DNP apparatus

Patent metadata

Field	Value
Publication number	US-9739862-B2
Application number	US-201414489502-A
Country	US
Kind code	B2
Filing date	Sep 18, 2014
Priority date	Sep 26, 2013
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A DNP apparatus includes a cryostat ( 7 ) having an opening ( 8 ) and a loading path for a sample ( 1 ), the loading path extending from the opening to a sample receptacle ( 29 ), with a cryomagnet and a microwave source ( 2 ) as well as a configuration for supplying microwave radiation from the microwave source to the sample, which comprises a microwave path extending directly to the sample. The microwave path extends spatially separately from the loading path and the configuration for supplying microwave radiation has at least one microwave feed-through passing through one or more walls of the cryostat. The microwave path is incident on the sample from a direction opposite to the loading path or from a sideward direction at right angles to or at an inclination with respect to the axis of the loading path. This leads to simple and efficient polarization of the electron spins in the sample.

First claim

We claim:

1. A DNP (dynamic nuclear polarization) apparatus for performing a measurement on a sample, the apparatus comprising:
at least one cryostat having an opening and a loading path for loading the cryostat with the sample, wherein said loading path extends from said opening to a sample receptacle at a location of the sample in said cryostat;
a magnet coil disposed in said cryostat for generating a homogeneous magnetic field at said location of the sample during the measurement;
a microwave source for generating microwave radiation; and
a configuration for supplying said microwave radiation from said microwave source to the location of the sample, said configuration being disposed in said cryostat and comprising a microwave path extending directly to said location of the sample in said cryostat, wherein said microwave path extends spatially separately from said loading path, said configuration for supplying microwave radiation further comprising at least one microwave feed-through passing through one or more walls of said cryostat, wherein said microwave path is incident on said location of the sample from a direction opposite to said loading path or from a sideward location at right angles to or at an inclination with respect to an axis of said loading path.

2. The DNP apparatus of claim 1 , wherein said microwave feed-through causes attenuation of said microwave radiation of less than 6 dB, less than 2 dB or less than 0.5 dB.

3. The DNP apparatus of claim 1 , wherein material in an area of said feed-through passing through said cryostat walls comprises polytetrafluoroethylene (PTFE), sapphire, aluminum oxide and/or quartz.

4. The DNP apparatus of claim 1 , wherein a heat output by said microwave feed-through on said cryostat is less than 200 mW, less than 100 mW or less than 50 mW.

5. The DNP apparatus of claim 1 , wherein said microwave feed-through comprises at least one dielectric lens.

6. The DNP apparatus of claim 5 , wherein said dielectric lens has an insertion loss of 5 dB, of 2 dB, of 1 dB or of 0.5 dB.

7. The DNP apparatus of claim 5 , wherein said the dielectric lens is formed from a dielectric, from a dielectric having a dielectricity constant ∈ with 1≦∈≦15, from polytetrafluoroethylene (PTFE), from sapphire, from aluminum oxide and/or from quartz.

8. The DNP apparatus of claim 1 , wherein said configuration for supplying microwave radiation terminates at a separation d from the sample at the sample location in the cryostat of less than 10 mm, less than 5 mm or less than 1 mm.

9. The DNP apparatus of claim 1 , wherein said configuration for supplying microwave radiation comprises a dielectric wave guide.

10. The DNP apparatus of claim 9 , wherein said dielectric wave guide is formed from a dielectric having a dielectricity constant ∈ with 1≦∈≦15, of polytetrafluoroethylene (PTFE), of sapphire, of aluminum oxide and/or of quartz.

11. The DNP apparatus of claim 1 , wherein said configuration for supplying microwave radiation comprises at least one antenna, a horn-shaped antenna, an antenna array, a coupler and/or a power splitter.

12. The DNP apparatus of claim 1 , further comprising a configuration for supplying a solvent liquid which enables dissolving of the sample and generation of a hyperpolarized sample liquid.

13. The DNP apparatus of claim 12 , wherein the solvent liquid is supplied to the sample from a top location and microwave radiation is supplied to the sample from below.

14. The DNP apparatus of claim 12 , wherein the solvent liquid is supplied to the sample from a bottom location and microwave radiation is supplied to the sample from above.

15. Use of the DNP apparatus of claim 12 , for generating hyperpolarized liquid for NMR and/or MRI measurements.

Assignees

• Bruker Biospin Ag

Inventors

• Wilhelm Dirk
• Lohman Joost A B
• Hinderer Joerg
• Grubinger Hannes

Classifications

• G01R33/28 Primary

  Details of apparatus provided for in groups G01R33/44 - G01R33/64 · CPC title

• G01R33/5605 Primary

  by transferring coherence or polarization from a spin species to another, e.g. creating magnetization transfer contrast [MTC], polarization transfer using nuclear Overhauser enhancement [NOE] · CPC title

• G01R33/282 Primary

  Means specially adapted for hyperpolarisation or for hyperpolarised contrast agents, e.g. for the generation of hyperpolarised gases using optical pumping cells, for storing hyperpolarised contrast agents or for the determination of the polarisation of a hyperpolarised contrast agent · CPC title

• G01R33/30

  Sample handling arrangements, e.g. sample cells, spinning mechanisms · CPC title