We have proposed a reaction mechanism to form fine metallic particles in the interlayer spacing of graphite. Graphite intercalation compounds (GICs) with metal chlorides were immersed in lithiumnaphthaleneorganic solvent mixture. Metal chlorides were reduced in the interlayer spacing of graphite, and fine particles of corresponding metal were obtained. The size of metallic particles was estimated from the line width of X-ray diffraction profiles and transmission electron microscope (TEM)images. The particle size is found to depend on the activity of particle precursors (i.e. metal atoms or their aggregates) to move in the graphite gallery, which is determined by the bulk melting point of the metal and the reaction temperature. If the bulk melting point is low and the reaction temperature is high, the precursors move more actively and grow to a great size. Assuming this mechanism, the dependence of the stage number of starting GICs on the particle size is also explicable; the size increases with decreasing stage number. The particle size is also affected by the solvent used for the reduction. When the solvent molecules are co-intercalated together with lithium into the interlayer spacing of the GIC, they facilitate the reduction of metal chloride, and relatively large metallic particles are obtained. Analyzing closely the TEM images, we predict that the metallic particles generated in graphite matrix has a form of a short cylinder, which is acceptable as the growth of particle is taken place in the twodimensional gallery of graphite interlayer. Fine metallic particles with controlled size supported in graphite matrix are expected to be useful for catalytic applications.

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The solid-state ²⁷Al MAS NMR is taken to be the best technique to quantify the amount of framework aluminums of zeolite. However, it is very difficult to evaluate accurately the amount of framework metals of metalosilicate because the solid-state MAS NMR is not necessarily effective for all metals in the metalosilicates. It is desirable to develop a new method for quantification of the framework metals. In this paper, we investigated an evaluation of the amount of framework iron (III) ions of ZSM-5 type ferrisilicate by water vapor adsorption. Adsorption isotherms of water vapor were measured on the Hferrisilicates with various SiO₂/Fe₂O₃ ratios. From the analysis of the adsorption isotherms by the D-R method it was found that the micropore volume W₀(H₂O) accessible to water molecules increases linearly with an increase in the framework iron (III) ions and that the number of water molecules associated with one framework iron (III) ion is on average 5.5. This indicates that water molecules are able to be used to determine the amount of framework iron (III) ions in the H-ferrisilicate structure.
Next, based on the above result, the amounts of framework iron (III) ions in H -ferrisilicates treated in air at 873∼1073 K was estimated. It was found that the rate of the removal of iron (III) ions from the ferrisilicateframework bythermal treatment is apparently second order depending on the amount of framework iron (III) ions in the H-ferrisilicate structure.

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The modification effects of lithium and manganese on the crystal properties of magnesium-based oxides were examined by the derivative thermogravimetry/differential thermal analysis (DTG/DTA)and the X-ray diffraction (XRD) technique. The Mn-containing MgO samples of various compositions were categorized two groups in terms of the predominant DTA endothermic peak accompanying the weight loss; 5 25 molY3-Mn/Mg0 (low-Mn) at 606 610 K and 50 and 80 mol%, Mn/Mg0 (highMn) at 648- 655 K, respectively. These peaks were not ascribed to the decompositions of the starting materials; manganese (II) acetate (628 K) nor magnesium hydroxide (697 K). The difference of the decomposition processes under heating reflected the difference of the XRD patterns of two kinds of samples pretreated at 1073 K in a flow of N₂. Low-Mn showed the existence of three species; primarily MgO, MnO and a Mn-Mg-O solid solution while high-Mn had only the solid solution.
In order to examine the effect of the chemical compositions on the crystallite size, D and the lattice strain, η, the variations of the XRD-line widths of various Mn-containing samples were analyzed, employing the Hall's equation. The increases of Mn content increased η indicating that the formation of the solid solution made the crystal lattice strained, while D was independent of Mn content.
In the presence of Li in low-Mn, MnO and the solid solution disappeared, suggest ing that Mn was more highly-dispersed in MgO. The Hall's plots made it clear that the dose of 10 mol%-Li into high-Mn increased D not less than 10 times, as opposed to D of low-Mn with independency of Li content. These results manifested that Li played a role of the binder of the solid solution and not of Mn-dispersed MgO. The dose of Li moderated η by 65% for low-Mn and by 10% for high-Mn, and possibly the lattice strain was moderated by the substitution of Li⁺ for Mgi²⁺ⁱ.

