Investigations were conducted to determine optimum bath compositions for the anodizing of aluminum, and the properties of the coatings obtained were investigated using organic (choline-fluoride base) alkaline baths containing ammonium fluoride and organic acid salts.
In the anodizing of aluminum in baths containing organic acid salts ((NH₄)₂C₂O₄, (NH₄)₂C₄H₄O₆ and (NH₄)₃C₆H₅O₇) uniform films were obtained, but in baths without these additives and with added ammonium acetate, non-uniform films were formed. The thickest films (about 15μm) were formed by anodizing for 30min at 20°C at a current density of 2A/dm² in 0.2mol/L cholins solution containing 0.2mol/L ammonium fluoride and 0.1mol/L ammonium tartrate or in 0.2mol/L choline solution containing 0.1mol/L ammonium fluoride and 0.2mol/L ammonium citrate.
The film formed in 0.2mol/L choline solution containing 0.3mol/L ammonium fluoride and 0.1mol/L ammonium oxalate showed a high hardness (about 28 in Marten's scratch hardness test, load 50gf) and high corrosion resistance. It was found by SEM observation that pores of films prepared in baths containing ammonium citrate were about 50∼100nm in diameter, while those prepared in baths containing ammonium oxalate measured only about 40nm.

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In this paper, the anodizing of aluminum was investigated using water-soluble aromatic amine (benzylamine) to compare with aliphatic amine. Investigations were conducted to determine optimum bath compositions for the anodizing of aluminum in organic alkaline baths (benzylamine-fluoride base) involving ammonium fluoride and organic acid salts (HCOONH₄, CH₃COONH₄, (NH₄)₂C₂O₄, (NH₄)₂C₄H₄O₆, (NH₄)₃C₆H₅O₇). In the case of anodizing in baths containing organic acid salts, uniform films were formed, but non-uniform films were formed in baths without these additives. The thickest film (about 8μm) was formed in a 0.05mol/L benzylamine bath containing 0.1mol/L ammonium fluoride and 0.3mol/L ammonium acetate or in a 0.2mol/L benzylamine bath containing 0.1lmol/L ammonium fluoride and 0.2mol/L ammonium tartrate by anodizing for 30min at 20°C with a current density of 1A/dm². The film formed in the 0.2mol/L benzylamine bath containing 0.1mol/L ammonium fluoride and 0.1mol/L ammonium tartrate was the hardest (Marten's scratch hardness test, load 50gf, about 13) and the film formed in 0.1mol/L benzylamine bath containing 0.1mol/L ammonium fluoride and 0.1mol/L ammonium citrate showed the highest corrosion resistance. SEM observation found that pores of films prepared in back containing ammonium acetate were about 30∼50nm in diameter, while these prepared in baths containing other organic acid salts were about 50nm.

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Bath compositions suitable for the anodizing of aluminum were investigated in organic alkaline baths (hydrazinefluoride base) with additions of ammonium fluoride and organic acid salts In baths containing organic acid salts (CH₃COONH₄, (NH₄)₂C₂O₄, (NH₄)₂C₄H₄O₆ or (NH₄)₃C₆H₅O₇), uniform films were formed but in baths without these additives the films were not uniform The films that were thickest (about 15μm) and hardest (about 23 as Marten's scratch hardness under load of 50gf) were obtained in a 0.1mol/L hydrazine bath containing 0.1mol/L ammonium fluoride and 0.05mol/L ammonium citrate by anodizing for 30min at 20°C with a constant current density of 2A/dm² SEM observation of the film surface showed that the films formed in baths containing ammonium oxalate or ammonium citrate had larger pores (500∼1000Å) than those formed in baths containing ammonium acetate or ammonium tartrate. It is concluded that the formation of large pores is caused by the dissolution of cell walls at higher voltages (about 110V)

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The anodizing of aluminum was investigated in propylenediamine-fluoride solutions containing organic acid salts. Using a 0.1mol/L propylenediamine solution containing 0.2mol/L ammonium fluoride, uniform films about 10μm thick were formed, while in the above bath with the addition of organic acid salts (CH₃COONH₄:0.05mol/L, (NH₄)₂C₂O₄:0.05mol/L, (NH₄)₂C₄H₄O₆:0.2mol/L, (NH₄)₃C₆H₅O₇:0.1mol/L), thick films (about 14∼17μm) were obtained. Marten's scratch hardness tests (load 50gf) showed that the hardest film (20.2) was obtained in the bath containing ammonium acetate. The films formed in the baths containing organic acid salts yielded nearly the same results (75∼80sec) in alkali dropping tests. SEM observation showed that the surface of films formed in baths containing ammonium acetate or ammonium oxalate consisted of a mixture of small (approx. 300Å) and large (approx. 1000Å) pores.

