MEASUREMENT WITH LIQUID SCINTILLATORS

Journal Article · Mon Oct 01 04:00:00 EDT 1962 · Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech.

OSTI ID:4752354

Rapkin, E

Liquid scintillation counting has gained ground as a popular method for the measurement of weak activities of alpha and beta emitters. It permits samples of very diverse kinds and physical constitutions to be counted and also the measurement of several radioisotopes in one specimen. An important basis for its popularity is the possibility of fully automatic operation which it offers. Modern instruments can accommodate up to 200 samples and are so arranged that either two isotopes can be assessed simultaneously in the same specimen or, alternativeiy, measured in different specimens. Two types of liquid scintillation counter are available on the market: coincidence counters and equipment using one photomultiplier. In spite of the advantage of being cheaper, systems with only one photomultiplier are less popular because of the high background effect, because they cannot be automated, and because of the necessary dark adaptation. In- general, specimens are dissoived in the scintillator liquid, introduced into the counting chamber and the count made. Toluene is used throughout as the solvent medium, substances normaily insoluble being dissolved with the aid of organic base Hyamin. In comparison with routine measurements, considerably greater care is required in the counting of very low activities such as occur in geological or archaeological dating. The carboniferous material is, in this case, burnt and the resulting C/sup 14/O/sub 2/ converted by a series of well worked out chemical reactions into a pure liquid. Conversion into benzene as an end product is preferred today. Similarly in the determination of extremeiy small activities of tritium in water samples conversion, via acetylene, into tritiated benzene is an excellent possibility. The liquid scintillation technique can also be empioyed for solid or liquid samples which are either completely insoluble or only dissolve with great difficulty in the usual scintillator solutions. (auth)

• Research Organization: Packard Instrument Co., Inc., La Grange, Ill.
• NSA Number: NSA-17-004818
• OSTI ID: 4752354
• Journal Information: Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech., Journal Name: Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech. Vol. Vol: 7; ISSN ATWSA
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

ACETYLENES
AGE ESTIMATION
ALPHA PARTICLES
BACKGROUND
BENZENE
BETA PARTICLES
CARBON 14
CARBON DIOXIDE
COINCIDENCE METHODS
GEOLOGY
INSTRUMENTS AND INSTRUMENTATION
LIQUIDS
MEASURED VALUES
PHOTOMULTIPLIERS
RADIOISOTOPES
SAMPLING
SCINTILLATION COUNTERS
SOLUTIONS
SOLVENTS
TOLUENE
TRITIUM
WATER