Assessment of concentration of radium, thorium, and
Assessment of concentration of radium, thorium, and potassium ... various parts of the world having higher amounts of mineral rocks [15–17]. Additionally, radon, a radioactive gas and one of the daughter products in the U-238 decay series, is both odourless and colourless. It can permeate the surrounding
Uptake of uranium and thorium by native and cultivated plants
Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially 'spiked' with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent.
Thorium Concentrations in Plants: A Review of World Data
Semantic Scholar extracted view of "Thorium Concentrations in Plants: A Review of World Data" by S. V. Fesenko et al.
TOXICOKINETICS, SUSCEPTIBLE POPULATIONS, …
A "critical" concentration of thorium in the extracellular space was found to be between 10 −7 and 10 −6 M; above this concentration, thorium hydrolyzes, becomes colloidal, and distributes primarily to organs of the reticuloendothelial system; below this concentration, thorium is distributed primarily to bone. The exposure levels in the ...
THORIUM (Th) CONCENTRATIONS IN SOIL OF TUZLA'S …
Thorium concentrations were analyzed in 12 9 soil samples, collected in the urban part of Tuzla. The thorium concentration is in the range from 4.1 to 15.6 ppm.
Transfer of uranium and thorium from soil to different parts …
The distribution of uranium and thorium in different parts of the studied plants showed the decreasing trend as root > leaf > stem > fruit (or seed). ... considering soil, climate and plant characteristics. From our studies it can be concluded that the uranium and thorium concentrations in the various studied plants depend on each species of ...
Uranium and thorium in urine of United States residents
We found uranium at detectable concentrations in 96.6% of the urine specimens and thorium in 39.6% of the specimens. The 95th percentile concenetration for uranium was 34.5 ng/L (parts per trillion); concentrations ranged up to 4080 ng/L. Thorium had a 95th percentile concentration of 3.09 ng/L; concentrations ranged up to 7.7 ng/L.
Age dependence of natural uranium and thorium concentrations …
The age dependence of the natural concentration of uranium and thorium in the skeleton was investigated using human vertebrae bone collected from two Canadian locations (Winnipeg, Manitoba, and Regina, Saskatchewan). The concentration of both radioelements in digested ashed bone samples was determin …
OR/17/001 The distribution of natural radioactivity in rocks
The concentration of thorium in metamorphic rocks is highly variable, and is dependent on the thorium content of the original parent igneous or sedimentary rock. Wedepohl (1978a) indicates that thorium concentration can range from <0.1 ppm in marble to >67 ppm in some high-grade feldspathic rocks. However, most metamorphic rocks probably …
Abundances of Uranium and Thorium Elements in Earth …
The geoneutrinos produced by the radioactive decays of uranium and thorium have been observed with the Kamioka Liquid-Scintillator Antineutrino Detector (KamLAND). ... has been updated by changing the U and Th concentrations in the upper continental crust by − 3.6% and −1.9%, respectively ... The central part of the detector …
Relative Contributions of Uranium, Thorium, and …
This will permit the average terrestrial concentrations of uranium and thorium to be 2 to 4.7 times higher than that observed in chondrites. The resulting ... ing in uranium concentration from 0.048 to 4.75 parts per million. The results on chondrites and achondrites represent the majority of published results. The uranium data is somewhat
GEOLOGY AND MINERALOGY OF THORIUM …
The optimum case is where the magma, low in calcium (alkalic) and high in aluminum (peraluminous), forms by melting of only small amounts (approximately 1%) of depleted …
Thorium anomaly on the lunar surface and its indicative …
FHT, and only medium Th concentrations in parts of SP AT ... This new thorium map also confirms that the eastern highlands have a relatively higher thorium concentration than the western highlands ...
Radioactive Elements in Coal and Fly Ash:
Thorium concentrations in coal fall within a similar 1–4 ppm range, compared to an average crustal abundance of approximately 10 ppm. Coals with more than 20 ppm thorium are extremely rare. During coal combustion most of the uranium, thorium, and their decay products are released from the original coal matrix and are distributed …
Thorium
Thorium is a radioactive element that occurs naturally in low concentrations (about 10 parts per million) in the earth's crust. It is about three times as abundant as uranium and …
Determination of thorium concentrations in soil and sand
Thorium along with its daughter products present in the soil is one of the major contributors to the external gamma dose in the environment. To establish the dose levels, quantification of thorium contents in soil samples is very important. As a part of pre-operational environmental radiological surveillance, a total of 23 soil and six sand …
Uranium and Thorium Resources
Thorium averages 12 parts per million in the earth's crust, and is the 39th most abundant of the 78 crustal elements. Soil commonly contains an average of 6 …
HEALTH EFFECTS
The estimated thorium concentrations ranged from 0.003 to 0.192 nCi/m 3 for a period of 1–33 years. In a follow-up study that also examined workers primarily involved in the production of incandescent gas mantles, ... 13 rad in the kidneys, and 60–620 rad in various parts of the lungs.
