炭素
Online ISSN : 1884-5495
Print ISSN : 0371-5345
ISSN-L : 0371-5345
2005 巻, 219 号
選択された号の論文の9件中1~9を表示しています
  • 稲垣 道夫, 松永 貴文, 津村 朋樹, 豊田 昌宏
    2005 年 2005 巻 219 号 p. 217-220
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    Carbon-coated TiO2 powders were prepared at 900°C in N2 flow to have different carbon contents. Their photoactivity was evaluated by the rate constant for the decomposition of methylene blue under the irradiation from ultraviolet and fluorescent lamps, and compared with commercially available photocatalyst P-25. The samples composed from about 10 mass% carbon and TiO2 with main crystalline phase of anatase showed the photoactivity comparable with P-25, even better, under both irradiation conditions.
  • Hidetaka Konno, Ryoko Matsuura, Hajime Kiyono, Akihiro Sudoh, Hiroki H ...
    2005 年 2005 巻 219 号 p. 221-225
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    Carbon micro-spheres doped with boron and nitrogen have been made from a chelate resin, in which N-methyl glucamate functional groups form ester with borate ions. Carbon spheres formed by heating at 1000-1600°C for 1h in argon were 140-340μm in diameter and the central ca. 1/3 of sphere was hollow. They contained 4.4-4.8mass% of boron, and B/C and N/C mole ratios of the sphere surface increased markedly with raising heat treatment temperature (HTT). Most of boron and nitrogen atoms in the surface layer of 1600°C product were in the form of >B-N< bonds. Hardness and elastic modulus including Poisson's ratio were highest for the spheres produced at 1000°C, 1.24GPa and 18.9GPa, respectively, and decreased with raising HTT. Generally, oxidation resistance of spheres in pure oxygen increased with raising HTT, which may be owing to the increased amounts of surface >B-N< bonds.
  • 森下 隆広, 鈴木 理恵子, 西川 哲男, 津村 朋樹, 稲垣 道夫
    2005 年 2005 巻 219 号 p. 226-231
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    Porous carbons with high surface area were successfully prepared from thermoplastic precursors, such as poly (vinyl alcohol) (PVA), hydroxyl propyl cellulose (HPC) and poly (ethylene terephthalate) (PET), mixing with MgO by the carbonization at 900°C in inert atmosphere. MgO in the carbonization products was dissolved out by using a diluted sulfuric or acetic acid. The pore structure of the carbons obtained was characterized by different analysis methods of adsorption/desorption isotherms of nitrogen at 77K.
    The carbons prepared from PVA had relatively high micropore volume and large microporous surface area, but those of HPC and PET were rich in mesopores. BET surface area of the carbons obtained could reach to a high value, 800-1000m2/g, even though any activation process was not applied.
  • 奥山 圭一, 加藤 純郎, 山田 哲哉
    2005 年 2005 巻 219 号 p. 232-237
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    A reentry vehicle having a blunt configuration is subjected to a severe aerodynamic heating environment when reenteringthe earth's atmosphere. An ablator is a type of heat shield material that can be used effectively in the reentry vehicle. In particular, an ablator made of phenolic carbon fiber-reinforced plastics (CFRP) is known to possess superior resistance against aerodynamic heating. Phenolic CFRP is pyrolyzed and carbonized by aerodynamic heating and is recessed by oxidation. Although the recession value has been calculated in theoretical analysis, whether the predicted value and the value obtained from an actual earth atmospheric reentry are in agreement has not been determined.
    In this study, the measured value of the surface recession obtained from an actual earth atmospheric reentry was compared with the predicted value based on theoretical analysis. Consequently, it was confirmed that both values were in good agreement. Therefore, it is possible to predict the thermochemical recession value of phenolic CFRP that reenters the earth atmosphere with high accuracy.
  • 奥山 圭一
    2005 年 2005 巻 219 号 p. 238-242
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    A chopped carbon cloth impregnated with a phenol resin that is compressed under an elevated temperature is termed the chopped CFRP. Thermal and mechanical properties of the chopped CFRP are nearly isotropic. Heated CFRP is carbonized because the internal resin undergoes thermal decomposition. Due to this thermochemical reaction, cavities in the form of minute cracks developed inside the chopped CFRP. Once these cavities are formed, the interior of the chopped CFRP exhibits non-linear stress-strain characteristics. The elastic modulus and thermal expansion rate of the CFRP in this state have not been described analytically in detail till date.
    In this study, the formation of these cavities due to thermal decomposition was assumed to damage the interior of the CFRP. Based on this assumption, the elastic modulus and thermal expansion rate of the chopped CFRP in the nonlinear region were analyzed by using either a damage multiplier or the reaction rate. The results of this analysis were in good agreement with the measured values. Therefore, this approach of analyzing the elastic modulus and thermal expansion rate of the chopped CFRP is appropriate.
  • Hiroya Kakegawa, Tomoya Satoh, Kenjin Higaki, Kazuya Nishimura, Hiroka ...
    2005 年 2005 巻 219 号 p. 243-245
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    The anodic oxidation durability of several PAN based carbon fibers heat-treated at 2000°C, 2400°C and 2800°C was measured.The improvement in anodic oxidation durability was observed for all the tested heat-treated carbon fibers. In two kinds of carbon fibers, the maximum durability was observed for the samples heat-treated at 2400°C. The reason of the appearance of the maximum value is estimated that dry and wet type of oxidation occurred simultaneously in this anodic oxidation.
  • Hiroya Kakegawa, Sigenori Kashimura, Manabu Ishifune, Yoshihiro Murai, ...
    2005 年 2005 巻 219 号 p. 246-248
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    Indirect surface oxidation of highly graphitized milled carbon fiber (CF) with NO3. generated by an anodic oxidation of NO3- gives hydrophilic CF (CF-OH). Carbon fiber reinforced plastics (CFRP) prepared by using this milled CF-OH resulted in the remarkable increase of bending strength, elasticity, and thermal conductivity.
  • 石川 哲浩
    2005 年 2005 巻 219 号 p. 249-254
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
    The number of Hybrid Vehicles, like ‘Prius, ’ has been growing in the market worldwide in order to help decrease CO2 emissions. And Toyota Motor Corporation began leasing a new generation fuel cell vehicle the FCHV (Fuel Cell Hybrid Vehicle) in December 2002. That vehicle includes a new variable voltage power electronics system and uses the Nickel Metal Hydride (Ni-MH) battery system from the Prius hybrid gasoline electric vehicle. This paper describes on-going efforts to model optimum secondary storage systems for future vehicles. Efficiency modelling is presented for the base Ni-MH storage system, an ultra capacitor system and a Lithium ion (Li-ion) battery system. The Li-ion system in combination with a new high efficiency converter shows a 4% improvement in fuel economy relative to the base system.
  • 稲垣 道夫
    2005 年 2005 巻 219 号 p. 260
    発行日: 2005/09/01
    公開日: 2010/06/28
    ジャーナル フリー
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