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X-ray diffraction analysis is one of powerful tools on the dislocation analysis and this method can be applied reasonably for many metals with isotropic crystal structure such as bcc and fcc. In this study, modified Williamson-Hall analysis was applied for martensitic steels containing 0.006 -0.26 mass% carbon and proved that the value of dislocation density increases with increasing the carbon content. However, martensitic steels containing solute carbon have bct structure characterized by different lattice constants on a-axis and c-axis. With increasing solute carbon, a-axis shrinks but c-axis is elongated. This leads to the peak séparation in an X-ray diffraction peak and causes an increase of the full-width at half-maximum (FWHM) in the diffraction peak. This suggests that the value of dislocation density is over estimated due to the effect of peak separation in as quenched martensitic steels with solute carbon. It was found that the increment of apparent dislocation density Δρ' is expressed by the following equation as a function of the amount of solute carbon (mass%C), independent of the values of true dislocation density and the screw component of dislocation. Δρ[m −2 ] =1.68×10 17 (mass%C) 2 As a result, it is concluded that the true dislocation density is constant at 4.5×10 15 m 2 in martensitic steels which have solute carbon more than 0.14 mass% at least.

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We synthesized rhodamine-labeled β-lactoside and assessed its rotatory diffusion rates in aqueous media containing various oligosaccharides through fluorescence intensity distribution analysis-polarization measurements to find that its rotatory diffusion rates decrease in the presence of the coexisting oligosaccharides. Especially, the coexisting lactose lowered the rotatory diffusion rate more effectively than the other disaccharides did. This restrained rotatory diffusion arises from intermolecular carbohydrate–carbohydrate interactions between the rhodamine-labeled β-lactoside and the coexisting lactose. We also detected intermolecular bindings between the rhodamine-labeled β-lactoside and monosialyl-disaccharides (3′- and 6′-sialyllactoses). These data clearly show that the fluorescence intensity distribution analysis-polarization-based system is quite advantageous to probe carbohydrate–carbohydrate interactions.