Effects of carboxymethylchitin (CM-chitin) and sulfated carboxymethylchitin (SCM-chitin) on the mitogenic activity of acidic- and basic-fibroblast growth factors (FGF-1, FGF-2) were investigated. CM-chitin showed proliferative activity without FGF, while the activation of FGFs' mitogenic activity by CM-chitin was not observed. On the other hand, SCM-chitin activated the mitogenic activity of FGFs and the activity was stimulated with a smaller dose of SCM-chitin when the degree of sulfatation was high. It was estimated that SCM-chitins did not show the cytotoxicity probably because of the carboxymethyl groups. In addition, carboxylated polysaccharide with a low degree of sulfation activated FGF, indicating that carboxyl groups contributed to the interaction between the polysaccharide and FGFs.

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The viscosities and the densities of the aqueous solutions of alkanols and sodium monocarboxylates with straight and branched carbon chain (with 1-4 carbon atoms) were measured at 25°C. The viscosity B-coefficients of Jones-Dole's equation and the limiting partial molar volumes, V∞, were determined. The molar volumes, V_B, was calculated from Eq.4. V_B is the value that represents volume of solutes with interacting water.
The change in V∞ with -H→-CH₃ substitution were not considerable in the case of the straight chain or in the case of the branched chain (Scheme 2). However, the change in V_B with -H→-CH₃ substitution in the case of the the branched chain was much larger than that in the case of the straight chain (Scheme 1).
Therefore the h ydration structure, which was suggested by the change in V→-V∞3 with -H→-CH₃ substitution in the case of the branched chain was formed stronger than that in the case of the straight chain (Scheme 3 and Scheme 4). This fact was supported by the values of hydration entropy (Scheme 5).
These hydrophobic hydration structure-making properties were considered to have caused the differences in the solubilities among butyl alcohol isomers in water.

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Electrochemical impedance method was applied to pasted-type negative electrodes (current collector: metal core sheet) of Ni-MH batteries. The following information was obtained during a charge-discharge cycle test without disassembling the batteries; 1) solution resistance, 2) contact resistance between particles of the active material, 3) impedance of the corrosion product, 4) charge transfer resistance and capacitance of the electric double layer at the interface between the electrolyte and the active material, 5) Warburg impedance caused by hydrogen diffusion in the active material.
It was also clarified that the porosity of the electrode was very important to analy ze impedance spectra measured by the pasted-type electrodes.

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The state of dissolved water in esters such as butyl acetate (BAc), t-butyl acetate (TBAc), ethyl hexanoate (EH), hexyl acetate (HAc), 2-hexenyl acetate (2HEAc), methyl decanoate (MD), methyl 10-undecenoate (MU), methyl linoleate (ML) and dioctyl phthalate (DOP) were studied by FT-IR spectroscopy and examination was also made of thermal stability of these water clusters in such esters.
The water clusters formed by interaction between the ester and water molecule, and consiste d of the small ctusters (C1, C2 and C3) and the large clusters (LC1, LC2 and LC3). The Cl (dimer and trimer)were formed in the free volume among hydrophobic groups (alkyl and allyl group). The C2 due to the hydrogen bond by interaction between the carbonyl group and water molecule, and the C3 were formed by interaction between the ether group and water molecule.
In TBAc, the magnitude of the size of Cl, as comp ared with clusters in BAc, was miniaturized but the amount of C2, LC1 and LC2 were increased.
The amount of dissolved water i n esters decreased in the following order.2HEAc>H Ac>EH. In 2HEAc, the amount and the magnitude of the size of clusters increased by the interaction of the doub le bond of acyl group and water molecule.
In MU, ML and DOP, the cl usters were changed under the influence of the carbon number of alkyl group, allyl group and double bond. The amount and themagnitude of the size of clusters incresed by the interaction of water molecule and double bond (allyl group).
In the range from 40 to 80°C, the Cl disappeared by vaporiza tion of the water molecules. The LC2 and the LC3 in the dissolved water were gradually ruptured into smaller cluster with increasing temperature, but a little remaindat 180°C. The water molecules produced by thermal decomposition of large clusters recombined with anhydrous ester in the process of diffusion and vaporization in the ester.

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To further increase the Mo adsorbing capacity of Mo adsorbent (hereinafter abbreviated as PZC)which are synthesized by using zirconium tetrachloride (ZrCl₄) and isopropyl alcohol, the chlorine atom concentration was increased in the PZC. As a result, the Mo adsorbing capacity of the PZC was found to increase from the conventional 200 mg to 250 mg/g-PZC. Since the PZC adsorption capacity depends on the ratio of adjacent chlorine atoms in the PZC molecules, the mechanism with which the PZC adsorbs the Mo is thought to be one of chemical adsorption backed by chemical reaction between the two adjacent Zr-Cl bonds and MoO₄^2-. Since the PZC having high Mo adsorption shows more adsorption than an estimated value, the effect of Mo polyions cannot be ignored.
The ^99mTce lution yield of the Generator was measured using the PZC which adsorb Mo including 1 to 470 MBq ⁹⁹Mo. The PZC was filled within a glass column with glass filter. The elution yield was found to be stable in the values ranging from 75-90% in each case. No increases in break-through of ⁹⁹Mo were observed even by adsorbing ⁹⁹Mo at 470 MBq, thereby it suggests that the PZC is kept stable, not being decomposed even under the condition of high radioactivity. t Synthesis of Inorganic Polymers as Ion Exchanger. Part 2.

