Experimental and theoretical studies of trace defects in minerals and other Earth materials

矿物和其他地球材料中痕量缺陷的实验和理论研究

• 批准号: 169994-2013
• 负责人: Pan, Yuanming
• 金额: $ 3.5万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=593534
• 关键词: Experimental; theoretical; studies; trace; defects

Trace defects, including radiation-induced varieties representing incipient radiation damage, in minerals exert profound impacts on material properties such as color, density, rheology, stability, electrical and thermal conductivity, magnetism, seismic velocity, and many more. Trace defects in minerals and other materials also have a wide range of applications in Earth sciences from geochemical modeling to dosimetry, geochronology, remediation of heavy metalloid contamination, nuclear waste disposal, and mineral exploration. This research program is directed towards fundamental understanding of trace defects in minerals and other Earth materials, with emphasis on their electronic structures, magnetic properties, and novel applications. Scientific approach includes field-based investigations to identify trace defects of important geological applications and/or direct environmental relevance. Laboratory experiments are designed to complement field-based investigations and to provide synthetic materials for spectroscopic studies. Trace defects in selected minerals and their synthetic analogues are then characterized quantitatively by use of multiple analytical techniques, particularly electron paramagnetic resonance (EPR) spectroscopy and synchrotron X-ray absorption spectroscopy (XAS), and first-principles theoretical calculations. Specific research objectives for the next-funding cycle are: 1) experimental and theoretical studies of new radiation-induced defects in quartz, 2) uptake and speciation of heavy metalloids in common sulfates and phosphates, and 3) development of in-situ high-pressure-temperature EPR techniques for investigating iron spin dynamics in the Earth's mantle. This research program on the discovery and fundamental understanding of defects in minerals and related materials is unique in the Canadian Earth science community and is innovative in exploring the frontiers of both experiments and theory. Also, this research program provides an excellent opportunity for the training of highly qualified personnel in a multidisciplinary environment.

矿物中的痕量缺陷，包括代表早期辐射损伤的辐射诱发品种，对颜色、密度、流变性、稳定性、导电性和导热性、磁性、地震速度等材料特性产生深远影响。矿物和其他材料中的痕量缺陷在地球科学中也有广泛的应用，从地球化学建模到剂量测定、地质年代学、重金属污染修复、核废物处理和矿物勘探。该研究项目旨在从根本上了解矿物和其他地球材料中的痕量缺陷，重点是它们的电子结构、磁性和新颖应用。科学方法包括基于现场的调查，以识别重要地质应用和/或直接环境相关性的痕迹缺陷。实验室实验旨在补充实地研究并为光谱研究提供合成材料。然后，通过使用多种分析技术，特别是电子顺磁共振 (EPR) 光谱和同步加速器 X 射线吸收光谱 (XAS) 以及第一原理理论计算，对选定矿物及其合成类似物中的痕量缺陷进行定量表征。下一个资助周期的具体研究目标是：1）石英中新的辐射诱导缺陷的实验和理论研究，2）常见硫酸盐和磷酸盐中重金属的吸收和形态形成，以及3）开发原位高用于研究地幔铁自旋动力学的压力-温度 EPR 技术。这项关于矿物和相关材料缺陷的发现和基本理解的研究项目在加拿大地球科学界是独一无二的，并且在探索实验和理论的前沿方面具有创新性。此外，该研究项目为在多学科环境中培养高素质人才提供了绝佳的机会。