Uranium determination

In addition to meeting the foregoing requirements, a good internal standard will be easy to add uniformly and precisely, and (preferably) no appreciable amount of the element St (free or combined) will be present in the sample before the addition. Cope29 provides an excellent illustration of these points. He found that yttrium nitrate dissolved in ethyl alcohol could be added to a powdered uranium mineral in a mortar, whereupon grinding immediately to dryness dispersed the internal standard (yttrium) so uniformly that uranium could be satisfactorily determined in certain minerals. But the mineral euxenite is an exception, for it contains both yttrium and uranium, and this complicates the uranium determination with yttrium as internal standard. 

Figure 8-9 shows how the calibration for niobium varies with the background counting rate at a single Nb2Os concentration. Similar curves have been proved useful in a large number of uranium determinations on shipping pulp and ores. 

Ultimate composition,.71 Ultraviolet spectrography compared with x-ray spectrography, 237-239 Unmodified scattering, 18, 20, 21 Uranium, determination, by x-ray emission spectrography, 187, 199, 203, 209, 234, 329... 

Bertine KK, Chan LH, Turekian KK (1970) Uranium determinations in deep-sea sediments and natural waters using fission tracks. Geochim Cosmochim Acta 34 641-648 Bhat SG, Krishnaswami S, Lai D, Rama, Moore WS (1969) " Th/ U ratios in the ocean. Earth Planet Sci Lett 5 483-491... 

Holzbecker and Ryan [825] determined these elements in seawater by neutron activation analysis after coprecipitation with lead phosphate. Lead phosphate gives no intense activities on irradiation, so it is a suitable matrix for trace metal determinations by neutron activation analysis. Precipitation of lead phosphate also brings down quantitatively the insoluble phosphates of silver (I), cadmium (II), chromium (III), copper (II), manganese (II), thorium (IV), uranium (VI), and zirconium (IV). Detection limits for each of these are given, and thorium and uranium determinations are described in detail. Gamma activity from 204Pb makes a useful internal standard to correct for geometry differences between samples, which for the lowest detection limits are counted close to the detector. 

Characteristics such as the solution uptake rate, the sensitivity and the limit of detection for uranium determination using several nebulizers (Meinhard, MicroMist nebulizer, Q-DIHEN,... 

Aridus, USN operated in the continuous mode versus the DS-5 nebulizer used in the flow injection mode) for solution introduction in 1CP-SFMS (Element, Thermo Fisher Scientific, Bremen) for uranium determination in aqueous solution75 are summarized in Table 5.3. 

Bremen) for uranium determination in aqueous solution using different solution introduction systems. 

Tolmachyov, S. Y., Kuwabara, J., and Noguchi, H., Flow injection extraction chromatography with ICP-MS for thorium and uranium determination in human body fluids, J. Radioanal. Nucl. Chem., 261, 125-131, 2004. 

Kuwabara, J., Tolmachyov, S., and Noguchi, H., The development of flow injection technique for rapid uranium determination in urine, J. Nucl. Sci. Technol., Suppl. 3, 556-559, 2002. 

Uranium, determination of, in uranyl hydrogen orthophosphate 4-hydrate, 5 151... 

Uranium is unusual among the elements because it is both a chemical and a radioactive material. The hazards associated with uranium are dependent upon uranium s chemical and physical form, route of intake, and level of enrichment. The chemical form of uranium determines its solubility and, thus. 

McDiarmid MA, Hooper FJ, Squibb K, et al. 1999b. The utility of spot collection for urinary uranium determinations in depleted uranium exposed Gulf War veterans. Health Phys (in press). 

Schiefer HP, Gramain P, Kraeminger E. 1980. Improvement of the uranium determination in flame atomic emission spectrometry by addition of cobalt nitrate an interference agent. Fresenius Z. Anal Chem 303 29. 

Uranium Determination of uranium by measuring its activity is of considerable practical significance in searching for uranium deposits, in its technical processing, and also when monitoring the environment. Direct methods, based on measurement of a-particles... 

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