Optical disk memory using amorphous rare-earth-transition-metal (RE-TM) films have been developed for erasable optical disks for applications of high density, large volume data storage. In order that the film can be used in applications, it is necessary to improve its reliability. The key factors in improving the reliability of these disks are reduction of the RE-TM film oxidation and improvement of heat-resistance property of organic substrate.
Tb-Co film forming on the epoxy-resin substrate with adequate sputtering conditions protects against oxidation and shows good magneto-optical properties. In addition, the epoxy-resin substrate has small birefringence-retardation and a shape fabricated by means of an Omega-casting method. These results demonstrate that the optical disk with Tb-Co on epoxy substrate is suitable media for erasable disks for practical applications.

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Due to the component separation, the elasticity of polytrimethylene terephthalate/polyethylene terephthalate (PTT/PET) side-by-side bi-component filament decreased dramatically. Analysis shows that the bonding fastness between two components of PTT/PET filament is closely related to the copolyesters and recrystallization which produced in the interface during spinning process. Covalent bonds of copolyster can greatly strengthen the bonding and two kinds of molecular chains are locked together by recrystallization. The interfacial bonding with less copolymer and recrystallization can be destroyed by the extreme alkaline environment of dyeing and finishing processes, leading to the loss of filament elasticity. Besides, the location and duration for PTT and PET fluids to contact and cooling rate are factors which influence the generation of copolyester and recrystallization in spinning process.

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Our research aims to study the properties of real shark skin in accordance with its topographical features and the biomimicry for friction reduction. In this paper, we are focusing on antifouling surface modification based on the surface roughness and frictional resistance inspired from the shark’s denticule arrangements. Biomimetic shark skins were prepared using the silicone laminated transfer molding method to investigate the antifouling effects. Anti-algae formations were investigated to examine and assess the antifouling properties of the biomimetic shark skin surface microstructure. The results indicated that the effect of microreplication with shark skin on the surface had reduced 13% - 40% of algae formation. The characteristics of the hydrophobic properties for shark skin had also been investigated through the analysis of the contact angle (CA). Scanning electron microscopy (SEM) is used to observe the surfaces morphologies of the shark skin as well as the biomimetic shark skin. In addition to that, the frictional resistance experiment was carried out to evaluate the friction of coefficient (COF) of different surface modifications. The frictional resistance experiment for real shark skin and replicated shark skin demonstrated lowered COF value ranging from μ = 0 to 1, compared to the COF for controlled surface whereby the value ranges from μ = 0 to 5.

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To study the influence of the CO₂ on the cutting performance, the heat input due to preheating flame q_G, and that due to the combustion of the material being cut q_B are estimated by performing a three-dimensional nonlinear heat conduction analysis that considers the temperature dependence of the thermomechanical properties. Spot heating tests are performed to identify the heat input parameters of the preheating gases H₂ and H₂-CO₂. Gas cutting tests are performed to identify the characteristics of the cutting groove shape while employing the selected preheating gases. Based on the information of the spot heating, and the gas cutting tests, a three-dimensional heat conduction analysis is performed to identify the temperature fields along the thickness direction of the workpiece. A new technique for the estimation of the temperature fields considering inclined cutting-fronts based on Matsuyama’s theory is proposed. The role of the preheating heat input and the material combustion heat input for the selected gases is examined. Based on the simulation results of this study, CO₂ deterioration mechanism on the cutting performance is discussed. From the study, the following results were obtained: (1) A new procedure for the kerf temperature estimation throughout the plate thickness based on the two-dimensional analysis of Matsuyama is established. The procedure allows a smooth and continuous temperature distribution through the plate thickness direction. (2) By applying the proposed procedure, it is possible to estimate the three-dimensional kerf temperature distribution on thick plates and allows the consideration of inclined cutting fronts. (3) By evaluating the preheating, and the material combustion heat input, it is observed a substantial declined in q_G when employing CO₂ while q_B remains unchanged regardless of the employed preheating gas.

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目的 : 小型核を主体とする低異型度の乳管癌に対し, 良性病変との鑑別に有用な細胞所見を検討する.
方法 : 悪性の疑いまたは鑑別困難と判定していた症例のうち, 小型核を主体とする乳管癌 37 例, および筋上皮細胞が不明瞭な細胞集塊が出現していた良性病変 13 例の計 50 例に対し, (1)双極裸核, (2)細胞集塊の重積性, (3)細胞間結合性, (4)核小体, (5)クロマチンパターン, (6)核溝の 6 項目の細胞所見についてスコア化を行い, それぞれの出現頻度を比較した. さらに統計学的有意差がみられた細胞所見に対して点数加算を行い, 乳管癌と良性病変の鑑別を試みた.
成績 : 6 項目の細胞所見のうち, 双極裸核 (p=0.007), 核溝 (p=0.02) に統計学的有意差がみられた. 双極裸核は対物レンズ 40 倍で 1 視野あたり平均 20 個を超えるものを score 1, 6∼20 個であるものを score 2, 5 個以下であるものを score 3, 核溝は明らかでないものを score 1, 核溝がみられるものを score 2 とし, それらのスコアの合計が 4 点以上であるものを乳管癌とすると, 感度 76%, 特異度 77%, 陽性的中率 90%, 陰性的中率 53%であった.
結論 : 低異型度乳管癌と良性病変の鑑別に, 双極裸核の数および核溝に着目し, スコア化を行うことは鑑別困難症例の減少につながると考えられた.

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