Powder X-ray Diffraction for Geosciences and Innovative Materials

粉末X射线衍射仪是现代材料和地球科学中不可缺少的强大分析工具。它允许建立设计下一代材料所需的结构-属性关系，是解锁采矿废物管理解决方案的关键，了解环境污染物循环，获取土壤的工程属性，以及高级建筑应用。渥太华X射线核心设施配备了一个带有铜源、衍射束单色仪和闪烁探测器的Ultima IV系统。然而，这种配置阻碍了申请者研究项目的进展。因此，这项提议旨在为该系统配备一个快速硅条探测器(Rigaku D/Tex Ultra)和一个温控样品室(Rigaku SHT1500)。申请者迫切需要这些组成部分来支持他们的研究和HQP培训的具体方面： 1.海默的研究集中在新一代稀土光学和磁性材料的设计上，包括化学控制合成和结构-性质关系的建立。D/Tex Ultra的低检测下限是检测和识别第二相以及将晶体结构与材料性能相关联所必需的。 2.Al的研究旨在通过将可溶的As_2O_3矿山废物转化为低溶解度化合物来防止天然水的污染。利用D/Tex Ultra和SHT1500色谱室，必须以较低的检测下限和快速的采集时间进行X射线衍射谱分析，以鉴定产物并量化反应动力学。 3.Fortin研究天然水铁石的性质及其对环境污染物循环的影响。天然水合铁中含有杂质。为了揭示这些杂质对污染物循环的影响，必须对处于自然水合状态的矿物进行X射线衍射分析，并在模拟季节变化的温度下进行。超灵敏探测器和惰性小室将使这一点成为可能。 4.Vanapalli试图了解如何利用微生物和细菌酶诱导的方解石沉淀来提高土壤强度和制定侵蚀控制措施。D/Tex Ultra的低检测下限是这项研究成功的关键。 5.Foruzanmehr的研究重点是用于先进建筑应用的纤维材料的改性。确定半晶态材料的结晶度指数是衡量这些材料中天然纤维降解程度的关键指标。如果没有D/tex检测器和SHT1500电离室，指标值就不准确和错误，这使得该设备成为迫切需要。 此外，通过扩展能力和增加样品吞吐量，将现有的改造成最先进的PXRD将使uOttawa的整个用户社区受益。

Powder X-ray diffraction (PXRD) is a powerful and indispensable analytical tool in modern materials and geosciences. It allows to establish structure-property relationship needed to design next-generation materials, is key to unlock solutions to waste management in mining, understand environmental contaminant cycling, access engineering properties of soil, and for advanced building applications. The uOttawa X-ray Core Facility houses a - Ultima IV system with a Cu source, diffracted-beam monochromator and scintillation detector. Yet, this configuration prevents progress for the applicants' research programs. Hence, this proposal aims to equip the system with a fast silicon-strip detector (Rigaku D/teX Ultra) and a temperature-controlled sample chamber (Rigaku SHT1500). The applicants urgently need these components to support specific aspects of their research and HQP training: 1. Hemmer's research focuses on the design of next-generation optical and magnetic rare-earth-based materials including chemically-controlled synthesis and establishment of structure-property relationships. The D/teX Ultra's low detection limits are needed to detect and identify secondary phases and to correlate crystal structure with material performance. 2. Al's research aims to prevent contamination of natural waters by transforming soluble As2O3 mine waste to low solubility compounds. PXRD must be conducted with low detection limits and rapid acquisition times to identify the products and quantify the reaction kinetics, enabled with the D/teX Ultra and the SHT1500 chamber. 3. Fortin studies the properties of natural ferrihydrite and how it affects environmental contaminant cycling. Natural ferrihydrite contains impurities. To unveil the effect of these impurities on contaminant cycling, XRD analyses must be conducted with the mineral in the natural hydrated state and at temperatures that simulate seasonal variations. The ultra-sensitive detector and the inert chamber will make this possible. 4. Vanapalli seeks to understand how Microbially- and Bacterial-Enzyme-Induced Calcite Precipitation can be used to improve the strength of soils and to develop erosion control measures. The D/teX Ultra's low detection limits are critical to the success of this research. 5. Foruzanmehr's research focuses on the modification of cellulosic materials for advanced building applications. Finding the crystallinity index of semi-crystalline materials is a key indicator for the degradation of natural fibers in these materials. Without the D/tex detector and SHT1500 chamber, index values are imprecise and erroneous, making the equipment an urgent need. Moreover, transforming the existing into a state-of-the-art PXRD will benefit the entire user community at uOttawa by expanding capabilities and increasing sample throughput.