Tsuyoshi Sugano

Solubilization of Polycyclic Aromatic Hydrocarbons in Bentonite/Aqueous Systems by Nonionic Surfactants

Enhanced solubilization of phenanthrene and pyrene from bentonite in micellar solutions of Brij 30 and Triton X-100 has been studied. Experiments in batch bentonite/aqueous systems were conducted to investigate the effectiveness of solubilization of phenanthrene and pyrene. The results obtained in the present study are as follows:The solubilization of pyrene from bentonite in surfactant solutions was very low because of low water solubility and strong sorption onto bentonite of pyrene. Meanwhile, the solubilization of phenanthrene increased at bulk surfactant concentrations greater than the surfactant critical micelle concentration and was in the order of Triton X-100 > Brij 30. The solubilization of phenanthrene was also analyzed based on the partitioning of phenanthrene between bentonite, nonionic surfactant micelles and aqueous solution surrounding the micelles.

Fundamental Study on Composite Sensitivity Analysis of Electrode Array System for Resistivity Measurements.

For the geoelectrical measurements and their inversion analysis, a more accurate and reliable resistivity data aquisition system is needed more than ever. As the direct current resistivity method most commonly used for the exploration and evaluation of the target inhomogeneity is a very useful and practical tool for the electrical imaging technique so-called resistivity tomography, it may be exceedingly important to incorporate a new sensitivity method developed by the author for determining more exactly the earth resistivity target inhomogeneity, for examples, faults, fractures, layers, water bearing zones, and geological structures under various conditions and environments. Especially, no technique has been investigated to interprete the local and lateral resistivity changes of the near surface inhomogeneities and detailed deep massive resistivity structures.In this paper, by composite analysis of sensitivity distributions, the author has clarified the relation among various surface electrode arrays. The two-electrode system, the four-elctrode systems such as the Wenner, the Eltran and the Staggered electrode configuration (so-called the tripotential system) and the six-electrode system have been discussed. Also an example of the sensitivity composite analysis for the solid electrode array system has been investigated as an aid to analyze the response caused by target inhomogeneity more practically.