Purchase of X-ray powder diffractometer

购买X射线粉末衍射仪

• 批准号: 375301-2009
• 负责人: Raudsepp, Mati
• 金额: $ 5.79万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=412129
• 关键词: Purchase; ray; powder; diffractometer

We are requesting funds to purchase another X-ray powder diffractometer. In the short term, our capability to acquire data will significantly increase with two instruments, and in the long term, we will have the security of a backup instrument as the old one becomes increasingly unreliable. The principles of a powder diffraction are as follows. The relationship between X-ray wavelength, diffraction angle, and the spacing of planes of atoms in crystals is simple. Using a diffractometer, knowledge of the first two allows measurement of the latter. Two basic types of information can be obtained from the peaks in a powder diffraction pattern: (i) the peak positions are a function of the size and symmetry of the unit cell, and (ii) the peak intensities are a function of the types and arrangement of atoms in the unit cell. From these data we can identify the crystalline phases present in a powder, calculate the dimensions of the unit cells, assess the degree of strain in the structure, and determine the average crystallite size of all the phases contributing to the diffraction pattern. In addition, using the Rietveld method, we can accurately and precisely measure the relative abundances of all the phases present, including amorphous material. Such measurements are of crucial importance to mineralogy, petrology and the materials sciences in general. X-ray powder diffraction is an essential tool for the following projects: application of the Rietveld method to identify and measure the abundance of minerals in diverse geological, industrial and environmentally unfriendly materials, prediction of environmental impacts of mining activities such as acid-rock drainage, sequestration of anthropogenic CO2 in mine tailings, determining the structures of minerals that are presently unknown, the structural characterization of novel nanomaterials, alloys and ceramics, and to identify and characterize new catalysts relevant to Canada's natural gas and heavy oil processing industries. This instrument will allow the Electron-Microbeam/X-Ray Diffraction Facility at UBC to significantly improve the quantity, quality and stability of our services to researchers, and to the minerals and materials industry in Canada.

我们正在申请资金购买另一台X射线粉末衍射仪。从短期来看，有了两台仪器，我们获取数据的能力将大大提高，从长期来看，随着旧仪器变得越来越不可靠，我们将拥有一台备用仪器的安全性。粉末衍射的原理如下。X射线波长、衍射角和晶体中原子平面间距之间的关系很简单。使用衍射仪，前两者的知识允许测量后者。可以从粉末衍射图案中的峰获得两种基本类型的信息：（i）峰位置是晶胞的大小和对称性的函数，以及（ii）峰强度是晶胞中原子的类型和排列的函数。从这些数据中，我们可以识别粉末中存在的晶相，计算晶胞的尺寸，评估结构中的应变程度，并确定对衍射图案有贡献的所有相的平均微晶尺寸。此外，使用Rietveld方法，我们可以准确、精确地测量存在的所有相（包括非晶材料）的相对丰度。这种测量对于矿物学、岩石学和材料科学都是至关重要的。X射线粉末衍射是以下项目的重要工具：应用Rietveld方法来识别和测量各种地质、工业和环境不友好材料中的矿物丰度，预测采矿活动的环境影响，如酸性岩石排水，尾矿中人为CO2的封存，确定目前未知的矿物结构，新型纳米材料、合金和陶瓷的结构表征，并确定和表征与加拿大天然气和重油加工工业有关的新催化剂。该仪器将使UBC的电子微束/X射线衍射设备能够显著提高我们为研究人员以及加拿大矿物和材料行业提供服务的数量，质量和稳定性。