NMR MAS probe with cryogenically cooled critical circuit components
US7151374B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 17, 2005 |
| Grant date | Dec 19, 2006 |
| Priority date | — |
| Expiry date | May 12, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/43
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A MAS probe offers a substantial improvement in signal to noise (S/N) in triple-resonance high-resolution (HR) magic-angle-spinning (MAS) NMR of samples near room temperature (RT) in high field magnets, especially where the RT shim bore is less than 55 mm. Critical circuit components other than the sample coils, including both high-power capacitors and inductors for one or more channels are located in a small, thermally insulated, cold zone immediately below the sample spinner assembly. Cooling these components to 100 K allows their thermal noise power to be conveniently reduced by a factor of three or more. Variable capacitors for fine tuning are located in an RT tuning zone below the cold zone. The circuit is designed such that the currents, voltages, and standing wave ratio (SWR) in circuit tuning elements in the RT tuning zone are relatively low, so rf losses and noise contributions below the cold zone may be only a few percent. The MAS probe is also compatible with magic angle gradients, automatic sample change, multi-nuclear tuning, variable temperature operation, field locking, and optical spin rate detection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.