Structural Studies on High Temperature Inorganic Materials

高温无机材料的结构研究

• 批准号: 05044221
• 负责人: YOKOKAWA Toshio
• 金额: --
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Overseas Scientific Survey.
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05044221/
• 关键词: High Temperature Inorgainc Chemistry; High Temperature NMR Spectroscopy; High Temperature IR; VIS Spectroscopy; Molten Oxides; Magma; Glasses; Silicates

It was aimed at the present study to clarify the atomistic structures of high temperature materials, especially amorphous states including glassy and molten states, with the aids of various experimental methods. The development of apparatus for those studies was also subsidiarily tried. Test of the high temperature probe for NMR which have been developed in the both laboratories was one of the important issues. Here are described the final three themes and their present situations.1. The local structure around Na^+ ion in sodium bearing silicate melt^<23>Na NMR spectra in sodium silicate and aluminosilicate were observed up to 1700ﾟC. The composition dependence of ^<23>Na chemical shift was obtained. From the comparison of chemical shifts with that of crystals, number of the nearest order around Na ion was seven.2. IR/Visible absorption spectroscopy of iron bearing silicate glassesIt was aimed to observe extra absorption than ordinary d-d transition. A couple of preliminary test shows … More that at Fe_3O_4 content of as high as 10 mole%, absorption was observed at the visible range.3. Order-disorder dynamics of Spinel(MgAl_2O_4)It is known that Mg(at tetrahedral site at the ordered spinel) and Al(at octahedral site) tend to mix at high temperature. In previous works, only the quenched samples have been studied. In the present work, the direct measurement at high temperatures was carried out. The mixing was observed to start at around 700ﾟC. A sharp peak at the position of tetrahedral Al was found above 1400ﾟC implying very rapid chemical exchange.On the other hand, room temperature MAS-NMR of natural spinels which have been heated for various time intervals and then quenched, made it possible to evaluate the amount of Al at tetrahedral site as a function of the intervals.It may be worthy of note that in addition to the themes above mentioned, ^<17>O NMR of water containing high temperature-high pressure quenched albeit glass was initiated.In view of limited research periods, our visit to CNRS (Orleans) was just a initiation and inspiration of our project and future prospects are more important. Counter visit of French group to Japan by French project is highly desirable for that purpose. Less

本研究旨在借助各种实验手段，阐明高温材料的原子结构，特别是包括玻璃态和熔融态的非晶态。为这些研究开发仪器也是辅助性的尝试。对两个实验室研制的核磁共振高温探头的测试是其中的一个重要课题。本文介绍了后三个主题及其现状。在<23>1700 ℃以下观察到了硅酸钠和铝硅酸盐熔体中Na^+离子周围的局部结构。得到了^ Na化学位移与组分的关系<23>。从化学位移与晶体化学位移的比较可知，Na离子附近的最近阶数为7.含铁硅酸盐玻璃的红外/可见吸收光谱研究目的是观察比普通d-d跃迁更多的吸收。几个初步的测试节目 ...更多信息 当Fe_3O_4含量高达10mol%时，在可见光范围内观察到吸收.尖晶石（MgAl_2O_4）的有序-无序动力学研究发现，在高温下，处于有序尖晶石四面体位置的Mg和处于八面体位置的Al易于混合。在以前的工作中，只有淬火样品进行了研究。在本工作中，在高温下进行了直接测量。观察到混合开始于约700 ℃。在1400 ℃以上发现了四面体Al位置上的一个尖锐峰，这意味着非常快速的化学交换。另一方面，对天然尖晶石加热不同时间间隔然后淬火的室温MAS-NMR，使得有可能评估四面体位置上的Al量作为间隔的函数。值得注意的是，除了上述主题之外，天然尖晶石的~ 1H NMR还可以用于评估四面体位置上的Al量。在1400 ℃以上发现了四面体Al位置上的一个尖锐峰，这意味着非常快速的化学交换。另一方面，对天然尖晶石加热不同时间间隔然后淬火的室温MAS-NMR，使得有可能评估四面体位置上的Al量作为间隔的函数。可能值得注意的是，除了上述主题之外，天然尖晶石的~ 1H NMR还可以用于评估四面体位置上的Al量。在1400 ℃以上，天然尖晶石的~ 1H NMR可以用于评估四面体位置上的Al量。在1400 ℃以上，天然尖晶石的~ 1H NMR可以用于评估四面体位置上的Al量<17>。鉴于研究时间有限，此次访问法国国家科学研究中心（奥尔良）只是对我们项目的一个启动和启发，更重要的是对未来的展望。为此目的，法国项目组对日本的回访是非常可取的。少

项目成果

Y.Inagaki: "High temperature NMR studies of sodium borate : Multiexponential-quadrupolar relaxation" Bulletin of Magnetic Resonance. 15. 108-111 (1993)

Y.Inagaki：“硼酸钠的高温核磁共振研究：多指数四极弛豫”磁共振通报。

C.Bessada: "^<29>Si MAS-NMR in lead silicates" Journal of Non-crystalline Solids. 168. 76-85 (1994)

C.Bessada：“硅酸铅中的^ 29 Si MAS-NMR”非晶固体杂志。

Y.Inagaki: "High temperature NMR studies of sodium borates:Multiexponential-quadrupolar relaxation" Bulletin of Magnetic Resonance. 15. 108-111 (1993)

Y.Inagaki：“硼酸钠的高温核磁共振研究：多指数-四极弛豫”磁共振通报。

J.-P.Coutures (D.Massiot, P.Florian and B.Cote): Wiely and Sons. High and very high temperature ^<17>O and ^<27>Al nuclear magnetic resonance on liquid alumina and silica bearing oxides., in press (1994)

J.-P.Coutures（D.Massiot、P.Florian 和 B.Cote）：Wiely and Sons。

H.Unuma: "Molecular Dynamics Study of Na-Si-O-N Oxynitrite Glasses" Journal of American Ceramic Society. 76. 1308-1312 (1993)

H.Unuma：“Na-Si-O-N 氧亚硝酸盐玻璃的分子动力学研究”美国陶瓷学会杂志。