In the 1930s and 1940s the radioactive contrast material colloidal thorium dioxide (Thorotrast) was frequently used in radiographic examinations. The agent was used mainly for angiography and to a lesser extent for myelography, ventriculography, pyelography, and hepatolienography. The late clinical complications and conventional radiographic manifestations of thorium administration have been we...

heavy water plus neutral current additive to an activity level of one decay per day per tonne ofD^O (DDT) for the thorium chain and(5(TpDTs for the uranium chain. /O jL^ It is equally important to be able to monitor these activity levels, by some form of ^f radioactive assay. From the point of view of purification the critical isotopes are 2 y year ^Th in the thorium chain (see Fig. 1) and 1600...

Lunar Prospector gamma-ray spectrometer spectra along with counting rate maps of thorium, potassium, and iron delineate large compositional variations over the lunar surface. Thorium and potassium are highly concentrated in and around the nearside western maria and less so in the South Pole-Aitken basin. Counting rate maps of iron gamma-rays show a surface iron distribution that is in general a...

Sir, Thorium X, a natural isotope of radium, was the main radiotherapeutic modality for treating vascular lesions of the skin including port-wine stain (PWS) available to dermatologists during the 1930s to 1950s. It disappeared from dermatological practice around the 1960s, and the chapter on thorium X was considered closed (1, 2). However, occasionally long-term sequelae have been described (2...

Using density functional theory (DFT) calculations, we have systematically investigated the thermodynamic properties and structural stabilities of thorium dioxide (ThO(2)). Based on the calculated phonon dispersion curves, we have calculated the thermal expansion coefficient, bulk modulus, and heat capacities at different temperatures for ThO(2) under the quasi-harmonic approximation. All the r...

The first step in investigation of thorium fuel is evaluation of the results obtained from the spectral code for this type of fuel. The benchmark summarized by IAEA in 2003 was used for partial validation of the code HELIOS 1.9. The benchmark was focused on a comparison of the methods and basic nuclear data. Acceptable results of benchmark comparison allowed examining and comparing different ad...

In this study, the production technology of rare-earth oxides from Eskişehir-Beylikova complex ore that contains barite, fluorite, elements, and thorium were investigated. processes can be used in thorium-free mixed rare earth tested. Roasting, leaching, solvent extraction precipitation methods respectively. Roasting temperature roasting duration determined as 600 °C 1 hour, The optimum leachin...

Thorotrast (a colloidal suspension of thorium dioxide) injected into the dorsal lymph sac of the common frog, Rana temporaria, can be shown by radiological methods to pass through the anterior lymph hearts and so into the blood system. From the blood the thorotrast is removed, as in mammals, by cells of the reticulo-endothelial system and by macrophages, the sites of greatest activity being the...

Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations ...