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651.
652.
Carbonaceous materials containing nitrogen (C/N materials) were prepared by a pyrolysis of 2,3,6,7-tetracyano-1,4,5,8-tetraazanaphthalene (CAN). A C/N material prepared by the pyrolysis of CAN at 1070 K (CAN-1070 K) had a C/N atomic ratio of 3.0 and a non-crystalline carbonaceous structure with a BET surface area of 880 m2 g−1. The material CAN-1070 K showed large capacitances of 160–180 F g−1 and 110–120 F cm−3 in case of current density of 10 mA cm−2 (2 A g−1) by using three-electrode cell in 1 M H2SO4 aqueous solution, in comparison with that of activated carbon (160 F g−1 and 55 F cm−3) having BET surface area of 2300 m2 g−1. ESCA study indicated that pyridinic and quarternary nitrogen atoms existed in the C/N materials, which could result in producing a pseudo-capacitance in addition to the electric double layer capacitance. Also introduction of nitrogen into the carbonaceous material could enhance the wettability of material, which might also improve the capacitance. 相似文献
653.
Hiroyuki Nagai Masaaki Kawaguchi Keita Komiya Yoshio Kamiya Masakazu Washio Shigeru Kashiwagi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,265(1):82-86
A compact pico-second pulse radiolysis system has been developing at Waseda University for studying primary processes in radiation chemistry. The system is composed of a photo-injector system and a pico-second all-solid-state laser system. An infrared (IR) and an ultraviolet (UV) laser pulses are obtained from mode-locked Nd:YLF laser system and used for generation of the white light continuum as a probe light and the irradiation to the Cu cathode of a photo-cathode RF-gun, respectively. To improve signal-to-noise (S/N) ratio and time resolution of this pulse radiolysis system, we optimized both probe light and pump electron beam. As a result, our pico-second pulse radiolysis system has been enough to study the primary processes of radiation chemistry. The experimental results and the improvements of our system are described in this paper. 相似文献
654.
Takafumi Kawaguchi Hiroyuki Nishimura Kazunori Ito Takashi Kuriyama Ikuo Narisawa 《Polymer Composites》2003,24(1):181-191
The hot water resistance of three kinds of short glass fiber or glass bead‐reinforced plastics [polyphenyleneether (PPE), polyphenylenesulfide (PPS), and polyoxymethylene (POM)] was studied by hot water immersion testing, tensile testing and water‐hammer fatigue testing. It was found that the degradation of the strength was observed only for the reinforced plastics under hot water immersion and that the change of the tensile strength was most drastic in glass fiber‐reinforced PPS (GFPPS). Scanning electron microscope (SEM) observations of the tensile fracture surface revealed that the change in tensile strength was attributable to the deterioration of the interface between the glass fiber and the matrix resin. The results of acoustic emission analysis also supported the conclusion that the change in strength was due to the deterioration of the interface. Although the change in the tensile strength of glass fiber‐reinforced PPE (GFPPE) was small compared with that of GFPPS, debonding between the glass fiber and the matrix resin and surface cracks was observed on the surface of the GFPPE specimens. 相似文献