Device for heating a sample by microwave radiation
The present invention concerns a device for heating a sample by microwave radiation comprising a source of microwave radiation, a first waveguide for guiding said microwave radiation to an applicator space adapted to receive said sample to be heated, wherein said applicator space is defined by a terminal portion of said first waveguide and an initial portion of a second waveguide extending from said terminal portion of said first waveguide and being arranged at an angle with respect to said first waveguide.
1. A device for heating a sample by microwave radiation comprising:
a source of microwave radiation,
a first waveguide for guiding said microwave radiation to an applicator space adapted to receive said sample to be heated,
wherein said applicator space is defined by a terminal portion of said first waveguide and an initial portion of a second waveguide extending from said terminal portion of said first waveguide and being arranged at an angle with respect to said first waveguide,
said second waveguide adapted to block or dampen propagation of microwave radiation from said first waveguide into said second waveguide if no sample is present in the portion of said applicator space defined by said second waveguide, and
said second waveguide adapted to improve propagation of microwave radiation from said first waveguide into said second waveguide if a sample is present in the portion of said applicator space defined by said second waveguide.
2. The device of claim 1 , wherein said second waveguide extends essentially perpendicular from said terminal portion of said first waveguide.
3. The device of claim 1 , wherein said first waveguide is adapted to transmit a single mode of said microwave radiation generated by said source.
4. The device of claim 1 , wherein at least one of said first waveguide and said second waveguide is a rectangular waveguide.
5. The device of claim 1 , wherein at least one of said first waveguide and said second waveguide is a circular waveguide.
6. The device of claim 1 , wherein at least one of said first waveguide and said second waveguide is at least partially filled with dielectric materials exhibiting low absorbance for said microwave radiation.
7. The device of claim 6 , wherein said dielectric materials are selected from plastic materials.
8. The device of claim 1 , wherein said applicator space is adapted to receive a sample vessel.
9. The device of claim 8 , wherein said sample vessel is pressurizable.
10. The device of claim 8 , comprising means for stirring the sample in said sample vessel.
11. The device of claim 8 , comprising means for measuring the sample temperature in said sample vessel.
12. The device of claim 11 , comprising means for controlling the temperature of said sample.
13. The device of claim 11 , where said means for controlling the temperature of said sample are adapted to control the output power of said source of microwave radiation.
14. The device of claim 7 , wherein said plastic materials are selected from the group consisting of the following: polyolefins and fluoropolymers.