Two types of novel dithieno[3,2-a:2’,3’-c]phenazine (dtpz) derivatives, bearing electron-donating π-conjugated side-arms at the 2,5- and 8,11-positions, were synthesized and their luminescence properties were discussed. The 8,11-disubstituted derivatives exhibited fluorescence in dichloromethane in the regions from yellow to red (photoluminescence wavelength λ_PL; 557-651 nm). Especially, 9-(2-ethylhexyl)-9H-carbazol-3-yl and 4-hexylthiophen-2-yl side-arms afforded red emission with high photoluminescence quantum yields (Φ_PL) of 0.75 (λ_PL; 616 nm) and 0.38 (λ_PL; 651 nm), respectively. Although the 2,5-disubstituted derivatives (λ_PL; 630-685 nm) exhibited more red-shifted fluorescence in dichloromethane than the 8,11-disubstituted derivatives, they are less emissive, showing Φ_PL of 0.07-0.23. All the developed dtpz derivatives showed positive solvatochromic behavior in photoluminescence, and red shifts of their photoluminescence spectra were observed as polarity of the solvent increased. From the Lippert-Mataga plots, their dipole moments were significantly enlarged upon photoexcitation, indicating that strong intramolecular charge transfer occurs upon electronic transition. Using the 8,11-disubstituted dtpz derivative with 9-(2-ethylhexyl)-9H-carbazol-3-yl side-arms as an emitting dopant, a poly(9-vinyl-9H-carbazole) (PVCz)-based OLED was fabricated. Yellow electroluminescence with the Commission Internationale de L'éclairage chromaticity coordinate of (0.53, 0.46) was observed, the spectrum of which was blue-shifted in comparison with photoluminescence of the emitting dopant in dichloromethane due to low polarity of the PVCz host.

Effects of stabilizer (poly(N-vinyl-2-pyrrolidone), PVP) concentration on the electrochemical performance of Au-Pt bimetallic (Au₄Pt) anode catalysts for direct glucose fuel cell (DGFC) have been investigated. In the cyclic voltammetry, the maximum current density was recorded at [PVP] / [metal] = 1 in molar ratio for the carbon supported metal nanoparticle catalysts at 5 wt% metal loading. At lower PVP concentrations, the current density decreased due to aggregation of metal nanoparticles, while at higher PVP concentrations, the current density also decreased, presumably due to loss of active surface area of the metal catalyst by passivating with the stabilizer. Also for the full cell systems, the maximum power density was recorded at [PVP] / [metal] = 1. When the optimal stabilizer condition was applied to the full cell system, the maximum power density of 12.7 mW cm^-2 at 0.38 V vs Ag | AgCl and the open circuit voltage of 0.85 V were recorded. Furthermore, a set of 10 stacked cells was able to light 6 LED lamps of total 1 W for over 60 h without flowing the glucose fuel. These results demonstrate that the present DGFC system can be applied as a power supply for LED illuminating systems.

In general, an energy state at a material interface is different from that in the corresponding internal region. This means that aggregation states and physical properties of polymer chains at the interface cannot be simply understood in an extension of their bulk information. We here present such examples at liquid and solid interfaces while exchanging the analytical methods.

A method is presented to prepare the thermosetting and thermoplastic highly transparent hybrid materials composed of ZrO₂ (diameter < 10 nm) and polymers. The method includes a direct transfer of nano-sized ZrO₂ particles of 4-6 nm diameter from water to toluene phase without any coagulation. The hydrophobic treatment of ZrO₂ nanoparticles was achieved by adding small amount of carboxylic acid as a dispersant, toluene, and methanol to water containing ZrO₂ particles, followed by successive gentle evaporations. Transparent toluene dispersion was successfully obtained by addition of carboxylic acids with the number of carbon atom higher than 4 and/or methacrylic acid. The bulk polymerization of vinyl monomers containing ZrO₂ nano-particles afforded optically transparent thermosetting and thermoplastic hybrid materials with a refractive index much higher than original polymer.

Textile products are produced through the steps of scouring → dyeing → soaping → (fixing) → finishing→ sewing (garment washing), and surfactant is utilized in almost all the steps. The basic performance of surfactants, such as emulsification, dispersion, wetting, penetration, cleaning, etc., contribute in many aspects. In addition, the required quality and function, along with the nature of the fiber materials, are evolving year by year, and surfactant plays a very important role in supporting this evolution in terms of technology. This article focuses on process chemicals such as scouring agents/ dyeing assistant auxiliaries (dispersion and leveling agent for polyester), oligomer removers and cotton fixatives, and those used for finishing processes such as flame retardants / water repellents/ water absorbing quick drying agents. We also introduce the roles of surfactants in each process and give application examples of interfacial chemistry. In addition, practical examples of the role and surface chemistry of the surfactant at each step are introduced.

Law Concerning the Evaluation of Chemical Substances and Regulation of Their Manufacture, etc. in Japan (this law) is the world's first notification legislation. In 1973, this law was established in response to the Kanemi oil poisoning symptoms, which was caused by a food poisoning by rice bran oil (Kanemi oil) with polychlorinated biphenyls (PCBs) contamination. In the rapid progression of the development of chemical substances, this law will play more important role in the hazard and risk assessment for chemical safety. We introduce the history of this law and each test method for chemical safety.