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We studied the formation of anodic oxidation coating on aluminum in a mixture bath of aliphatic monoamine and organic acid salts without ammonium fluoride. Aluminum was anodized in aliphatic monoamine baths (methylamine, ethylamine, propylamine, and buthylamine) containing organic acid salts (formic, acetic, oxalic, tartaric, and citric acid salts), at a bath temperature of 20°C, and a current density of 1A·dm^-2. Anodized films formed in monoamine baths containing ammonium tartrate and triammonium citrate. Film was found to be thinner about 4-5μm when formed in monoamine baths containing ammonium tartrate and triammonium citrate than film when formed in baths containing ammonium fluoride about 7-8μm. SEM observation of film showed that film formed in mathylamine baths containing ammonium tartrate or triammonium citrate had a smoother surface than that formed in other amine baths containing ammonium tartrate or triammonium citrate. The smooth surface was apparently formed by dissolution of the film surface in an amine alkaline bath. (tartrate bath pH=11.4 or citrate bath pH=11.7). Pore diameters of film formed in amine baths containing tartrate and citrate were about 25-45nm.

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In this paper, the anodizing of aluminum was investigated using isopropanolamine (1-amino-2-propanol) for comparison with ethanolamine and choline. Studies were conducted to determine the optimum bath compositions for anodizing aluminum in isopropanolamine alkaline baths involving ammonium fluoride and organic acid salts (HCOONH₄, CH₃COONH₄, (NH₄)₂C₂O₄, (NH₄)₂C₄H₄O₆, (NH₄)₃C₆H₅O₇, (CH₂)₄(COONH₄)₂). Uniform films were formed when anodizing in baths containing organic acid salts, but non-uniform films were formed in baths without these additives. The thickest film (about 8μm) was formed in a bath containing ammonium acetate and ammonium tartrate by anodizing for 30min at 20°C with a current density of 1A/dm². Films formed in baths containing ammonium tartrate or tri-ammonium citrate were the hardest (Marten's scratch hardness test, load 50gf, about 19) while films formed in baths containing tri-ammonium citrate or ammonium adipate showed lower corrosion resistance. SEM observation found that films prepared in baths containing monocarboxylic acids salts had a few pores about 25-40nm in diameter in addition to those with diameters of 15-20nm, while these prepared in baths containing other organic acid salts had pores about with diameters of 30-40nm.

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 Numerous fermented milk products containing probiotic lactobacilli have recently been commercialized in Japan. Certain probiotic lactobacilli grow slowly in milk. Therefore, some products are produced by co-culture with ordinary yogurt starter bacteria after the addition of sufficient amounts of separately propagated viable probiotic cells.
 Only a limited culture media for the test purpose of lactobacilli are commercially available (for example MRS broth), but the media for large-scale propagation of viable cells which are able to be used as food additive are not available. The manufacture of a low -priced and preferred novel medium for lactobacilli was, therefore, attempted using cheese whey powder as a starting material. Heat labile proteins in cheese whey were removed by pre-heating, then the whey solution was complemented with casein-protease hydrolyzate, glucose, yeast extract of food additive grade, Tween 80 and minerals. The growth test was mainly performed using human originated Lactobacillus acidophilus strains. The growth of several lactobacilli in the finally attained medium (WIM broth) composed of 7% deproteinized cheese whey, 1% glucose, 0.3% yeast extract, 0.1% Tween 80 and minerals, was comparable to MRS broth. The modified WIM broth which Tween 80 was replaced with decaglycerol-monooleate and composed of only food additive grade minerals was also a prominent medium for large-scale propagation of viable cells for the purpose of adding into several food products.

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  Radioactive cesium has strongly bound soil as time proceeded, which could not be cleaved in mild condition. We have found that serial treatment of ammonium citrate solution and ionic liquid removed radioactive cesium from soil effectively. The sequence of the treatment is crucial, since inverse serial treatment or mixture of two kinds of solution did not show such an effect, which suggested that ammonium citrate unlocked trapped cesium in soil and ionic liquid solved it. We also found that repeating serial treatment and prolonged treatment time additively removed cesium from soil.

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Ni-W alloy plating has been considered for application to various industrial fields as a substitute for hard Cr plating. However, by plating conditions, the plating crack on Ni-W alloy film might occur and cause difficulties in industrial use. In this study, we elucidated the plating crack behavior of Ni-W alloy films with various W contents. We also investigated the influence of the internal stress of Ni-W alloy film on the plating cracks. Results show that the number of the plating cracks changed by W content in the range of 27.3-51 wt%W. At approximately 40 wt%W, plating cracks did not occur. Moreover, the change of the internal stress of Ni-W alloy film in the range of 30-46 wt%W showed a convex-downward curve against the W content, which indicated the least internal stress in approximately 40 wt%W. Furthermore, the influence of the misfit between the Ni-W alloy film and that substrate was small, which suggests that the internal stress of the film itself changed. Therefore, the internal stress was regarded as a direct factor affecting the plating crack. Furthermore, from results of X-ray diffraction patterns of Ni-W alloy films with various W contents, the change of the internal stress was inferred to have resulted from the change of the crystalline state.

