US4509855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual liquid and gas chromatograph system
Assignee: United States, ENERGY THE, Department of
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Filing: 1983-02-08
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Granted: 1985-04-09
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Expires: 2003-02-08
Abstract
Abstract A chromatographic system that utilizes one detection system for gas chromatographic and micro-liquid chromatographic determinations. The detection system is a direct-current, atmospheric-pressure, helium plasma emission spectrometer. The detector utilizes a non-transparent plasma source unit which contains the plasma region and two side-arms which receive effluents from the micro-liquid chromatograph and the gas chromatograph. The dual nature of this chromatographic system offers: (1) extreme flexibility in the samples to be examined; (2) extremely low sensitivity; (3) element selectivity; (4) long-term stability; (5) direct correlation of data from the liquid and gas samples; (6) simpler operation than with individual liquid and gas chromatographs, each with different detection systems; and (7) cheaper than a commercial liquid chromatograph and a gas chromatograph.
Inventors
- 👤 Don D. Gay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:20
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/62; G01N21/71; G01N21/73; G01N30/00; G01N30/02; G01N30/62; G01N30/74
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
98 words
A dual mode direct current plasma spectrometer which comprises, in combination: (a) a plasma source unit including (i) a plasma source, (ii) eluant and gas inlet means, (iii) a plasma sustaining region, and (iv) a plasma viewing means in said region connected to said spectrometer; (b) a micro-column liquid chromatograph connected to said eluant inlet means; (c) a gas chromatograph connected to said gas inlet means; and (d) heater means attached to said plasma source unit, said heater means being adapted to control the temperature of said plasma and the vapor phase from said chromatographs (b) and (c).
Claim 2
Dependent Claim
98 words
A dual mode direct current plasma spectrometer which comprises, in combination: (a) a plasma source unit including (i) a plasma source, (ii) eluant and gas inlet means, (iii) a plasma sustaining region, and (iv) a plasma viewing means in said region connected to said spectrometer; (b) a micro-column liquid chromatograph connected to said eluant inlet means; (c) a gas chromatograph connected to said gas inlet means; and (d) heater means attached to said plasma source unit, said heater means being adapted to control the temperature of said plasma and the vapor phase from said chromatographs (b) and (c).
Claim 3
Dependent Claim
17 words
The improvement as claimed in claim 1 wherein said plasma source is plasma-forming gas which is helium.
Claim 4
Dependent Claim
20 words
The improvement as claimed in claim 1 wherein the plasma viewing means is an opening in said plasma source unit.
Claim 5
Dependent Claim
18 words
The improvement as claimed in claim 3 wherein said opening is between about 1 and 2 mm diameter.
Claim 6
Dependent Claim
76 words
In a direct current plasma emission spectrometer, which includes a plasma source unit and micro-column liquid chromatograph, the improvement which comprises: (a) gas inlet means disposed in said plasma source unit; (b) gas chromatograph means connected to said plasma source unit through said gas inlet means; and (c) heater means attached to said plasma source unit, said heater means being adapted to control the temperature of the plasma and the vapor phase from said gas chromatograph.
Claim 7
Dependent Claim
76 words
In a direct current plasma emission spectrometer, which includes a plasma source unit and micro-column liquid chromatograph, the improvement which comprises: (a) gas inlet means disposed in said plasma source unit; (b) gas chromatograph means connected to said plasma source unit through said gas inlet means; and (c) heater means attached to said plasma source unit, said heater means being adapted to control the temperature of the plasma and the vapor phase from said gas chromatograph.
Claim 8
Dependent Claim
23 words
The improvement as claimed in claim 5 wherein said spectrometer is operable in a liquid chromatograph mode or in a gas chromatograph mode.
Claim 9
Dependent Claim
111 words
In a direct current plasma emission spectrometer, which includes a plasma source unit having a carrier gas therein and a source of electrical potential to sustain a plasma, and a micro-column liquid chromatograph connected to an inlet of said plasma source unit, the improvement which comprises: (a) a gas inlet means disposed in fixed spaced relation to said liquid chromatograph inlet; (b) a gas chromatograph means connected to said plasma source unit through said gas inlet; and (c) a heater means surrounding the inlets of said plasma source unit, said heater means being adapted to control the temperature of said plasma and the vapor phase from said chromatographs (b) and (c).
Claim 10
Dependent Claim
111 words
In a direct current plasma emission spectrometer, which includes a plasma source unit having a carrier gas therein and a source of electrical potential to sustain a plasma, and a micro-column liquid chromatograph connected to an inlet of said plasma source unit, the improvement which comprises: (a) a gas inlet means disposed in fixed spaced relation to said liquid chromatograph inlet; (b) a gas chromatograph means connected to said plasma source unit through said gas inlet; and (c) a heater means surrounding the inlets of said plasma source unit, said heater means being adapted to control the temperature of said plasma and the vapor phase from said chromatographs (b) and (c).
Claim 11
Dependent Claim
23 words
The improvement as claimed in claim 7 wherein said spectrometer is operable in a liquid chromatogaph mode or in a gas chromatograph mode.
References Cited (Backward Citations)
US3612686A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-08 | 1988-10-08 | 1989-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-08 | 1992-10-08 | 1993-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-08 | 1996-10-08 | 1997-04-09 | $7700.00 | Window Closed / Lapsed |