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Volume 1987 (1987)
- Issue 131 Pages 161-
- Issue 130 Pages 101-
- Issue 129 Pages 59-
- Issue 128 Pages 2-
Volume 1987, Issue 131
Displaying 1-6 of 6 articles from this issue
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Akira Kojima, Sugio Ohtani, Teruo Thuthumi, Shigeru Furukawa, Takeo Oh ...1987 Volume 1987 Issue 131 Pages 161-168
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSurface modification of PAN based carbon fiber (CF) by low temperature plasma was investigated to give high compatibility between CF and matrix in CF/cement composites (CFRC). The surface treatment of CF was carried out with O2, Ar and CF4 plasmas generated by radio frequency (13.56 MHz). The wettability of water on CF surface was remarkably modified to hydrophilic by O2 and Ar plasmas, and to hydrophobic by CF4 plasma. Furthermore, the CF surface was analyzed by ESCA and observed by SEM. It was found that the acidic group on the CF surface was formed by O2 plasma, and the surface fluorination on CF was carried out by CF4 plasma.
Then, the CF paper after plasma treatment was used for the preparation of CFRC. CFRC plates (6 mm in thickness) were prepared by the lamination of 12 sheets of CF paper preimpregnated with alumina cement paste, and were cured in water.
These CFRC's showed 2.0 g/cm3 in bulk density and 3.6 vol% in CF contents. The flexural strength of these CFRC's prepared from plasma-treated CF, was about 10-12 times higher than that of alumina cement hydrate. The CFRC plates prepared from CF paper pretreated in O2 and Ar plasmas exibited 1.8 times higher in flexural strength (60MPa) and 1.5 times larger in deflection compared with the CFRC without plasma treatment on CF. The flexural strength (74MPa) and deflection of CFRC plates prepared from CF4 plasma-treated CF, were the largest all.
Accordingly the low temperature plasma treatment of CF is regarded as an effective modifying method of CF for CFRC.View full abstractDownload PDF (1650K) -
Analysis of Oxydation Rate by Means of Langmuir-Hinshelwood Type EquationTakeshi Meguro, Kanji Tatemachi, Naochika Torikai, Tsutomu Wakasa1987 Volume 1987 Issue 131 Pages 169-177
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn order to investigate the reaction of carbon dioxide with carbon samples heattreated at various temperatures, integral gasification rates were measured in a batchwise reactor connected with circulation system. The carbon samples (10-20 mesh) used in this experiments were obtained by crushing the moldings made from pulverized pitch cokes and binder pitch. The moldings were baked at 1000°C (D-1000), 1400°C (D-1400), 1800°C (D-1800) and 2200°C (D-2200), respectively. The relations between partial pressures of carbon dioxide (Pco2) and carbon monoxide (Pco) and reaction rates (R) were calculated from the integral reaction rates and the results were applied to the follow-ing Langmuir-Hinshelwood type equation.
R=K1Pco2/(1+K2 Pco+K3 Pco2)
The rates in terms of R at Pco2 is nearly unity diminished with increasing heat-treatment temperatures (HTT) of carbon samples. The enthalpies of reaction in theoxygen exchange reaction (i. e., C*+CO2 _??_C (O)+ O) of D-1000, D-1400, D-1800 and D-2200 were 270, 260, 270 and 110 kJ/mol, respectively. It was considered that the affinity for dissociated oxygen of the active sites (C*) in D-1000, D-1400, D-1800 were relatively weak, while that of the sites in D-2200 was very strong. The activation energy of breakdown of surface oxide (C (O)) to CO increased with increasing HTT. Marked increase was found between 1800° and 2200°C.View full abstractDownload PDF (1347K) -
Tetsuro Yokono, Fumimitsu Kishimoto, Yuzo Sanada, Kazuo Makino1987 Volume 1987 Issue 131 Pages 178-180
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAn unique high frequency vibration autoclave has been constructed and applied inthe preparation of carbon microbeads from coal tar pitch/n-paraffin system.
The average particle size of the carbon microbeads obtained under high frequencyvibration has been 5.2μm. The carbon microbeads obtained without vibration have been relatively larger, with the average size of 8.2μm.View full abstractDownload PDF (430K) -
Yasuhiro Tanabe, Eiichi Yasuda, Shiushichi Kimura, Masaharu Okamine1987 Volume 1987 Issue 131 Pages 181-186
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFrit type antioxidants, whose major components were boron dioxide and boron dioxide plus silicon carbide, were coated on a fine grained graphite and two types of C/C composite as substrates. Oxidation weight loss of the substrates was measured. The antioxidants contacted well with the substrates after treated up to 1000°C and more. The boron dioxide type antioxidants protected oxidation effectively up to 1000°C, but not so effectively more than 1000°C. The boron dioxide added silicon carbide type antioxidant, however, was effective up to 1400°C.View full abstractDownload PDF (1516K) -
[in Japanese], [in Japanese], [in Japanese]1987 Volume 1987 Issue 131 Pages 187-198
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (1897K) -
[in Japanese]1987 Volume 1987 Issue 131 Pages 199-210
Published: October 25, 1987
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (2345K)
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