The half-life of 87Rb was measured by a liquid scintillation method according to the efficiency tracing method. The measuring sample of rubidium chloride was dissolved in a scintillation cocktail of Insta-gel, and the rubidium was determined by gravimetry as tetraphenylborate. The result was (5.56 +/- 0.025) x 10(10) years.

A new radioanalytical method was developed for rapid determination of (226)Ra in human urine samples. The method is based on organic removal and decolourisation of a urine sample by a polymeric (acrylic ester) solid phase sorbent material followed by extraction and preconcentration of (226)Ra in an organic solvent using a dispersive liquid-liquid microextraction technique. Radiometric measureme...

Wastes containing radioactive and organic compounds (mixed wastes) are difficult to dispose because of the regulations established for nuclear and hazardous wastes. Mixed wastes originate mainly in the emulsions generated in beta emitter determinations by Liquid Scintillation techniques. The use of plastic scintillators instead of liquid cocktails may facilitate the segregation, after measureme...

The indoor 222Rn radionuclide was directly absorbed in typical 20 ml glass scintillation vials by passing -3 dm3 of ambient air through 16 ml of water-immiscible non-volataile scintillation cocktail Ultima-Gold F for 10 min. The activity of radon and its two α-emitting daughters: 218Po and 214Po, was determined with the BetaScout low-background liquid scintillation counter. The limit of 222Rn d...

Expressions are derived for the fluorescence response functions of organic solution systems in which non-radiative energy transfer occurs and obeys either Stern-Volmer or Forster kinetics. Scintillation pulse shapes are evaluated for typical crystals, binary and temary liquid solutions, and binary plastic solutions. The scintillation decay time is inadequate to describe the time characteristics...

The determination of radium and/or uranium concentrations in natural waters is useful in a wide range of environmental studies. In this work, a low-background liquid scintillation system (Wallac, Quantulus 1220) was used to determine simultaneously 226Ra and uranium (total) activities in natural water samples. Sample preparation involved filtration and 1 : 10 concentration by evaporation. Then,...

The TopCount Microplate Scintillation and Luminescence Counter has been widely used in biopharmaceutical assays involving both radionuclide and luminescence measurement. A new feature allows the use of TopCount for measuring a high energy beta emitter such as P by Cerenkov counting, a well-known measurement technique that has the main advantage of not requiring the addition of scintillation coc...

Liquid scintillation spectrometry is widely used for the analysis of alpha and beta emitting radionuclides. Robust calibration of liquid scintillation (LS) spectrometers is fundamental to accurate LS measurement but at the same time is time consuming and costly, particularly if a wide range of radionuclides are analysed by the laboratory. The frequency of the calibration varies in different lab...

A method is described using Triton X-100 scintillant to simplify liquid scintillation counting of (55)Fe alone or in combination with (59)Fe. The Triton acts as an efficient solubilizing agent allowing small volumes of aqueous solutions of iron compounds in hydrochloric acid to be counted. The efficiencies achieved are comparable with those of previously described methods whilst the technique i...