Thermal properties of the products formed by the hydrolysis of α-tricalcium bis (phosphate) (α-TCP) in solubilized collagen solutions were compared with those of hydrolyzed products without collagen, solubilized coll: ens, a commercially available hydroxyapatite (HAp) and a bovine tooth. The water of crystallization in c alcium hydrogenphosphate dihydrate formed at pH 4 wa s dehydrated in t wo steps (at ca.150 "C a nd ca.2 00°C). T here was no d ifference in t he total weight losses ( TG) of the hydrolyzed products through dehydration, but the ratio of the weight loss at ca.150°C t o that at ca.2 00°C w as different by the presence of collagen. The two peak temperatures (DTA) due to dehydrati on were varied owing to collagen.
The weight loss in T G (the amount of absorbed water and that of water due to the condensation of octacalcium dihydrogenhexakis (phosphate) (OCP) ) was maximum when the hydrolyzed product was obtained in solution of pH 5, though there was no weight loss in a commercially available HAp to 800 °C. The collagen content was maximum when the hydrolyzed product was obtained in s olution of pH 5. Th e correlation between the collagen content and the weight loss in TG was found. The peak temperatu re due to thermal decomposition of collagen in the hydrolyzed product was ca.3 50°C, a s well as collagen in, a b ovine tooth. However, the peak temperature was lower by c a.170°C t han that of the solubilized colla gen (ca.520 °C).
Therefore, the hydrolyzed product obtained in solution of pH 5 contained OCP and collagen in a ddition to HAp, and the collagen was thought to disperse uniformly in the hydrolyzed product as fine fibril.

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Nickel porphyrins and oxovanadium porphyrins in oilsandstone produced in Bolivia of South America were analyzed by three-dimensional reversed phase high-performance liquid chromatography (3DHPLC)and accurate mass determination with El-MS. Twenty-one species of nickel porphyrin and twelve species of oxovanadium porphyrin were present in oilsandstone, respectively (Figs.5 and 6). The demetalation products of nickel porphyrins were also analyzed by 3D-HPLC (Fig.8). They had four absorption maximums for Q-band in the wavelength region 490 to 620 nm. The order of absorbance of the maximums for Q-band gave the presence of two types of porphyrins, namely deoxophylloerythroetioporphyrin (DPEP) type and etioporphyrin type, distinguished by containing pentane ring.
From result of 3D-HPLC and accurate mass determination, twenty-four species of nickel porphy rins and eighteen species of oxovanadium porphyrins have been found to present, resepectively. The number of DPEP type species of nickel porphyrins was less than that of etioporphyrin type species of them. On the other hand, both types of oxovanadium porphyrins were almost equal in number of their species (Table 1). Therefore, thermal transformation of DPEP type into etioporphyrin type in production process of fossil fuels was suggested.

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A preconcentration procedure using poly (vinyl methyl ether) (PVME) is proposed for determining a trace amount of phosphate in water samples. PVME, a thermally reversible polymer, is soluble in water below 31°C, and shrinks abruptly by heating above 31°C becoming insoluble. With phase separation of PVME from aqueous solution, certain hydrophobic substances were incorporated into PVME. Hydrophobic aggregate of Molybdophosphate-Malachite Green (denoted P-Mo-MG) was formed by the reaction of phosphate and Mo-MG reagent (mixture of ammonium molybdate and MG). The solution of PVME was added to the P-Mo-MG aggregate and was warmed to 45°C followed by shaking. The PVME gel shrank, so that the P-Mo-MG aggregate along with PVME stuck to the walls of the test tube. Supernatant solution was discarded by decantation and the P-Mo-MG aggregate was dissolved in a small volume of Methyl Cellosolve along with PVME. The absorbance (λ_max= 627 nm) was proportional to the concentration of phosphate. Apparent molar absorptivity of P-Mo-MG solution with PVME was 2.6×10⁵ dm³ mol^-1 cm^-1. The method makes it possible to determine phosphate in amount ranging from 0.5-20 nmol/test. The coefficient of variation was 3.5% in the determination of 5.0 × 10^-7mol dm^-3 phosphate. The method was successfully applied to the determination of phosphate in water samples such as tap water, mineral water and river water.