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Primary conditions for preparation of single-phase fluormicas were investigated by solid state reactions using silica sand. Mica was obtained as a single phase from the mixtures of SiO₂: MgO: NaF: LiF =1.0: 0.5: 0.35-0.5: 0.25 at 725 °C for 3 h and at 750 °C for 1 h. Synthetic products were found to be 1Md type and expandable by uptaking monolayered water in the interlayer space. Furthermore, the effect of source of silica on the formation process was discussed. In the formation process of mica, the crystalline silicas such as a-quartz and cristobalite gradually decreased in amount by the reaction with some kinds of intermediate materials, and then were finally fixed in mica phase. When amorphous silicas, which easily transform into the crystalline silicas upon heating, were used as a silica source, singlephase mica was formed in a similar process as using crystalline silicas. However, in the case of amorphous silicas which crystallized slowly into cristobalite and α-quartz, single-phase mica was not obtained because intermediate materials would be existed in a definite temperature region.

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Reaction of guaiazulene with 3- (N, N-dimethylamino) propenal in the presence of phosphoryl chloride, followed by addition of sodium perchlorate, gave [3- (3-guaiazulenyl)propenylidene]dimethylammonium perchlorate (91%). This salt, when heated with a mixture of sodium methylate and quinoline in methanol, yielded 9-isopropyl-1-methylcyclopenta[ef]heptalene (87%). In the same manner, the corresponding dimethyl salt (97%) was obtained from 4, 6, 8-trimethylazulene, and was converted into 3, 5dimethylcyclopenta[ef]heptalene (86%). The yield of the cyclization step was fairly improved compared with that (57%) of Hafner's method, in which N-methylanilinium salt and sodium methylate were heated at the boiling point of chlorobenzene.
Nitration and trifluoroacetyla tion of 9-isopropyl-1-methylcyclopenta[ef]heptalene afforded 4-substituted products (20 and 23%), while its formylation led to 2- (13%), 4- (28%), 6- (14%), and 7-formyl derivatives (2%). Moreover, dimethylaminomethylation of 3, 5-dimethylcyclopenta[ef]heptalene occurred at 1-position (27%), but its nitration resulted in 7, 9-dinitro compound (8%). Thus the sites of electrophilic substitution were dependent on the reagents, different from the case of azulene compounds.

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Polymorphism of poly E bis( 4-isopropylphenoxy)phosphazenel-PB (4-Ip) PP has been investigated by DSC, X-ray diffraction measurements and electron microscopy. Orthorhombic (α-form) and monoclinic (β-form) of three-dimensional crystalline forms and two-dimensional pseudo-hexagonal mesophase (δ-form) are found depending upon the thermal history of specimens. The unit cell dimensions of the α-form and the β-form are estimated as a= 3.14 nm, b= 1.14 nm, c= 0.992 nm and a=2.45nm, b= 1.94 nm, c= 1.12 nm, γ =101.5°, respectively. The intermolecular distance in the mesophase is evaluated to be 1.64 nm. DSC measurements for the original PB (4-Ip)PP film exhibit the α→β and β→δ transitions at 86 °C and 120 °C, respectively. Whenever the 6-form PB ( 4-Ip)PP is cooled from the mesophase, it transforms into the α, β, or α+β forms depending upon the cooling rates. When the form specimen obtained by cooling from the mesophase is heated, the α-form transforms into the β at 83 °C, the β→δ transition occurs partially at 107 °C and the 6-form is established completely at 137 °C after the following heating. On the other hand, the fl-form resulted from the mesophase transforms into the δ-form sharply at 135 °C.

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Cellulose 3, 5-dinitrobenzoate (DNB-cellulose) with degree of substitution (DS) up to 2.65 was synthesized by the reaction of microcrystalline cellulose with 3, 5-dinitrobenzoyl chloride. The application of the DNB-cellulose to a liquid chromatography as a packing material was investigated in order to separate the five polyaromatic compounds: naphtharene, anthracene, phenanthrene, pyrene, and chrysene. The mutual separation ability of the packing material for the five samples has been found to be dependent on the DS by 3, 5-dinitrobenzoyl group. In this study the optimum DS was about 0.21 in the case using dichloromethane as the eluent. The effect of eluent composition was also investigated for the separation of the five polyaromatic compounds. The five samples were successfully separated from each other when the mixture of acetonitrile, dioxane and dichloromethane (5: 5: 90 in vol. ) was used as the eluent. The formations of charge transfer complex between DNB-cellulose and the polyaromatic compounds were deduced from the analysis of UV spectra of the mixture of methyl 3, 5-dinitrobenzoate as a model compound of DNB-cellulose and the polyaromatic compounds in dichloromethane.

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Bi-Ti complex alkoxide was prepared from bismuth acetate and titanium isopropoxide through solgel processing. The effects of solution additives [aqueous ammonia, hydrochloric acid, nitric acid and neutral (without acid and base)] and free additives on perovskite-like Bi₄Ti₃O₁₂ thin films developm ent were discussed. Addition of 0.01 mol water [neutral (without acid and base) ] for the Bi-Ti complex alkoxide solution developed more gradually the perovskite-like phase. The alkoxide solution containing acetate groups such as this Bi-Ti complex alkoxide solution could alter hydrolysis and condensation reaction thus change the gel structure of the deposited film. The change in gel structure may affect the crystallization behavior.

