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Abstract  

The ultimate purpose of all studies on environmental contamination is to protect human life; as a consequence the knowledge of the trace element pathways from environment to man is of paramount importance because it allows the assessment of a clear relationship between any environmental contamination and its effects on man. To this extent two different kinds of environmental studies will be described in this paper: (a) Studies of the geographic variations on the whole national territory of the natural levels of trace elements in water, food and some human tissues. (b) Studies of selected areas where a critical population group is exposed to abnormal levels of some trace elements. The main trace elements considered are: Co, Cr, Cs, Fe, Hg, Ni, Rb, Sb, Sc, Se and Zn; all the measurements were performed by means of non-destructive neutron activation analysis.

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Abstract  

Thermal neutron activation analysis and a large-volume high-resolution Ge(Li) gammaray spectrometer, connected on-line to a DEC PDP 8/L computer, have been used to measure the concentrations of Na, Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, W and Hg in some Italian subsurface water samples. The instrumental method requires neither a chemical separation technique nor a pre- or post-concentration of the trace elements to be detected. As a consequence, this method eliminates many inherent errors associated with chemical determinations. The technique is sensitive, precise and particularly suitable for routine analysis of many trace elements at both natural and pollution levels in water samples. The interferences due to fast neutron (n, p) and (n, α) reactions are not appreciable, with the only exception of the54Fe(n, p)54Mn and58Ni(n, p)58Co reactions. Losses of volatile, elements, e. g. As, Br and Hg, during irradiation proved to be negligible.

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Abstract  

The content of the following trace elements, Ag, Co, Cr, Cs, Fe, Hg, Rb, Sb, Se and Zn has been evaluated in the diets, excretion (urines and feces), blood and hair samples taken from different groups of subjects. Each population group is composed by five or more individuals selected in order to be representative of the adult population living in a well defined community. Some communities, with different socio-economical living habits, and displaced in different regions of Italy, have been considered in order to detect the variability, if any, of the trace element distribution among the Italian population. The data obtained seem to show a reasonable uniformity of the average trace element daily intakes in different regions of Italy. Beside the individual variability, very significant differences among the groups studied have not been found, as the trace element contents in excreta, blood and hair samples are concerned. All data are compared with similar data referred to population living in other countries.

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Abstract  

A report is given on the various research activities concerning radioanalytical chemistry performed in the following fields; (a) radiochemistry; (b) non-nuclear methods; (c) instrumental neutron activation analysis; (d) computer analysis of γ-ray spectra. All these activities are carried on in the frame of two surveys extended to the whole Italian territory: the first one on the radioactive environmental contamination both of natural and of artificial origin; the second one on a number of non-radioactive trace elements, with a particular emphasis upon their presence, as contaminants, in the food-chain and upon their uptake by man.

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Journal of Thermal Analysis and Calorimetry
Authors: Francisco J. N. Maia, Viviane G. Ribeiro, Claudenilson S. Clemente, Diego Lomonaco, Pedro H. M. Vasconcelos, and Selma E. Mazzetto

Abstract

In this study, the thermo-oxidative stability of two new phosphorylated derivatives of cardol, a compound from the cashew (Anacardium occidentale L.) industry waste CNSL (cashew nutshell liquid), were evaluated. The antioxidant capacity of these new molecules upon two mineral oils, NH10 and NH20 were also studied by thermogravimetric analysis (TG/DTG), observing the onset and offset temperatures variation. The results showed that both MP and DP Cardol increased considerably the onset and offset temperatures of NH10 and NH20 oils.

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