U.S.-China Cooperative Research (Chemistry): Dynamic Nuclear Polarization in Carbonaceous Solids

中美合作研究（化学）：碳质固体中的动态核极化

• 批准号: 9016637
• 负责人: Gary Maciel
• 金额: $ 2.66万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-11-15 至 1993-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9016637&HistoricalAwards=false
• 关键词: U.S.; China; Cooperative; Research; Chemistry

This is a two year collaborative project between Gary Maciel of Colorado State University and Ye Chaohui of the Wuhan Institute of Physics, Chinese Academy of Sciences. It is sponsored jointly by NSF and the Chinese Academy of Sciences. Research will focus on the continued development and application of dynamic nuclear polarization (DNP), a powerful electron.spin/nuclear.spin double.resonance technique that enhances the nuclear spin polarization in Nuclear Magnetic Resonance (NMR) experiments on materials containing both magnetic nuclei and unpaired electrons. DNP is especially important in the characterization of Chinese and U.S. coals and diamond.like carbon films prepared in Chinese and U.S. laboratories. For the coal studies, the striking differences between magnetic resonance properties measured for U.S. and certain Chinese coals will be examined in depth, and structural models will be explored for explaining both types of coals and these specific differences. In the diamond film studies, the nature of "defect" structures will be elucidated and related to film properties and preparation methods. The unusual field strength used in the 1.9 T DNP spectrometer in the Wuhan Institute of Physics will provide a good opportunity for elucidating fundamental details of the DNP phenomenon in these samples (via the field dependence of DNP properties) and for establishing the optimum magnetic field for DNP studies of typical carbonaceous solids.

这是科罗拉多州立大学的加里·马西尔（Gary Maciel）和中国科学院武汉物理研究所的叶朝辉之间为期两年的合作项目。 它由美国国家科学基金会和中国科学院联合主办。 研究重点是动态核极化 (DNP) 的持续开发和应用，这是一种强大的电子自旋/核自旋双共振技术，可增强含有磁核和不成对电子的材料的核磁共振 (NMR) 实验中的核自旋极化。 DNP 对于中国和美国的煤炭以及中国和美国实验室制备的类金刚石碳膜的表征尤其重要。 对于煤炭研究，将深入研究美国和某些中国煤炭测量的磁共振特性之间的显着差异，并将探索结构模型来解释这两种类型的煤炭和这些具体差异。 在金刚石薄膜研究中，“缺陷”结构的本质将被阐明，并与薄膜特性和制备方法相关。 武汉物理研究所 1.9 T DNP 光谱仪中使用的不寻常场强将为阐明这些样品中 DNP 现象的基本细节（通过 DNP 特性的场依赖性）以及为典型碳质固体的 DNP 研究建立最佳磁场提供良好的机会。