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Examination was made on the supercritical carbon dioxide extraction of agricultural chemicals from aqueous solutions. In the case of the semi batch extraction blowing supercritical carbon dioxide into the aqueous solutions at a concentration of 5 mg L^-1, the dependencies of the removal ratios of four kinds of agricultural chemicals on temperature and pressure were shown in different patterns depending on the agricultural chemicals. For simazin (CAT), no unusual phenomena were observed. On the other hand, isoprothiolane (IPT) exhibited unusual phenomena. That is, the removal ratios decreased, as the pressure increased above 100 kg cm^-2 at temperatures of 45°C and 50 C. A similar phenomenon was observed for fenitrothion (MEP) or napropamide (NPP). Complicate pattern was shown for MEP. The removal ratios at pressures of 80 kg cm^-2 and 90 kg cm^-2 had maxima at 40°C and 45°C, respectively. These phenomena were discussed in terms of equilibrium and mass transfer. It was referred to that consideration should be given to such phenomena when the extraction technique is used for analysis. The order of the easiness of the separation of agricultural chemical from aqueous solution (that was estimated by the removal ratio at temperature of 35°C and pressure of 100 kg cm^-2) was IPT>NPP>MEP>CAT. Correlation was seen between the removal ratio and the solubility of agricultural chemical in water, and in hexane or the melting point.

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A representation method for substructures associated with H-NMR spectra has been developed. The method, HYPER code system, is based on concentric layers of nearest neighbors around a central atom. We also developed a program, “HYPERGEN”, which creates HYPER codes for substructures from the structural information of a compound. Since substructure-subspectrum correlation information is requisite for data oriented structure elucidation systems, HYPER code plays a significant role in analyzing H-NMR spectra.
For creating a corr elation table it is required that not only the structures and spectra are input, but also information on their assignment. We have therefore also developed a representation method for the assignment. An NMfile format has been defined for this purpose. It consists of structural information, chemical shifts with the corresponding atom numbers, and auxiliary information.
The HYPERGEN system accepts input data in the NMfile format and from this creates HYPER codes. The HYPER codes provide information on the number of hydrogen atoms attached to each carbon. Such information is also provided for the last sphere of a substructure, even though there is no information about nodes and bonds connected to it. The codes for the geminal protons, which are connected to the same carbon atom but have different chemical shifts, are also produced in order to distinguish the difference between chemical shifts.
Although the HYPER codes are theoretically able to represent an infinite number of spheres as substructures, for the purpose of this study we have employed up to the sixth sphere. Larger substructures can be represented through a combination of them in a structure generation process of the structure elucidation system.
Using the HYPER codes we have constructed a correlation table between H-NMR subspectra and the corresponding substructures. This table will provide an indispensable constituent for structure elucidation systems.

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The effect of Ca content in Zn_1-x, Ca_xO(x=0-0.20) powders on its bactericidal action against Staphylococcus aureus was investigated. The bactericidal action increased with an increase of Ca content in Zn_1-x, Ca_xO, indicating the possibility of control of the antimicrobial efficacy. The death of S. aureus by the powder slurries followed first-order kinetics, and the concentration of Ca dopant slightly enhanced the dilution coefficient of the bactericidal action. Though the pH value of as-prepared powder slurries also increased with the increase of Ca content, its bactericidal action was greater than NaOH solution with the same pH value as the slurries.

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Organic-inorganic hybrid gels were obtained efficiently by one-pot procedure from tributylstannyl ester of polymeric silicic acid (PTBS), chloro (3-methacryloyloxypropyl) dimethylsilane (1a), and cornmon monomers such as styrene, acrylonitrile, and methyl methacrylate. In the reaction system, substitution of tributylstannyl groups of PTBS by silyl groups of la and copolymerization of methacryloyloxy group of la with a monomer proceeded simultaneously under UV irradiation at room temperature. The resulting gel should be consisted of covalently bonded three components and regarded as a nanocomposite material. The use of another chlorosilane lb, which had cyanopropyl group, with la led to formation of a multifunctional hybrid gel.

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Photocatalytic tiles (2, 3, 4, 5) containing titanium dioxide were prepared under various conditions, and what effect can be obtained by them for the removal of algae was investigated. Photocatalytic tiles 4, 5 were prepared by applying to the standard tile 1 a coating agent comprising titanium dioxide and copper ( II ) acetate and calcining the coated tiles at 350°C and 600°C. Photocatalytic tile 2 exhibited a higher effect in removing stigeoclonium and gomphonemea. Especially tile 5 prepared at low temperature indicated the highest removing effect. The algae removing effect of the photocatalytic tiles decreased with an increase in water depth.

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We already found and reported that the specific polymorphs of, μ-oxo-aluminum phthalocyanine dimer and μ-oxo-gallium phthalocyanine dimer have fairly good characteristics as the electrophotographic receptor. In connection with our ongoing works on this field, we are interested in the synthesis of μ-oxo-bridged dimers of diverse metal phthalocyanines for persuing various charge generating materials in electrophotographic receptors. We report here the results of studies on the polymorphs of the titled phthalocyanine dimer, i. e. μ-oxo-bridged between aluminum and gallium phthalocyanine dimer, and their primary electrophotographic evaluation.

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