The apparent vapor pressures of Sb₂S₃ in the molten Cu₂S-FeS-Sb₂S₃ ternary system were measured at atemperature of 1050°Cusing the transportation method. The above data were used to calculate the activityof Sb₂S₃ in the molten Cu₂S-FeS-Sb₂S₃ system. The activities of Cu₂S and FeS were evaluated in the binaryCu₂S-FeS and ternary Cu₂S-FeS-Sb₂S₃ systems using the Darken calculation method.
The activities of Sb₂S₃, Cu₂S and FeS in the Cu₂S-FeS-Sb₂S₃ system as well as the activities of Cu₂S andFeS in Cu₂S-FeS system exhibit negative deviation from the ideal behavior.

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In a series of studies of fundamental study on the kinetics of electroceramics processing by wet chemicalmethods, change in composition with temperature and reaction time for barium titanyl oxalates tetrahydratesin the cacination were characterized. Rapid formation of barium titanante was observed above 823 K, whichresulted from the reaction between titania and barium carbonate or barium oxide (s). A kinetic model wasproposed based on the experimental results. Thermogravimetric change of barium titanyl oxalatestetrahydrates during calcination could be reproduced and dynamics of barium titanate formation was success fully simulated using these kinetic parameters.

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New tetracarboxylic acid dianhydride, which was norbornane-2:3, 5:6-tetracarboxylic dianhydride (NDA) was prepared by treatment of dicyclopentadiene (DCPD) with CO and methanol in the presence of catalystsand oxidizing agent. The stereochemistry of NDA was determined by x-ray analysis as an endo-exo form. Forthe application of NDA to industrial fields and polymer science, polyimide films (1 and 2) based on NDA and aromatic diamines have been synthesized to investigate their heat resistance and percent of transmissionof light. The percent of transmission of 1 and 2 are over 80%, which should be desired for practicalapplications in the field of polymer engineering such as liquid crystal display (LCDs), whereas the polymers (3 and 4) obtained from aromatic tetracarboxyic dianhydride such as a pyromellitic dianhydride instead of NDA was deep yellow, which is not desirable for high qualified display materials. The percent oftransmission of the deep yellow polymers (3 and 4) show 48 and 63.9%, respectively. On the other hand, thermal decomposition temperature of 1 and 2 are 462 and 445°C, respectively, which are lower by almost 30-70°C of these 3 and 4, respectively. Nevertheless, the thermal stabilities of 1 and 2 are still better than in many other polyimides of high-performance polymers.

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Bis-alkoxylcarbonylation of dicyclopentadiene (DCPD) with carbon monoxide and a variety of alcoholsin the presence of palladium (II) catalyst and copper (II) salt as reoxidant have been studied andtricyclo [5.2.1.0^{2, 6}] dec-3-ene-8, 9-diester (TCDE) and tricyclo [5.2.1.0^{2, 6}] dec-3-ene-8, 9-dicarboxylic anhydride (TCDA) successfully were obtained for the first time. It is found that the double bond in the norboranenering can selectively be diesterified without affecting double bond in the cyclopentene ring, to obtain TCDE in good yield. When lower alcohols such as methanol and n-butanol are used, TCDE is obtainable in a highyield, however, branched alcohols such as sec-butanol or cyclohexanol and higher alcohol such as n-decanol gave TCDE in a yield ranging from 66% to 61%. Tert-alcohols such as tert-butanol or tert-amyl alcohol gave TCDA exclusively. It is the first example showing the selectively directly diesterifying one of the double binds in the DCPD.

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Mono (R) or (S)-3-hydroxy-3phenylpropanoic acid modified β-cyclodextrins (CyDs, 1 and 2, respectively) and their analogs of regioselectively bis-(R) and (S) 3-hydroxy-3-phenylpropanoic acid modified β-CyDs (3 and 4, respectively) have been synthesizd to investigate their enantiometric discrimination of D, L-isomers. These host compounds show composedof pure monomer emission with peaks around 300 nm and 340 nm, of which the intensities are decreased or increased when a host-guest complexation occurs. The extent of fluorescence variation with a guest is employed to display the sensing ability of those hosts. Monosubstituted CyDs such as 1 and 2 show relatively higher positive parameter values for the guests such as (β)-menthol (5, 6), (±)-camphor (7, 8), (±) 2bromopropionic acid (9, 10), and (±)-prolone (13, 14), although disubstituted derivatives such as 3 and 4 exhibit negative parameter values for the guests examined, when they are examined their ability at 300 nm.

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