirupati, India, are reported. Altogether 14 elements, Sm, La, Cr, Co, Zn, Cs, Ce, Th, Rb, Na, K, Sr, Fe and Eu were determined. The samples were irradiated with neutrons at the 100 kW Triga - Mainz research reactor and the induced activities were measured by gamma-ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector in connection with a multichannel analyzer. The results are discussed.     

Distribution of aluminum species in normal urine as determined by chemical neutron activation analysis

A procedure developed for separating and quantifying non protein and protein fractions of aluminum species in urine was applied to four consecutive 24 hr collections of five healthy subjects. The total Al content of urine was determined by a chemical neutron activation analysis technique reported elsewhere. Results from the analysis of all subjects indicate that the majority of aluminum is bound to protein (>88%) with minor fractions as citrate complexes. These data are comparable with other speciation experiments with blood plasma indicating 90% of the aluminum was bound to plasma proteins.     

Trace metals in human lung as determined by neutron activation analysis of bronchoalveolar lavage

The possibility to use the bronchoalveolar lavage (BAL) in combination with analytical methods for trace metal analysis such as neutron activation analysis (NAA), inductively coupled plasma (ICP) and electrothermal atomic absorption spectroscopy (ETASS) for the determination of trace elements in the lung of living subjects has been investigated. In particular more than 30 elements have been determined: (1) in physiological solutions used for bronchopulmonary lavage (blank values) (2) in BALs of volunteer patients (unexposed subjects) (3) in BALs of occupational workers affected by pulmonary fibrosis as diagnosed by clinical methods (exposed subjects). Although the number of cases with metal exposure studied by NAA-BAL method is too limited to draw definitive conclusions the results suggest that the procedure can provide interesting qualitative information on metals which would be actually retained in the lung tissue. However, although the method may become of importance when integrated with clinical examinations further investigations are necessary to establish qualitative relations between trace metal levels determined in the BAL and the total elemental content of the lung tissue.     

Multi-element analysis of soils by computerized instrumental neutron activation analysis

The applicability of instrumental neutron activation analysis (INAA) for soils is described and demonstrated and its restrictions mentioned.     

Uranium in coral skeletons determined by epithermal neutron activation analysis

A simple and non-destructive method has been proposed for the routine determination of uranium by epithermal neutron activation analysis in coral skeletons. Using a cadmium capsule, about 0.1-0.2 g samples were irradiated for 6 hours in the Triga Mark II Reactor. Measurements of -ray (²³⁹Np via ²³⁹U) were performed with each sample and standard after cooling for about three days. Compared with a non-destructive thermal NAA, the present method was found to improve the sensitivity because it reduced the intense Compton background induced by ²⁴Na. We determined uranium in coral standards within 2% of analytical precision. The data obtained for the carbonate standards are mostly consistent with reported values. The present method could be usefully applied to determine uranium contents in fossil corals from the Funafuti Atoll in the Pacific. The distribution of uranium between seawater and coral skeletons is also discussed in order to understand the environmental media in which the coral grew.     

Total body sodium and chlorine in normal adults as determined by neutron activation analysis

Total body neutron activation analysis (TBNAA) has used to determine the absolute levels of total body sodium (TBNa) and total body chlorine (TBCl) in 81 normal adults. For the age span studied (30–90 years), the mean values of TBNa and TBCl remained relatively constant for males, but decreased slightly for females beyond sixty years of age. In order to reduce the variability in this cross-sectional study, the TBNa and TBCl values were normalized for body dimensions (weight, height, body surface area) as well as age and sex. In addition, TBNa was related to skeletal mass (total body calcium) and lean body mass (total body potassium). The quantity of body sodium in excess of the chlorine space was determined. This value, defined as sodium excess, was significantly correlated with total body calcium. The values for total body sodium, total body chlorine, and sodium excess obtained in the present study were compared with values previously reported in the literature.     

Determination of trace elements of Egyptian crops by neutron activation analysis

Multielemental neutron activation analysis was used for the determination of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W and Zn in African tea, and lady's fingers (Malvaceae Family), ginger (Zingiperaceae Family), canella bark (Laureceae Family), black pepper (Piperaceae Family), cucumber seeds and vegetable marrow seeds (Cucurbitaceae Family), tomatos seed (Solanaceae Family), safflower seeds (Compositae Family), jew's mallow seeds (Tiliaceae Family) and sesame (Pedaliaceae Family). Trace elements determination was made to the analysis of destructive (using super pure nitric acid and adsorbing the metal-APDC and metal-Dz complexes on activated charcoal) and nondestructive (dry seeds) samples. The method is simple, precise and sensitive for the determination of microamounts of the elements (ppm to ppb).     

Elemental abundances of lunar soils by neutron activation analysis

Résumé Pour déterminer 44 éléments dans des échantillons lunaires on a fait appel à l'analyse instrumentale par activation neutronique et à l'analyse par activation neutronique utilisant des séparations chimiques et la spectrométrie gamma à haute résolution. Si on utilise ces méthodes conjointement à la spectrométrie de masse à étincelle, on détermine plus de 56 éléments avec une certitude moyenne de 10%. On compare les résultats de l'analyse de sols lunaires rapportés par Apollo 11, 12, 14, 15 et 16 et par Luna 16.      

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.     

