巻号一覧
1991 巻 (1991)
- 150 号 p. 266-
- 149 号 p. 191-
- 148 号 p. 134-
- 147 号 p. 57-
- 146 号 p. 2-
1991 巻, 146 号
選択された号の論文の7件中1～7を表示しています
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北岡 猛志, 足立 正和, 北村 直之, 藤井 禄郎1991 年 1991 巻 146 号 p. 2-7
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーElectrical resistance of a composite material containing highly conductive graphite flakes is investigated using a computer simulation method in order to improve the electric conductivity.
This simulation shows that resistance of mixture composed of graphite flakes and resin decreases markedly at a certain volume fraction of graphite in resin in same manner as experimental results. Increase of aspect ratio of dispersed graphite flakes decreases a transition threshold and increases the electric conductivity at percolation state. Therefore it is deduced that the electrical conductivity is increased by the introduction of small amount of graphite having a large aspect ratio into resin.抄録全体を表示PDF形式でダウンロード (662K) -
山本 清志, 鞠谷 雄士, 高久 明1991 年 1991 巻 146 号 p. 8-14
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーA continuous process for heat-treating a carbon fiber tow by directly passing electric curren through the tow was developed, and by this process a polyacrylonitrile-based carbon fiber tow which was prepared at a highest temperature of about 1250°C was heat-treated. Heat-treatments of two types were made; one employing a reflector covering the heat-radiating zone of a tow, and the other without a reflector. The structural parameters characterizing the stacks of carbon layer, such as interlayer spacing, sizes and orientation, and the mechanical propertie of the carbon fibers heat-treated by direct currenting were evaluated as a function of surfac temperature of tow during heat treatment over the range of 1000 to 2000°C. A considerable heat-loss by radiation from the tow surface is expected during heat-treatment by direct currenting. Therefore an effective heat-treatment temperature in the inside of tow will be lower for the heat-treatment with a reflector than that without a reflector if the surface temperature of tow is constant. The structural parameters versus surface temperature relations for the tow heat-treated with a reflector differed from those for the tow heat-treated without a reflector. These results were explained by considering an effective heat-treatment temperature of tow. Differences in density and linear density between the tows heat-treated with and without a reflector could not be explained by the effective heat-treatment temperature, and seemed to be caused by a certain factor proper to the present heat-treatment method. The tensile modulus after making a correction on density increased almost linearly with increasing orientation of the stacks. The tensile strength decreased with increasing heat-treatment temperature in a similar manner reported for carbon fibers heat-treated by a conventional method.抄録全体を表示PDF形式でダウンロード (902K) -
神谷 寛一, 渥美 尚勝, 那須 弘行1991 年 1991 巻 146 号 p. 15-21
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーThe TiO2 coating films were applied to the artificial graphite plates through the sol-gel route using the dip coating technique. The TiO2 sol for the dip-coating was prepared by hydrolyzing titanium tetra-iso-propoxide in ethanol. The addition of HCl or diethanolamine was effective for stabilizing sols.
The TiO2 films thus obtained was heated to 1100°C in the.flow of NH3 gas to form titanium nitride which was still 'nonstoichiometric, but colored in brownish yellow. Relatively high adhesion of the film to the graphite was achieved. The nitridation process of the sol-gel derived TiO2 films was investigated.抄録全体を表示PDF形式でダウンロード (4707K) -
斎藤 保, 野村 真三, 今井 久1991 年 1991 巻 146 号 p. 22-26
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーImage analysis method was used to measure the radial thermal expansion coefficient of carbon fiber. Diameter of the carbon fiber was determined at each temperature up to 1000°C, by the analysis of SEM image introduced into a image analyzer. The thermal expansion coefficient was also obtained from calculation of the Bacon's equation, in which the orientation function measured by X-ray method was used with the thermal expansion coefficients of single crystal reported in literature. There was an acceptable agreement between the thermal expansion coefficients obtained by the two different ways. It was shown that the analysis of SEM image was an useful method to measure the radial thermal expansion coefficient of carbon fiber.抄録全体を表示PDF形式でダウンロード (805K) -
溶剤共存下での改質持田 勲, 中村 宗弘, 光来 要三1991 年 1991 巻 146 号 p. 27-32
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーCoal Tar based mesophase pitch was heat-treated together with polyvinylchloride (PVC) in solvent at a temperature range of 265 to 400°C to prepare carbon fiber precursor pitch of better quality. Modification provoked the thermal decomposition and dehydrochlorination of PVC which initiated alkylation, alkylbridging, and condensation reactions of molecules in the pitch, but such modification increased the amount of the benzene insoluble but quinoline soluble fraction without marked rises of softening and spinning temperatures, improving the stabilization reactivity of the pitch fiber and mechanical properties of resultant carbon fiber. Accelerated oxygen up-take by modification reflecting the increase of alkyl groups and enlarged molecular size in the modified pitch may shorten the time necessary for the complete stabilization.抄録全体を表示PDF形式でダウンロード (778K) -
足立 正和, 塩山 洋, 成澤 雅紀, 池田 茂, 辰巳 国昭, 相馬 勲, 磯崎 秀夫, 江川 和則, 久徳 博文, 田那村 武司1991 年 1991 巻 146 号 p. 33-36
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーElectrical resistivity of graphite is presented in the temperature range 900-2800K. In an atmosphere of nitrogen, electrical resistivity of isotropic graphite IG-110 increases with an increase in temperature. On the other hand, the temperature dependence of electrical resistivity in an atmosphere of argon is different: a significant decrease of electrical resistivity was observed above ca. 2400K. It was suggested that argon was not inert at temperatures above about 2400K, and affected the resistivity of graphite through some ionization or other reactions.
This atmosphere dependence of the electrical resistivity at elevated temperatures is thought to be generall phenomenon in measuring the resistivity of graphite, because the atmosphere dependence was also observed for other artificial graphites.抄録全体を表示PDF形式でダウンロード (494K) -
大岡 紀一1991 年 1991 巻 146 号 p. 37-49
発行日: 1991/02/05
公開日: 2010/06/28
ジャーナル フリーPDF形式でダウンロード (1455K)
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