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The photograftings of hydrophilic monomers such as methacrylic acid (MAA) and 2- (dimethylamino)ethyl methacrylate (DMA) onto flat, porous, and expanded poly (tetrafluoroethylene) (f, p, and ePTFE)films, which had been treated with oxygen plasmas at 50 or 200 W beforehand, were carried out by applying UV rays emitted from a 400 W high-pressure mercury lamp in t heir aqueous monomer so lutions. The wettabilities and surface composition of the grafted PTFE films were examined as a function of the plasma output and the grafted amount. We thus established a new technique to g raft the hydrophilic monomers onto PTFE films by combining the plasma treatment and photografting. Vario us oxygen-containing functional groups including hydroperoxide groups, formed by the plasma trea tment, effectively acted as active sites for photografting. The grafted amounts increased with increa sing plasma output. For the photograftings onto pPTFE and ePTFE films, the grafted amounts more considerably increased at shorter UV-irradiation times. The photograftings onto fPTFE film are definitely limited to the surface region, and for pPTFE and ePTFE films grafted polymer chains progressed into the interior of the films along the surfaces of the pores. The contact-angle measurement and the surface analysis by ESCA reveal that the wettabilities on the grafted fPTFE surfaces became constant irrespective of monomer concentration when the fPTFE surfaces were covered with grafted polymer chains. In add ition, as the grafted amounts at which the wettabilities became constant decreased with increasing plasma output due to the formation of more oxygen-containing functional groups in the vicinity of the surface region.

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Four macrocyclic polyamides, 6.20-diocty1-3, 6, 9, 17, 20, 23, 29, 30-octaazatricyclo[23.3.1.111, 15]triaconta1 (29), 11, 13, 15 (30), 25, 27-hexaene-2, 10, 16, 24-tetrone (L¹), 4-octy1-1, 4, 7-triazacyclotridecane8, 13-dione (L²), 4-octy1-10- (2-pyridylmethyl) -1, 4, 7, 10-tetraazacyclododecane-2, 6-dione (L³)and 4- (2-pyridylmethyl) -1, 4, 7-triazacyclotridecane-8, 13-dione (L⁴) have been synthesized and the composition of the complex and the extraction equilibrium constants log Kex have been determined by solvent extraction for some transition metal ions (Cu²⁺, Co²⁺, Ni²⁺, Zn²⁺ ).
These ligands formed the cationic complexes as 1: 2 ( Ll: Cu²⁺) and 1: 1 ( L² and L³; Cu²⁺), and extracted Cu²⁺ selectively from an equeous solution in the presence of picrate ion into 1, 2-dichloroethane. Values log Kex for the cationic complexes of Cu²⁺ with each ligand were increased in the order L¹ < L² < L³.
In paticular, L³ possessing a pyridine ring appendage of cooperative binding extracted Cu²⁺ effectively even in a strong acidic equeous solution, and extracted Co²⁺, Ni²⁺, Zn²⁺ with same extent to Cu²⁺from a singl metal solution, however predominantly extracted only Cu²⁺ in the competitive extraction of these ions and Cu²⁺. L¹ and L² have little binding ability for Co²⁺, Ni²⁺ and Zn²⁺ ions. L⁴ was soluble to some extent in the equeous phase, thus it is not appropriate as a ligand of solvent extraction.

