H-1 Dynamic Nuclear Polarization in Supercritical Ethylene at 1.4 T

Journal Article · Wed Mar 01 00:00:00 EST 2000 · Journal of Magnetic Resonance

DOI:https://doi.org/10.1006/jmre.2000.2016· OSTI ID:15002688

Wind, Robert A ^[1]; Shi, Bai ^[2]; Hu, Jian Zhi ^[1]; Solum, Mark S ^[3]; Ellis, Paul D ^[1]; Grant, David M ^[3]; Pugmire, Ronald J ^[3]; Taylor, Craig M ^[4]; Yonker, Clement R ^[1]

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1. BATTELLE (PACIFIC NW LAB)
2. PNNL
3. Utah, Univ Of
4. DOE

H1 dynamic nuclear polarization (DNP) has been measured in supercritical ethylene in the pressure range 60-300 bar and in an external field of 1.4 T. A single-cell sapphire tube was used as a high pressure cell and powdered 1,3-bisdiphenylene-2-phenyl allyl(BDPA) free radicals were added and distributed at the wall of the cell. At all pressures the dominant DNP effect was a positive Overhauser enhancement, caused by proton-electron contact interactions at the fluid/solid radical interface. The observed enhancements varied from 12 at 67 bar to 17 at 300 bar. Besides the Overhauser enhancement, also a small solid state and thermal mixing enhancement were observed, indicating that part of the ethylene is absorbed at the radical surface for a prolonged time. These data indicate that DNP-enhanced NMR has the potential of extending the impact of NMR in research areas involving supercritical fluids.

• Research Organization: Pacific Northwest National Lab., Richland, WA (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 15002688
• Report Number(s): PNNL-SA-32121; JMARF3; KP1402010; TRN: US200418%%22
• Journal Information: Journal of Magnetic Resonance, Vol. 143, Issue 1; Other Information: PBD: 1 Mar 2000; ISSN 1090-7807
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
SUPERCRITICAL STATE
ETHYLENE
POLARIZATION
RADICALS
INTERFACES
OVERHAUSER EFFECT
NUCLEAR MAGNETIC RESONANCE
DNP
OVERHAUSER EFFECT
SUPERCRITICAL FLUIDS