Radium disk

The laboratory participated to an intercomparison organized by the National Physical Laboratory (N.P.L., U.K.) bearing on an aqueous sample a mixture of a and p emitters in 2 M HNO3 medium. A known mass was passed through two superposed membranes radium disk above the strontium disk. 

The radium disk (AnaLigRaOl) is the simplest method for the determination of Ra and Ra. Of the five radium isotopes, the above-mentioned two isotopes represent the most significant of the health hazards and require the most accurate detection. The sample is... 

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... 

Ra determination in environmental samples (highly saline thermal waters) by ICP-QMS with ultrasonic nebulization has been described by several working groups. Radium was preconcentrated and isolated from the matrix elements by selective extraction using a radium specific solid phase extraction membrane disk designed for radioactive counting methods as proposed by... 

No aqueous reference material was available in the laboratory during the validation tests. This test was thus performed on biological reference materials milk powder (IAEA-152) and dried clover (IAEA-156). These samples had to undergo a thermal mineralization at 500 °C. The salts were recovered in 1 M hydrochloric acid. Then alcalino-terrous elements were preconcentrated by coprecipitation in the form of calcium phosphate in basic medium to get rid of some undesirable elements. In order to eliminate a possible presence of Ra an Empore Radium Rad Disk was superposed on the usual Sr Rad Disk. 

His equipment was similar to Marsden s, a small brass box fitted with stopcocks to admit and evacuate gases from its interior, with a scintillation screen mounted on one end. For an alpha source he used a beveled brass disk coated with a radium compound ... 

Recently, Smith et al. [47] demonstrated the use of solid-phase extraction disks for the determination of radiostrontium Tc, and radium in surface water, ground-... 

Recently, a radium-specific disk, which is highly selective for Ra, has been developed by Empore. Joannon and Pin ° used this disk for chemical separation and determination of Ra in spring water with ICP-MS detection. In this paper, conventional separation methods using cation-exchange resins were compared to Sr-Spec and the Ra-disk method. The Ra-disk method can be applied to other environmental water samples, such as river and ground waters. Since these waters are used for drinking, determination of Ra in them will be inportant for radiation dose estimation in the future. 

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