Patent US2472254A successfully refreshed from Google Patents.
US2472254A
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Apparatus and method for carrying out catalytic reactions
Assignee: Shell Development Co
•
Filing: 1944-08-22
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Granted: 1949-06-07
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Expires: 1964-08-22
Abstract
No abstract record available.
Inventors
- 👤 Ava J Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:42
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/42; C07C5/54; C07C5/50; C07C5/52; Y; Y10; Y10S; Y10S585/00; Y10S585/8995; Y10S585/906; Y10S585/909; Y10S585/911
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1386760A
Cited
US1991353A
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US2127561A
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US2161247A
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US2167339A
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US2238851A
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US2263363A
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US2284468A
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GB543838A
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US2328756A
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US2302328A
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US2337684A
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US2290211A
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US2378342A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-06-06 | 1952-12-06 | 1953-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-06-06 | 1956-12-06 | 1957-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-06-06 | 1960-12-06 | 1961-06-07 | $7700.00 | Window Closed / Lapsed |