权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Approach to rheology in the earth's crust based on the microstructure analysis

基于微观结构分析的地壳流变学方法

基本信息

批准号：
12640470
负责人：
KOTO Kichiro
金额：
$ 1.98万
依托单位：
The University of Tokushima
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640470/
关键词：
microstructure perovskite proton conductor ionic conductor oxide proton conductor rheology SrZrO_3 希土類

项目摘要

This work has been done to elucidate rheology of the solid state earth's crust based on the microstructure analysis by means of mineralogical and crystallographic approaches. It is expected that some silicates have perovskite-type structure under high pressure and at high temperature in the earth's crust. Especially proton conduction of solid is considered to play an important role in rheology because water is believed to exist in the earth's crust.Some perovskite-type sintered oxides such as lanthanide element-doped SrCeO_3, BaCeO_3 and SrZrO_3 show the proton conductivity in hydrogen-containing atmosphere at high temperature. The chemical stability of SrZrO_3-based oxide is much better and 10 mol % Yb-doped SrZrO_3 oxide shows the highest proton conductivity among SrZrO_3-substituted zirconium with lanthanide elements.The powder samples of 5 and 10 mol % Yb-doped SrZrO_3 oxides been synthesized by solid state reaction using the corresponding oxides as starting materials. The materials synthesized have been studied by X-ray powder diffraction, thermogravimetric analysis(TGA), differential thermal analysis and X-ray absorption fine structure spectroscopy. The orthorhombic unit cell volume of 10 mol % one increases monotonously with increasing temperature but exhibits a bent between 500℃ and 600 ℃ which is about 300K lower than that of 5 mol % one. This bent of the unit cell volume is considered to be due to a loss of oxygen, which is consistent with the result of a weight loss in TGA observed in the same temperature range. In addition the displacements of oxide ions were observed were observed in the Fourier syntheses followed by a loss of oxygen at high temperature.In conclusion the oxygen behavior plays an important role in the conduction mechanism of proton in solids.

本文从矿物学和晶体学的角度，以微观结构分析为基础，对固态地壳流变学进行了研究。预计在地壳中的高压和高温下，一些硅酸盐具有钙钛矿型结构。由于地壳中存在水，固体的质子导电性被认为在流变学中起着重要的作用，一些钙钛矿型烧结氧化物如镧系元素掺杂的SrCeO_3、BaCeO_3和SrZrO_3在高温含氢气氛中表现出质子导电性。以SrZrO_3基氧化物为原料，采用固相反应法合成了Yb掺杂量为5和10mol%的SrZrO_3基氧化物粉末样品。用X射线粉末衍射、热重分析、差热分析和X射线吸收精细结构谱对材料进行了表征。10mol%的单斜晶系晶胞体积随温度的升高而单调增加，但在500 ~ 600 ℃之间出现弯曲，比5mol%的单斜晶系晶胞体积低300 K左右。该晶胞体积的弯曲被认为是由于氧的损失，这与在相同温度范围内观察到的TGA中的重量损失的结果一致。此外，在傅立叶合成中还观察到氧离子的位移和高温下氧的损失，说明氧的行为在质子在固体中的传导机制中起着重要的作用。