Dye-doped polymer composite thin films were prepared by physical vapor deposition. The host matrix was polymerized by evaporating n-octadecylacrylate monomer using electron-assisted deposition polymerization method. The guest dye, tris-(8-hydroxyquinoline) aluminum, was introduced into the host matrix by simple coevaporation. The chemical composition can be easily adjusted by controlling the deposition rate of host and guest materials. Thermal stability of the composite films was studied by means of electron microscopy and surface plasmon resonance measurement. It was suggested that the glass transition temperature of the composite film varies with the composition, and the composite films have higher thermal stability compared to the monolithic film of guest dye.

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To probe the carrier injection from Au source electrode into the channel of pentacene field effect transistors (FET), optical second harmonic generation (SHG) measurement is employed. SHG is enhanced at the off state due to Laplace electric field formation, whereas it is diminished at the on state. As the generation of SHG signal is in proportional to the electric field formed in the channel, we concluded that SHG measurement can probe the change of the electric field in the pentacene FET channel due to the injected and subsequently trapped holes.

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The thermochromic behavior of poly(2,5-dialkoxy-p-phenylene vinylene)s (ROPPV)s and poly(2,5-alkyl-p-phenylene vinylene)s (RPPV)s have been studied. The temperature dependence of optical properties and the variation of properties with the side chain length have been compared with those of poly(3-alkylthiophene)s (PAT)s. The difference of bandgap energy between PPV derivatives and PATs can be tentatively interpreted in terms of the main chain structure. The photoluminescence intensity of ROPPVs and RPPVs decrease monotonically with increasing temperature. To explain this mechanism, we speculate on the separation of the excited species due to the reduction of distance between polymer main chains and the enhancement of the overlap of π-electrons with the twist of polymer main chain. Furthermore, the interaction between polymer main chain and the oxygen atoms of alkoxy side chain plays an important role for the optical properties of ROPPVs.

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An annular helium plasma at atmospheric pressure was generated by the 2.45 GHz microwave power (∼1 kW) with Okamoto cavity, and the physical and analytical characteristics were summarized. The electron density and iron excitation temperature of high energy part for the He plasma were on the order of 10¹⁴/cm³ and 6,500 K, respectively. An aqueous solution with non-metal was injected into the plasma by the ultrasonic system with desolvation and condensation. Intense atomic and/or ionic emissions were detected and the detection limit of 100 ppb for F I (685.6 nm), 100 ppb for Cl II (479.5 nm), 150 ppb for Br II (487.5 nm), 1ppb for C I (247.9 nm), 2 ppb for P I (213.6 nm) and 0.02 ppb for Mg II (279.6 nm) and Ca II (393.4 nm) were obtained.

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