Claims
- 1. A system for detecting contaminants in a sample, comprising:
a concentrator for concentrating molecules of the contaminants in said sample; and a terahertz radiation detection system coupled to the concentrator for receiving the concentrated molecules for analysis.
- 2. The system of claim 1, wherein the concentrator comprises:
a pre-concentrator for performing initial separation of the molecules of the contaminants from the sample; and a heat exchanger for condensing and evaporating the separated molecules of the contaminants.
- 3. The system of claim 2, where the pre-concentrator further comprises:
a first fan for drawing the sample into the pre-concentrator.
- 4. The system of claim 2, where the concentrator further comprises:
a pump coupled to the heat exchanger and adapted for drawing the molecules of the contaminants from the pre-concentrator to the heat exchanger.
- 5. The system of claim 2, wherein the heat exchanger further comprises:
a thermal electric cooler for controlling the temperature of the heat exchanger.
- 6. The system of claim 1, wherein the concentrator is coupled to the detection system by a sonic orifice.
- 7. The system of claim 1, wherein said sample is drawn from the concentrator and through the detection system by a pump.
- 8. The system of claim 1, wherein the detection system comprises:
a radiation source for generating frequency modulated far infrared radiation; a low-pressure cavity coupled to the radiation source for receiving said sample; and a radiation detector coupled to the low-pressure cavity.
- 9. The system of claim 8, wherein the low-pressure cavity has one or more far infrared transmissive walls to allow the frequency modulated far infrared radiation to pass therethrough.
- 10. The system of claim 8, wherein the radiation detector is cryogenically cooled.
- 11. The system of claim 8, wherein the low-pressure cavity has:
a sample chamber for receiving said sample; a vacuum chamber; a terahertz transmissive window positioned between the sample chamber and the vacuum chamber; and a conductive grating disposed within the vacuum chamber.
- 12. The system of claim 11, wherein the low-pressure cavity further comprises:
a lid having a reflective surface positioned opposite to the terahertz transmissive window.
- 13. The system of claim 11, wherein the low-pressure cavity further comprises:
a collector positioned proximate to an end of the conductive grating for intercepting an electron beam passed over the conductive grating.
- 14. The system of claim 13, wherein the collector is coupled to a measurement device for measuring the energy of the electron beam.
- 15. The system of claim 14, wherein the measurement device is an ammeter circuit.
- 16. The system of claim 11, wherein the sample chamber further comprises:
a sample tube for containing a liquid in which said sample is suspended.
- 17. The system of claim 11, wherein the low-pressure cavity further comprises:
an input pipe coupled to the sample chamber for collecting radiation from an environment outside of the low-pressure cavity and funneling said radiation into the sample chamber.
- 18. The system of claim 12, wherein the lid is coupled to an actuator for controlling the position of the lid.
- 19. The system of claim 8, wherein the radiation source is an IMPATT multiplier.
- 20. A detector for detecting contaminants in a sample comprising:
a radiation source for generating frequency modulated terahertz radiation; a low-pressure cavity coupled to the radiation source for containing said sample; and a radiation detector coupled to the low-pressure cavity for measuring absorption of radiation by said sample for determining whether said contaminant is in said sample.
- 21. The detector of claim 20, wherein the low-pressure cavity has one or more far infrared transmissive walls to allow the frequency modulated far infrared radiation to pass therethrough.
- 22. The detector of claim 20, wherein the radiation detector is cryogenically cooled.
- 23. The detector of claim 20, wherein the low-pressure cavity comprises:
a sample chamber for receiving said sample; a vacuum chamber; a terahertz transmissive window positioned between the sample chamber and the vacuum chamber; and a conductive grating disposed within the vacuum chamber.
- 24. The detector of claim 23, wherein the sample chamber has:
a lid having a reflective surface positioned opposite to the terahertz transmissive window.
- 25. The detector of claim 23, wherein the low-pressure cavity further comprises:
a collector positioned proximate to an end of the conductive grating for intercepting an electron beam passed over the conductive grating.
- 26. The detector of claim 25, wherein the collector is coupled to a measurement device for measuring the energy of the electron beam.
