Contribution of structural defects to nucleation process of metastable phase

结构缺陷对亚稳相成核过程的贡献

• 批准号: 13640476
• 负责人: NAGASE Toshiro
• 金额: $ 1.98万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640476/
• 关键词: metastable phase; nucleation; planar defect; quartz; moganite; cristobalite; TEM; CL

Disordered stack ings are commonly 'observed in the metastable phase. In the cases of opal-CT and moganite, the disordered domains have following common features; (1) the stacking sequence are completely disorder without periodic sequences such as highly ordered polytypes; (2) the planar faults are parallel to each other in the disordered domain; (3) the domain of disordered stackings exhibits a thin and platy form, which elongates parallel to the planar defects; (4) the domains of well ordered stackings overgrew on the domain of disordered stackings with very sharp boundary between the two domains (5) The basal plane of the platyshaped domain of disordered stackings is parallel to a singular surface of the crystal, and the singular plane. The disordered, structure is caused by two-dimensional nucleation growth mechanism under highly supersaturated conditions. The results of observations suggest that important factors for formation of metastable phase are supersaturation degree and admissibility of crystal structure for defects.

在亚稳相中通常观察到无序的堆叠。在蛋白石ct和莫甘石病例中，无序结构域具有以下共同特征：(1)堆积序列完全无序，不存在高序多型等周期序列；(2)平面断层在无序域中相互平行；(3)无序堆积区呈薄片状，平行于平面缺陷延伸；(4)有序层域在无序层域上过度生长，且无序层域与无序层域的边界非常明显；(5)无序层域的基面与晶体的奇异面平行，奇异面与有序层域的基面平行。无序结构是在高度过饱和条件下由二维形核生长机制引起的。观察结果表明，亚稳相形成的重要因素是晶体结构的过饱和度和缺陷容许度。

项目成果

T.Hiraga, O.Nishikawa, T.nagase, M.Akizuki: "Morphology of intergranular pores and wetting angles in pelitic schists studied by transmission electron microscopy"Contrib.Mineral.Petrol.. 141. 613-622 (2001)

T.Hiraga、O.Nishikawa、T.nagase、M.Akizuki：“通过透射电子显微镜研究泥质片岩中的粒间孔隙和润湿角的形态”Contrib.Mineral.Petrol.. 141. 613-622 (2001)

T.Nagase, M.Abiko, M.Tanaka: "Quantitative analyses of Brazil twin defects in chalcedony by X-ray powder diffraction method."KEK Progress Report. 2003-1. 160 (2002)

T.Nagase、M.Abiko、M.Tanaka：“通过 X 射线粉末衍射方法对玉髓中的巴西孪晶缺陷进行定量分析。”KEK 进度报告。

T.Kubo, E.Ohtani, T.Kondo, T.Kato, M.Toma, T.Hoaoya, A.Sano, T.Kikegawa, T.Nagase: "Metastable garnet in oceanic crust at the top of the lower mantle"Nature. 420・6917. 803-806 (2002)

T.Kubo、E.Ohtani、T.Kondo、T.Kato、M.Toma、T.Hoaoya、A.Sano、T.Kikekawa、T.Nagase：“下地幔顶部洋壳中的亚稳态石榴石”自然420・6917。

T.Kubo et al.: "Metastable garnet in oceanic crust at the top of the lower mantle"Nature. 420・6917. 803-806 (2002)

T.Kubo 等：“下地幔顶部洋壳中的亚稳定石榴石”《自然》420・6917（2002）。

M.Akizuki, T.Kuribayashi, T.Nagase, A.Kitakaze: "Triclinic liddicaotite and elbaite in growth sectors from Madagascar"American Mineralogist. 86. 364-369 (2001)

M.Akizuki、T.Kuribayashi、T.Nagase、A.Kitakaze：“马达加斯加生长区的三斜利迪高铁矿和锂辉石”美国矿物学家。