A new method for determination of concentrations of trace glue in copper electrolyte solutions, and the molecular weight distribution of the glue, and its change with time using a combination of the size exclusion chromatography (SEC) and the column-switching methods was developed. Trace amount of glue can be separated from a large amount of copper sulfate and sulfuric acid in the electrolyte solutions by pretreatment of the SEC resin column. Then, only a fraction containing the glue could be introduced into an analytical column by the column-switching technique, and the determination of concentrations of glue and the molecular weight distribution of the glue could be analyzed. This method was applied to electrolyte solutions containing mg L^-1 level glue to determine concentrations and molecular weight distributions of the glue of molecular weight larger than about 2, 500.
Degradation behavior of the glue in the electrolyte solutions was also investigated. The velocities speed of the hydrolysis reaction are depended on the concentrations of sulfuric acid. By the temperature dependency of the hydrolysis reaction rate constant of glue, the apparent activation energy of hydrolysis was estimated to be 65kJ/mol using an Arrhenius plot.

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The scratching properties of DLC films containing various metals such as titanium, molybdenum and iron were investigated. These films were deposited on Si substrate by using magnetron radio frequency sputtering. High pure metal/graphite combined plates having area ratios of 1/8, 1/16 and 1/32, were used as targets in order to change the metal content of the film. The properties of the film were examined by means of a nano-indentation hardness tester utilizing an atomic force microscope, and an oscillating type scratch tester with simultaneous AE detecting.
The main results are summarized as follows: (1) DLC films containing titanium and molybdenum show larger nano-indentation hardness on the average than that of DLC film without metal. In particular, titanium is an effective element to get higher hardness. On the other hand, iron contained DLC film shows lower hardness. (2) The critical loads on the scratch test are affected by species and contents of metals. Especially, the load of titanium contained DLC film deposited by using a target of 1/16 is nearly two times larger than that of DLC film without metal. (3) Observation showed that many parts of the DLC film without metal wave damaged during scratching, however, there were no damaged parts for titanium contained film due to a higher adhesive strength. (4) Addition of titanium to a DLC film tends to increase the fracture size of the film in the scratching due to enhancement of the films rigidity, and increase the films hardness.

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The observation of the tunnel formed on D. C. etched {100} highly ordered aluminum and analysis of the tunnel shape have been performed by using the oxide replica method. The tunnel widths (W_i) were measured as a function of the tunnel depth (l_i) for the tunnels obtained by D. C. etching in AlCl₃, HCl+AlCl₃, NaCl+AlCl₃, H₂SO₄+AlCl₃, LiCl, NaCl and KCl aqueous solutions. As has already been reported regarding HCl solution, Wi tapered exponentially with l_i, i. e., log (W_i/W₁₀)=a·l_i, where W₁₀ is the tunnel width at the depth of 10μm from the tunnel entrance, in all solutions examined in this study. In HCl+AlCl₃ solution, W_i tapered rapidly with l_i compared to the case of HCl or AlCl₃ solutions. The rapid decrease in W_i with l_i, in HCl+AlCl₃ solution was considered to be caused by the increase in the concentration of Al³⁺and Cl^- ions in the tunnel, followed by the hindrance of electrochemical dissolution of Al. On the other hand, for the tunnel obtained in LiCl, NaCl, or KCl solutions, W_i tapered with l_i, at the same rate. It was considered that Li⁺, Na⁺, and K⁺ ions play the same role in the formation of the tunnel.

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Fe-Al alloys of various compositions have been prepared by electron beam melting in a vacuum. The corrosion behavior of pure Fe and Fe-Al alloys has been investigated in a solution containing chloride ions. When pure Fe and an Fe-Al alloy make a galvanic couple in 5mass% NaCl solution, both the 33.61mass% Fe and 41.19mass% Fe-Al alloys acted as sacrificial anodes to protect the pure Fe. Conversely, the pure Fe suffered significant galvanic corrosion as a result of contact with the Fe-Al alloys such as 46.11mass%Fe-Al, 60.38mass% Fe-Al and 74.38mass% Fe-Al. The anodic dissolution of pure Fe proceeded by the hydroxide mechanism or the chloride mechanism in both the (xNaCl+yHCl) and (xHClO₄+yHCl) solutions (x+y=4.50kmolm^-3). On the other hand, the anodic dissolution of both the 33.61mass% Fe and 60.38mass% Fe-Al alloys could be interpreted by the chloride mechanism in the (xHClO₄+yHCl) solutions and low [OH^-]-(xNaCl+yHCl) solutions (logC_H⁺>0). In the high [OH^-]-(xNaCl+yHCl) solutions (logC_H⁺<-0.5), the inhibition effect of OH^- ions on the anodic dissolution was weak for the 33.61 mass% Fe-Al alloy, whereas a significant decrease was observed in the anodic dissolution current of the 60.38mass% Fe-Al alloy, which may be caused by passivation.

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Superconducting Bi-Sr-Ca-Cu-O thin films with thicknesses of 30nm and less than 10nm were synthesized by using single-target magnetron sputtering and optimizing the heat treatment conditions. Cross-sectional high-resolutional transmission electron microscopy revealed that a 4nm-thick thin film consisted of a set of half-unit-cell layers of the Bi 2223 (High-T_c) and Bi 2212 (Low-T_c) phases. These film specimens were irradiated with 100keV Ar, O and N ions at very low temperature (30K), and subsequently annealed at relatively low temperatures (1003-1117K). As a result, zero-resistance transition temperature (T_{c, 0}) increased for both 30nm-and 4nm-thick thin films. Especially, for the 4nm-thick thin film, the initial T_{c, 0} of 78K was improved to 88K, approaching the T_{c, 0} of high-T_c phase. And the introduction of the pinning center was confirmed by the Ar ion implantation for the 4nm-thick thin film. It was concluded that the modification mechanism by the ion beam is based on prior atomic displacement and channeling in the cascade with the volume which is equivalent to the unit cell of the Bi system superconducting phase.

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