SANYO Electric Co., Ltd. led the world by successfully marketing nickel-metal hydride betteries in 1990. Because these batteries offer the same operating voltage as nickel-cadmium batteries, and more than 1.5 times higher capacity, their use is rapidly expanding. In order to refine nickel-metal hydride batteries into a marketable product, we had to overcome a number of technical difficulties, mainly in the development of hydrogen absorbing alloys, as detailed below. We used a LaNi₅-based hydrogen absorbing alloy beca use of its superior capabilities as an electrode catalyst. We then directed our efforts toward developing a material that offers both high capacity and ex cellent corrosion resistance by gradually replacing a portion of the LaNi₅ with other elements. While verifying the characteristics of these new combinations through experimental electrodes and batteries, we discovered that a MmNi_3.2Co_1.0Al_0.2Mn_0.6 alloy had the same characteristics, and later demonstrated that we could produce a high-capacity, long-life battery with that alloy. Moreover, we developed cadmium-free nickel electrode, and raise d its performance to conventional levels. We also established structural technologies by analyzing the reaction characteristics of the nickel-metal hydride batteries. The batteries that w e developed as a result of these efforts offer superior characteristics, including a 1.2-hour charge time, a 4C discharge rate, and a service life of at least 500 charge-discharge cycles. These characteristics have enabled the application of nickel-metal hydride batteries to the power sup plies of high-performance equipment such as communications equipment and computers.

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A bituminous coal carbonized at high temperature was activ ated with carbon dioxide or water vapor to form active carbon. The raw carbon consists of random mixtures of two kinds of distinct small domains mutually complicated: one is amorphous carbon being oxidized easily and the other oxidation- proof graphite crystallite. During the activation, the amorphous carbon is predominantly oxidized and micropores are formed at its sites. The density of the amorphous region was 2.05 g cm^-3, and the fraction of the domain in the raw carbon was 45 wt%. A kinetic equation was derived for the oxidation at the amorphous region assuming the adsorption of activator molecules onto the surface.

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Optical properties of an anisotropic particle suspension were studied with special reference to the transmittance relaxation that occurs upon continuous electrical activation.
The suspension investigated consisted of needle shape org anic crystals of dihydrocinchonidine hydrogensulfate ester hydropolyiodide, fluorocarbon oil as solvent, and copolymer o f neopentyl acrylate and N-(hydroxymethyl)acrylamide as dispersant. When voltage was applied to a cell containing the sus pension, light transmittance increased immediately and maximized within 0.5 s. However, upon further activation transmittance decreased gradually and tailed of in a few hundred seconds. This is called “transmittance relaxation” in this paper.
The degree and rate of transmittance re laxation changed with several factors associated with suspen sion and activation conditions. The relaxation occurred to more considerable degree and rate when crystal concentration was high and crystal size was large. So did it when frequency of alternative voltage was high. When intermittently deactivated and reactivated, greater recovery of the peak transmittance was observed at a longer deactivation time.
Particle size measurement by the orie ntation relaxation method revealed that particle grows upon the transmittance relaxation. This indicates the formation of clusters under electrostatic force around a large crystal over approximate 400 nm in size. When deactivated, the cluster disintegrated and the associated crystals dispersed uniformly, thus eventually leading to the original state of suspension. t Studies on OpticalP roperties of an AnisotropicP article Suspensionu pon Electrical Activ ation. I.

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Effective and safety phosphate binding agent for oral administration is desired for patients of renal failure. The feasibility of amorphous iron (III) hydroxide as the agent was investigated in vitro, because the toxicity of iron (III) hydroxide and Fe³⁺ ion is lower than that of Al³⁺. Amorphous iron (III )hydroxide showed large phosphate binding capacity per gram (PBC) in a wide pH range (1.5-8). In the presence of phosphate, amorphous iron (III) hydroxide was dissolved little at pH 2 corresponding to the pH value in stomach. It was considered that phosphate ions were bound to the amorphous iron (III) parti cles by ligand exchange with OH^- on the surface of particles under weakly acidic conditions, and that phosphate ion was precipitated as amorphous iron (III) phosphate under strongly acidic conditions, where iron (III) hydroxide is not stable. The molar ratio of (bound phosphate/Fe in the agent) was able to increase by controlling the composition of iron (III) hydroxide and cellulose, even though PBC decreased.

