U.S.-Korea Cooperative Research on NMR Phenomena in Solid H2and D2

美韩合作研究固体H2和D2中的NMR现象

• 批准号: 8820518
• 负责人: Horst Meyer
• 金额: $ 1.44万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-06-01 至 1993-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8820518&HistoricalAwards=false
• 关键词: U.S.; Korea; Cooperative; Research; NMR

This proposal requests funds to permit Dr. Horst Meyer, Department of Physics, Duke University, to pursue with Dr. Insuk Yu, Department of Physics, Seoul National University, for 24 months, an experimental and theoretical nuclear magnetic resonance (NMR) study of solid hydrogen and deuterium (H , HD, and D ). The research 2 2 will focus on (1) a better understanding of the NMR "solid echo" pattern in D single crystals, (2) a systematic study of 2 "stimulated echoes" in solid H and D that can give valuable 2 2 information on the molecular fluctuation rates, and (3) understanding the anisotropy of the NMR shift in the proton spectrum between H and HD. Solid H and D are each made up 2 2 2 of two molecular species forming a homogeneous mixture. These two species have rotational angular momentum (J=1) and (J=0). Mixtures of these species can be prepared in any proportion. The J=1 molecules have an electric quadrupole moment, while those with J=0 are spherically symmetric. Anisotropic forces between the J=1 particles produce orientational ordering at temperatures below about 3 degrees Kelvin. This ordering process in these molecular solids, analogous to dilute magnetic systems, is a function of the J=0 concentration. Above a critical concentration of J=1 equal to about 53 mole percent, there is a well defined transition to an ordered state. The research will attempt to provide a more quantitative understanding of the orientation ordering process in H , HD, and D and to explain anomalous behavior observed in 2 2 previous NMR studies of solid hydrogen. The U.S. and Korean collaborators are highly respected scientists who have records of successful research in the field of this project. Their collaboration in the past has led to several joint publications. Because Seoul National University does not yet have low temperature facilities, the work in Korea will be mostly theoretical, while that at Duke University will be both experimental and theoretical. The present project will allow the collaborators to combine their talents and interests for mutual benefit. This project is relevant to the objectives of the U.S.-Korea Cooperative Science Program which seeks to increase the level of cooperation between U.S. and Korean scientists and engineers through the exchange of scientific information, ideas, skills, and techniques and through collaboration on problems of mutual benefit. Korean participation in the project, including Dr. Yu's visits to Duke University, is supported by the Korea Science and Engineering Foundation (KOSEF).

该提案要求提供资金，允许霍斯特迈耶博士，部门 杜克大学物理系的教授，与Insuk Yu博士一起研究， 首尔国立大学物理系，为期24个月， 实验和理论核磁共振（NMR）研究 固体氢和氘（H，HD和D）。 研究 2 2 将重点放在（1）更好地理解NMR“固体回波” （2）系统地研究了三维单晶中的 2 固体H和D中的“受激回波”可以提供有价值的 2 2 关于分子波动率的信息，以及（3） 理解质子核磁共振位移的各向异性 H和HD之间的光谱。 固体H和D分别由 2 2 2 形成均匀混合物的两种分子种类。 这两 物种具有转动角动量（J=1）和（J=0）。 混合物 这些物质可以以任何比例制备。 J=1 分子具有电四极矩，而J=0的分子具有电四极矩， 是球面对称的 J=1之间的各向异性力 粒子产生取向有序的温度低于 大约3开氏度。 这些分子中的有序化过程 固体，类似于稀磁系统，是一个函数， J=0浓度。 高于J=1的临界浓度，等于 在约53摩尔%时，存在向 有序的状态。 这项研究将试图提供一个更 定量理解取向有序过程， H，HD和D，并解释在 2 2 固体氢的核磁共振研究。 美国和韩国的合作者都是备受尊敬的科学家 他们在这个领域有成功的研究记录 项目 他们过去的合作导致了几次联合 出版物。 因为首尔国立大学还没有 低温设施，在韩国的工作将大部分 理论上的，而在杜克大学将两者兼而有之 实验和理论。 本项目将允许 合作者联合收割机结合他们的才能和利益， 效益 该项目与《公约》的目标有关， 美国--韩国合作科学计划，旨在增加 美国和韩国科学家之间的合作水平， 工程师通过科学信息，思想， 技能和技术，并通过合作解决 互利 韩国参与该项目，包括博士。 俞敏洪访问杜克大学是由韩国科学院支持的 工程基金会（KOSEF）。