An efficient laboratory experiment has been developed for undergraduate students to conduct hydrogen-deuterium (H-D) exchange of resorcinol by electrophilic aromatic substitution using D2O and a catalytic amount of H2SO4. The resulting labeled product is characterized by 1H NMR. Students also visualize a significant kinetic isotope effect (kH/kD ≈ 3 to 4) by adding iodine tincture to solutions ...

The irradiation of a thorium target by light charged particles (protons and deuterons) leads to the production of several isotopes of medical interest. Direct nuclear reaction allows the production of Protactinium-230 which decays to Uranium-230 the mother nucleus of Thorium-226, a promising isotope for alpha radionuclide therapy. The fission of Thorium-232 produces fragments of interest like M...

Internal-mirror 543-nm He-20Ne and He-22Ne lasers are frequency-stabilized to the Lamb-dip of their tuning curves. Frequency stability of 2×10−11 and frequency resettability of 4×10−9 (or 2 MHz) are achieved. The absolute frequencies of the two lasers are determined by frequencycomparing with an iodine-stabilized 543-nm laser. The isotope shift between 20Ne and 22Ne is measured to one order of ...

It was in May, 1938 that Hertz et al. (1) published the first report on biological studies with a radioactive isotope of iodine. By today's standards these first studies were done under the least favorable conditions with an isotope whose half life of 25 minutes limited the studies that could be done. Notwithstanding the limitations put on these investigators they not only reaffirmed certain pr...

Isotope dilution mass spectrometry (IDMS) is used extensively at NBS in the certification of elemental concentrations in Standard Reference Materials. It is regarded at NBS as a "definitive method," that is, a method of proven high accuracy. Since the theme of this symposium is accuracy in trace element analysis, it is appropriate to review the role IDMS plays in accurate inorganic analysis. Th...

Dual-isotope myocardial SPECT in a female patient with idiopathic myocarditis showed completely inverse images in Tl-201 and I-123 MIBG SPECT. In the dual-isotope SPECT performed 13 days after her admission, Tl-201 SPECT images showed reduced accumulation in the apex and normal accumulation in the other regions, whereas the corresponding I-123 MIBG SPECT images showed normal findings in the ape...

iodine is essential element in thyroid hormones synthesis and normal growth and development of the brain. milk and iodine concentrations can be appropriate indicator of body iodine status; in this study, we evaluated the concentrations of urine and milk iodine in newborns and their mothers.in a cross-sectional study conducted in 2013, urine and milk iodine in 106 neonates and their mothers refe...

Thyroxine in the thyroid gland is considered to be firmly built into the protein molecule, thyroglobulin (1). Only after the gland is hydrolyzed with fairly strong alkali does its thyroxine become readily extractable with butyl alcohol. The iodine which circulates in plasma, on the other hand, can be almost completely extracted with butyl alcohol without previous hydrolysis (2). Considerable ev...

iodine deficiency is the most important preventable cause of mental deficiency. the aim of this study was to specify the phase during fetal and postnatal development when iodine supplementation would have optimum effect on the prevention of brain damage. materials and methods forty schoolchildren aged 7-13 years, from the previously iodine deficient villages of kiga and randan, were divided int...