The Malaysian Journal of Analytical Sciences Vol 15 No 1 (2011): 27 – 36

 

 

 

DISCRIMINATOR SETTING AND COCKTAIL PREPARATION FOR ANALYSIS OF ALPHA AND BETA EMITTERS IN AQUEOUS SOLUTION USING LIQUID SCINTILLATION COUNTER

 

Zaini Hamzah^1*, Masitah Alias¹and Zaharudin Ahmad²

 

¹Faculty of Applied Sciences,

Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia

²Radiochemistry and the Environment Group,

Malaysian Nuclear Agency, 43000 Bangi, Selangor, Malaysia

 

*Corresponding author: zainihamzah@live.com

 

 

Abstract

Liquid scintillation counting (LSC) is not only being used to measure pure beta emitters, but it can be used to measure both alpha and beta emitters simultaneously. Measurement of alpha and beta emitters in aqueous solution is done using a single sample. For the sample preparation, colorless detergent or emulsifier was used to incorporate the water into an organic based scintillator to produce a clear homogeneous solution, since this is the best form to give the highest count rate and detection efficiency. The instrument also need some attention, where after calibration, the LSC was set for the discriminator level which is suitable for measurement of both alpha and beta radiations. In this study, the focus is on the development of the best scintillation cocktail and establishes the best discriminator setting. From this study the best proportion of scintillation cocktail is 2:4:4 for water, toluene, and Triton-N101 (emulsifier) respectively and the best discriminator setting for alpha and beta counting are 120.

Abstract in English

 

Keywords: alpha emitter, beta emitter, cocktail, LSC, scintillant.

 

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