The detection coil and preamplifier are cooled to cryogenic temperature to reduce thermal noise to an extremely low level, enabling measurement with sensitivity several times higher than that of conventional room temperature probes. Automatic tuning and matching is supported, so a wide variety of continuous measurements can be performed in combination with the auto-tuning unit.
JEOL offers three types of cryogenic probes for solution NMR:
- UC: UltraCOOL probe
- SCO: SuperCOOL MARVEL Open type
- SCC: SuperCOOL MARVEL Closed type
All probes are capable of controlling the sample temperature over a very wide range from -40°C to +150°C. The Probe Lifter and Probe Arm are available as optional accessories to alleviate probe exchange.
Features
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Type
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Cooling by
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Sample Coil
Temperature
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Features
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| UltraCOOL
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UC
|
He gas
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≒20K
|
Ultra high sensitivity due to cryogenic capability
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| SuperCOOL MARVEL
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SCC
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He gas
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≒50K
|
About 1/4 of the running cost of UltraCOOL probe
No need to fill the cooling system with liquid nitrogen
Higher sensitivity than the open type
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| SCO
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Liquid nitrogen
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≒77K
|
Reasonable installation and running costs
Uses liquid nitrogen as coolant
Liquid nitrogen can be refilled during NMR measurement
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UltraCOOL probe
The UltraCOOL probe is capable of ultra-sensitive measurement, which is a feature of cryogenic probes, as well as stable high-temperature measurement, which is necessary for analysis of polymers and other materials. It also supports the new high-speed automatic tuning and matching.
SuperCOOL MARVEL probe
The SuperCOOL MARVEL probe is available in two cooling methods: open type using a liquid nitrogen tank and circulating type using an air-cooled refrigerator. The open type does not require a refrigerator, so it is superior in terms of running cost. The circulating type, which has a higher cooling capacity and better sensitivity, does not require replenishment of the refrigerant and has a higher continuous operating capacity.
29Si Background-Free
JEOL cryogenic probes greatly reduce the
29Si background signal coming from the probe components. A background-free measurement is available for glass materials. The spectra below show that the background signal was greatly reduced without the sample tube, demonstrating that the most of background signals came from the sample tube.
29Si NMR spectrum of 10wt% water glass/D2O
29Si NMR spectra measured by the SuperCOOL MARVEL probe with a 5 mm PTFE sample tube. As no background signal appears around -100 ppm, signals on the high magnetic field side are clearly confirmed.
Probe Arm and Probe Lifter
Cryogenic probes cannot be raised or lowered by hand in the cooled state due to safety concerns, and hence it might be necessary to warm up cryogenic probes to room temperature before manipulating with them. However, you can replace the UltraCOOL probe or SuperCOOL MARVEL probe in cooled state by using the Probe Arm or the Probe Lifter. Also, though UltraCOOL and SuperCOOL MARVEL probes are heavier than room temperature probes due to their design, they can be easily exchanged using the Probe Arm or the Probe Lifter.