Iodine

About: Iodine is a research topic. Over the lifetime, 8936 publications have been published within this topic receiving 139981 citations. The topic is also known as: I & element 53.

Boosting the Iodine Adsorption and Radioresistance of Th-UiO-66 MOFs via Aromatic Substitution.

Abstract: Effective capture of radioactive iodine is of paramount importance for the safe and long-term storage of fission products in the nuclear fuel cycle. Herein, a series of functionalized Th-UiO-66 MOFs was employed as a model to investigate the effects of substituents on iodine adsorption in both solution and vapor states. Sorption studies revealed that the electro-donating amino group exhibits the most positive role on increasing the removal rate of iodine from cyclohexane and the uptake capacity of iodine vapor. Particularly, the disubstituted Th-UiO-66-(NH2 )2 can effectively remove 91.9 % of iodine (300 mg L-1 ) from cyclohexane and capture 969 mg g-1 iodine vapor, significantly higher than 59.6 % and 334 mg g-1 of untagged Th-UiO-66, respectively. In addition, the substituent effect on the radiolytic stability of MOFs was for the first time investigated, leading to the unearthing of one of the most radioresistant MOFs Th-UiO-66-NH2 reported to date.

Hypertrophy and hyperplasia during goitre growth and involution in rats--separate bioeffects of TSH and iodine.

Abstract: Goitre growth was investigated in rats receiving a low iodine diet (less than 0.1 microgram iodine/g) and either 1 g/l KClO4 or 1 g/l propylthiouracil (PTU), or a combination of KClO4 or PTU with 50.82 nmol/1 T3 in tap water for 3 weeks. To investigate goitre involution, rats with iodine-deficient goitres were treated for 3 weeks either with T3 (0.5 microgram T3/day = 0.768 nmol/day), iodide (0.5 or 2.7 micrograms KI/day) or a combination of T3 with both iodide doses. Histology together with total DNA distinguished between hypertrophy and hyperplasia of the gland. During goitre growth there was highly significant correlation between goitre weight and TSH serum level (r = 0.93, P less than 0.001). Thyroid total DNA, however, was only weakly correlated to TSH but was inversely related to the degree of iodine deficiency. During goitre regression, TSH levels were normalized, histological signs of hypertrophy had disappeared, and thyroid weight was nearly normalized in all therapy groups. Total DNA, however, was normalized only with 2.7 micrograms KI/day (95 +/- 18 micrograms DNA/gland), and still elevated in all other groups. The highest DNA levels were found under T3 therapy (143 +/- 21 micrograms DNA/gland) and under 0.5 microgram KI/day (161 +/- 19 micrograms DNA/gland). Reduction of total DNA was independent of TSH, but followed replenishment of the iodine content of the glands. We conclude that TSH mainly induces hypertrophy, whereas thyroid hyperplasia is mainly regulated by the intracellular iodine content.

Electrochemistry of Iodide in Propylene Carbonate I . Cyclic Voltammetry Monitored by Optical Spectroscopy

Abstract: The electrochemistry of iodide in propylene carbonate (PC) was investigated using cyclic voltammetry. In an anodic sweep, iodide is oxidized sequentially to triiodide and then to iodine according to 3I/sup -/ ..-->.. I/sub 3//sup -/ + 2e/sup -/ (I) 2I/sub 3//sup -/ ..-->.. 3I/sub 2/ + 2e/sup -/ (II). This mechanism was confirmed using UV-visible spectroscopy in conjunction with cyclic voltammetry experiments at a thin gold mesh electrode. Potential step experiments were used to measure a diffusion coefficient of 4 X 10/sup -6/ cm/sup 2//s for iodide in a KAsF/sub 6/ PC electrolyte.