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We discussed the chemical features of major constituents i n precipitation collected in winter (Jan. and Feb. ) from April 1991 to March 1994 along the Sea of Japan on Honshu Island (mainland Japan) using a filtrating bulk sampler in cooperation with the Environmental Laboratories Association. In winter, the area along the Sea of Japan receives more precipitation than other areas and the pH is somewhat lower. Large amount of sea salt is deposited due to the northwestern winter monsoon. In spite of large precipitation amount, nss-SO₄^2- concentration in the precipitation was nearly equivalent to the average throughout Japan. As the NO₃^- concentration was less than the average, nss-SO₄^2- contributes to acidification of the precipitation more than NO₃^- Alkaline components, such as nss-Ca₂ and NH₄⁺, are lower than the average, especially nss-Ca²⁺ being only 0.54 times the average, and which meant that more hydrogen ions were left than in the case of the other areas. The precipitation amount is 1.9times the average and thus the deposition of all components, except Ca²⁺ and nss-Ca²⁺, is highest along the coast of the Sea of Japan. But, the features of the precipitation of western San-in which locate most western part of the area along the Sea of Japan was somewhat different from the other, which was similar to the feature of nothern Kyushu.

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The Eh-pH diagram (Pourbaix diagram) for N-H₂O system was constructed at 623 K based on the revised HKF (H. C. Helgeson, D. H. Kirkham and G. C. Flowers) equation. The fundamental thermodynamic data such as Cp° and 4 Δ° were derived from the HKF equation directly for ionic species, and from the combination of HKF equation and the Electrostatic Non-Electrostatic Model (H. C. Helgeson)for neutral species. Comparing the Eh-pH diagram at 623 K with that at 298 K, allboundaries between gaseous species were found to slant to the lower E with increasing pH. The stable regions of neutral species, i.e. NH₄OH (aq) and HNO₃(aq), expanded toward the neutral pH at 623 K, possibly because of the formation of ion pairs.

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Perfluorocarbons are promising, non-ozone depleting compounds as alternatives to 1, 1, 2-trichloro1, 2, 2-trifluoroethane (CFC113), the latter being accelerated to be phased out of precision cleaning systems. This is because perfluorocarbons have similar physical properties to CFC113. However, they hardly dissolve most compounds. We have found that perfluorooctane (PFO) and octamethylcyclotetrasiloxane (D4) are miscible with each other in a temperature range of 80∼103 °C. We anticipated that washing contaminants deposited on precision parts with D4 and the subsequent vapor phase cleaning with PFO would be promising. Various vapor phase cleanings of test panels contaminated with a model compound were examined. It has been found that the D4/PFO system is promising as an alternative to CFC113.

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The Products, 3, 3'-dibenzoyl-4, 4'-biphenyldiol (2) and 3-benzoyl-3, 3'-biphenyldiol (3) were obtained in the Fries rearrangement of 4, 4'-biphenyldiyldibenzoate (1) using anhydrous aluminium chloride (AlCl₃) as a catalyst in various solvent (Table 1)
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When o-dichlorobenzene was used as a solvent, the higheryield of 2 was obtained in the Fries rearrangement of 1 (Table 1, Fig.1). In this reaction, the produc t, 3 was given predominantly via intramolecular migration of a benzoyl group and elimination of other one, and then ortho-position of 3 underwent electrophilic attack of benzoylcation to give 2 (Scheme 1).

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Activated carbons were prepared from thiolignin with a variety of additives. The carbon with magnesium hydroxide (ratio to thiolignin 1.5 at 550 °C) had well developed pore-size distribution of around 10⁴nm in diameter. Although its BET specific surface area was as low level as 211 m²/g, it showed especially high adsorptivity toward sodium humate (molecular weight 5400) prepared by coal oxidation.
Contrary to this, when thiolignin was carbonized at 650 °C with 2.5 times of magnesiu m hydroxide, the obtained activated carbon showed 1025 m²/g of specific surface area, which was the similar level to the carbon obtained with sodium hydroxide. Its pore-size was distributed in the lower region (1.5 x 10³nm) than the former one, and it showed rather lower adsorptivity toward sodium humate.

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A new monoterpene glycoside were isolated together with known two diterpenoids and two triterpenoids from Rabdosia effusa HARA. These compounds were determined as carvacrol-3-yl glucoside, trichorabdal B, effusin, euscarphic acid, and hyptadienic acid. Structural determinations were made by spectroscopic data.

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The catalytic activity of polymeric t-amines prepared by the radical polymerization of N, N-dialkylaminoalkyl methacrylates on the urethane formation between phenyl isocyanate and 1-butanol was examined in comparison with that of triethylamine. The catalysis by poly[4-(N, N-dimethylamino)butyl methacrylate] was superior to that by triethylamine.

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