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1.
Science ; 167(3918): 523-5, 1970 Jan 30.
Article in English | MEDLINE | ID: mdl-17781480

ABSTRACT

Analytical data for 42 major and trace elements were mostly obtained by a combination of instrumental and radiochemical neutron activation analyses using both thermal and 14-million-electronvolt neutrons. Excesses of nitrogen and chlorine in the fines, compared with the rocks, are attributed to the solar wind. A striking similarity for contents of seven elements in lunar metal and metal from the calcium-rich achondrite Juvinas was noted. Fractional dissolution was used to separate five radionuclides produced by cosmic-ray bombardment in the fines and rock 57-40. Results for argon-39 from the reaction potassium-39 (n,p), and for argon-37, from the reaction calcium-40 (n,a), seem to require a neutron spectrum conitaining more neutrons below 2 million electronvolts than the evaporation spectrum or that given by Arnold, Honda, and Lal (1) or a strong time dependence for the neutron flux.

2.
Science ; 167(3918): 543-5, 1970 Jan 30.
Article in English | MEDLINE | ID: mdl-17781490

ABSTRACT

The concentrations and isotopic abundances of the rare gases have been investigated in fines and three types of rocks. The results obtained from different grain-size fractions and from samples etched to different degrees with nitric and hydrofluoric acids demonstrate the strong concentrations of the solar-wind component in the surface layers of the grains. Exposure ages as well as gas retention ages have been determined in different types of Apollo 11 material. Hydrogen, nitrogen, and other gases have been analyzed by a high-resolution mass spectrometer. As compared with that in terrestrial water, deuterium is depleted by at least a factor of 3 in the investigated type C rocks.

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