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Polystyrene-b-polyisoprene-b-poly(methylmethacrylate) (PS-b-PI-b-PMMA) triblock copolymer was synthesized by sequential anionic polymerization. The as-synthesized triblock copolymer contains side products of inadvertently terminated PS and PS-b-PI precursors. The side products can be effectively removed by semi-prep scale liquid chromatography using multiple injection method to obtain pure PS-b-PI-b-PMMA. It was found that the removed side product contains another polymer species, coupled PS-b-PI, which could not be recognized by size exclusion chromatography (SEC) analysis since the elution peak of the coupled product overlaps with that of PS-b-PI-b-PMMA. This study demonstrates that the size based separation of SEC is often not good enough to characterize complex polymers precisely and interaction chromatography can render unique advantage over SEC analysis.

Tesla-to-ampere ratio giving the largest error in the /spl gamma/'/sub P/-low-field-experiment has been determined using a modified noncontacting method. The total uncertainty of 0.164/spl times/10/sup -6/ has been attained. The constant of a solenoid and the /spl gamma/'/sub P/-value have been corrected for magnetic susceptibility of air. The result is /spl gamma/'/sub P/=2.675 154 18/spl times/10/sup 8/ s/sup -1/ T/sup -1/ (Tesla BI-90) with the total uncertainty of 0.18/spl times/10/sup -6/.

A new method and principle were presented for the continuous measurement of the depth-dependent reflection coefficient of Rayleigh waves or their pulse interacting with various surface discontinuities. The method was to record the reflection echo amplitudes for varying depth during scanning the Rayleigh wave pulse with a small lateral beam width along a surface discontinuity with a small slope in depth. In the experiments using a declined slot and intensively focused Rayleigh waves, the coefficients were continuously measured with quite good reproducibility in the range of 0.05

Green's function is used in order to derive the analytical solution for the change in impedance due to a presence of the flaws in a conductor. This solution is applied to a cylindrical flaw and a spherical flaw whose radii are much smaller than the radius of the test coil. For both cases, the change in impedance is obtained within Born's limit.

The impedance of a single-turn coil which surrounds a conducting cylinder with a flaw is calculated employing Green's function technique. The Born approximation is used in order to know how the impedance change due to the presence of a flaw depends on the conductivity and size of a flaw.