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Abstract  

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.

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Abstract  

Industrial units play a significant role in atmospheric pollution. Industrial exhausts deteriorate the atmospheric quality causing unhygienic environment for the people working in the vicinity. This work presents a study of the longitudinal distribution of trace elements of the Sheikhupura industrial area. Three kinds of distribution patterns were observed and are discussed in detail. The results are based on the neutron activation analysis of 16 trace elements.

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Abstract  

Some trace elements in samples from the aluminium industry (Aluminium Kombinat, Titograd, Yugoslavia) were determined by instrumental neutron activation analysis. Samples characteristic for alumina production (bauxite, red sludge), reduction cell components (alumina, anode, AlF3, cryolite) and aluminium produced (purity 99.5–99.7%) have been analyzed. 10 trace elements were determined under a given set of working conditions and followed through the routine production.

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Abstract  

A radioisotope-excited energy-dispersive X-ray fluorescence system has been constructed and used for the analysis of blood samples for trace elements. The possibility of determination of trace elements in blood by X-ray fluorescence based on comparison with standard reference materials has been outlined and the applicability of the method demonstrated by the analysis of blood samples. The method enables fast, non-destructive direct analyses to be carried out without lengthy sample pretreatment on a routine basis.

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Abstract  

Tea has been one of the most popular simulating beverages which is both heavily produced and consumed in Taiwan. The determination of minor or trace elements in drinking tea and tea leaves is therefore important for estimating the daily intake of Taiwanese considered as a safety indicator. In order to accurately and precisely determine the concentrations of trace elements in samples, several analytical methods such as AAS, NAA and ICP-AES are suggested. This paper attempts to utilize all three methods to determine the concentrations of minor or trace elements in different types of tea leaves and the extracts percolated from them. The influence of fermentation processes on the concentration levels of minor or trace elements in tea samples is investigated. Because only free metal ions are bioavailable for the human body, it is necessary to determine their concentrations in drinking tea. The dissolution of trace elements in drinking tea is therefore studied by simulating the common Chinese style of tea percolation. Concentrations of thirteen elements including Zn, Mn, Ca, Cu, Ni, Al, K, Mg, Cd, Pb, Na, Co and Sc are determined.

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Abstract  

In Algeria, bread is the staple food, produced in different kinds from local and imported wheat. Most of it is not subjected to micro-elemental analysis. The objective of this study is to determine quantitatively the traces elements in samples wheat grains produced locally from different cultivated provinces in Algeria. Trace elements (Co, Cr, Cs, Fe, Rb, Sc, Se and Zr) were determined using neutron activation analysis. The results show that the contents of the traces elements in the studied samples were within the safety baseline of all the assayed elements recommended by WHO/FAO except for cobalt in El Harrach province. The analytical results showed that chromium was undetectable in all samples except for Constantine, Ain Mlila and Setif provinces. However zirconium content in a few samples exceeded the permissible level.

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Abstract  

Instrumental neutron activation analysis was applied to the determination of trace elements in a Na-bentonitic clay. The irradiation was done in the Triga Mark II type reactor of ITU Nuclear Energy Institute. The sample was irradiated in two steps for short- and long- lived isotopes. After irradiation, spectra were taken using a germanium detector, multichannel analyzer Canberra System 100 and a fitting program called Sampo 90. The spectra of short-lived isotopes were analyzed to determine Al, Mg, Na, K, Ca, Ti elements and Mn, V trace elements. The spectra of long-lived isotopes were analyzed to determine Sc, Br, Sb, Cs, La, Ce, Sm, Yb, Hf, Pa, Np trace elements.

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Abstract  

Trace elements play an important role in the metabolism of the human body. Some of the trace elements are essential, whereas others are toxic and even carcinogenic. Cigarette smoke contains many of these hazardous trace elements. Tobacco samples have been analyzed by the authors for their trace element contents and the results have been reported earlier. This paper presents results on the trace element content analyzed in cigarette smoke using an automatic smoking machine developed in this laboratory to simulate actual smoking pattern. The trace element levels in the total particulate matter samples of the cigarette smoke collected on filter papers were measured and compared with those of cigarette smoke condensate reported in the literature. Both methods of collection give comparable results.

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Abstract  

Considerable interest in determining levels of trace elements in foods has occurred in the last twenty years. This interest comes from studies attempting to determine the role that elements play in the flavor and in the toxicology of food. Radiochemical methods, like instrumental neutron activation analysis (INAA), are common techniques used to determine dietary trace levels of various elements. A summary of other methods are also referenced in this updated review of past, present, and future uses of radiochemical methods to determine trace elements in food.

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Abstract  

Instrumental neutron activation analysis was performed on scalp hair and fingernail samples collected randomly from a group of heavily exposed healthy male industrial workers living in the cities of Hamilton and Toronto (Ont.), Canada. The concentrations of trace elements (Ag, Au, Br, Cd, Co, Cr, Cs, Fe, Hg, Lu, Mn, Mo, Rb, Ru and T3) were evaluated and compared for scalp hair and fingernails. Various trace elements show similar variations in the two kinds of samples. The results have also been compared with those for normal subjects from USA (scalp hair) and Canada (fingernails).

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