We have developed highly durable IrO₂-Ta₂O₅/Ti electrodes as an oxygen evolution anode in electrogalvanizing lines (EGLs). The morphological and compositional changes of the IrO₂-Ta₂O₅ coating during anodic electrolysis have been investigated in order to improve the durability of the electrode in commercial EGLs. Based on the experimental findings obtained, the deterioration mechanism of the coating layer and the dominant factor to determine the electrode lifetime were examined. A key point to prolong the lifetime is the corrosion inhibition of the titanium substrate, which is induced by the penetration to the coating layer. The densification of the coating layer and the formation of a corrosion-resistive interlayer between the coating layer and the titanium substrate have successfully achieved the improved durability. The performance of the advanced IrO₂-Ta₂O₅/Ti electrode is shown.

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A reaction model for generation of an optically active state was studied to elucidate the necessary conditions for the appearance of a perfect optically active state, in which one of the enantiomers disappears completely. The reaction model contains multiple states and a perfect optically active state emerges only when the concentration of the enantiomer in one of the multiple states becomes zero. It has been considered that perfect chiral selection should have happened before the appearance of a primitive living system, and therefore, it might be significant to constitute a reaction model for such systems.

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A new reaction model for generation of enantiomers consisting of the most well-known chemical oscillation model, Brusselator, was introduced and its behavior was studied. As Brusselator contains a double state, there can exist a steady state of L≠D, where L and D represent the concentrations of the enantiomers of a certain chiral compound. Therefore, when L=D and L≠D steady states are unstable and stable respectively under a certain condition, the optically active state(L≠D) emerges spontaneously. As many chemical oscillation system contain a multiple state, it was suggested that a chemical oscillation system including stereoselective and autocatalytic processes could be a probable reaction system for chiral symmetry breaking.

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Defluorination of C9 petroleum resin was carried out over noble metal and metal oxide catalysts with fixed-bed reactor. Under hydrogen atmosphere, Pt-alumina catalyst decomposed 60% of fluorine compounds at 225°C. Under nitrogen atmosphere, titania catalyst showed higher activity(70%) without the decomposition of petroleum resin.

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It has been revealed that iron(III) complex containing methyltrioctylammonium chloride(MTOAC;RR₃'NCl, R=CH_3-, R'=C₈H_17-), RR₃'N[FeCl₄], was decomposed by light. On this study, the authors explore the photolysis of MTOAC-Fe(III) complex, MTOA[FeCl₄] during the extraction procedure from iron(III) hydrochloric acid solution with extractants in benzene. It was deduced that dihexyl sulfide(DHS;R₂''S, R''=C₆H_3-) accelerated the photolysis, and that the photolysis was suppressed with the increase of MTOAC concentration. The effect of oxygen during the above procedure and the electronic spectra in aqueous phase suggest that complex MTOA[FeCl₄] was reduced to iron(II) species through decomposition and was then gradually re-oxidized to iron(III) by air upon standing. Triisobutylphosphine sulfide(Cyanex 471X; R₃'''PS, R'''=i-C₄H_9-), which is the neutral sulfur-containing extractant, also showed the same behavior with DHS for the photolysis of the complex. The photolysis mechanism was discussed based on these results.

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Active carbons were prepared from such low-rank coals as brown coal(Yallourn, Australia; C 64%, Ash 1.4%) and weathered coal(Inner-Mongolia, China; C 54%, Ash 19%) with a relatively large quantities of NaOH or KOH(alkali ratio to coal 2-2.5) under a lower temperature(773-973K) than the conventional steam activation(1173-1273K). For instance, active carbons with specific surface area of more than 1000m²/g were obtained with high yields(33-36%), when weathered coal was activated by NaOH(ratio 2.5-3.0) at 973K.
The effect of alkali could be improved significantly by pre-heating(773K) of coals, affording the active carbons with higher values specific surface area(1300m²/g) at 823K. This would be due to that the pre-heating of the coals decreased with the degree of consumption of alkali with carbon dioxide generated by the decarboxylation during the activation process.
The removal of ash, especially silica in the weathered coal, was performed easily by this method by washing the final product. The ash content of the active carbon from weathered coal was at least 4%, while it was almost nil for the product from brown coal.

