Ab initio complete active space self-consistent field (CASSCF) and second-order multireference Möller−Plesset (MRMP2) calculations have been performed to examine the photochemical behavior of diphenylacetylene (DPA) theoretically. The stable structure of DPA in S0 (S0-geometry) is optimized to be D 2 h . DPA at S0-geometry is mainly excited into the S3(B1u) state and then relaxes into the stable geometry in the B1u state (B1u-geometry) which is characterized as a quinoid structure. The B1u-geometry further relaxes into the globally stable geometry in S1 (tS1-geometry) which takes a trans-bent form. Around tS1-geometry, DPA moves into the lowest triplet state through intersystem crossing and finally relaxes into the stable geometry in T1 with D 2 h . The vibrational analyses at the important conformations mentioned above are in good agreement with the experimental findings of time-resolved transient spectroscopy.

Due to the large generation of blast furnace (BF) slag, new recycling processes that produce valuable materials are required. The authors have focused on a hydrothermal treatment of BF slag using waste heat exhausted from iron-and steelmaking processes. Although BF slag contains Al 2 O 3 , which is well known to have a deteriorating effect on hydrothermal reactions, especially CaO-SiO 2 hydration, it can be successfully solidified by hydrothermal treatment above 523 K. We focused on the contribution of MgO in BF slag to the hydrothermal reactivity in the slag system. The hydrothermal solidification of synthesized CaO-SiO 2 -Al 2 O 3 and CaO-SiO 2 -Al 2 O 3 -MgO slags were investigated in the present work. The hydrothermal solidification behaviors of slags are discussed based on the degree and type of crystal formation during the hydrothermal process.KEY WORDS: blast furnace slag; hydrothermal reaction; hydrothermal hot pressing; flexural strength.

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ABSTRACT:The misciblity of ternary blends consisting of amorphous nylon (Am-Nylon)lpoly(methyl methacrylate) (PMMA)Ipoly(4-vinylphenol) (PVPh) at 190°C was investigated by differential scanning calorimetry (DSC),thermo-photometry, Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). In the ternary blends, more than 70-90wt% PVPh was required to cause miscibility between Am-Nylon and PMMA, and the experimental ternary diagram indicating symmetrically miscible regions was obtained. FT-IR results showed this miscibility was attributed to intermolecular hydrogen bonding interactions. Using stoichiometric equations, the equilibrium constant (Kc = 3.2) describing hydrogen bonding between the OH group of PVPh and amide group of Am-Nylon was determined from quantitative FT-IR analysis. The miscible region was affected by individual equilibrium constants (K;), since individual binary interaction parameters (Xii) were significantly larger than the critical value of Xii· The miscibility of Am-NyloniPMMA blends was enhanced by adding 20wt% PVPh to binary immiscible polymer. Recently, due to the industrial importance of multicomponent blends, the miscibility and morphology of ternary blends have been investigated. 1 -7 By ternary blends one could obtain more polymer composites than binary blends, having high ability and faculty. However, it is clear that the complexity of calculating phase diagrams, problems of experimental accuracy and interpretation of results of ternary blends increase dramatically over that of analogous binary blends.The phase behavior of ternary polymer blends involving strong specific interactions (hydrogen bonding), has only been studied by Coleman, Pomposo, and others. 8 -11 A binary association model which was suggested by Coleman et al., and has been extended to ternary hydrogen bonding polymer mixtures. This model was based on the suggestion to separate favorite 'chemical' specific interactions from unfavorite 'physical' ones. 12 -1 7 The free energy of mixing !lG m of ternary systems can be expressed in eq 1 by adding free energy (!lG:,H) of mixing based on the Flory-Huggins theory (2) where

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