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Hydroxyapatite (HAp) whiskers, which are elongated along the crystallographic c-axis, were synthesised under hydrothermal method using citric acid. Starting HAp slurries with two different concentrations of 1.7 and 4.4 wt% were prepared by a precipitation method, and became clear solutions by adding suitable amounts of citric acid (Cit.) to dissolve HAp particles. The solutions of 1.0 dm3 were hydrothermally treated in an autoclave at a temperature from 180 to 220°C for 0, 1, 2, 3, 5 and 10 h. The crystalline phases of the products detected by powder X-ray diffractometry depended on both the concentration of HAp and the temperature and the duration of hydrothermal treatments. No HAp whiskers could be obtained from the solutions containing 4.4 wt% of HAp at any Cit./HAp ratio. They could be obtained, however, only from those of 1.7 wt% above a limited Cit./HAp molar ratio such as 14.8. In addition, hydrothermal treatment for more than 3 h at 200°C was necessary to synthesise HAp whiskers. The whiskers were from 10 to 30 pm in length and about 0.5 μm in diameter. However the weight proportion of HAp in the products rapidly decreased with the increasing that of plate-like calcium hydrogenphosphate anhydrate (DCPA: monetite) below 200°C within the first 3 h.

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An analytical method of commercial tetrafluoroethylene copolymer was investigated by high-field magnetic ¹⁹F-NMR (376.4 MHz) in their molten state at high temperatures, since the resins were hardly soluble in any solvent. Measuring conditions were optimized; the probe temperature was set to about 20°C higher than the melting point of the resin and rod form was preferable to powdered form. In tetrafluoroethylene-heptafluoropropyl trifluorovinyl ether and tetrafluoroethylene-hexafluoropropy lene copolymers, identification of 1.5 mol% of comonomers were possible. Termonomers of three kinds of ethylene-teterafluoroethylene copolymers were assigned by the proposed method and the microstruc ture of the resins were discussed. The ethylene-ethylene sequence was directly confirmed by moltenstate ¹H-NMR.

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Pentachlorophenol (PCP) was coprecipitated with a mixed hydroxide of iron (III) and magnesium at about pH 12 and extracted with 1-pentanol. A 3ml portion of 1 mol⋅ dm^-3 ir on (III)chloride solution and 6 ml of 2 mol⋅ dm^-3 magnesium chloride solution were added to a 500 ml of sample solution and pH was adjusted to 12 with sodium hydroxide to precipitate the mixed hydroxide of iron (III) and magnesium with which PCP was coprecipitated. The suspention was stirred for 60 min. After centrifugal separation, the precipitate was dissolved with 4 ml of 5 mol⋅ dm^-3 sulfuric acid, and pH of the reddish solution was adjusted with sulfuric acid to the range from 1 to 2. The total volume of the reddish solution was made up to 40 ml with distilled water and was extracted with 5ml of 1-pentanol. A small amount of sulfuric acid was added into the extract. The absorbance of extract was measured at 290 nm against 1-pentanol. PCP as low as 50 ppb could bedeter mined. NH₄⁺, Ca²⁺, CO₃^2-, SO₄^2-, BO₃^-, NO₂^-, NO₃^-, F^-, SiO₄^3- and PO₄^3- as much as 1 x 10^-3 mol dm^-3 did not interfered.

