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Continuous 222Rn monitoring in soil gas since November 22, 2004 has revealed variability in activity concentration with time in the semi-natural woods on the campus of Hokkaido University in Sapporo, Japan. Among various factors affecting soil radon levels and variability, temperature was found to be dominant during three seasons when activity concentrations of 222Rn showed a diurnal high and nocturnal low with a boundary around 10 o'clock in the morning. This pattern was disturbed by low pressure fronts with occasional rain. The activity gradually decreased as soil temperatures decreased from late November to mid-December. After the ground surface was completely covered with snow, soil radon levels became low with a small fluctuation. There were several peaks of 222Rn on the time-series chart in winter. Those peaks appearing in early winter and early spring may be interpreted by considering meteorological parameters. In a few cases, the radon activity suddenly increased with increasing pressure in the soil at a depth of 10 cm, which may be associated with subsurface events such as seismic activity in the area

Poly(4-hydroxystyrene) (PHS) has been used in current lithography as a backbone polymer and is also a promising material for EUV and electron beam (EB) lithography. PHS is efficiently deprotonated after the ionization of its radical cation at a low pK a (<0). Thus, a hydroxystyrene unit is incorporated in the chemically amplified resist formula as a proton source. The deprotonation mechanism after ionization can be characterized by using pulse radiolysis techniques. In this study, the dynamics of PHS radical cations generated upon exposure to EB were investigated in various solvents such as ketones, acetates, and nitriles. The observed deprotonation rate is controlled by intramolecular interaction in the solvents with low proton affinities. However, it is suggested that the formation of the hydrogen bonding complex between a hydroxyl group of PHS and a solvent molecule increases the proton transfer rate in dimethyl sulfoxide and pyridine with higher proton affinities (>850 kcal/mol).

Radon ((222)Rn) and carbon dioxide were monitored simultaneously in soil air under a cool-temperate deciduous stand on the campus of Hokkaido University, Sapporo, Japan. Both (222)Rn and CO(2) concentrations in soil air varied with atmospheric (soil) temperature in three seasons, except for winter when the temperature in soil air remained constant at 2-3 degrees C at depth of 80 cm. In winter, the gaseous components were influenced by low-pressure region passing through the observation site when the ground surface was covered with snow of ~1 m thickness. Carbon isotopic analyses of CO(2) suggested that CO(2) in soil air may result from mixing of atmospheric air and soil components of different origins, i.e. CO(2) from contemporary soil organic matter and old carbon from deeper source, to varying degrees, depending on seasonal meteorological and thus biological conditions.

Environmental radionuclides ( 40 K, 137 Cs, 210 Pb, 226 Ra) were determined in soils under semi-arid stands, a transition area from thorn to deciduous forest in El Angolo, and heath stands in the Alto Mayo in Northern Peru in order to elucidate their activity level in soil, and to trace underground environment in remote areas of little anthropogenic intervention. Anthropogenic 137 Cs was only found in the uppermost portion of the soils in small amount, whereas the 210 Pb activity was exceptionally high at the soil surfaces in a tropical stand of Alto Mayo. The results suggest a fallout nuclide, 210 Pb, having been transported from local source(s) not to be specified yet.

Several factors controlling the soil radon level in the present site were found to be changing air-filled porosity caused by fluctuations in moisture content, differences between the atmospheric and soil temperatures as well as volumetric (226)Ra content of the soil. The radon activity increased significantly in early October, especially at point 1, possibly as a result of a magnitude 8.0 earthquake which occurred on September 26, 2003, with epicenter located offshore near Tokachi, Hokkaido.

Depth distribution profiles of environmental radionuclides (137Cs and 210Pb) have been investigated in soil to elucidate the underlying environment of semi-natural temperate deciduous and/or coniferous forest soils in Slovenia (Žirovski vrh, Idrija, Kočevski Rog, Pohorie, Gorišnica and Rakitna). Surface enrichment of both nuclides was observed at all the sites investigated in this study, suggesting that the soils had undergone little natural or anthropogenic disturbance for at least the last several decades. Apparent annual burial rates of 137Cs (0.1–0.2 cm y−−1) were estimated to be about 1.3 times higher than those of 210Pb at individual sites of different lithology, which suggests strong affinity of 210Pb to soil organic matter. Variability of the vertical distribution profiles of these nuclides depends not only on “in situ” pedology but also on geographical and meteorological conditions, especially precipitation and wind direction.

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