Sains Ma1aysiana 26(3&4): 81-86 (1997)                                                                    Sains Fizis dan Gunaan/

                                                                                                                                    Physical and Applied Sciences

Activity determination of ¹³⁷Cs in NPL’s

ampoule using a point source

Supian Bin Samat

Department of Physics

Faculty of Physical and Applied Sciences

Universiti Kebangsaan Malaysia

43600 UKM Bangi Selangor D.E. MALAYSIA

ABSTRACT

The activity of two liquid mixed radionuclide sources in NPL'S standard glass ampoules were determined by gamma-ray spectrometry measurement using a standard point source placed at 38.5 cm axially above the detector. A radio nuclide ¹³⁷Cs was chosen, Results obtained were within 3% agreement with the calculated value. The same degree of deviation was obtained when the NPL standard source of equal geometry, chemical composition and density was used.

ABSTRAK

Keaktifan dua sumber radionuklid campuran cecair yang terkandung dalam bekas kaca piawai NPL ditentukan dengan kaedah pengukuran spektrometri sinar-gama menggunakan satu sumber titik piawai diletakkan pada 38.5 em di atas pengesan, Satu sumber radionuklid ¹³⁷Cs dipilih. Keputusan yang diperoleh bersetuju dalam lingkungan 3% dengan nilai yang dikira. Darjah simpangan yang sama diperoleh apabila sumber piawai NPL yang sama dari segi geometri, komposisi kimia dan ketumpatan digunakan,

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