There are many kinds of microalgae who have adapted to extremely diversified marine environments. Screening of new useful materials from marine microalgae has been carried out. High density culture system using photo-bioreactor and genetic manipulation technology have been employed in order to enhance productivity of those materials from marine microalgae. We have found many useful materials, such as UV -A absorbing substance, plant growth regulating factor, polysaccharides, unsaturated fatty acids and antibiotics, from marine microalgae. Here, we describe production of those useful materials and their application. Marine coccolithophorid algae convert CO₂ to CaCO₃ and they have been expected to contribute to CO₂ recycling system. Metabolic engineering in marine microalgae, especially cyanobacteria, has been established. Eicosapentaenoic acid is successfully synthesized in marine cyanobacterium which can not synthesize it.

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Various kinds of crystalline aluminium orthophosphates have been prepared in the reaction of alumini um hydroxide with phosphoric acid under the various conditions of heating temperatures, reaction times, water contents, and sort of organic solvent. (1) Aluminium orthophosphate, AlPO₄ (berlinite, cristobalite-form, tridymite-form, and A-form), is formed by the dehydration of aluminium orthophosphate dihydrate, AlPO₄ 2 H₂O (metavariscite). The formation of these crystalline aluminium orthophosphates strongly depended on the sort of organic solvent, the water content and the amount of phosphoric acid. (2) Mixing of water and organic solvent shortened the r eaction time comparing with the conventional method to get metavariscite. Insoluble organic solvent having a boiling point around 100° C improved effectively the chemical reaction. The suitable condition for the preparation of metavariscite was as follows; H₃PO₄, Al(OH)₃, H₂O, and organic solvent were mixed with the molar ratio of 0.33: 0.30: 4.0: 1.5, and then they were heated with stirring under reflux for 15 h. (3) The optimum condition to prepare each species of AlPO₄ was as follows; For berlinite and -cristobalite-form the starting material with the same molar ratio as mentioned in (2) was treated in 1butanol and isobutyl methyl ketone, respectively. Berlinite and cristobalite-form were formed by the dehydration for 12 and 6 h after the refluxing for 12 and 20 h, respectively. Tridymite-form and A-form of AlPO₄ were obtained by the dehydration of metavariscite. The former was prepared by dehydrating with P₂O₅ (O'-form ) in 1-butanol for 48 h, the latter in 1-butanol for 6h. (4) Physicochemical properties (acidity and acid strength of the solid, s pecific surface area, average particle size, and adsorption of ammonia gas) showed that especially cristobalite-form and tridymite -form were superior on the surface activity to those formed by the conventional heat-treatment method.

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At mild conditions such as 80°C and atmospheric pressure, zeolites containing iron (III) ions in the framework were prepared from a homogeneous solution or somewhat heterogeneous mixture as a starting material. Si nce iron (III) ions can be incorporated into excess silicate ions forming a soluble complex, [FeSiO(OH)₃]²⁺, the iron (III) nitrate solution was first added to an excess of sodium metasilicate solution (Si/Fea≥50). Then various aluminium sources were added until Si/(Al+ Fe) and Fe/ (Al + Fe)become 20 and 0.00-0.40, respectively. When sodium aluminate was used as aluminium source, the solution became homogeneous (system 1), whereas aluminium nitrate lead to a partly heterogeneous mixture (system 2). The solid prod ucts obtained from both the systems were characterized by XRD, IR, SEM, ICP-AES and magnetic susceptibility methods. These analyses confirmed the formation of Linde B₁ and B₄ from the two systems and the presence of iron (III) in their zeolite lattice framwork. The extent of iron (III)substitution goes up to 40% in the products from system 1 and ca.25% in those from system 2. These values are fairly large as compared with those reported in the literatures. In conclusion, system 1 is a better starting material than system 2, because the former gives higher crystallinity and larger extent of iron substitution.

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The syntheses of rare earth orthoaluminates RAlO₃ were performed by arc melting method. Single phases of RAlO₃ were obtained for R = LaTm except Ce, however, only mixed phases of R₃Al₂O₁₂ and R₂O₃ were found in the case of R = Yb and Lu. CeAlO₃ was also obtained although a small amount of CeO₂ and Al₂O₃ precipitated at the grain boundaries. The structures of RAlO₃ for R = La, Pr and Nd belonged to trigonal system: CeAlO₃ was tetragonal, and those of RAlO₃ for SmTm were orthorhombic. By a solid reaction method for the syntheses of RAlO₃ for R=Ce, Pr and Tb, the reduction treatment of rare earth elements to +3 was indispensable, while, these phases were successfully synthesized by arc melting method without any special reduction process, applying its “ thermal effect on the reduction” at high temperature processing. Tetragonal phases of CeAlO₃ was directly obtained from melt for the first time in this investigation, and CeAlO₃ decomposed into CeO₂ and Al₂O₃ in air by heating up to 1380° C. On the other hand, PrAlO₃ and TbAlO₃ were stable against the above heat treatment.

