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Abstract  

In our biological investigations some trace elements have been determined by instrumental radioactivation analysis in organs of normal rats. The results of trace element distribution of Cr, Zn, Br, Sb, Fe, Co, Sc, Ag and Na in liver, spleen, brain, lung, kidney and heart of normal rats are presented in the paper.

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Abstract  

Two methods of concentration of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, In, Mo, Mn, Sb, Sc, Se, W and Zn from water have been elaborated. The trace elements are preconcentrated by coprecipitation with thionalide at pH 9, 1 and 0 or by sorption on ion exchange resin Dowex 1×2 loaded with 8-hydroxyquinoline-5-sulfonic acid at pH 7.

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Abstract  

Differently corroded glass-pieces of Roman, mediaeval and baroque origin were inspected by light and electron microscopes and afterwards several impurities determined semi-quantitatively in the glass matrix and corrosion layers by neutron activation analysis. Sodium glasses contained in general less trace elements and proved to be more resistant against corrosion and devitrification than potassium glasses which showed a high content of foreign elements. In the intermediate layers between glass and corrosion products not only an increased number of impurities was detected, but also an enrichment factor of about 20 in comparison to the glass matrix was found. According to the observed relation between content of trace elements and degree of corrosion, impurities seem to deteriorate the long term stability of a glass matrix.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: I. O. Abugassa, S. O. Abugassa, Y. S. Khrbish, A. T. Bashir, K. Doubali, and N. Ben Faid

Summary  

The trace elements composition of gallbladder stones samples of the types cholesterol, pigment and mixed stones in addition to bile have been investigated by k 0-instrumental neutron activation analysis (k 0-INAA). The samples were obtained from several individuals of adult subjects of the Libyan population who undergone open surgery of gallbladder (cholecystectomy) at Al-khadra University Hospital in Tripoli. The samples were lyophilized, irradiated together with Au wire and Zr foil, which serve as flux ratio monitor and a parameter at TNRC. Concentrations of 24 elements in gallstone and 23 elements in bile were determined. The levels of the trace elements in the various samples investigated are measured and discussed. The reliability of the analysis was checked with several biological standard reference materials.

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Summary  

The International Atomic Energy Agency (IAEA) has, for many years, supported research on human dietary intakes of trace elements taking advantage, for analysis, of the possibilities offered by nuclear techniques, particularly neutron activation analysis (NAA). This paper summarizes the results obtained from studies in more than 20 countries in which special emphasis was placed on the application of reliable methodologies (written protocols, special equipment, analytical quality control, etc.). Considerable variation was observed among dietary intakes of essential minor and trace elements though most elements showed a pattern of adequate nutrition in most countries. However, for some elements such as calcium, iodine, iron and zinc, the intakes in many countries were lower than the dietary requirements.

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Abstract  

The use of high-resolution Ge(Li) detectors in non-destructive instrumental neutron activation analysis (INAA) of mineral materials makes possible the simultaneous determination of a number of trace elements. In routine applications of INAA the use of a multi-element standard (MES) has proved to have advantages over a set of standards for each determined element. An MES has been prepared containing 8 trace elements mixed in a suitable proportion and giving, after neutron activation, long-lived γ-emitters, the γ-ray lines of which regularly occur in the γ-ray spectra of silicate mineral materials. This method has been used in the determination of Sc, Cr, Co, Rb. Cs, Eu, Hf and Th in samples of standard rocks and moldavites.

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Abstract  

The concentrations of REE and other trace elements have been determined in samples of Antarctica by Instrumental Neutron Activation Analysis (INAA). The samples were collected from the West Lake area near Great Wall Station. The samples include sediment, residual plants, rock and soil taken from the bottom of the lake to 3.4 m deep. The amounts of samples were very rare. In order to get more information, reactor NAA using both short and long irradiations with K0 standardization has been adopted. Nine rare-earth elements (REE) namely La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, and Lu as well as other trace elements (As, Au, Ba, Br, Co, Cr, Hf, Sc, Se, Th, V, Zn) have been determined. The concentrations and distribution patterns of REE in the samples have been given.

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Abstract  

In order to complete having data base of elemental assessment of the east coast of Peninsular Malaysia marine sediments along the South China Sea coasts, trace elements are analyzed and their distribution in marine sediments is undertaken. The present study is done parallel with pervious study on elemental assessment of heavy metals, rare earth elements and actinides in the marine sediments of the east coast of Peninsular Malaysia. Thirty surface sediment samples were collected in this area, including regions of Kelantan, Terengganu, Pahang, Rompin and Johor Baharu. Multielemental analysis was carried out by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectroscopy. In both cases methodology validation was performed by certified reference material analyses. For the surface elemental distributions the enrichment factor values, average I geo and mC d values indicate that the trace elements of the surface sediments are uncontaminated in all sampling stations that are consistent with previous studies results of heavy metals, rare earth elements and actinides.

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Abstract  

A number of essential trace elements play a major role in various metabolic pathways and in many diseases like autoimmune, neurological and psychiatric. This study is undertaken with an aim to evaluate the levels of different trace elements in the scalp hair samples of patients suffering from alcohol induced psychosis by particle induced X-ray emission technique (PIXE). It is observed that Fe (p < 0.0005), Cu (p < 0.001) are significantly higher in the hair samples of alcohol induced psychosis patients compared to those in normals while concentrations of Mn (p < 0.005) and Zn (p < 0.0001) are lower. The concentrations of Co and Ni in the hair samples are found to be in consonance with the concentrations in the normals.

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Abstract  

This study comprises Tertiary sediments (clays, silts, and fine clayey sands) from the unsaturated zone of the Experimental Station in the University of São Paulo, taken from a nine meters depth profile; ten samples were separated in bulk and <53 m fractions. Chemical composition was determined by INAA to ascertain the distribution of trace elements throughout the sediment deposition, and to establish the background parameters, useful for mobilization studies of such elements after industrial waste disposal.

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