Relate NMR Relaxation Times of Pure Components and Mixtures with Viscosities and Diffusion through Application of Corresponding States

通过应用相应的状态将纯组分和混合物的 NMR 弛豫时间与粘度和扩散联系起来

• 批准号: 9004067
• 负责人: Riki Kobayashi
• 金额: --
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-01-01 至 1993-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9004067&HistoricalAwards=false
• 关键词: Relate; NMR; Relaxation; Times; Pure

A versatile NMR probe has been designed and constructed. This probe is capable of performing low signal to noise spin- lattice relaxation and diffusion coefficient measurements at pressures up to 600 atm over a temperature range of -20 to 200oC. The probe is also configured so that vapor liquid equilibrium can be established in the sample at these temperatures and pressures. In the immediate future the probe will be used to measure relaxation times (T1) and self diffusion coefficients in 13CO2 as a function of temperature and pressure. The only T1 measurements on this important fluid are the four isochores measured by Smith and coworkers (1986). Several investigators have measured the self- diffusion coefficient of CO2 over the temperature range accessible to the probe, but the measurements are confined to pressures less than 200 atm. After the pure CO2 measurements, mixtures of CO2 and n-hexadecane will be studied. This data will then be correlated with classical transport properties. This type of correlation remains relatively unexplored for mixtures. A global corresponding states treatment will also be attempted throughout this project. NMR can supply a wealth of information about the motions of molecules in all phases of matter. From the relaxation times, the rotational and translational motions may be investigated. The diffusion coefficients, measured by the spin-echo method, provide a means to investigate translational motions. In the past several years NMR imaging has been established as a valuable tool in the investigation of fluid flow in porous media. A major challenge in the usefulness of this technique lies in relating the NMR measurables to traditional thermodynamic and transport properties. The interrelationship is shown in Figure 1. The purpose of our current NMR program, is to further develop and quantify some of the relationships between NMR measurables, transport properties, and state variables. One area which would benefit greatly from the development of these relationships is the interpretation and quantification of NMR images. Practical use of NMR imaging requires a correlation to bridge the NMR data with traditional engineering analysis.

设计并制造了一种多功能核磁共振探针。 这 探针能够执行低信噪比自旋， 晶格弛豫和扩散系数测量. 压力高达600大气压，温度范围为-20 ℃至 200oC。 探针还被配置成使得蒸气液体 可以在这些温度下在样品中建立平衡。 温度和压力。 在不久的将来， 将用于测量弛豫时间（T1）和自 13 CO2中的扩散系数作为温度的函数 和压力 唯一的T1测量在这个重要的 流体是史密斯及其同事测量的四个等轴线 （1986年）。 一些研究人员测量了自我- CO2在温度范围内的扩散系数 可接近探头，但测量仅限于 压力小于200 atm。 在纯CO2测量之后， 将研究CO2和正十六烷的混合物。 该数据 将与经典输运性质相关。 这种类型的相关性仍然相对未被探索， 混合物。 全局对应状态处理还将 在整个项目中尝试。 核磁共振可以提供大量的信息， 分子在物质的各个阶段。 从弛豫时间来看， 可以研究旋转和平移运动。 用自旋回波法测量了扩散系数， 提供了一种研究平移运动的方法。 在 在过去的几年中，NMR成像已经被确立为 多孔介质中流体流动研究的重要工具 媒体 这项技术实用性的一个主要挑战是 在于将NMR可测量值与传统的 热力学和输运性质。 的相互关系 如图1所示。 我们目前的核磁共振项目的目的， 是进一步发展和量化一些关系 核磁共振测量、传输特性和状态 变量 有一个领域将大大受益于 这些关系的发展是解释和 NMR图像的定量。 核磁共振成像的实际应用 需要相关性来将NMR数据与传统的 工程分析