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US5491414A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of nuclear quadrupole resonance testing of integral spin quantum number systems

Assignee: BTG International Ltd
•
Filing: 1992-12-04
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Granted: 1996-02-13
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Expires: 2012-12-04
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Abstract

Abstract A method of Nuclear Quadrupole Resonance testing includes the steps of applying to a sample in which selected nuclei have an integral spin quantum number a series of at least three pulses of electromagnetic waves at a single radiofrequency to excite quadrupole resonance of the selected nuclei, and detecting responses at a plurality of times when echo response signals are expected to occur.

Inventors

  • 👤 John A. S. Smith
  • 👤 Julian D. Shaw

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 00:37
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/441

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 96 words
A method of NQR testing which includes the steps of: applying to a sample in which selected nuclei have an integral spin quantum number, a series of at least three excitation pulses of electromagnetic waves at a single radiofrequency to excite quadrupole resonance in said selected nuclei; and detecting echo response signals from said sample at a plurality of times; said series of at least three excitation pulses being arranged in time to generate a greater number of said echo response signals in a predetermined substance than a number of said at least three excitation pulses.
Claim 2
Independent Claim 96 words
A method of NQR testing which includes the steps of: applying to a sample in which selected nuclei have an integral spin quantum number, a series of at least three excitation pulses of electromagnetic waves at a single radiofrequency to excite quadrupole resonance in said selected nuclei; and detecting echo response signals from said sample at a plurality of times; said series of at least three excitation pulses being arranged in time to generate a greater number of said echo response signals in a predetermined substance than a number of said at least three excitation pulses.
Claim 3
Dependent Claim 14 words
A method as claimed in claim 1, wherein said echo response signals are summed.
Claim 4
Dependent Claim 43 words
A method as claimed in claim 1, wherein said step of applying said series of at least three excitation pulses and said step of detecting said echo response signals from said sample take place in an absence of any applied non-radiofrequency magnetic field.
Claim 5
Dependent Claim 69 words
A method as claimed in claim 1, wherein a first interval between a first pulse of said series of at least three excitation pulses and a second pulse of said series of at least three excitation pulses is different from a second interval between said second pulse of said series of at least three excitation pulses and a third pulse of said series of at least three excitation pulses.
Claim 6
Dependent Claim 68 words
A method as claimed in claim 1, wherein: said step of applying said series of at least three excitation pulses includes a step of applying three pulses at times 0, τ 1 and τ 2 , respectively; and said echo response signals are detected in periods embracing at least one of times 2τ 2 , τ 1 +τ 2 , 2τ 2 and 2τ 2 -2τ 1 .
Claim 7
Dependent Claim 43 words
A method as claimed in claim 5, wherein: τ 2 >2τ 1 ; and τ 1 , τ 2 , 2τ 1 , τ 1 +τ 2 , 2τ 2 -2τ 1 and 2τ 2 are times separate and distinct from one another.
Claim 8
Dependent Claim 15 words
A method as claimed in claim 5, wherein τ 1 is greater than one millisecond.
Claim 9
Dependent Claim 76 words
A method as claimed in claim 1, wherein: said pulses of said series of at least three excitation pulses are applied at times τ n , where n=0 to N and N is greater than or equal to two; and at least one of said pulses of said series of at least three excitation pulses being applied at a respective time 2τ m -τ m-1 , with m being greater than one for such respective time.
Claim 10
Dependent Claim 35 words
A method as claimed in claim 5, wherein a further pulse in said series of at least three excitation pulses is applied at a time 2τ n -τ n-1 , n being greater than one.
Claim 11
Dependent Claim 45 words
A method as claimed in claim 1, wherein, each of said series of at least three excitation pulses which is interposed between two other adjacent pulses of said series of at least three excitation pulses is not equally spaced between said two other adjacent pulses.
Claim 12
Dependent Claim 68 words
A method as claimed in claim 1, wherein: said step of applying said series of at least three excitation pulses includes a step of applying three pulses at times 0, τ 1 and τ 2 , respectively; and said echo response signals are detected in periods embracing at least one of times 2τ 1 , τ 1 +τ 2 , 2τ 2 and 2τ 2 -2τ 1 .
Claim 13
Dependent Claim 29 words
A method as claimed in claim 5, wherein a further pulse in said series of at least three excitation pulses is applied at time 2τ 2 -τ 1 .
Claim 14
Independent Claim 120 words
A method of NQR testing which includes the steps of: applying to a sample in which selected nuclei have an integral spin quantum number, a series of at least three excitation pulses of electromagnetic waves at a single radiofrequency to excite quadrupole resonance in said selected nuclei; and determining a plurality of times when echo response signals are expected to occur in said sample; detecting echo response signals from said sample at said plurality of times when echo response signals are expected to occur; said series of at least three excitation pulses being arranged in time to generate a greater number of said echo response signals in a predetermined substance than a number of said at least three excitation pulses.
Claim 15
Independent Claim 120 words
A method of NQR testing which includes the steps of: applying to a sample in which selected nuclei have an integral spin quantum number, a series of at least three excitation pulses of electromagnetic waves at a single radiofrequency to excite quadrupole resonance in said selected nuclei; and determining a plurality of times when echo response signals are expected to occur in said sample; detecting echo response signals from said sample at said plurality of times when echo response signals are expected to occur; said series of at least three excitation pulses being arranged in time to generate a greater number of said echo response signals in a predetermined substance than a number of said at least three excitation pulses.

References Cited (Backward Citations)

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SU757947A1 Cited
SU958935A1 Cited
GB2200462A Cited
US4887034A Cited
US5175499A Cited
GB2254923A Cited
US5206592A Cited
US5365171A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-02-12 1999-08-14 2000-02-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-02-12 2003-08-14 2004-02-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-02-12 2007-08-14 2008-02-13 $7700.00 Window Closed / Lapsed

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