2 0 0 0 OA MoO_3-B_2O_3フラックス蒸発法によるエメラルド結晶の育成
- 著者
- 大石 修治 望月 圭介 平野 眞一
- 出版者
- 公益社団法人日本セラミックス協会
- 雑誌
- 日本セラミックス協会学術論文誌 : Nippon Seramikkusu Kyokai gakujutsu ronbunshi (ISSN:18821022)
- 巻号頁・発行日
- vol.102, no.1185, pp.502-504, 1994-05-01
- 被引用文献数
- 3 6
The growih of emerald crystals by the flux evaporation method in the system Mo0_3 B_20_3 rs reported. The crys tal growth was conducted by heating a mixture of a so lute (3BeO・Al_2O_3・6SiO_2+1wt% Cr_2O_3) and a fiux (MoO_3 B_2O_3) at 1100℃, followed by holding at 1100℃ for 10, 20, 25 and 30h. The evaporation loss of flux decreased gradually with increasing amount of B_20_3 ad ded to Mo0_3 and increased with the holding time. The transparent emerald crystals were grown with the typi cal emerald green color in size up to I mm. The crystal size was dependent on the evaporation loss of flux. Hexagonal thin plate like crystals were grown from an Mo0_3 rich flux containing 0.15 0.60 wt% B_20_3. The plate like crystals were bounded by the {0001} and {1010} faces. In rare cases, the small {1120} faces ap peared. Crystals grown froun the MoO_3 flux were twelve sided prism in shape. Molybdenum trioxide con taining a small amount of B_2O_3 was found to be a suita ble flux for growing plate like crystals of emerald.
1 0 0 0 OA 炭化鉄(Fe3C)の合成と磁気的特性
- 著者
- 平野 眞一 田島 伸
- 出版者
- Japan Society of Powder and Powder Metallurgy
- 雑誌
- 粉体および粉末冶金 (ISSN:05328799)
- 巻号頁・発行日
- vol.37, no.3, pp.421-425, 1990-04-25 (Released:2009-05-22)
- 参考文献数
- 12
- 被引用文献数
- 3 2
The formation process and magnetic properties of Fe3C particles were investigated. Various iron oxides as a starting material were carbureted with CO gas in a furnace. Fe3C was formed at the reaction temperatures from 450 to 600°C. The partial pressure of CO gas was controlled by mixing with N2 gas to prevent the free carbon deposition due to the disproportionation of CO gas. Synthesized Fe3C particles were identified as a single phase by XRD and the weight change measurement. The saturation magnetization of Fe3C increased from 80 to 117 emu/g with the increase of the reaction temperature, while the coercive force decreased from 170 to 80 Oe with the increase of the reaction temperature.