naturally occurring radionuclides have different amount of activity concentration for 226 ra, 232 th and 40 k in building materials. in this study, natural radioactivity has been measured for bricks used in tehran. for this work, 9 samples of three types of bricks, clay brick (cb), making the facade brick (mfb) and firebrick (fb) has been selected from different regions and factories in tehran....

The German Meteorological Service (DWD) is charged with tasks of radiation protection by the Law of the Deutscher Wetterdienst (1955, 1998), the Precautionary Radiation Protection Act (1986) and the Radiation Protection Ordinance (2001). Since 1955 the DWD is responsible for the surveillance of radioactivity in the atmosphere realized by measuring the radioactivity as well as analyzing the mete...

BACKGROUND Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing a safe environment for radiation workers but also to ensure accuracy of dispensed radioactivity and an efficient workflow. For this purpose, we have designed ARAS, an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting ra...

A rapid procedure for measuring the specific radioactivity of phenylalanine in tissues was developed. This facilitates the accurate determination of rates of protein synthesis in a wide range of tissues by injection of 150 mumol of L-[4-(3)H]phenylalanine/100 g body wt. The large dose of amino acid results in a rapid rise in specific radioactivity of free phenylalanine in tissues to values clos...

In previous studies, we have shown that a relatively large amount of low density lipoproteins is released into the perfusate during isolated pig liver perfusion. The present studies were done to determine the source of these lipoproteins. Breakdown of the very low density lipoproteins to low density lipoproteins by the perfusion apparatus or by hepatic catabolism was excluded by adding 125I ver...

Crystalline Ponceau MX (Ponceau R, disodium 1-(2, 4-xylylazo)-2-naphthol-3 , 6-disulphonate) labeled with 35S was synthesized from radioactive H2*SO4, β-naphthol and mxylidine, and a solution of the compound having the radioactivity of 5×105cpm/ml by gas flow counter was prepared. Then this solution was given to experimental animals to investigate the distribution and excretion of the dyestuff ...

UNLABELLED 18F-FCWAY (18F-trans-4-fluoro-N-(2-[4-(2-methoxyphenyl) piperazin-1-yl)ethyl]-N-(2-pyridyl)cyclohexanecarboxamide) is useful in clinical research with PET for measuring serotonin 1A (5-HT1A) receptor densities in brain regions of human subjects but has significant bone uptake of radioactivity due to defluorination. The uptake of radioactivity in skull compromises the accuracy of meas...