The surface improvement of Nb to improve the high temperature oxidation resistance was carried out by Al electrodeposition using the molten salt as an electrolyte. Electrolysis of Al was conducted using potentiostatic polarization method at constant potentials in an equimolar NaCl-KCl melt containing 1∼5 mol%AlF₃ at 1023K. The mass of electrodeposited Al increased with a decrease in polarization potential. Deposits formed at -1.3∼-1.6V (vs. Ag/Ag⁺ (0.1)) consisted of hemispherical Al phase and lamellar Nb-Al alloy phase. The alloy phase consisted of NbAl₃. Niobium covered by the Nb aluminide was more resistant than bare niobium to high temperature oxidation at 1273K for 10.8ks in air.

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Complexes composed of rice husks ash (RHA) and β-cyclodextrin (CyD) polymer (CRP) was synthesized as endocrine-disruptors (EDs) removal. TG-DTA, IR, and SEM analyzed the chemical and physical properties of CRP. The CD polymer (CP), which has intricate surface and cavities inside, were made effectively in the presence of RHA. RHA itself was changed to be a porous silicic acid during formation of CRPs. The CP perfectly was decomposed when CP was heated up to 530°C. The complex shows high removal ability with high selectivity for Bisphenol A and Dibenzofuran from aqueous solution. Removal rate of Bisphenol A by CRP was decreased with increasing of decomposition of CRP. The CRP was completely decomposed at 600°C. Removal rate of Dibenzofuran by RHA was increased as increased a porous structure of RHA. CP mainly removes Bisphenol A, and Dibenzofuran is done by cooperation with CP and RHA units.

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New introduction of the third modularity measure to the environmental conscious product design system collaborating with the conventional first-and second-modularity measure, enables the system to be reflected from the disassembly time of the products. The disassembly operation will be commonly carried out by hand with rotation of used appliances in disassembly process, and the loss time by the rotation makes the process efficiency worse. Then the introduction of the third modularity measure will be very important to evaluate the design in circulatory society promoting reuse of parts and recycle of materials by the way of disassembling.
For the illustration of the efficiency of the third modularity measure, the demonstrative experimental results of the disassembly time have been shown by making use of the trial on wooden boxes assembled by screws.

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In a sound velocity measurement in solid, the properties of electrical source and ultrasonic transducer bonded to a solid material become the error sources. In this paper, the error sources are estimated from the simulation using transmission line model of a measurement system and their experiments. A novel method for correcting the measured values of sound velocity by a numerical fitting is suggested. The usefulness of our method is demonstrated by comparing with other methods. Sound velocity measurement with the accuracy better than 1% without regard to the electrical and mechanical effects or bonding layers effects have been successfully accomplished.

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This study examined changes in the crystal structure, the surface morphology and the crystal orientation of electrodeposited film that is extracted from the negative electrode using Au pre-coating and the dispersed plating method that adds colloidal silica (SiO₂ suspension) as a dispersant to a copper sulfate electrolytic bath. Because of silica dispersion and Au pre-coating, the crystal particles on the film became fine and made uniform, and the number of particles also increased. In addition, the hardness of copper electrodeposited film rose by around 15% because of the dispersion effect of colloidal silica. Furthermore, planes (111), (200) and (311) of X-ray diffraction pattern on the copper electrodeposited film that dispersed colloidal silica almost disappeared, so the preferred orientation changed from plane (111) to (110).

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In order to improve the high-temperature wear resistance of white cast iron, a cermet powder layer mixed with Ni and/or Cr powder was inserted by molten 27 mass% Cr white cast iron. The microstructures of surface and vertical cross-section of the inserted layer were examined to investigate castability of the molten cast iron. High-temperature wear resistance of the inserted layer was examined by means of a high-temperature compressive impact fatigue test. The results obtained are as follows. (1) The inserted layer with 50 vol. % Ni powder or 25 vol. % Ni and 25 vol. % Cr powder shows satisfactory metallographic structure, though the inserted layer with 50 vol. % Cr powder includes some micro pores and voids. (2) The wear resistance decreases with increasing temperature for whole the inserted layers. The impact fatigue strength of the layer with 50 vol. % Cr powder is highest in whole the inserted layers at higher temperature side. (3) However, the inserted layer with 50 vol. % Cr powder shows many cracks connecting with the micro pores and voids after the impact fatigue test. Therefore, it is important to make an inserted layer without any micro pores and voids by using smaller sized cermet powder.

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The fluidity of melt formed in the iron ore sintering process seems to be an important factor for agglomeration of raw mixtures, since the formed melt plays the role of bonding the un-fused coarse iron ores. In the present study, sintering experiment was conducted in order to find the optimal particle size of fine iron ore for maintaining the fluidity of melt under the condition with low slag ratio and a large amount of limonite ore in the raw mixtures. As the results, it was found that the fluidity of melt lowered by decreasing the slag ratio and by increasing the amount of limonite ore in the raw mixtures. Furthermore, the optimal particle size of fine iron ore to maintain the fluidity was found to be different depended on the slag ratio in the raw mixtures and the combined water content in the iron ore.

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The electrical conductivity, density and viscosity of acidic zinc sulfate solutions containing magnesium and manganese sulfates for zinc electrowinning were measured. The concentrations of the sulfates were selected from 0 to 3.0 mol/l for H₂SO₄, ZnSO₄ and MgSO₄, and 0 to 0.2 mol/l for MnSO₄. The temperature was between 303 and 323 K. The effects of alcohol additions such as methanol, ethylene glycol and glycerin to the acidic zinc sulfate solutions were also investigated.
The electrical conductivity for the sulfate solutions of H₂SO₄-ZnSO₄-MgSO₄-MnSO₄-H₂O system increased with the concentration of the H₂SO₄ and with temperature. The density of the solutions increased with the concentration of sulfates, but slightly decreased with temperature. Their viscosities increased with the concentration of the sulfates and decreased with temperature.
The alcohol additions to the acidic zinc sulfate solutions had little effect on the density and viscosity. Nevertheless, the electrical conductivity of the solutions decreased with the concentration of the alcohol additions.

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During the hydrometallurgical extraction process of zinc, the elimination of chloride ions from the electrolyte is an important issue, because the contamination of the anode by chloride ion promotes the dissolution of Pb from the anode and raises the Pb content in the zinc cathode.
In this study, two fundamental investigations were carried out. One involved the anodic oxidation behaviors of zinc sulfate solutions, while the other was concerned with the elimination process of chlorides ions as precipitations by adding copper powder to the solution.
The concentration of chloride ion was reduced to about 50 ppm by electrolytic oxidation using Pb-alloy anodes (Pb-Ag and Pb-Ag-Ca). However, the rate of decrease in the chloride ion concentration was not very rapid when using the Pb-alloy anodes compared when using catalytic activated anodes (Pt, Ti/RuO₂).
Chloride ions can be removed as CuCl by the addition of copper powder. However, it was found that the presence of a large amount of copper ion [Cu²⁺] in the solution was required for the more effective elimination of the chloride ions.

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An empirical method has been proposed to predict the polarizability of non-polar and polar compounds using the critical properties. Several rare gases, hydrocarbons, inorganic gases, halogenated compounds, and oxygenated compounds were studied. A linear relationship is found between their polarizability volumes and the ratios of critical temperatures and critical pressures except for a few compounds.

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