(PDF) RARE EARTH ELEMENT AND THORIUM ASSAYING IN PARTS …
RARE EARTH ELEMENT AND THORIUM ASSAYING IN PARTS OF THE EAST COAST, INDIA. ... (TREE) concentration with the Thorium concentration of the sample shows a positive correlation. Thus, prospecting of Thorium can be considered as a rapid field assay for estimating the concentration of REE in the area under study.
2 Natural Radioactivity and Radiation
Where uranium and thorium concentrations are high enough, rocks constitute ores to industrial societies. In the western United States, uranium ores have been extensively mined and milled to produce nuclear fuels. ... Like 238 U, 232 Th has markedly higher concentrations in some parts of the world. Because of its specific activity and low ...
Thorium Concentrations in Plants: A Review of World Data
Thorium concentration was determined in natural forage materials, thyme and barley (stern and kemel) in underlying substrate soil within, and around the thorium mine in Kizilcaoren-Eskisehir.
Thorium
Thorium, Periodic table Th, is present on Mars, however, its surface concentration seems to be lower than on Earth. Thorium can be used to produce fuel for nuclear reactors on Mars, including Liquid Fluoride Thorium Reactors, nuclear thermal propulsion and nuclear pulsed propulsion.
Thorium Concentrations in the Environment: A Review of the …
The concentration of thorium in the atmosphere depends on the meteorological conditions and the size, density, and the chemical form of thorium …
Thorium Removal, Recovery and Recycling: A Membrane …
The specific objectives of this work are to emphasize the existence of thorium in various materials used over time for common applications, the toxicity and bio-medical implications of thorium, the established technologies for obtaining thorium, the speciation of thorium in aqueous solutions, and the determination of thorium …
Thorium Concentrations in the Environment: A Review …
thorium concentrations on the environment assumes the availability of data on the background concentra-tions of thorium in soils, the aquatic environment, and surface air. The data on the concentrations of thorium in natural environment locations are relatively scarce, which makes it necessary to analyze and generalize the
Geoscience Wisconsin URANIUM AND THORIUM IN …
Whole-rock uranium and thorium concentrations in parts- per-million (ppm) were determined by the gamma spectrographic technique utilizing the method given by Adams and Gasparini (1970), and used by Meddaugh (1978), Anderson (1979), and Cook (1980) for this study. The laboratory facility consists of a testing chamber, gamma-ray sensor, ...
asteroid
The "very high" thorium concentration of SaU 169 is around 30 parts per million for the highest measurements (see table on page 6). That's only high in comparison to the bulk abundance of thorium in Earth's crust: thorium is typically extracted from monazite sands containing a couple percent to a couple tens of percent of thorium oxide.
Occurrence of uranium, thorium and rare earth elements in …
Thorium concentrations in the lithosphere range from 8 to 12 μg g −1. It is a weakly radioactive metal, similar to uranium, and occurs naturally in various minerals, soils, and waters . Thorium is not only critical for power generation, but also has applications in the production of alloys, arc welding, heat-resistant ceramics, ceramics ...
Nature, Sources, Resources, and Production of Thorium
In uranium ore deposits, thorium is concentrated in thorite and thorianite. In magmatic carbonate-enriched rocks (carbonatites), thorium is associated with rare earth elements (REE) in bastnaesite. However, the most important reserves of thorium occur …
Challenging the thorium-immobility paradigm | Scientific …
In this study, we determined the solubility of Th dioxide (ThO 2) in aqueous solutions as a function of sulfate concentration from 0.05 to 0.5 m Na 2 SO 4 at temperatures between 175 and 250 °C ...
Analysis of Thorium Concentration Anomalies on the Lunar …
China's Chang'E‐5 mission has collected lunar samples from a young mare plain with elevated thorium contents in the northeastern Oceanus Procellarum of the Moon.
POTENTIAL FOR HUMAN EXPOSURE
The concentration of total thorium in seawater ranges from 4×10 −5 to <0.5 μg/kg ( Greenberg and Kinston 1982; Sheppard 1980) and the world average concentration in …
Composition of hydroponic medium affects thorium uptake …
Negative correlation was found between putrescine concentration and thorium accumulation. Nevertheless, the most important factor influencing the accumulation of thorium was the absence of phosphate ions in a hydroponic medium that caused more than 10-fold increase of thorium uptake in all plant parts.
Southeast Asian dust flux reconstructed using accurately …
This study establishes a correlation between modern satellite-derived atmospheric dust concentration data and stalagmite thorium concentrations (from published records of stalagmites growing over the last 500 years), and subsequently applies this relationship to reconstruct Asian dust flux during the late Pleistocene using …
Gamma Rays, Meteorites, Lunar Samples, and the Composition …
The graph above shows thorium (Th) concentration (in parts per million, ppm) at the Apollo landing sites versus Th concentration as reported by the Lunar Prospector team. Feldspar-rich lunar meteorites are also used. The line is the best fit to the data and is used to correct the Prospector gamma ray data.