NMR MAS sealing sample cells and methods
US6054857A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 18, 1998 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Mar 18, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/307
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A cylindrical NMR sample cell is made from a first plastic material having Young's modulus Y.sub.1, tensile strength S.sub.1, and density p.sub.1 with precision outside diameter (OD) d.sub.4, wherein the outside diameter fits inside a ceramic NMR MAS rotor having modulus Y.sub.3 and density p.sub.3. The sample cell comprising a sample chamber with a concentric cylindrical opening at one end having inside diameter d.sub.2. A cylindrical plug is made from a second plastic material having modulus Y.sub.2, strength S.sub.2, and density p.sub.2 with plug outside diameter d.sub.1 to fit firmly inside the mouth of the cell, so as to seal the sample of density p.sub.4 inside the cell with inside cell diameter d.sub.3 when stationary and to seal when spinning at a high rate of speed inside the ceramic rotor. More-over, the following materials properties and relationships are satisfied: Y.sub.1> 0.8 GPa, Y.sub.1 <4 GPa, Y.sub.2 <3.4 GPa, S.sub.1 >8 MPa, S.sub.2 >3 MPa, p.sub.2 >880 kg/m.sup.3, p.sub.2 >p.sub.4, Y.sub.3 >Y.sub.2 >Y.sub.1, and p.sub.2 /Y.sub.2 >p.sub.1 /Y.sub.1. A dual-chamber cell is also disclosed to facilitate external lock.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.