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Cause of the strange osteomalacia “itai-itai” disease which appeared in the Jinzu River basin, Toyama Prefecture, was concluded to be a public hazard induced by cadmium in the waste water from a mine.
In Annaka City, Gunma Prefecture, where the largest zinc refinery of Japan is located, many samples of agricultural products and soils were collected in October 1968 and June 1969 and analyzed to verify actual conditions of pollution by the refinery.
As a result, it was found that the content of cadmium and other metals in mulberry leaves for silk worm or wheat flour is remarkably related to the distance (220-2, 500m) from the refinery chimney, and further, that the content of cadmium and other metals is remarkably higher in leaf vegetables such as cabbages (Cd 60-3ppm, Zn 7, 000-300ppm, Pb 370-4ppm in dry matter) compared with root vegetables (potato, carrot, radish), fruit vegetables (tomato, squash, eggplant), or cereals (barley, wheat, rice, corn). Nevertheless, the pollution of the latter has to be considered. Thus, it was made clear that principally the hilly regions are polluted by metal contained air, and that lower rice field regions are also affected by polluted air as well as waste water.

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我々は歯科治療器具の高機能化を目指し，電鋳法を用いて任意の3次元微細構造を作製する研究を実施している．歯科治療器具は歯を削ることが可能な高い強度を有している必要があるので，作製する材料としてWとNiの合金を選択した．本研究では，直径30µmの銅細線を種電極としてW-Ni合金のマイクロチューブを作製し，その機械強度を評価することで，W-Ni合金の歯科治療器具材料としての有用性を検討した．

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The purpose of this investigation was to study electroless Au plating by displacement reaction from citric acid bath (106 mM (NH₄)₃C₆H₅O₇ + 14 mM C₁₀H₁₄N₂Na₂O₈ 2H₂O + 5 mM KAu(CN)₂) containing sodium dodecyl sulfate (SDS) or polyethylene glycol (PEG) by means of electrochemical method, scanning electron microscopic observation, measurement of adhesive strength between Au and Ni films, etc. SDS accelerated the oxidation reaction of Ni and the degree of corrosion for Ni film during Ni/Au displacement reaction was large in the presence of SDS. On the other hand, PEG inhibited the oxidation reaction of Ni and the degree of corrosion was small in the presence of PEG. Electroless Au film which has a strong wire pull strength and adhesive strength was obtained from a bath containing PEG by displacement reaction.

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The effects of electrolyte species and electrolytes combination during two-step anodization of anodic oxide films formed on aluminum in relation to the crystallinity and dielectric properties as an electrolytic capacitor was investigated. Aluminum substrate was pre-treated by dipping in boiling water to form hydration layer. Anodic films were annealed at 500°C after the first anodization. The CV (capacitance C multiplied by withstand voltage V of the film) of the films formed by the second anodization in borate was higher than that of the films formed in the same electrolyte of the first anodization. The CV increased due to the improvement of crystallinity by using borate for second anodization in the following order: salicylate<succinate<tartrate<phosphate<citrate<adipate<borate. When phosphate or organic electrolytes were used at the second anodization, notable spike noises were found. However, the spike noises were significantly suppressed when borate was used as the second anodization.

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近年の半導体デバイスは多層構造と配線の微細化による高集積化に伴い高性能化しており，配線のさらなる多層化を行うためには各層間の十分な平坦化が必要となる．そこで平坦化加工技術として, 筆者らはポリグリセロールで修飾したナノダイヤモンド（Polyglycerol-functionalized Diamond Nanoparticles; ND-PG）を研磨砥粒とした新たな化学機械研磨（CMP）技術を提案している. ND-PGは，粒径が小さい，水分散性がよい，金属元素を含まないなど，CMP研磨砥粒として望ましい性質を持っている. 本研究ではND-PGを用いたスラリーを試作し，配線金属の銅に対して研磨実験を行い，ND-PG砥粒を用いた研磨によってナノメートルオーダの平坦度・平滑面を実現した.

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This study developed surface finishing methods to prevent corrosion of electropolished SUS316L stainless steel in isopropyl alcohol（IPA）. For this development, immersion corrosion tests in 99.7% IPA and anodic polarization tests in 0.15 kmol･m^－3 HCl were conducted using electropolished SUS316L specimens passivated with 30% HNO₃, 0.1 kmol･m^－3 Na₂MoO₄-containing 30% HNO₃, 3.5% H₂O₂ and 0.98% H₂O₂- containing 8% citric acid. Identical tests were also applied to specimens heated to 200－450 ℃ after passivation treatments. Corrosion morphologies of these specimens in 99.7% IPA exhibited pitting. Pit densities and corrosion rates of these specimens in 99.7% IPA showed good correlation with pitting potentials in 0.15 kmol･m^－3 HCl. Judging from the obtained values of pit densities and pitting potentials, specimens passivated with 30% HNO₃ or 0.1 kmol･m^－3 Na₂MoO₄-containing 30% HNO₃ showed very good corrosion resistance against IPA corrosion. Heat-treatment at 200 ℃ after surface finishing using 30% HNO₃ and 0.1 kmol･m^－3 Na₂MoO₄-containing 30% HNO₃ increased corrosion resistance against IPA. However, heat-treatment at temperatures higher than 350 ℃ decreased the corrosion resistance.

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