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Dimerization of 3 (2-substituted ethenyl) guaiazulenes, which have nitro group or trifluoroacetyl group as the substituent, with sodium methylate gave 5, 6-dihydrocyclopenta[ef]heptalene derivatives. The products were easily converted into 4-substituted 9-isopropyl-1-methylcyclopenta[ef]heptalenes, when they treated with formic acid or with trifluoroacetic acid. The same type of dimerization was also noted in the reaction of 3 (3-oxo-3-phenyl-1-propenyl)guaiazulene with sodium methylate, while that with potassium t-butylate afforded 9-isopropyl-1-methyl-5-phenylcyclopenta[ef]heptalene formed by intramolecular cyclization. On the other hand, tream ent of 3 (3-oxo-1-butenyl) guaiazulene with either of the bases resulted only in intramolecular cyclization. Both reactions provide a convenient synthetic route to the cyclopenta [ef]heptalene derivatives. Moreover, neither of the reactions took place in 3-styrylguaiazulene. Reaction pathways were described on the speculation that strong electron-withdrawing groups would be necessary for dimerization, though moderate ones seemed to be suited for intramolecular cyclization.

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cylation reaction of aliphatic nitro compounds (1) with acetyl chloride in the presence of glycocyamidine (2a) afforded 4 (1, 2, 4-oxadiazol-5-yl) methyl-1, 2, 4-oxadiazol-5 (4H) -one (4) and their imino derivatives (5). The reaction was applied to creatinine (2b) and 1, 3-dialkylglycocyamidine (2d-2h) to give N-methyl-N (1, 2, 4-oxadiazol-5-yl) [ (1, 2, 4-oxadiazol-5-yl)methylamine] (6) and 5-substituted 1, 2, 4-oxadiazole derivatives (9, 11), respectively. The mechanism of formation of thes e products appears to involve 1, 3-dipolar cycloaddition of nitrile oxides with imine intermediates (A, B, C, or D) which result from ³N-²C cleavage of imidazolidine ring of 2.

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Dielectric properties of nonlinear optical chromophore functionalized poly (methyl methacrylate)(PMMA) with 4-amino-4′-nitroazobenzene (DO3) have been investigated in the temperature range from 180 to 150°C. Four relaxation processes were found. Three of these relaxation processes were also observed in PMMA homopolymer. The four processes are respectively attributed to the relaxation due to absorbed moisture, the relaxation of the side chain without DO3 group, the primary relaxation of microphase with a low concentration of DO3 group, and the primary relaxation of microphase with a high concentration of DO3 group, in order of ascending temperature. Time dependence of the second-order dielectric constant |ε₂|for a sample obtained by poling DO3PMMA have been measured at various temperatures. At room temperature, the decay was slight. At 60°C and 110°C, the values of 1621 after 6 h from the end of poling decayed by 30-50% of the initial values of |ε₂|. Observed values at 60°C and 110°C was able to be described by the biexponential equation better than by KWW (Kohlrausch-Williams-Watts) equation indicating that DO3 groups exist in at least two different kinds of environment.

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Surface of calcium phosphate ceramics was modified with silane coupling reagents using reflux method. The results of thermal analyses and infrared and mass spectra suggested that surface hydroxy groups of the ceramics form covalent bonds with silane coupling reagent molecules. Regardless of the reagent species, almost the same number of organic groups was introduced when the reaction conditions were the same. The ζ potential of the modified ceramics varied with the number of the introduced organic groups. This result suggests that the cell compatibility of the ceramics can be changed by controlling the amount of the introduced organic groups.

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The effects of alkyl-chain length of alkylphosphonic acids (P_n: n= carbon number of alkyl chain) on thermochromic behavior of a fluoran dye (FD: 2' (o-chloroanilino) -6'-dibutylaminospiro[isobenzofuran-1 (3H), xanthene]-3-one) were examined. The mixture films of P_n and FD in liquid states on heating conditions were colored. In the case of the mixture films of P14-22 and FD, the solidified colored states, which were maintained at room temperature, were attained by quenching from liquid states. The slow cooling, however, resulted in the discolored states. Upon heating from the solidified colored states, the discoloration occurred at the temperature about 20°C below the melting and coloring temperature of each mixture film. With increasing alkyl chain length of phosphonic acid, the discoloring temperature was raised, and the mixture film was well discolored in heating process. On the other hand, the films of P10/FD and P12/FD did not show the stabilized colored state after quenching, and the discoloration progressed with time at room temperature. In the case of the film of P4/FD, the colored state was maintained at room temperature after quenching, but no solid film was obtained and the discoloration was not shown in heating process. We confirmed with X-ray diff ractometry and DSC of the P_n/FD films that the solidified colored films are in a lamellar structure, in which P_n and FD molecules form a certain type of supramolecule. By contrast, the discolored state is caused by fractional crystallization of phosphonic acids, decomposing the supramolecular formation by heating. A model of thermochromic mechanism is given, taking account of the supramolecular formation of P_n/FD, which is influenced by the chain-chain interaction of phosphon ic acids.

