Understanding Surface-Mediated Hyperpolarization of Water and other Neat Liquids from Parahydrogen

在这个由化学系化学测量和成像项目资助的项目中，来自佛罗里达大学和爱荷华州州立大学的Clifford R Bowers教授和Wenyu Huang教授及其团队试图了解SWAMP效应（表面沃茨被仲氢磁化），最近发现的一种现象，它可以显著提高在水介质中通过磁共振进行分子分析的灵敏度，这是改善例如医学磁共振成像（MRI）的关键挑战。SWAMP效应可以提供某些类型的MRI所需的廉价，便携式和连续产生的“超磁化”水源，为通常使用的昂贵，高维护方法提供替代方案。因此，SWAMP效应可以促进偏远或贫困地区的医学诊断MRI。通过与佛罗里达大学的几个项目的协调，这些概念被改编为面向高中生的外展演讲。大学前教育和培训中心（CPET）。在爱荷华州，相关的外展活动包括科学展览和本科生和高中生参与适当的研究活动。该项目的灵感来自最近发现的表面介导的质子超极化的液体水，甲醇和乙醇的多相催化在Pt 3Sn金属间纳米颗粒（iNPs）包裹在介孔二氧化硅（Pt3Sn@mSiO2）。在理论的指导下，结构/活性相关性作为催化剂性质（例如表面结构、组成、粒度、封装壳终止）和反应条件（温度、磁场、溶剂组成（化学和同位素））的函数进行了系统研究。催化剂性质的变化是基于多相催化的公认原理，包括组成原子的d带中心和电负性性质。本项目的目标是（1）了解SWAMP效应的基础机制，（2）使用机制的理解来开发新的催化剂，以提高SWAMP过程的效率，（3）探索NMR信号增强对各种纯液体和溶液的通用性，以及（4）研究潜在的应用。研究和推广计划是由一个跨学科的化学家小组进行的？一位催化剂材料专家（黄文宇，爱荷华州州立大学），一位核磁共振波谱学家（拉斯鲍尔斯，佛罗里达大学），和一位计算化学家（格雷姆亨克尔曼，得克萨斯大学奥斯汀分校）。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In this project funded by the Chemical Measurements and Imaging program of the Chemistry Division, Professors Clifford R Bowers and Wenyu Huang and their groups at the University of Florida and Iowa State University seek to understand the SWAMP effect (surface waters are magnetized by parahydrogen), a recently discovered phenomenon which could significantly increase the sensitivity of molecular analysis by magnetic resonance in aqueous media - a key challenge for improving, for example, medical magnetic resonance imaging (MRI). The SWAMP effect could provide an inexpensive, portable, and continuously generated source of "hyper-magnetized" water needed for some types of MRI, offering an alternative to the expensive, high-maintenance approaches normally used. Hence, the SWAMP effect could facilitate medical diagnostic MRI in remote or impoverished areas. The concepts are adapted for outreach presentations to high school students through coordination with several programs in the University of Florida?s Center for Precollegiate Education and Training (CPET). At Iowa State, related outreach activities include science shows and involvement of undergraduates and high school students in suitable research activities.This project is inspired by the recent discovery of surface-mediated proton hyperpolarization of liquid water, methanol, and ethanol by heterogeneous catalysis over Pt3Sn intermetallic nanoparticles (iNPs) sheathed in mesoporous silica (Pt3Sn@mSiO2). Guided by theory, structure/activity correlations are systematically studied as a function of the catalyst properties (e.g. surface structure, composition, particle sizes, encapsulation shell termination) and reaction conditions (temperature, magnetic field, solvent composition (chemical and isotopic)). Variation of catalyst properties is based on well-established principles of heterogeneous catalysis involving the d-band center and electronegativity properties of the constituent atoms. The goals of this project are to (1) understand the mechanism underpinning the SWAMP effect, (2) use the mechanistic understanding to develop new catalysts to increase the efficiency of the SWAMP process, (3) explore the generality of the NMR signal enhancement on a variety of neat liquids and solutions, and (4) investigate potential applications. The research and outreach plans are being carried out by an interdisciplinary team of chemists ? a catalyst materials specialist (Wenyu Huang, Iowa State University), an NMR spectroscopist (Russ Bowers, University of Florida), and a computational chemist (Graeme Henkelman, University of Texas, Austin).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.