Continuous-flow optical pumping NMR in a closed circuit system.
نویسندگان
چکیده
In a typical continuous-flow optical pumping setup, the chemical shift of xenon in the adsorbed phase depends on the gas flow rate due to warming of the sample surface by the gas stream. Calibration of the system using the (207)Pb resonance of solid lead nitrate is necessary to determine the actual sample temperature. Optimum pulse repetition rates are strongly affected by gas flow and spin-lattice relaxation rates. The interplay of flow and pulse repetition rate alters signal intensity ratios and may lead to the complete suppression of signals.
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ورودعنوان ژورنال:
- Journal of magnetic resonance
دوره 147 2 شماره
صفحات -
تاریخ انتشار 2000