Magnetic resonance (MR, Nuclear Magnetic Resonance or NMR) is a safe, nonradioactive, and nondestructive measurement technique based on the interaction of matter with static and radio-frequency magnetic fields. Magnetic resonance can detect the amount of elements such as hydrogen, fluorine, aluminum, and phosphorus and also provide viscosity information. SwRI has multiple specialized MR systems in its laboratories to perform measurements on samples over a wide range of temperatures, magnetic field strengths, RF frequencies, and other operating conditions.