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In order to develop chelating resins having high adsorption and elution abilities toward noble metal ions, resins containing epithio groups (RGS) were prepared by the reaction of macroreticular glycidyl methacrylate-divinylbenzene copolymer beads (RG) with saturated methanol solution of ammonium thiocyanate. Alternative resins having mercapto groups (RGSH) were also derived from RGS by treatment with ethanolic potassium hydrogensulfide. From a series of RGs prepared by systematically changing amounts of the diluent 4-methyl-2-pentanone, and the crosslinking agent, divinylbenzene, in suspension polymerization, RGSs and RGSHs with different specific surface areas and degrees of crosslinking were derived, and their behavior in adsorption and desorption of Au(III), Pd(II) and Pt (IV) was studied. The RGS10-160 and RGSH10-160, which were derived from the RG prepared by using 10 mol%of divinylbenzene and 160 vol% of the diluent, exhibited the highest capacities for uptake of each metal ion, respectively. Bachwise elution study has clarified that the metal ions adsorbed on RGS10-160 or RGSH10-160 are effectively eluted with 0.1- 0.2 mol dm^-3 aqueous potassium cyanide; in particular, the elution of Au (III) and Pd In adsorbed on RGS10-160 is easy. The column-mode study on RGS10-160 has also revealed that each metal ion can be quantitatively eluted with 0.2 mol d m^-3 pota ssium cyanide. Although the separation of Au (III) and Pd(IV) with cyanide eluents was difficult, the quantitative separation of Au (III) and Pt (IV) was successfully achieved by changing the concentration of cyanide eluents.

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First, the mixtures of colloidal silica dispersion and aqueous solutions of silane-containing PVA were investigated in terms of gellation. The gellation was apt to take place with an increase in silane content, and in degree of polymerization of silane-containing PVA, and with the decrease in particle size of colloidal silica. The gellation was observed to be more favorable in neutral pH range and in the equal amounts of the both components. The gellaion was estimated to occur between the silanol groups in the surfaces of colloidal silica particles and the silanol groups in PVA, followed by mutual reaction or agglomeration of the the reacted particles. Second, the properties of the films obtained from casting the aqueous mixtures were investigated. The films composed of silica and silane-containing PVA were transparent, while those composed of silica and conventional PVA were opaque. These phenomena show the agglomeration of silica particles during the film formation in the case of conventional PVA, where there does not exist the strong interaction between both materials differing from the former case. The experiments of degree of swelling of the films in water reveal the cross linking of silane-containing PVA caused by silica. The structure of the crosslinked portion seemed to be C-O-Si. Mechanical properties of the composite films showed almost no lowering at 80°C, whereas those of conventional PVA films as well as those of silane-containing PVA films lowered significantly. The phenomenon was attributed to the increase of glass transition temperature of silane-containing PVA induced with crosslinking.

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The contribution of hydrogen bonding between the anthraquinone dyes and protic or aprotic solvents was spectroscopically investigated using the modified McRae's equation. The contribution of th e hydrogen bonding between the dyes and methyl benzoate or poly (ethylene terephthalate) film (PET) was evaluated on basis of the results.1-Amino-, 2-amino- and 2- (methylamino) anthraquinones act as a proton donor. The bond energy for the hydrogen bonding between 1-propanol and the dyes was estima ted to be 3∼6 kcal/mol, corresponding to 20∼60% of the total interactions. The bond energy for the hydro gen bonding between the dyes and methyl benzoate or PET was estimated as 1∼4 kcal/mol, corresponding to 10∼40% of the total interactions. The degree of contribution to hydrogen bonding in the interactions between anthraquinones (anthraquinone, 1-methylamino-, 1-dimethylamino-, 1-hydroxy -, 1-methoxy- and 2- (dimethylamino) anthraquinone) and methyl benzoate or PET was found to be quite low.

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Polyacrylonitrile (PAN) -based carbon fibers are produced by oxidizing precursor PAN fibers and then carbonizing the obtained oxidized fibers. The oxidation conditions of the precursor PAN fibers govern not only the performance but also the productivity of PAN-based carbon fibers. The effects of the composition of the precursor PAN fibers, in which methyl acrylate (MA) was incorporated by copolymerization, on the productivity of carbon fibers were investigated. Shrinkage, the amount of chemically-bound oxygen and formation of skin-core structure in the fibers oxidized at a temperature varying 220°C to 280°C, and also shrinkage, carbon yield and tensile strength of the carbonized fibers were measured. These properties were investigated as functions of the MA content in PAN and of the oxidation time. In order to get the carbon fibers with high strength with high productivity, in other words, in short oxidation time, it was found that the precursor PAN fibers containing 4∼6 wt%MA had to be oxidized up to the chemically-bound oxygen content of about 12% at a maximum temperature at which a skin-core structure in the fiber was not formed.