Determination of trace elements in Egyptian molasses by instrumental neutron activation analysis

Multielement neutron activation analysis has been applied to the determination of macro, micro and trace amounts of Al, Br, Ca, Cl, Co, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sc and V in molasses of Kom Ombo, Edfu, Armant, Naga Hammady and Abu Korkass cane sugar factories. The threshold element concentrations are acceptable and below the safety. Differences in element concentrations may be related to different botanic textures and structures, different compositions of sugar cane plants, corrosion of containers or changes in soil as a result of geochemical differentiation. The method is sensitive down to 0.038 ppm of V. The relative errors due to counting statistics are in the range of 0.2–11%.     

Determination of trace elements in Egyptian cane sugar by neutron activation analysis

Major, minor, trace and ultratrace concentrations of Ag, Al, As, Au, Ba, Be, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, K, La, Li, Lu, Mg, Mn, Na, Nb, Ni, P, Pb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Th, Ti, U, V, W and Zn in crude juice, principal juice, sirup juice (produced during the successive stages of sugar industry), sugar cane plant, molasses, deposits (produced as a result of the addition of Ca(OH)₂ and superphosphate and passage of SO₂ through juice), A-and B-sugar and soil samples have been determined by destructive and nondestructive instrumental neutron activation (INAA), atomic absorption spectrophotometric (AAS) and inductively coupled plasma-atomic emission spectrometric (ICP-AES) analyses. The results obtained by the methods applied are in excellent agreement. Concentrations of the elements are different. Variations in element concentrations in cance plants and in crude juice may be attributed to composition changes or different botanical structures; in mixed juice, sirup, molasse and deposits they may be due to chemical treatments or corrosion effects on containers, whereas in soil samples to geochemical and biogeochemical fractionation as a result of adsorption and uptake of trace elements by plants from surrounding soil solutions.     

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.     

The stability of trace metals suspensions in heavy crudes as determined by neutron activation analysis

The importance of trace elements in petroleum has increased, since the role of nonhydrocarbon components has been recognized in the elucidation of the mechanisms of migration and origin of crudes. On the other hand, knowledge of trace elements in petroleum is also important in the refining and processing of crudes. In developing different instrumental analytical techniques for trace analysis of crudes, little attention has been devoted to the scatter of data due to poor sampling and to the proper nature of the matrix. In the present paper the results of the determination of 17 trace elements including Co, Zn, Fe, V, Ni, Mo, Ba, Cs, Au, Br, Se, Sc, As, Mn, La, Eu and Cu are presented. A multielemental neutron activation analysis in a purely instrumental form was performed on a homogenized sample and the results are compared to those obtained on the same sample after a seven month period. The results clearly show that the crude loses its induced homogeneous nature and that a standard heavy crude can not be stocked for comparison purposes. For the heavy asphaltene fractions, results of the analysis of the same trace elements are presented and the possibility of its use as a standard is discussed.     

Elemental composition of dust in an iron foundry as determined by instrumental neutron activation analysis

In the workplace of an iron foundry total and respirable suspended particulate matter was daily collected with a network of stationary filtration systems, with Andersen cascade impactors and with personal samplers. The performances of the different sampling systems are evaluated. All samples were analysed by instrumental neutron activation analysis. More than 30 elements were determined. The composition of the particulate samples is compared to that of the major emission sources. For visualising and interpretation of the data computer programs for contour plotting, classification and clustering of the elements and the samples are applied. On the basis of their distribution and particle size the elements can be divided in a number of groups, for which easily determined elements are proposed as indicator elements. The results allow an estimate of the impact of the major emission sources on the air quality in the entire workroom. Suggestions for representative sampling techniques and locations are made.     

Determination of chromium in aquatic environment by substoichiometric thermal neutron activation analysis

Chromium has been determined in environmental samples. The method described here involves the irradiation of environmental samples and a g quantity of standard with thermal neutrons at the self-serve position in the CIRUS reactor, followed by dissolution of the sample and standard in the presence of a milligram amount of carrier. Both the sample and the standard are subjected to substoichiometric extraction under controlled experimental conditions with alizarin into cyclohexane. An aliquot of the organic phase was counted on a gamma-ray spectrometer. The concentration of Cr in water samples from Bombay and Karad City, and the accuracy, precision and sensitivity of the method are discussed.     

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.     

Some noble metals and copper content of italian meteorites as determined by destructive neutron activation analysis

Copper, iridium, platinum and gold content was determined in 15 italian chondritic meteorites by destructive neutron activation analysis. The chemical procedure involves few steps: sample dissolution, group separation of noble metals on inorganic adsorbers and gamma-ray spectrometry. Element content and atomic abundances (Si=10⁶ atoms) are presented and discussed. Precision and accuracy of the analytical method are given as well. Copper, platinum and gold content is within the reported ranges for ordinary chondrites, whereas the iridium content is located on the low side of reported values.     

Nutrient status of edible plantains (Musa spp) as determined by instrumental neutron activation analysis

Summary Instrumental neutron activation analysis (INAA) was to determine the nutrient status of six varieties of plantain. A total of 12 minerals were detected in both the pulp and the peel although their concentrations differed from variety to variety. Of these elements, only two (Mg and Cl) were classified, as macronutrients while seven (Cr, Zn, Se, Fe, Co, Mn, and Cu) were micronutrients essential for human life. The concentration of Cl, Mn and Cr in the edible pulp far exceeds the recommendations of the Subcommittee on Recommended Dietary Allowance (RDA). Aluminum, Br and Rb, which are neither classified as macro- nor micronutrients, were found in comparatively higher concentrations in the peel than is the pulp. The presence of seven micronutrients essential to human life in plantains makes it suitable for food, particularly in areas where micronutrient deficiencies may be prevalent.