Measurements of the cosmic-ray hydrogen and helium spectra at energies from 20 to 800 TeV are presented. The experiments were performed on a series of twelve balloon Ñights, including several long duration Australia to South America and Antarctic circumpolar Ñights. No clear evidence is seen for a spectral break. Both the hydrogen and the helium spectra are consistent with power laws over the entire energy range, with integral spectral indices 1.80^0.04 and for the protons and helium, respec-1.68~0 .06 0.04 tively. The results are fully consistent with expectations based on supernova shock acceleration coupled with a "" leaky box ÏÏ model of propagation through the Galaxy.

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Laser-induced fluorescence spectroscopy and batch experiments were combined to study the sorbed species of Eu(III) on amorphous silica and montmorillonite. In the silica system, more than six water molecules were removed from the first coordination sphere of Eu(III) above pH 7, suggesting that Eu(III) was incorporated into the silica. This fact was confirmed through the dependence on aging time and the desorption behavior after acidification. In the montmorillonite system, the Eu(III) aquo ion was sorbed as an outer-sphere complex on montmorillonite below pH 6. Two species with different fluorescence lifetimes were separately detected in higher pH regions in montmorillonite system. The faster component may be Eu(III)-hydroxide precipitates or Eu(III) surface precipitates, while for the slower component, the number of water molecules in the first coordination sphere of Eu(III) was 2-3. Similar studies on Eu(III) sorbed on kaolinite was also conducted for comparison with the results on montmorillonite.studies have employed LIF to study the aqueous and solid species of Eu(III).In this study, LIF was applied to Eu(III) sorbed on unporous silica (aerosil) and montmorillonite. Europium(III) is a member of the lanthanide(III) elements which include various fission products and is also regarded as an analogue of actinide(III) ions; unporous silica represents the surface of silicate minerals and montmorillonite is an important buffer material in repositories. In some parts of this study, kaolinite has also been employed, for comparison. The fluorescence lifetime (mainly 5 D 0 -• 7 F 2 ) and the emission spectrum of Eu(III) were employed to obtain structural information on the sorbed species. The lifetime often contains information on N U20 , the number of water molecules in the first coordination sphere of Eu(III). Based on the results of LIF and batch experiments using Eu-152 tracer, characterization of the sorbed species of Eu(III) was investigated.