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The development of standard material to judge cell-culture technique and cell-response is requested in cytotoxicity testing methods for biocompatibility of biomaterials. Vanadium or nickel standard solutions used in inductively coupled plasma(ICP) analysis were added separately at appropriate concentrations to Eagle’s medium and α-modified Eagle’s medium(α-medium). Vanadium or nickel particles were independently extracted in ultra-pure water and Eagle’s medium. Then, these extracted solutions were added to fresh Eagle’s and α-mediums. Murine fibroblast L929 cell and murine osteoblastic MC3T3-E1 cells were respectively cultured with these Eagle’s and α-mediums. The effect of the vanadium and nickel ions in the standard solution used in ICP analysis on cell growth were good accordance with that of the extraction using vanadium and nickel particles. Therefore, it was thought that vanadium or nickel standard solutions used in ICP analysis could be applied as a standard material in biocompatibility tests using cultured cells.

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Studies have been conducted on the sorption equilibria of Zn(II), Mn(II), Cd(II), Cu(II), Co(II) and Sm(III) from aqueous media at low acidities by a macromolecular resin impregnated with 2-ethylhexyl hydrogen-2-ethylhexylphosphonate(2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester, EHPNA, HR). Sorption equilibria of these metallic ions(Mⁿ⁺) on the macromolecular resin impregnated with EHPNA(EHPNA-impregnated sorbent) can be expressed by a simple ion exchange reaction which is different from solvent extraction with EHPNA.

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Mn++nHR⇄MRn+nH+

The equilibrium constants Kex of Zn(II), Mn(II), Cd(II), Cu(II), Co(II) and Sm(III) were found to be 6.25×10^-3, 4.0×10^-5, 4.0×10^-5, 3.1×10^-5, 2.2×10^-6kg-sor dm^-3 and 7.69×10^-3(kg-sor)² dm^-6, respectively.
The separation factors defined by the ratios of the equilibrium constant of Zn(II)/ Cu(II), Zn(II)/ Mn(II) and Sm(III)/ Co(II) were 202, 156 and 3495, respectively.
The mutual separation from the binary metal solutions of Zn(II)/ Cu(II), Zn(II)/ Mn(II) and Sm(III)/ Co(II) using the EHPNA-impregnated sorbent has also been studied in a column operation. It was found that the selective separation is attained satisfactorily by use of the sorbent.

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Acidic deposition was observed semimonthly using bulk sampler on the coast of the Okhotsk Sea in Hokkaido from June 1994 to March 1997. The observation shows that the precipitation amount and the concentrations of major ions in precipitation are less than the means of these over most of observation sites in Japan. Especially, the depositions of the ions are 30 to 40percent of the mean values of these means.
The precipitation pH varies from 4.7 to 5.7 though the variation of reciprocal logarithm of input acidity, that is pA_i, was relatively small, so that the molar fractional acidity defined as [H⁺]/(2×[nss-SO₄^2-]+[NO₃^-]) varied from 0.05 in spring to 0.4 in summer. This may have resulted from the neutralization of the acidified precipitation with ammonia and calcium compound in atmosphere.
The monthly depositions of nss-SO₄^2-, NO₃^- and NH₄⁺ were found to depend upon the precipitation in manner which the depositions proportionally increase with monthly precipitation in the range of the precipitation less than 120mm/month whereas the depositions of nss-Ca²⁺ and the ions originated in sea salt are independent of precipitation. Especially, it is found that the wind velocity may be important factor for the deposition of the ions originated in sea salt.

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Precipitation samples(n=188) were collected in Higashi-Hiroshima, Japan during September 1995-March 1999, and the concentration of organic acids such as formic, acetic and oxalic acids was measured by ion chromatography. Volume weighted average concentrations of organic acids in precipitation samples were 3.4μM for formic acid, 2.3μM for acetic acid and 0.24μM for oxalic acid, respectively. Volume weighted average annual depositions of these acids for three years(1996-1998) were 4.8mmol m^-2 year^-1 for formic acid, 3.3mmol m^-2 year^-1 for acetic acid and 0.32mmol m^-2 year^-1 for oxalic acid, respectively. Seasonal variations of volume weighted average concentrations and deposition rates were showed to be high in spring and summer seasons, and low in autumn and winter seasons, probably due to the variation of photochemical activities corresponding to solar intensity. Organic acids contributed 7.9%(in the range of 0.79-21.3%) of total acidic species(non-seasalt sulfuric acid+nitric acid+non-seasalt hydrochloric acid+organic acids) in volume weighted average and the percentages exhibited the same seasonal variations as the concentrations and deposition rates. The result of linear regression and principal component analyses indicate that organic acids well correlated with man-made acidic species such as nitrate and non-seasalt sulfate. Thus, organic acids in precipitation collected in Higashi-Hiroshima may originate mostly from anthropogenic sources, via the direct emission and/or formed through photochemical reactions of precursors like hydrocarbons and aldehydes. The calculated equilibrium concentrations of gas-phase formic and acetic acids are comparatively in good agreement with reported gas-phase concentrations measured in Higashi-Hiroshima.

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