Iodine transport

Single crystals of CuInS2 and the layered semiconductors were prepared by chemical transport reactions. Iodine transported n-type material had the best electronic properties among the CVT grown samples and was used here. 

A modification of this method was previously used for evaluation of thyrostatic drugs, andresponds to inhibition of the iodine transport mechanism in the thyroid gland. 

Figure 52-3 Formation and secretion of thyroid hormone. Iodine transport into the gland is inhibited by anions such as thiocyanate (SCN ), perchlorate (C 0 ), and pertechnetate (TcO ). The oxidation and organic binding of iodide to thyroglobuiin are blocked by thioureas, sulfonamides, and high concentrations of iodide. (Modified from Berger S, Quinn JLThyroid function. ln Tietz NW, ed. Fundamentals of clinical chemistry, 2nd ed. Philadelphia WB Saunders Co, 1976 585.)...

The erythrocytes of Co-treated anemic subjects have shorter life-spans. By binding to plasma proteins, cobalt also inhibits iodine transport and is goitrogenic (Herndon etal. 1980). In view of this evidence, the cobalt treatment of anemic subjects has been abandoned, and cobalt-containing anti-anemia iron preparations are no longer marketed in the USA. 

The input concentration and extent of sorption, as well as sorption kinetics, are seen to be correlated during iodine sorption and transport (Hu et al., 2005). In experiments on iodine transport in SRS surface soils at varying initial concentrations and residence times, iodate sorption was stronger, both at lower concentration and at longer residence time. The first-order desorption rate coefficients... 

Different iodine species exhibit very different sorption and transport behavior in geologic samples. Sorption of iodate is consistently greater than that of iodide, while the transport of organoiodine (exemplified by 4-iodoanUine in this study) is quite limited, and related to the amount of organic matter in the sample. The physical and chemical processes affecting iodine transport include iodate reduction, irreversible retention or mass loss, and rate-limited and nonlinear sorption of iodine. 

Cellular Iodine Transport Body Distribution of the Human Sodium Iodide Symporter... 

The available data from in vivo, as well as from in vitro, experiments clearly demonstrate that soy isoflavones act as inhibitors of TPO and thus may influence iodine incorporation in thyroid hormone biosynthesis. On the other hand, most of the cfinical trials, including our own, have shown only modest and transitory effects of soy isoflavones on circulating thyroid hormone levels. However, they may be important in the case of insufficient iodine supply. Besides thyroid hormone biosynthesis, soy isoflavones may influence other events involved in thyroid function, such as iodine transport, thyroid hormone deiodination, and signaling pathways. So far, the data available on these topics is scarce and more experiments addressing these issues are needed. 

Figure 101.2 Thyroid iodide transport and organification. A schematic of a thyroid follicular cell showing the key aspects of thyroid iodine transport and thyroid hormone synthesis. TSHR, TSH receptor NIS, sodium iodide symporter TPO, thyroid peroxidase Tg, thyroglobulin.

The Cs I atom ratios measured at the different sampling positions were in the range 2.0 to 3.5, roughly corresponding to the ratio of 3.0 which was calculated for the gap inventory of the failed fuel rods. These measured values strongly support the assumption of iodine transport in the primary circuit as Csl species. 

Gieseke, J. A., Flanigan, L. J., Collier, R. R, Denning, R. S. Steam generator tube mpture iodine transport mechanisms. Report NUREG/CR-3937 (1985)... 

The equilibrium partition state is not established instantaneously, not only because of its dependence on the disproportionation of HOI, but also because of the mechanisms of iodine transport in the liquid and gas phases. Under isothermal conditions, i. e. when both phases are at the same temperature, I2 molecules present in the water phase have to be transported by diffusion to the gas-liquid boundary layer from where they can pass over to the gas phase. When, however, the liquid phase shows a higher temperature than the atmosphere, diffusion transport will be supported by convection in the water phase. In the case of a boiling iodine solution the rate of I2 carry-over to the gas phase is greatly enhanced as a consequence of the vigorous convection within the solution. Usually, the time taken to reach the equilibrium state of iodine partitioning is not of significance for the situation inside... 

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