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US3936633A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of determining lanthanidies in a transition element host

Assignee: Energy Research and Development Administration ERDA
•
Filing: 1975-01-16
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Granted: 1976-02-03
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Expires: 1995-01-16
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Abstract

Abstract A phosphor composition contains a lanthanide activator element within a host matrix having a transition element as a major component. The host matrix is composed of certain rare earth phosphates or vanadates such as YPO 4 with a portion of the rare earth replaced with one or more of the transition elements. On X-ray or other electromagnetic excitation, trace lanthanide impurities or additives within the phosphor are spectrometrically determined from their characteristic luminescence.

Inventors

  • 👤 Edward L. De Kalb
  • 👤 Velmer A. Fassel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 02:09
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7766; C09K11/7777; G; G01; G01N; G01N23/00; G01N23/22; G01N23/223; G01N2223/00; G01N2223/07; G01N2223/076

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 51 words
A method of detecting trace quantities of fluorescing lanthanides in a transition element alloy comprising: A. preparing a host composition including yttrium and a transition element; B. exciting the fluorescing elements within said composition with electromagnetic radiation; C. spectrometrically analyzing the resulting fluorescent radiation to quantitatively determine trace quantities of lanthanides.
Claim 2
Independent Claim 51 words
A method of detecting trace quantities of fluorescing lanthanides in a transition element alloy comprising: A. preparing a host composition including yttrium and a transition element; B. exciting the fluorescing elements within said composition with electromagnetic radiation; C. spectrometrically analyzing the resulting fluorescent radiation to quantitatively determine trace quantities of lanthanides.
Claim 3
Dependent Claim 48 words
The method of claim 1 wherein said host composition is prepared by forming a mixture of a transition metal compound, Y 2 O 3 , and (NH 4 ) 2 HPO 4 ; and heating said mixture to a temperature below the melting point of the lowest-melting component.
Claim 4
Dependent Claim 39 words
The method of claim 2 wherein a nucleating agent consisting of Na 4 P 2 O 7 is added to said mixture of transition metal compound, Y 2 O 3 , and (NH 4 ) 2 HPO 4 .
Claim 5
Dependent Claim 41 words
The method of claim 1 wherein said host composition is prepared with a known quantity of a known fluorescing lanthanide to provide fluorescent radiation on X-ray excitation for spectrometrical comparison with fluorescent radiation from said fluorescing lanthanides to be quantitatively determined.
Claim 6
Dependent Claim 59 words
The method of claim 1 wherein said transition element alloy is an iron alloy and said host composition is prepared by electrolytically dissolving said iron alloy in acid solution, adding yttrium into said solution, evaporating said solution to dryness to form a dehydrated mixture and heating said mixture to a temperature below that required to effect a sintering condition.

References Cited (Backward Citations)

US3859525A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-02-02 1979-08-04 1980-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-02-02 1983-08-04 1984-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-02-02 1987-08-04 1988-02-03 $7700.00 Window Closed / Lapsed

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