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Polycrystalline specimens of HoRh₃B_1-x, which consists of high reactive (Ho) and melting (Rh, B)elements, have been successfully synthesized by arc melting method. Extreme evaporation of the constituent elements has not been observed. Compound of HoRh₃B_1-x, has perovskite type cubic structure (space group: Pm3m). The concentration of boron is distributed between x=0 (20 atom%B) and 0.506(11 atom%B) for HoRh₃B_1-x. Lattice parameter of a in HoRh₃B_1-x, depends on x, and varies lineary from a =41.51(1) nm (x= 0) to 40.71 (1) nm (x= 0.506). This compound shows paramagnetic behavior following the Curie-Weiss law between 4.2 and 300 K. Almost the same effective magnetic moments of 10.44 and 10.40 μ _B in x=0 (20 atom%B) and 0.294 (15 atom%B), respectively, are in good agreement with the theoretical Hund value of 10.60 μ _B for Ho⁺³.

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Spherical monodispersed ZnS particles were prepared from Zn ( NO₃)₂ aqueous solution by homogeneous precipitation method using thioacetamide at 60-90°C and the effect of reaction conditions for the morphology of ZnS particles was investigated. The morphology of ZnS particles (zincblende structure)changed from monodispersed to polydispersed or aggregated particles with reaction time. Spherical monodispersed ZnS particles with diameter of 0.2-0.8 μ m were obtained at 60-80°C under intermediate values of the initial concentration products, [TAA]₀[Zn²⁺]₀, and short reaction time. The critical supersaturation ratio was 4 x 10²(60°C) 1 x 10³(80°C) and the nucleation rate increased with increase in the initial concentration product, [TAA]₀[Zn²⁺]₀.

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The reactions of trans-2-benzoyl-3-phenylaziridines (1) with tosylhydrazine (2-1) and semicarbazide (2-2) were studied in detail. When the reaction of 1 with 2-1 was conducted in acetonitrile in the presence of polyphosphoric acid (PPA) as an acid catalyst using a mechanical stirring system, 1-tosy1-2-pyrazoline derivatives (3) were obtained in excellent yields. The treatment of 1 with 2-2 in mixed solvent (EtOH/H₂O) gave 1-carbamoyl-2-pyrazoline derivatives (4) having the similar skeleton in moderate yields. Both 3 and 4 have a trans-configuration at 4, 5-positions in the pyrazoline ring. In the case of 1 having a para methoxy substituent on the benzoyl group, the yields were low.

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Cross aldol reaction of isophorone (1) with several substituted benzaldehydes was attempted. Some mild reaction conditions gave a hydroxylated addition compound (9) as the intermediate. Some of the dehydrated products showed the growth inhibitory effect against L-1210. Furthermore, 3-oxygenated isophorone derivative (10) was obtained by the oxidation of 1 with Fieser's reagent.

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Sap of the lacquer tree dries into a brilliant and tough film. It is a latex composed of urushiol, water, plant gum, water-insoluble glycoprotein, and laccase. Thermal degradation of the lacquer film was studied by pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS) using two and single-stage pyrolysis techniques. Urushiol, plant gum and waterinsoluble glycoprotein which were isolated from the lacquer sap was used to study the pyrolytic behavior of lacquer film by single-stage pyrolysis under best optimum pyrolysis condition. The characteristic peak appearing on the pyrograms were identified using a mass spectrometer which was directly attached to the gas chromatography. On the basis of the observed pyrograms, the degradation and polymerization mechanisms of the lacquer film were discussed. Consequently, it was evidenced that the format ion of lacquer film proceeds through the side chain-side chain C-C coupling and nucleus-side chain C-O coupling besides phenol coupling and nucleus-side chain C-C coupling.

