Oriented poly(vinylidene fluoride) (PVDF) films consisting of ␤ crystals were prepared by the solid-state coextrusion (SC) of a gel film near the melting temperature (T m ) and by conventional cold tensile drawing (TD) of a melt-quenched film. These films were annealed over the temperature range of 75-190°C (below and above the static T m ) while the sample length was kept constant or constant loads were applied. After annealing with the sample length kept constant, the dynamic Young's modulus markedly decreased because of the relaxation of oriented amorphous chains, as shown by infrared spectroscopy. In contrast, annealing under a constant load improved the chain orientation in both the crystalline and amorphous regions, resulting in an increase in the modulus from an initial 10.5 to 14.3 GPa for the SC and from an initial 3.3 to 4.8 GPa for the TD. The SC, annealed at 190°C with a constant load corresponding to an initial tension of 200 MPa, exhibited an extreme crystalline-chain orientation of 0.998 and a modulus of 14.3 GPa, among the highest values ever reported for PVDF. Although the remanent polarization (P r ) of the TD increased slightly from the initial 62 to 68 mC/m 2 , P r of the SC stayed constant at 100 mC/m 2 independently of the annealing conditions. This suggests that the P r value of 100 mC/m 2 approached the equilibrium value for this PVDF sample containing 3.5 mol % structural defects. Therefore, although the modulus and P r of the TD increased slightly with annealing, the maximum values achieved by annealing were markedly lower than those of the SC and annealed SC.

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A series of selenophene-substituted boron-dipyrrin (BODIPY) monomers and selenophene-linked BODIPY oligomers was synthesized. The synthesized BODIPYs show good absorption/emission properties in the red to near-infrared region. Furthermore, some of the selenophenyl BODIPYs are not only useful fluorophores but also good photosensitizers to produce singlet oxygen.

Fe‐iminobipyridine complexes ((RBPIAr,R′)FeBr2, RBPIAr,R′=iminobipyridine derivatives) were found to exhibit good catalytic activity for hydrosilylation of ketones. The highest TOF (turnover frequency) was obtained for the hydrosilylation of 2‐octanone with phenylsilane (4190 min−1). The reactions of various 4‐substituted acetophenone derivatives revealed that the introduction of an electron‐withdrawing group at the 4‐position retarded the reaction. The TOF of the hydrosilylation of 4‐chloroacetophenone with diphenylsilane was quite low (30 min−1), however the addition of a catalytic amount of Lewis base, especially pyridine, dramatically accelerated this hydrosilylation (980 min−1). Comparison of this additive effect for several N‐donor ligands revealed that the coordination ability of the N‐donor ligand was responsible for the acceleration. The rate determining step in the hydrosilylation of ketones appeared to be the reductive elimination of alkoxy and silyl groups from the iron center, which was facilitated by the coordination of N‐donor ligand to the iron. This coordination ability of the N‐donor ligand, however, inhibited olefin hydrosilylation. Addition of KOtBu instead of N‐donor also showed the same acceleration and inhibition effects on ketone and olefin hydrosilylations, respectively.

The voltage–current characteristics of glow discharges in gas mixture (N2:O2=8:2) at a pressure of 10 Torr were obtained with the discharge current up to 150 A. Parallel-plane electrodes with a diameter of 10.7 cm and a discharge chamber with co-axial geometry were used to produce glow discharge with high current. The glow discharge voltage was almost constant until the whole surface of the cathode was covered with glow, i.e., until the discharge current became 3.7 A in our experimental condition (a normal glow discharge mode). The voltage, however, increased with the current when the glow covered over the cathode (an abnormal glow discharge mode). The electron density in positive column of the high-current glow discharge was obtained to be 3×1011 cm−3 from Langmuir probe measurements.