The exchangeable and non-exchangeable Na in tetrasilicic sodium fluor mica (Na-TSM) are characterized by different chemical shifts both in XPS and NMR. The exchangeable Na shows Na is binding energy (Na KLL kinetic energy) comparable to that for montmorillonite or analcite. The non-exchangeable Na has the characteristic low Na is binding energy (high KLL kinetic energy) and positive ²³Na NMR chemical shift. NMR spectra suggest the higher coordination symmetry and the shorter bonding with ligand for the non-exchangeable Na.

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A bright yellowish brown deposit on the walls and bases of water races in an area of paddy fields near Hontsuka Cone, Aso-Dani, is shown to be siliceous ferrihydrite. The deposit contains close to 50% Fe, 6% Si, and 13% H₂O (110°C basis). Two broad peaks at 0.275 nm and 0.155 nm, with possibly a third (much less perceptible) at about 0.22 nm, are observed in X-ray diffraction and an infrared absorption maximum for Si-O vibrations occurs at 964 cm^-1. The deposit forms as groundwater pumped from about 100 m depth and containing close to 20 g m^-3 ferrous Fe and 35-75 g m^-3 SiO₂ is released to the atmosphere and oxidised. This occurrence is similar to one in a streambed below a spring on an andesitic volcano in New Zealand and is a further example of the weathering of volcanic rocks giving rise to ferrihydrite.

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High-pressure liquid chromatography columns were packed with silica gel coated with montmorillonite ion-exchanged by cationic complex, [Co (phen) _3-x (am) _x] ⁿ⁺ (phen=1, 10-phenanthroline, am=isoleucinato or prolinato). A racemic compound of 1, 1'-binaphthol was partially resolved on the above columns using pure water as an eluting solvent. The chiral discrimination is probably attributable to the absolute configuration of amino acid ligand, but not of the complex itself.

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A new complex polytype of biotite has been examined by High Resolution Transition Electron Microscopy (HRTEM). The polytype can be written as [0 (22) ₆202 (22) ₃] or [0 (22) ₆202 (22) ₃], using the RTW notation (Ross et al. 1966). It was confirmed that the polytype has 2M₁ stacking with only two type I°₂ intrinsic faults (Baronnet et al. 1981) in one unit.

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Montmorillonite-n-alkylamine intercalation compounds were prepared by solid-solid reactions. The mixtures of Na-or Ca-montmorillonite and n-alkylamines (ntetradecylamine, n-hexadecylamine, and n-octadecylamine) were ground under a dry air atmosphere at ambient temperature. The basal spacings of the mixtures increased after grinding for only a few minutes. The basal spacings varied with the alkyl chain length of the guest n-alkylamines. The relation between the basal spacings and alkyl chain length implied that the intercalated alkylamines formed bilayers with their fully extended alkylchains inclined to the silicate sheet. The products were essentially identical to those prepared by conventional solid-liquid reactions.

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Phenolic acids are not only the normal organic constituents of most agricultural soils and the decayed products of plant lignin but also regarded as the main supplements of humic substances. In this paper, the competitive adsorptions between two kinds of phenolic acids on allophanic, halloysitic, and illitic clays were studied.
The adsorptions of p-hydroxybenzoic acid and protocatechuic acid were enhanced in the presence of phenolic acids of different kind on both halloysitic and illitic clays. On allophanic clay both constituents were adsorbed more or less, but these amounts were roughly same as the estimated values which measured by the independent phenolic acid at the same pH and concentration conditions.
The hydroxyl group at p-position and methoxyl group at m-position of benzoic acid enhanced the retentions of protocatechuic acid and p-hydroxybenzoic acid, and so the coexisting of vanillic or ferulic acid were more effective than that of other phenolic acid examined in the present study. The adsorption mechanisms were proposed that protocatechuic acid and p-hydroxybenzoic acid were mainly adsorbed by electrostatic forces on allophanic clay and by hydrogen bondings with the interlayer oxy-hydroxy groups on halloysitic clay.

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