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A method was described to collect the cadmium ion in water with the boiling water-treated powder algae of Dunaliella salina (BWP). The algae powder was treated with the boiling water. A 10 ml solution containing Cd²⁺ was mixed with 10 mg of the BWP under stirring for 30 min. The solution was then centrifuged or filtered through a glass fiber filter (0.2 μm) and the concentrations of cadmium ion in the filtrate were determined with an atomic absorption spectrometer. The amount of cadmium absorbed in the BWP became a maximum at 15 min after exposure. In a mixed solution of Cu²⁺, Mn²⁺, Co²⁺, Zn²⁺, Fe²⁺, and Ni²⁺, the collect of the metals by the BWP was Cu > Fe > Cd > Zn, Co > Mn. The cadmium collected by the BWP increased with an increase in the concentration of nitrogen in the growth medium. The amount of cadmium absorbed in the BWP increased with an increase of the amount of algae in water. The amounts of Cd absorbed by the BWP treated with a alkali (ABWP) was increased and the amounts of Co, Cu absorbed in ABWP were decreased.

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Temperature dependence of cathode open circuit potential (OCP) at various O₂ concentrations was examined using a floating electrode half cell apparatus. The OCP was found to be lower than expected from the Nernst equation when the catalyst layer was less wetted by the electrolyte solution. For the wetted catalyst layer, the OCP decreased with rising temperature, except below 100°C. This was probably due to the decrease of wettability of the catalyst layer and the prevention of the gas diffusion to the catalyst layer surface by the thick electrolyte film formed on it.

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The partial specific volume and the partial specific adiabatic compressibility of a-chymotrypsin in phosphate buffer solution and in sodium chloride solution were measured at 25°C. The values of these properties increased with increasing the ionic strength. Concentration dependence curve in buffer solution shows maximum, while it shows minimum in NaC1 solution. The extrapolated values to ionic strength zero of these properties were different for both solution. These results reflect the different type of interactions between α-chymotrypsin and anions.

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Ni-Al-O mixed oxide prepared by coprecipitation has been found to be active for the selective reduction of NO by hydrocarbon in the wide temperature range, 400-550°C. The maximum catalytic activity was observed at 0.15-0.35 of Ni/Al mole ratio. The catalytic activity decreased with increasing the calcination temperature above 800°C due to the decrement of specific surface area. XRD measurement revealed the presence of spinel-type NiAl₂O₄.

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Liquid-phase hydrogenation of crotonaldehyde has been examined over supported metal and bimetallic catalysts. Formation of crotyl alcohol was observed over alumina-supported Pt and Co catalysts. Coand Pt-based bimetallic catalysts were also examined. Bimetallic catalysts were prepared by selective deposition method, using volatile complexes as the precursors of second metallic components. Promotion effects of second metallic components were found especially on catalysts containing Zr, Ti and Ru. By addition of Zr (dpm)₄ on Co-Al₂O₃, formation rate of crotyl alcohol increased significantly with the decrease in by-products.

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Changes in surface structure of polyimide films by the buffing process are investigated. In general, liquid crystal materials can be homogeneously aligned by buffed thin films of appropriate polymer, such as polyimide, but the mechanism is not clear. In this study, X-ray photoelectron spectroscopy (XPS) analysis based on a molecular orbital calculation has been succcesfully applied to determine the chemical bonding state of the polyimide surface. On the basis of the XPS analysis, it is found that the imide ring moiety is selectively modified by the buffing process.

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From Rabdosia umbrosa var. excisinflexa( N AKAI) HARA were isolated two diterpenoids, five fiavonoids, one aromatic compound, and two steroids. They were identified as kameban in, kamebakaurin, pedalitin, 4'-O-methylpedalitin, genkwanin, pilloin, eupatorin, methyl caffeate, β-sitosterol, and β-sitosterol glucoside by the comparison of spectroscopic data with those of the authentic samples. It was clarified that both β-sitosterol and aglycon of β-sitosterol glucoside contained stigmasterol and campesterol by GC-MS.

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