- 27. The detector of claim 26, wherein the measurement device is an ammeter circuit.
- 28. The detector of claim 11, wherein the sample chamber further comprises:
a sample tube for containing a liquid in which said sample is suspended.
- 29. The detector of claim 23, wherein the low-pressure cavity further comprises:
an input pipe coupled to the sample chamber for collecting radiation from an environment outside of the low-pressure cavity and funneling said radiation into the sample chamber.
- 30. The detector of claim 24, wherein the lid is coupled to an actuator for controlling the position of the lid.
- 31. The detector of claim 20, wherein the radiation source is an IMPATT multiplier.
- 32. A method for detecting contaminant molecules in a sample, comprising:
introducing the sample into a first portion of a low-pressure cavity; applying terahertz radiation to the sample; and observing the interaction of the terahertz radiation with the sample, for detecting the presence of the contaminant molecules.
- 33. The method of claim 32, further comprising:
concentrating the sample to enhance contaminant molecule density prior to introducing the sample into the low-pressure cavity.
- 34. The method of claim 32, wherein the sample is introduced into the first portion of the low-pressure cavity in a gaseous state.
- 35. The method of claim 32, wherein the sample is introduced into the low-pressure cavity in a liquid state.
- 36. The method of claim 32, wherein the step of applying terahertz radiation to the sample comprises modulating the frequency of the terahertz radiation.
- 37. The method of claim 34, wherein the step of observing the interaction of the terahertz radiation with molecules in the sample comprises:
providing a conductive grating disposed in a second portion of the low-pressure cavity, wherein the second portion of the low-pressure cavity is physically isolated from the first portion by a terahertz transmissive window; passing an electron beam over the conductive grating, in close proximity to the conductive grating; and determining the amount of energy lost by the electron beam.
- 38. The method of claim 35, wherein the step of observing the interaction of the terahertz radiation with molecules in the sample comprises:
introducing a portion of the sample into a first liquid to form a first liquid solution; inserting the first liquid solution into a container disposed within the first portion of the low-pressure cavity; observing the rotational spectrum of the molecules in the first liquid solution; introducing a portion of the sample into a second liquid to form a second liquid solution, wherein the second liquid contains at least one binding agent for binding to the molecules in the sample; inserting the second liquid solution into the container disposed within the first portion of the low-pressure cavity; observing the rotational spectrum of the molecules in the second liquid solution; and comparing the rotational spectra of the first and second liquid solutions.
- 39. The method of claim 38, wherein the step of observing the rotational spectra of the first and second liquid solutions comprises:
providing a conductive grating disposed in a second portion of the low-pressure cavity, wherein the second portion of the low-pressure cavity is physically isolated from the first portion by a terahertz transmissive window; passing an electron beam over the conductive grating, in close proximity to the conductive grating; and determining the amount of energy lost by the electron beam.
- 40. The method of claim 34, wherein the step of observing the interaction of the terahertz radiation with molecules in the sample:
providing a conductive grating disposed in a portion of the low-pressure cavity; passing an electron beam over the conductive grating, in close proximity to the conductive grating; funneling radiation from an environment outside of the low-pressure cavity into the low-pressure cavity; and determining the amount of energy gained by the electron beam.
- 41. A method for concentrating contaminant molecules in a gaseous or liquid sample comprising:
providing the sample to a pre-concentrator to separate the molecules from the sample; cooling the separated molecules in a heat exchanger to condense the molecules; and heating the condensed molecules in the heat exchanger to evaporate the molecules.
- 42. The method of claim 41, further comprising:
combining the molecules with a transport medium to facilitate transportation between the pre-concentrator and the heat exchanger.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/471,381, filed May 16, 2003 (titled “Terahertz Source and Applications”), and of U.S. Provisional Patent Application No. 60/530,508, filed Dec. 18, 2003 (titled “An Autonomous Rapid Facility Chemical Agent Monitor Via Smith-Purcell Terahertz Spectrometry”), both of which are herein incorporated by reference in their entireties.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60471381 |
May 2003 |
US |
|
60530508 |
Dec 2003 |
US |