In the present research, anodizing and pore-widening treatment of aluminum as a surface treatment was conducted to generate nanopores, and a corrosion inhibitor was inserted into the nanopores. Then self-healing ability was evaluated. Pure aluminum was used as a specimen, and the pore size was controlled by changing the voltage to 10-20 V. Sodium benzoate as corrosion inhibitor was inserted in nanopores in various anodized aluminum specimens. The insertion amount of the corrosion inhibitor in aluminum anodized at 12 V for 60 min was high. The insertion amount was further increased by pore-widening treatment. A polymer coating was applied to prepared anodized aluminum, and a scratch exposing substrate was generated on the specimen. Polarization resistance of the specimen in corrosive solution was measured by electrochemical impedance method for 24 h. Aluminum anodized at 12 V for 60 min and treated by pore-widening for 12 min showed the highest resistance. The mechanism of self-healing was analyzed by zeta potential measurement. Hydroxide ion is generated around the defective part by the cathodic reaction of corrosion, and the pH of the solution increases. The corrosion inhibitor in nanopores of anodized aluminum is desorbed, resulting in the formation of healing film on defective parts of the specimen.

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We studied the application of a potential noise technique to monitor the initiation of pitting in a salt manufacturing process with bittern. The corrosion potential and its fluctuations, or the potential noise of a SUS316 sample-electrode were continuously measured every 0.5 s in a simulated bittern. During the measurement, an argon-mixed gas with 0.1 ％, 1 ％ or 10 ％ of oxygen or indoor air（oxygen concentration: 21 ％）was injected into the test solution of the simulated bittern. A change in the corrosion potential as well as the frequency of the potential noise was measured by changing the solution temperature stepwise within a range from 60 ℃ to 100 ℃. The waveforms of the measured potential noise were either the RD-I or the RD-II type, which were the characteristic waveforms for the potential noise generated while a metastable localized-corrosion was formed under an oxidizing environment. The frequencies of the potential noises increased with the oxygen concentration of the injected gases at the same temperature. From the above results, it was considered that the initiation of pitting for the process units with bittern, such as evaporators and tanks, which would be caused by contamination by oxygen from air as well as an increase in solution temperature, would be monitored by measuring the corrosion potential and the potential noise on sites.

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In this study, we examined how a Mineral Mixture derived from wild plants（Plant Mineral Mixture）has a beneficial effect on the prevention and improvement of increased skeletal muscle insulin resistance in type 2 diabetic mice. Type 2 diabetic mice were obtained by injecting intraperitoneally streptozotocin（70 mg/kg BW）and nicotinamide（240 mg/kg BW）in normal slc/ddy male mice. In intact（control）male mice fed a commercial diet, type 2 diabetic mice fed a commercial diet with and without Plant Mineral Mixture at the level of 100 mg/kg body weight/day for 3 weeks, changes in body weight, the uptake rate of 2-deoxy-D-glucose（2DG）, PI3 kinase, Akt kinase and AMP kinase activity in the biceps femoris muscle were investigated. An intraperitoneal glucose tolerance test is also designed to determine clearance of an intraperitoneally injected glucose load from the body. Type 2 diabetic mice indicated a significant lower body weight and an extended recovery period of the blood glucose concentration in the glucose tolerance test in comparison with those of the control. Decreases in the uptake rate of glucose and the activity of PI3 kinase and Akt kinase in the biceps femoris muscle were also evident. In the type 2 diabetes mice treated with the Plant Mineral Mixture, on the other hand, except for body weight, the uptake rate of glucose, the activity of PI3 kinase and Akt kinase in the biceps femoris muscle returned to those of the control. The recovery period of the blood glucose concentration in the glucose tolerance test was not different between the control and the type 2 diabetic mice treated with the Plant Mineral Mixture. These data suggest that oral administration of the Plant Mineral Mixture contributed to preventing and improving skeletal muscle insulin resistance through the promotion of translocation of GLUT4 in the muscular cells, when treating type 2 diabetic mice.

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We prepared novel cation exchange membranes（CEMs）by ion-track grafting of ethyl p-styrenesulfonate（EtSS）into a base fluoropolymer film and subsequent hydrolysis of EtSS units. At the ion-beam fluence of 1.0×10⁹ ions/cm², the grafting degree of EtSS was controlled in the range of 13.4 ％ - 75.1 ％ by changing the grafting time. The obtained CEMs showed the ion exchange capacity（IEC）ranging from 0.38 to 1.70 mmol/g. The water content of the CEMs increased with an increase in IECs. The membrane resistance of the CEM with the IEC of 1.70 mmol/g was 0.18 Ω cm², which was only around one tenth of that of a commercial CEM, Neosepta® CMX.

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The Analytical method for basic magnesium carbonate（BMC）and calcium carbonate（CC）as neutralizing titration was conducted to review conditions. It is determined by adding an excess of acid solution, volatilizing the carbonate ion as carbon dioxide, heating to allow the carbon dioxide to escape, and then back-titrating the excess acid solution with sodium hydroxide. As an acid solution, sulfuric acid was selected, and the heating condition was 75 to 90 ℃, for half an hour. Mixed indicators of methyl red and bromocresol green was easier to see at the end point. Recoveries of added carbonates were CC, 99.98 ％ and BMC, 96.31 ％. The result on edible salt was statistically compared to results determined using conventional EDTA chelate titration method.

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