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Tetramethylammonium hydroxide (TMAH) (1) solution which was free from chloride ion was syn thesized by electrolyzing its hydrogencarbonate (11) in an electrolytic cell with a cation exchange membrane. Trimethylamine (2) and dimethyl carbonate (8) reacted in an equivalent molecular ratio, suggesting that one of the two methyl groups of (8) was incorporated into methyl carbonate salt (10) (Scheme 3).482 g (2.25mol) of the hydrogencarbonate solution (63.0%), which was free from methanol by hydrolyzing of methyl carbonate salt (10), was placed in the electrolytic cell with a cation exchange membrane (Du Pont Nafion 324) as a diaphragm and was electrolyzed by impressing 20 V for 12 h.626g of 30.7% TMAH solution was obtained with a high current efficiency. Current efficiency was changed by the variation in the ani on of tetramethylammonium salts and sufficient result was obtained with hydrogencarbonate among sulfate, chloride, and formate salts (Fig.2). The decrease in current efficiency was more prominent with the stronger acid in the anolyte. It was suggested that the important factor affecting current efficiency was the pH of the anolyte. All contaminents of metallic ions were less than 10 ppb, and the concentration of carbon dioxide was less than 10 ppm.

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Yokohama 2nd Department, Kure Research Laboratory, Babcock-Hitachi K. K.1-2-10 Isogo, Isogo-ku, Yokohama-shi 235 Japan Hydrolysis of glycerol trioleate used as a standard sample of lipid and the extraction of its fatty acid were carried out under supercritical conditions of CO₂ in order to develop a conventional technique to recover fatty acids in algae. Glycerol trioleate was hydrolyzed successfully under the tempreture of 250°C and pressure of 8 MPa by adding water to the supercritical fluid of CO ₂. In the conditions glycerol and oleic acid was not extracted in the CO₂ fluid. After the hydrolysis the oleic acid was extracted in high efficiency at the CO₂ supercritical fluid density higher than 0.55 g/cm³ without accompanying glycerol extraction in which the temperature of 80°C and the pressure of 20 MPa was selected as one of the extraction conditions. No degradation of the fatty acid exposed to the hydrolysis and extraction conditions were observed by liquid chromatographic analysis. From above results, it was found that the process of hydrolysis of lipid followed the extraction of their fatty acids was easily performed by changing only tem perature and pressure in one vessel.

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Characteristics of clay materials for the separation of carbon dioxide from N₂-CO₂ mixture have been investigated by gas chromatography. The separation ability is evaluated by the difference in the reten tion times for carbon dioxide and nitrogen. Zeolite and sepiolite exhibit the separation ability up to 673k, while montmorillonite, saponite and silica gel show no separation ability above 573 K. The relatively higher separation ability of zeolite and sepiolite is attributed to the relatively higher heats of adsorption for carbon dioxide than those for nitrogen and their higher surface areas.

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The amount of ADP can be easily determined spectrophotmetrically as the amount of NADH oxidized by use of combined reactions of pyruvate kinase and lactate dehydrogenase. We investigated whether IDP and GDP could be also determined in the same coupled-enzyme system if they were incubated for a longer period with an increased amount of pyruvate kinase. It was shown that IDP and GDP could be utilized to produce the corresponding amount of NADH oxidized and that 0 to 300 nmols of these nucleo tides were able to be determined spectrophotometrically.

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