Radium determination

Caldes, A., Gomez, E., Garcias, F., Casas, M., and Cerda, V., A sequential injection method for radium determination in environmental samples, Radioact. Radiochem., 10, 16-21, 1999. 

A majority of the radiochemical methods for radium determination in environmental samples takes advantage of its isomorphous co-precipitation with barium as its sulfate. Very small amounts of the barium carrier are typically used to minimize the selfabsorption of a-particles from the radium. 

MSFiA-MPFS combination for radium determination in waters. MR micropump, R reagent. 

Y. Fajardo, E. Gomez, F. Garcias, V. Cerda, M. Casas, Development of an MSFIA-MPFS pre-treatment method for radium determination in water samples, Talanta 71 (2007) 1172—1179. 

From radium called niton at first, L. nitens, shining) The element was discovered in 1900 by Dorn, who called it radium emanation. In 1908 Ramsay and Gray, who named it niton, isolated the element and determined its density, finding it to be the heaviest known gas. It is essentially inert and occupies the last place in the zero group of gases in the Periodic Table. Since 1923, it has been called radon. 

Although the Curies noted that one equivalent gram of radium released one hundred calorics of heat per hour, they were uninterested in the practical implications of this, as they were both devoted to pure scientific discovery. During their work with pitchblende in 1898, the Curies discovered two new radioactive elements, which they named polonium (in honor of Marie s homeland) and radium. By 1902 they had isolated a pure radium salt and made the first atomic weight determination. 

In 1898, Marie and Pierre Curie isolated two new radioactive elements, which they named radium and polonium. To obtain a few milligrams of these elements, they started with several tons of pitchblende ore and carried out a long series of tedious separations. Their work was done in a poorly equipped, unheated shed where the temperature reached 6°C (43°F) in winter. Four years later, in 1902, Marie determined the atomic mass of radium to within 0.5%, working with a tiny sample. 

Cochran JK, Masque P (2003) Short-lived U/Th-series radionuclides in the ocean tracers for scavenging rates, export fluxes and particle dynamics. Rev Mineral Geochem 52 461-492 Cohen AS, O Nions RK (1991) Precise determination of femtogram quantities of radium by thermal ionization mass spectrometry. Anal Chem 63 2705-2708 Cohen AS, Belshaw NS, O Nions RK (1992) High precision uranium, thorium, and radium isotope ratio measurements by high dynamic range thermal ionization mass spectrometry. Inti J Mass Spectrom Ion Processes 116 71-81... 

Joarmon S, Pin C (2001) Ultra-trace determination of Ra in thermal waters by high sensitivity quadrapole ICP-mass spectrometry following selective extraction and concentration using radium-specific membrane disks. J Anal At Spectrom 16 32-37... 

Morvan K, Andres Y, Mokili B, Abbe JC (2001) Determination of radium-226 in aqneons solutions by alpha-spectrometry. Anal Chem 73 4218-4224... 

Volpe AM, Olivares JA, Murrell MT (1991) Determination of radium isotope ratios and abundances in geologic samples by thermal ionization mass spectrometiy. Anal Chem 63 913-916... 

Krishnaswami S, Graustein WC, Turekian KK, Dowd F (1982) Radium, thorium, and radioactive lead isotopes in groundwaters application to the in-situ determination of adsorption-desorption rate constants and retardation factors. Water Resour Res 6 1663-1675 Krishnaswami S, Bhushan R, Baskaran M (1991) Radium isotopes and Rn in shallow brines, Kharaghoda (India). Chem Geol (Isot Geosci) 87 125-136 Kronfeld J, Vogel JC, Talma AS (1994) A new explanation for extreme " U/ U disequilibria in a dolomitic aquifer. Earth Planet Sci Lett 123 81-93... 

Moore WS (2000) Determining coastal mixing rates using radium isotopes. Cont Shelf Res 20 1995-2007 Moore WS, Shaw X J (1998) Chemical signals from submarine fluid advection onto the continental shelf J GeophysRes 103 21543-21552... 

While these data and the resulting maps are useful in illustrating both the trends and variability in surface radium concentrations, detailed field examination of surface radium concentrations in selected areas is needed to determine the reliability of... 

Powers, R.P., Turnage, N.E., and Kanipe, L.G., Determination of Radium-226 in Environmental Samples, in Proc. Natural Radiation Environment III,... 

The main parameters determining the indoor radon concentration in detached houses are the effective radium concentration (product of the radium concentration and the emanation factor) and the permeability of the ground. The effects of other factors are not so easy to ascertain from the existing data. 

The mean radon concentrations determined by the passive detectors are based on calibrations using NBS standard radium-226 solutions and also from participation in the OECD (Nuclear Energy Agency)/CEC radon dosimeter intercomparisons (Commission of the European Communities, 1986) held at the U.K. National Radiological Protection Board (NRPB). Recent calibrations of the new LR-115 based detectors, in terms of response to radon concentrations and F factors have been carried out at the NRPB, which assistance is greatly appreciated. For the etching and track counting procedures used the inner LR-115 piece in the detectors has a mean sensitivity of approximately 1.6 tracks cm 2 kBq l m hr l. 

Baskaran et al. [856] have discussed the rapid extraction and determination of thorium, lead, and radium species from large volumes of seawater. 

Burnett and Tai Wei-Chieh [15] used a liquid scintillation to determine radium radionucleides in seawater. The method was applied in the 7-35 dpm 100 kg-1-range using 1 litre samples. 

Cohen and O Nions [16] determined femtogram quantities of radium radionucleides in seawater by thermal ionisation mass spectrometry. 

Baskaran et al. [30] pumped seawater at 35l/min and collected dissolved species on cartridges prior to determining radium, thorium, and lead by y counting methods. 

Whether Wells s novel affected Soddy as much as Soddy s Interpretation of Radium influenced Wells is impossible to determine, but Soddy s move into monetary theory in the postwar period was, in some ways, already implicit in his alchemical vision of the new science.8 Modem alchemy—the atomic science of transmutation, with all its alchemical connections to spiritual systems, gold, and even greed—that Soddy had been exploring in his pre-War writings may have helped turn this Nobel Prize-winning chemist into what was commonly called a money crank. ... 

We can estimate densities of solids from the information in Figure 10-1. Radium has Z = 88 and an approximate atomic volume of 40 cm3 /mol. Then we use the molar mass of radium to determine its density ... 

Moore, W.S. 2000. Determining coastal mixing rates using radium isotopes. Continental Shelf Research 20(15) 1993-2007. 

---