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Metal phthalocyanine derivatives exhibit high redox abilities. A new type of metal phthalocyanine derivative, metal anthraquinonecyanine have been synthesized. Metal anthraquinonecyanine which has four 9, 10-anthraquinone units is expected to possess a higher redox property. Cyclic voltammograms were measured in the metal anthraquinonecyanine in order to examine its redox property. Cyclic voltammograms of metal anthraquinonecyanines exhibited a redox property. The metal anthraquinonecyanines had no appearance of an effect on the redox property of 9, 10-anthraquinone. The redox properties of metal phthalocyanine derivatives were influenced by the ring current of ir electrons about the conjugated path. As metal anthraquinonecyanine is also a conjugated planer molecule, π electrons of 9, 10-anthraquinone units in the metal anthraquinonecyanine are incorporated into the macrocycle conjugated path of porphyrazine ring.

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The operational change in platinum particles sizes of the electrocatalysts in a PAFC (Phosphoric Acid, Fuel Cell) was evaluated using the method of Kerkhof. The particle size determined by X-ray photoelectron spectroscopy (XPS) almost agreed with that by X-ray diffraction (XRD). The small difference between the results of two methods might be attributable to the broad distribution in the platinum particle size and/or the difference of the surface sensitivity of XPS and XRD. Furthermore, the morphologies of the platinum particle at the surface and in the inside of the electrode after cell operation were observed using fieldemission scanning electron microscope (FE-SEM). The particle size at the surface was larger than that in the inside of the electrode. In particular, the clustered particles were only observed at the surface. Such clustered platinum particles at the surfaces showed the effect of the electrolyte attack or "surface corrosion" and were considered to be formed through the coalescence mechanism. On the other hand, the number of platinum particles was scarce in the inside of electrode (cathode), which indicated the dissolution of platinum from the cathode. Thus, the present study supports the idea that the particle growth is proceeded by the dissolution-redeposition process and/or coalescence process.

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A potentiometry which does not require the adjustment of the ionic strength of a sample, combined a standard addition with additions of a diluent and the sample solution, is proposed. After the sample, of v olume V, is titrated with the diluent, the sample so lution of a certain volume V₀is a dded. Subsequently it is titrated with the standard solution containing the analyte ion of a k nown concentration (c_s) having the same ionic strength as that of the diluent. If t he electromotive forces, E₁ and E₂, which correspond to the titration volumes, v_d and v_s, by the diluent and the standard solution that satisfy a condition of υ _s=υ _d[1+(V₀/V)]υ _d0 are read off respectively on the two titration curves, the concentration, c_x, of the analyte ion is determined from the slope of a linear plot of (10^{δ E/S}1) vs. (υ _dυ _d0') going through the origin (υ _d0 is the final volume of the diluent added): 10^{δ E/S}1 = [c_s/ (c_x V)]· (υ _d υ _d0')where υ _d0'= υ _d0/[ 1 + ( V₀/ V )], Δ E=E₂E₁, S is a response slope of an ion-selective electrode. The present method has the following a dvantages in c omparison with the previous m ethod; the standard solution of the known concentration is only one and the calculation of variables for plots is simple. The present method could be applied to the fluoride and copper (II) determinations with the better precisions than those obtainable with the previous method.

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A serial dissolution and precipitation of silica in aqueous catechol-KOH solutions was studied by colorimetric analysis, solubility measurement of silica under hydrothermal conditions and potentiometric titration. They confirmed the formation of catecholsilicate. The plant-opal formation and the metabolism in plant were discussed. It revealed that silica firstly dissolves and transport as catecholsilicate in alkaline reductive conditions and they precipitate from the catecholsilicate compounds in the acidic oxidative conditions. The results suggested that the silicate migration in plant may proceed from these dissolution-precipitation process with redox reaction of lignin.

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The kinetics of chemical hydrolysis of simazine (2-chloro-2, 6-bis (ethylamino) -1, 3, 5-triazine) was investigated under alkaline conditions. The rate constants (k) and half-lives (t_1/2)w ere determined, and then activation energy (E_a) of hydrolysis of simazine was calculated. Simazine was easily hydrolyzed in NaOH solution. The hy drolytic rate increased with raising the reac fion temperature and increasing the amount of NaOH. The rate constants (k) at 60, 70°C and 80°C were 0.0684(s^-1), 0.127 (s^-1) and 0.236 (s^-1), respectively. The half-lives ( t_1/2) at 60, 70°C and 80°C were 10.13 (h), 5.46 (h) and 2.94 (h), respectively. The activation energy (E_a) of hydrolysis was 6.04 x 104(J mol^-1), this value agreed with the one calculated by Burkhard et al. Simazine would be hydrolyzed by the mechanism as fllows; chloro subst ituents linked to triazine ring are reacted with by hydroxide ions to form hydroxy substituents. The liberated chloride ions are reacted with water, so that hydrochloric acid is formed. The resulted hydrochloric acids are neutralized by NaOH.

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