Neutron activation analysis of Cuban soils

Thirty elements were determined by INAA in Cuban soil samples collected in 17 zones from western regions of Cuba, which were affected by neuropathy epidemic in 1992. The presence of toxic elements was evaluated to provide data for the analysis of possible paths of intoxication through local agriculture product consumption. The results obtained for As, Th and U are compared with similar data reported on literature.     

Soil-plant relationi in Cuban sugar cane by instrumental neutron activation analysis (INAA)

This paper shows the result of soil-plant relation in samples from Cuban sugar canes of different soil types and cane varieties, using INAA from a thermal reactor. The behavior of minor and trace elements in sugar cane leaves is unifor and independent of sugar cane variety of type of soil. The soil-plant relation shows four principal groups of micro elements, according to their absorption by the plant.     

Neutron activation analysis of asbestos from Canada

Concentrations of Al, Au, Br, Ce, Cl, Co, Cr, Fe, K, La, Mg, Mn, Na, Ni, Sb, Sc, Sm, Srm and V were determined in 6 samples of asbestos from Canada. They were equal to (in ppm): Al 1660–3430; Au 0.03–0.04; Br 3.1–11.7; Ce 1.7–4.8; Cl 116–331; Co 35–83; Cr 200–2060; Fe 29300–42200; K 125–867; La 0.28–1.03; Mg 24–25.9%; Mn 418–545; Na 364–1610; Sb 0.65–1.46; Sc 3.73–5.57; Sm 0.09–0.3; Sr 26.7–41.4; V 8.4–14.3. Five toxic elements were found in asbestos; Cr, Mn, Ni, Sb and V.     

Instrumental neutron activation analysis of peloids from main Cuban spas

Journal of Radioanalytical and Nuclear Chemistry - Peloids from some Cuban spas (San Diego, Elguea, Santa Lucía, Cajío and Colony) have been studied using Instrumental Neutron Activation...     

Neutron activation analysis of indium

The extraction and extraction-chromatographic behavior of many elements in the tributylphosphate — HBr solution system has been studied. The investigation performed has made it possible to develop a simple technique for neutron activation determination of 22 impurity elements in high purity indium samples with detection limits from 0.1 ppm for Fe and Zr to 0.01 ppb for Na, Sc, Cu, As, La and W.     

Neutron activation analysis of radiopharmaceuticals

In order to understand the chemical form of soluble technetium in paddy soil and its availability to a rice plant, soil incubation and uptake experiments have been carried out using^95mTc as a tracer. The chemical form of the soluble Tc was observed by gel chromatography and found not to be pertechnetate, but rather to be associated with soluble organic matter. An uptake experiment with rice seedlings using nutrient solution showed that this Tc-organic matter complex was less available than pertechnetate.     

Neutron activation analysis of scandium

A neutron activation method is proposed for the determination of trace quantities of scandium, down to submicrogram level, in rocks, ores and meteorites. The sample and standard are irradiated intermittently for a total of 30 h, at a neutron flux of 5·10¹¹ n/cm²/sec; the radiochemical separation consists essentially of a one-step anion exchange. The induced γ-activity of ⁴⁰Sc, 85 days, isolated from the sample is measured and compared with that of a standard. The chemical yield averages 85% and there is a considerable saving of time in the radiochemical work. Results are quoted for the scandium contents of 2 standard rocks, cassiterite and several stony meteorites. Details of conflicting nuclear reactions are also given.     

Neutron activation analysis of soils

Résumé On décrit l'analyse de sols par activation neutronique au moyen de détecteur Ge(Li) à haute résolution pour la recherche de 31 éléments. Les éléments déterminés comprennent des métaux alcalins, des terres rares et des éléments de transition, la plupart d'entre eux sont utilisés, comme indices de différenciation géochimique et d'autres sont utilisés en tant que facteur de nutrition dans la physiologie des plantes. Quelques éléments comprenant Na, K, Rb, Cs, Ba, La, Ce, Sm, Eu, Th, Zr, Hf, Ta, Mn, Co, Fe, Sc, Cr, Sb, Ca, V, Al, Ti, Br et U ont été déterminés par spectrométrie gamma non-destructive, et d'autres Mo, W, Sr, Cu, Zn et Ga après une simple séparation radio chimique basée sur un échange d'ions et une extraction par solvant. On a employé l'activation dans les neutrons épithermique pour la recherche de l'U, utilisant des neutrons de réacteur. Les risques d'interférence dans les réactions et dans les spectres gamma, l'autoabsorption et les autres causes possibles d'erreur sont analysées et évaluées quand c'est possible. Les résultats sont donnés en temps que moyenne de plusieurs dosages. Dans tous les cas, on est parvenu à une grande précision.      

Neutron activation analysis of flints from the edwards formation

Procedures for instrumental neutron activation analysis have been developed and used on flint samples collected from the Edwards Formation in Texas. Each of the samples was analyzed for Mn, Ca, V, Al, Sc, Co, Fe, As, and K. USGS standard rocks AUG-1, GSP-1, and G-2 were also analyzed in order to test the reliability of this technique. Means and standard deviations of each element determined were calculated. The elemental values ranged from 0.03 ppm for scandium to 1500 ppm for aluminium. Based on relative elemental abundances, the rocks could be classified into two types of flint. This information suggests elemental inhomogeneity in the Edwards Formation.     

