In this review the concept of Auger parameter and its applications for the XPS analysis of materials and their surfaces are described. First, the definition of the Auger parameter and the experimental methods to obtain the Auger parameter are introduced. Then the physical meaning of the Auger parameter is clarified and the relations between the bulk properties of materials, such as polarizability, refractive index, and band-gap, and the Auger parameter is interpreted. The recent applications of Auger parameter for the analysis of materials and their surfaces, such as alloys, thin films, surface layers, clusters, catalysis, and surface corrosion, are reviewed.

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In this paper, we investigated dynamic fracture energy of rocks as a dynamic index in rock blasting using Charpy impact test.
It was confirmed through the experiments that dynamic fracture energy of rocks obtained from the general equation used in Charpy impact test contains lots of kinetic energy which is consumed as scattering of rock fragment after it has failed. Also, it was found that the dynamic fracture energy of the rocks depend on the impact energy applied to the rock specimens, and its increasing rate is supposed to indicate an intrinsic dynamic fracture resistance of rocks.

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In this study, we investigated dynamic fracture toughness and crack propagation velocity of rocks by using Charpy impact test.
The results of the experiments showed that crack propagation velocity of the rocks depends on impact energy applied to it, and Q (impact energy/crack propagation velocity) correlates with static strengths of the rocks. Also, the dynamic fracture toughness of the rocks, which is calculated from the dynamic fracture energy obtained by using Charpy impact test, was found to depend on the impact energy applied with it, and correlates with crack propagation velocity and static compression and tensile strengths of the rocks.

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Lactobacillus delbrueckii cells were immobilized in polyvinyl alcohol (PVA) gel beads by using gelling reaction with PVA-boric acid-phosphate. The physical/chemical and fermentation stabilities of the immobilized cells were studied for the application of immobilized microorganism to waste water treatment. In the experiment of preparation of cell immobilized PVA beads, spherical and strong gel beads were formed at PVA concentration, 12wt%, and boric acid concentration, 5wt%. The gel beads had porous structure like spongy pore, and the cells were confirmed on the surface and the inside of the gel beads. The operational stability of the immobilized cell system was repeatedly studied in a batch fermentation. The system successfully operated for the 20 time repeated fermentations, and the gel beads were not damaged during all the runs.

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Metal matrix composites are promising material system with high strength-to-weight and stiffness-to-weight for high temperature application. Mechanical behavior of the metal matrix composite is affected by microscopically distributed residual stress owing to interaction of fibers. A periodical cluster model is made to analyze both macro-and microscopic behavior of the composite. On the basis of the periodicity of the microstructure, the homogenization theory with asymptotic expansion is applied to connect the macro behavior with the microscopic structure. Formulation on the homogenized constitutive relation is described as the solution for perturbed displacement of the composite. The fiber-matrix interface of the composite is modeled as Coulomb frictional contact under compressive residual stress. To solve for the perturbed displacement field of the composite, boundary integral formulation is introduced into the interface contact problem. The formulation enables simultaneous numerical calculations for macro-and microscopic fields to evaluate nonlinear mechanical behavior of composite. Numerical calculation is made to clear the relation of the residual stress distribution to the nonlinear behavior of the composite.

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