US3707870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for automatic and continuous plotting of absorption-desorption isotherms employed for determining the microstructure of porous bodies
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1971-02-22
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Granted: 1973-01-02
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Expires: 1991-02-22
Abstract
Abstract The apparatus essentially comprises a variable-volume enclosure, a pressure transducer in communication with said enclosure, a vacuum line, at least one pipe for the admission of adsorbable gases or vapors, a pipe for the admission of non-adsorbable gases and a sample-holder. Said pipes and said sample-holder are also in communication with said enclosure but can be cut-off by means of cocks. An analog computer is connected electrically to the transducer and to the enclosure and a cartesian-coordinate plotter is connected to the computer to provide absorptiondesorption isotherms. The enclosure, the transducer, the analog computer and the sample-holder are maintained at constant temperature.
Inventors
- 👤 B Rasneur
- 👤 M Herve
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:26
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/08; G01N15/088; G01N15/0893
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
127 words
An apparatus for plotting adsorption-desorption isotherms, wherein said apparatus essentially comprise a variable-volume enclosure, a pressure transducer in communication with said enclosure, at least three pipes including a vacuum line, at least one pipe for the admission of adsorbable gases or vapors and one pipe for the admission of non-adsorbable gases, a sample-holder containing the sample to which the measurements relate, said pipes and said sample-holder being also in communication with said enclosure but fitted with valves which serve to isolate them from said enclosure, an analog computer which is connected electrically to said transducer and to said enclosure and a cartesian coordinate plotter connected to said computer, constancy of temperature being ensured in the case of the enclosure, the transducer, the analog computer and the samPleholder.
Claim 2
Independent Claim
127 words
An apparatus for plotting adsorption-desorption isotherms, wherein said apparatus essentially comprise a variable-volume enclosure, a pressure transducer in communication with said enclosure, at least three pipes including a vacuum line, at least one pipe for the admission of adsorbable gases or vapors and one pipe for the admission of non-adsorbable gases, a sample-holder containing the sample to which the measurements relate, said pipes and said sample-holder being also in communication with said enclosure but fitted with valves which serve to isolate them from said enclosure, an analog computer which is connected electrically to said transducer and to said enclosure and a cartesian coordinate plotter connected to said computer, constancy of temperature being ensured in the case of the enclosure, the transducer, the analog computer and the samPleholder.
Claim 3
Dependent Claim
32 words
A plotting apparatus in accordance with claim 1, wherein the variable-volume enclosure is constituted by a calibrated buret which contains a column of mercury and communicates with a reserve supply of mercury.
Claim 4
Dependent Claim
39 words
A plotting apparatus in accordance with claim 2, wherein the level of the free surface of the mercury contained in the calibrated buret is determined by means of a homogenous platinum wire through which an electric current is passed.
Claim 5
Dependent Claim
24 words
An apparatus in accordance with claim 2, wherein the level of the free surface of mercury is determined by means of a spot follower.
Claim 6
Dependent Claim
39 words
An apparatus in accordance with claim 2, wherein the level of the free surface of the mercury is determined by means of a capacitance bridge whilst an external electrode and the column of mercury perform the function of capacitor.
Claim 7
Dependent Claim
36 words
A plotting apparatus in accordance with claim 1, wherein a programming unit is interposed between the analog computer and a drive unit which is controlled by said programming unit and modifies the volume of said enclosure.
Claim 8
Dependent Claim
15 words
A plotting apparatus in accordance with claim 6, wherein said programming unit comprises a capacitor.
References Cited (Backward Citations)
US3059478A
Cited
US3073149A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |