A solid chelating material, 1-(2-pyridy1azo)-2-naphthol (PAN) supported on naphthalene provides a rapid and highly selective means of preconcentration of uranium from aqueous solution. Uranium is quantitatively retained on this adsorbent in the pH range 9.8-10.7 with a flow rate of 1 ml min . The metal complex was desorbed with 10 ml of 2 M hydrochloric acid and uranium is determined by d...

Studies of the distribution of uranium in animal tissues (1, 2) have shown that a large proportion of the injected dose accumulates initially in the bone and kidney. 40 days after injection, however, bone is the only tissue which has retained significant quantities of the metal (2). Because of the importance of bone as a storage site for uranium, more specific information has been obtained conc...

background: measurement of back ground concentration of uranium in drinking water is very important for many reasons, specially, for human health. the uranium concentration in drinking water in many counties is a matter of concern for clinical and radioactive poisoning. materials and methods: the uranium concentration in drinking water is determined using laser flourimatric uranium analyzer. fo...

Uranium L(III)-edge X-ray absorption spectroscopy is often used to probe the oxidation state and coordination of uranium in environmental samples, and micrometre-sized beams can be used to spatially map the distribution of uranium relative to other elements. Here a variety of uranium-containing environmental samples are analyzed at both microbeam and larger beam sizes to determine whether reoxi...

In experiments on mice, rabbits, and piglets the distribution of uranium was studied at different times after exposure. Uranium was administered by inhalation (mice) and through the skin (rabbits and piglets). These investigations show that the uptakes of uranium in different organs of the three species are highly dependent on the amounts administered. There seems to be a saturation effect in t...

Background: Measurement of back ground concentration of uranium in drinking water is very important for many reasons, specially, for human health. The uranium concentration in drinking water in many counties is a matter of concern for clinical and radioactive poisoning. Materials and Methods: The uranium concentration in drinking water is determined using laser flourimatric uranium analyzer. Fo...

In order to identify radon-prone areas and evaluate radon risk level, a soil gas radon survey combined with gamma-ray spectrometry measurements was carried out in Shenzhen City, south China. Meanwhile, the statistical analysis was applied to evaluate the distribution of measured results. This paper presents the methodology of the radon risk assessment. A radon risk map was accomplished based on...

Simulation studies present an important statistical tool to investigate the performance, properties and adequacy of statistical models in pre-specified situations. One of the most important statistical models in medical research is the proportional hazards model of Cox. In this paper, techniques to generate survival times for simulation studies regarding Cox proportional hazards models are pres...