Patent US5814989A successfully refreshed from Google Patents.
US5814989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for NQR testing
Assignee: CLEARWATER HOLDINGS NO 1 PTY Ltd
•
Filing: 1992-06-04
•
Granted: 1998-09-29
•
Expires: 2012-06-04
Abstract
Abstract A method and apparatus for imaging within a sample space an object containing quadrupolar nuclei comprises irradiating the object to excite nuclear quadrupole resonance, applying to the object a magnetic field gradient having a profile Bo(x) such that the square of the profile Bo(x))2 varies linearly with distance (x), detecting resonance response signals from the nuclei, and deriving an image from the response signals. A method of and apparatus for nuclear quadrupole resonance testing an object, and a method of and apparatus for detecting the presence of a particular substance containing a given species of quadrupolar nucleus, are also disclosed.
Inventors
- 👤 John Alec Syndney Smith
- 👤 Julian David Shaw
- 👤 Martin Blanz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:20
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/38; G01R33/381; G01R33/44; G01R33/441; G01R33/385
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
59 words
A method of detecting the presence of a particular substance containing quadrupolar nuclei, comprising: irradiating the substance to excite nuclear quadrupole resonance at a plurality of resonance frequencies, detecting response signals at each of the resonance frequencies, and providing an alarm signal in dependence on whether nuclear quadrupole resonance is detected at each of the plurality of resonance frequencies.
Claim 2
Independent Claim
59 words
A method of detecting the presence of a particular substance containing quadrupolar nuclei, comprising: irradiating the substance to excite nuclear quadrupole resonance at a plurality of resonance frequencies, detecting response signals at each of the resonance frequencies, and providing an alarm signal in dependence on whether nuclear quadrupole resonance is detected at each of the plurality of resonance frequencies.
Claim 3
Dependent Claim
42 words
A method according to claim 1 wherein the alarm signal is provided in further dependence on whether the relative intensities of the response signals at each of the plurality of resonance frequencies match those which would be expected for the particular substance.
Claim 4
Dependent Claim
74 words
A method according to claim 1 wherein, in a first test, the response signals from different resonances are summed together, and if, on the basis of this summation, a presence of the particular substance is detected to a given degree of probability, a second test is performed in which further irradiation is effected and the alarm signal is provided in dependence on whether resonance is detected at each of the plurality of resonance frequencies.
Claim 5
Dependent Claim
12 words
A method according to claim 1 wherein the resonance frequencies are well-resolved.
Claim 6
Dependent Claim
15 words
A method according to claim 1 wherein the resonance frequencies are components of a multiplet.
Claim 7
Dependent Claim
22 words
A method according to claim 1 wherein a lowest of the resonance frequencies is at least 50% of a highest resonance frequency.
Claim 8
Dependent Claim
26 words
A method according to claim 1 wherein the substance is repetitively irradiated to excite, during each repetition, nuclear quadrupole resonance at the plurality of resonance frequencies.
Claim 9
Dependent Claim
21 words
A method according to claim 7 wherein the duration of each repetition is less than five times the spin-lattice relaxation time.
Claim 10
Dependent Claim
65 words
Apparatus for detecting the presence of a particular substance containing quadrupolar nuclei, comprising: means for irradiating the particular substance to excite nuclear quadrupole resonance at a plurality of resonance frequencies, means for detecting response signals at each of the resonance frequencies, and means for providing an alarm signal in dependence on whether nuclear quadrupole resonance is detected at each of the plurality of resonance frequencies.
Claim 11
Dependent Claim
65 words
Apparatus for detecting the presence of a particular substance containing quadrupolar nuclei, comprising: means for irradiating the particular substance to excite nuclear quadrupole resonance at a plurality of resonance frequencies, means for detecting response signals at each of the resonance frequencies, and means for providing an alarm signal in dependence on whether nuclear quadrupole resonance is detected at each of the plurality of resonance frequencies.
Claim 12
Dependent Claim
49 words
Apparatus according to claim 9 wherein the means for providing the alarm signal is arranged to provide the signal in further dependence on whether the relative intensities of the response signal at each of the plurality of resonance frequencies match those which would be expected for the particular substance.
Claim 13
Dependent Claim
31 words
Apparatus according to claim 9 wherein the irradiation and detection means are arranged so that irradiation at one of the resonance frequencies begins before detection at another of the frequencies ends.
Claim 14
Dependent Claim
32 words
Apparatus according to claim 9 wherein the irradiation means is adapted to repetitively irradiate the substance so as to excite, during each repetition, nuclear quadrupole resonance at the plurality of resonance frequencies.
References Cited (Backward Citations)
GB1339076A
Cited
GB1329647A
Cited
GB1344084A
Cited
GB1357686A
Cited
GB1448939A
Cited
EP0122000A2
Cited
US4591789A
Cited
EP0277745A2
Cited
EP0426851A1
Cited
US5122748A
Cited
US5457385A
Cited
WO1992021987A1
Cited
US5233300A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-09-28 | 2002-03-30 | 2002-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-28 | 2006-03-30 | 2006-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-28 | 2010-03-30 | 2010-09-29 | $7700.00 | Window Closed / Lapsed |