Other
Scientific paper
Oct 1958
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1958gecoa..14..340e&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 14, Issue 4, pp.340-363
Other
1
Scientific paper
It is expected that the long-lived radionuclides Al 26 , Be 10 and Fe 60 (with its daughter Co 60 ), among others, are present in detectable amounts in meteorites as the result of the action of cosmic rays in space. For the detection and measurement of these activities, which have considerable potential significance, chemical isolation and purification are essential. Chemical procedures developed for the separation and purification of aluminium, beryllium, iron and cobalt from iron and stone meteorites, tektites, and terrestrial silicate materials are described in detail. The prime objective was radiochemical purity of the isolated radioelements, chemical purity and chemical yields being of secondary importance. Ion-exchange and solvent-extraction techniques were used wherever possible because of their high specificity and applicability to very small quantities of elements. Al 26 and Be 10 are prepared for counting in the forms of Al 2 O 3 and BeO. Fe 60 is best detected by extraction of its active daughter Co 60 , counted as CoS. The identity of a radionuclide is established by the criterion of constant specific activity upon recycling the sample through the chemical purification procedure. Special low-background counters have been constructed for the detection and measurement of feeble amounts of beta emitters in the form of small solid samples. The backgrounds are about 0.4 count min -1 and are exceptionally constant. In routine operation 3-4 day backgrounds are alternated with 6-8 day sample counts, yielding a lower counting rate limit (2 criterion) of 0.017 count min -1 . With counting yields of about 40 per cent and specimen sizes of about 100g, it is possible to detect radionuclides at a specific activity of 0.0004 dis min -1 (g specimen) -1 in favourable cases. Thin-sample counting yields have been measured for Al 26 and Na 22 . Sample-thickness factors have been determined for Al 26 in Al 2 O 3 and Be 10 in BeO.
Ehmann William D.
Kohman Truman P.
No associations
LandOfFree
Cosmic-ray-induced radioactivities in meteorites--I Chemical and radiometric procedures for aluminium, beryllium and cobalt does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cosmic-ray-induced radioactivities in meteorites--I Chemical and radiometric procedures for aluminium, beryllium and cobalt, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmic-ray-induced radioactivities in meteorites--I Chemical and radiometric procedures for aluminium, beryllium and cobalt will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1144010