Neutron activation analysis of Urartian pottery from eastern Anatolia

The assessment of environmental pollution of the coastal areas of the Malaysian Peninsula was done by analyzing the contents of the heavy and trace elements in the bivalves blood clams (Anadara granosa) and green mussels (Perna viridis) and sediments at twenty-two sampling stations to look for prevailing trends. Heavy and trace elements analyzed in this study were As, Cd, Cr, Cu, Pb, Se and Zn. Two techniques, namely the neutron activation analysis (NAA) and atomic absorption spectrophotometry (AAS) were used in the quantitative determination of the heavy metals while Marine Sediment Reference Material (BCSS) and Lobster Hepatopancreas (TORT-1) provided the certified reference materials in the quality assurance control. The potential use of these bivalves as suitable bio-indicators was evaluated from correlation tests based on the concentrations of heavy and trace elements in the sediment-metals system to those in the bivalves.     

Neutron activation analysis of semiconductor silicon

The determination of impurities in semiconductor silicon by nondestructive and destructive NAA is described. To improve the detection limit, a multiple beta—single gamma detector assembly is used. It is shown that²⁴Na is also produced from silicon by a (n, αp) reaction with reactor neutrons. The cross-section with fission neutrons is 1.8·10⁻⁹ barn.     

Neutron activation analysis of lithium niobate

A radiochemical neutron activation analysis procedure for the determination of Ta, W, Ir, Pt, Au, Cu, Cr, Co and Zn in lithium niobate has been developed. The method involves a one-step removal of radioactive nuclides of Nb, Ta and W representing the dominating radioactivity of the irradiated sample. After irradiation, the sample is fused with inactive carriers and Na₂O₂ in a nickel crucible. The fused cake is dissolved in HCl–H₂O₂ and Nb, Ta and W are homogeneously precipitated. The impurities are separated by combinations of precipitation and ion-exchange separations for precise -ray measurements with an overall chemical yield of 70% to 90%. The results are discussed.     

Neutron activation analysis of chert artifacts from a Hopewell mound

Six artifacts from a Hopewell mound located near Mt. Vernon, Indiana, and 21 geologic specimens from three different chert sources in the Ohio River Valley were analyzed by instrumental neutron activation analysis. Principal components analysis and posterior classification of the artifacts on the basis of Mahalanobis distance calculated probabilities were used to determine the most probable source for each of the artifacts. This revised version was published online in July 2006 with corrections to the Cover Date.     

Neutron activation analysis of urinary stones

Human vesical, urethral and renal stones were analyzed for the trace elements Co, Cu, Mn, Zn and Mo. Statistical correlations between the elements determined were sought which would be of possible interest in further research on the initial causes of urinary stone formation in the human body. This research project was funded by a grant from the National Research Council of the Philippines. Read at the 40th Annual Convention of the Philippine Medical Association held in Manila, May 9, 1947.     

Automated determination of sugar in molasses

The importance of determining sugars in molasses is emphasized, and a short critical review of the methods available is presented. The difficulties and sources of errors in determining total sugar levels in molasses and sugar mixtures are discussed. A continuous automated procedure based on the hexacyanoferrate(III)/(II) redox reaction has been optimized by reducing the errors and interferences to a minimum. With this technique, sugar concentrations of 0–10 gl^-1 can be determined directly.     

Neutron activation analysis of Bawachi seeds

Seeds of (the plant) P. Corylifolia Linn (Bawachi) known for their therepeutic value in indigenous medicine have been analysed for Cu, As, Sb and Se by thermal neutron activation analysis involving substoichiometric extraction and precipitation technique. The amounts of Cu, As, Sb and Se per gram of seeds dried at 80°C are 16.0±1.1 μg, 0.90±0.4 μg, 12.1±0.6 μg and 4.0±0.2 μg respectively.     

Neutron activation analysis of arsenic species

Inorganic arsenic, MMA, DMA and arsenobetaine (As) were separated by the use of cation and anion exchange chromatography combined with neutron activation. Two complementary approaches were used: firstly, authentic, non-irradiated arsenic compounds, either singly or in mixtures, were separated and NAA of the fractions used as an element specific detection method. Secondly, the arsenic compounds were neutron irradiated under different conditions and for different times and the products separated and quantified. The⁷⁶As labeled species (mono-, di and trimethylated) were then additionally used to calibrate and improve the column separations. Using the separations developed, arsenic species in samples of shrimps and the standard reference material DORM-1 were determined, after an extraction step, using ion exchange chromatography followed by INAA of the fractions collected.     

Structural confirmation of oligosaccharides newly isolated from sugar beet molasses

ABSTRACT: BACKGROUND: Sugar beet molasses is a viscous by-product of the processing of sugar beets into sugar. The molasses is known to contain sucrose and raffinose, a typical trisaccharide, with a well-established structure. Although sugar beet molasses contains various other oligosaccharides as well, the structures of those oligosaccharides have not been examined in detail. The purpose of this study was isolation and structural confirmation of these other oligosaccharides found in sugar beet molasses. RESULTS: Four oligosaccharides were newly isolated from sugar beet molasses using high-performance liquid chromatography (HPLC) and carbon-Celite column chromatography. Structural confirmation of the saccharides was provided by methylation analysis, matrix-assisted laser desorption/ionaization time of flight mass spectrometry (MALDI-TOF-MS), and nuclear magnetic resonance (NMR) measurements. CONCLUSION: The following oligosaccharides were identified in sugar beet molasses: beta-D-galactopyranosyl-(1- > 6)-beta-D-fructofuranosyl-(2 <-> 1)-alpha-D-glucopyranoside (named beta-planteose), alpha-D-galactopyranosyl-(1- > 1)-beta-D-fructofuranosyl-(2 <-> 1)-alpha-D-glucopyranoside (named1-planteose), alpha-D-glucopyranosyl-(1- > 6)-alpha-D-glucopyranosyl-(1 <-> 2)-beta-D-fructofuranoside (theanderose), and beta-D-glucopyranosyl-(1- > 3)-alpha-D-glucopyranosyl-(1 <-> 2)-beta-D-fructofuranoside (laminaribiofructose). 1-planteose and laminaribiofructose were isolated from natural sources for the first time.