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Trace element behavior types

Nowadays the one of the leading cause of death in industrial country is Heart Failure (HF). Under the pathological conditions (e.g., Ischemic Heart Disease (IHD)) the changes in the enzymes activity and ultrastructure of tissue were obtained. The behavior of trace elements may reflect the activity of different types of enzymes. Pathological changes affects only small area of tissue, hence the amount of samples is strictly limited. Thereby, nondestructive multielemental method SRXRF allow to perfonu the analysis of mass samples in a few milligrams, to save the samples, to investigate the elemental distribution on the sample area. [Pg.353]

Group 3 elements which are not mostly vaporized in the boiler (1423 K) V, Cr, Mn, Co, Ni Referring to the classification, we investigated the temperature dependency of release of trace metals in coal combustion. We already reported the behavior of these three types of elements during high temperature coal processing and reported elsewhere . So in this paper, we investigated the effect of atmosphere for the emission behavior of trace elements. [Pg.573]

Over the past decade several studies ascertained the content of several trace elements, primarily Cd, in rice cultivated in different countries (see, e.g., [31-40]). A recent study reported a total As concentration in various types of Italian rice as ranging from 80 to 280 ng g-1, and compared these figures with those obtained for other countries [41]. The ability of As to accumulate in rice can be ascribed to the fact that As is similar to P in terms of biogeochemical behavior [8, 42-44],... [Pg.391]

Conservative type Some of the trace elements such as U, W, and Re form stable ionic species, UOiiCOs) , WOl , and ReOj in sea water. Hence, their oceanic behavior is conservative (follow salinity) and their mean residence times in the ocean are generally long (e.g., >10 years). There is no significant variation in their concentration between different oceanic basins. [Pg.10]

Commercial elemental sulfur is usually of bright-yellow color at 20 °C [36]. Pure orthorhombic a-Ss is, however, of greenish-yellow color at 20 °C but totally colorless at 77 K while commercial sulfur often remains pale-yellow at this temperature [59]. The reasons for this different behavior are twofold. Commercial samples are never pure Ss but besides traces of organic impurities they always contain Sy in concentrations of between 0.1 and 0.5% [59]. Sulfur found as a mineral in Nature sometimes also contains Sy but in addition traces of selenium are quite often present (up to 680 ppm Se, probably as SySe molecules) [60]. These minor components influence the color of the samples at ambient and low temperatures in the sense that a more orange-type of yellow ( egg-yellow ) is recognized. [Pg.41]

Radiochemical analyses of PWR primary coolant show that the major fraction of the neptunium and plutonium traces in the coolant is usually associated with the corrosion product suspended solids and that it can be removed from the coolant by filtering. Only in cases of very low corrosion product concentrations in the coolant were significant proportions of the transuranium elements observed to be present in a dissolved (i. e. non-filtrable) form. As yet, it is not known whether mixed oxide formation between magnetite-type oxides and these elements is responsible for this behavior or whether the actinide traces are adsorbed by van de Waals forces onto the large surface areas of the finely dispersed suspended solids. Under constantload operation conditions and as long as no additional fuel rod failures occur, the activity ratio Pu Co in the corrosion products remains virtually constant over time, thus indicating a similar behavior of these different elements in the coolant. [Pg.225]


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See also in sourсe #XX -- [ Pg.64 ]




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Element types

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