No abstract

Bentonite mixed soil, which is a mixture of bentonite with sand and gravel, can be easily compacted by adjusting the blending degree, and it is difficult for water to pass through and exhibits low permeability. It is widely used at construction sites because it can be mixed on-site and has good workability. Examples of its use include impermeable layers at waste disposal sites and measures to contain heavy metals from rocks generated from construction sites. The main component of bentonite is smectite, which is a swelling clay mineral, and the swelling property and consistency characteristics determine the engineering properties. In particular, low permeability is considered to be strongly influenced by the electrochemical properties at the crystal level peculiar to smectite. In this study, the mechanism of expression of engineering properties of bentonite mixed soil was investigated focusing on the mineralogy properties of smectite. Specifically, X-ray and near-infrared analysis were performed to clarify the crystal structure of smectite and the adsorptivity of water molecules. The change in interlayer distance were clarified by XRD. Information on the behavior of water molecules was obtained by NIR. From these analyses, we obtained information on the swelling, consistency and micro-physical properties of smectite, which is the main component of bentonite, related to water permeability.

To elucidate mechanisms of fruit deformation in apple, we investigated deformation of 'Fuji', 'Megumi', 'Tsugaru', and 'Orin'. Among these cultivars, no significant difference was nored in the deformation indexes among weight classes, suggesting that they deformed similarly, irrespective of the fruit size. Fruits were easily deformed in the longitudinal direction because the deformation index in that direction was larger than in the transverse direction. The deformation indexes of 'Fuji' were larger than those of other cultivars. The maximum radii of transverse sections of 'Fuji' and 'Orin' appeared near the middle of the two locules, but those of 'Megumi' and 'Tsugaru' appeared near the right locule. Because the position of the maximum radius of transverse section was set as 0°, we investigated those of the minimum radius of transverse section, the minimum longitudinal diameter, and maximum longitudinal diameter. The maximum longitudinal diameter of all cultivars was near the maximum radius of the transverse section. However, the minimum radius of transverse section and minimum longitudinal diameter were at different positions in the four cultivars. The minimum radius of transverse section and minimum longitudinal diameter of 'Fuji' appeared almost symmetrically against the diameter passing through the maximum radius of the transverse section. Key Words：deformation fruit, deformation index, L/D ratio, Malus × domestica Borkh. キーワード：変形果，変形指数，L/D 比，Malus × domestica Borkh.