US4921803A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Immobilized blue-green algae
Assignee: Kimberly Clark Worldwide Inc
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Filing: 1987-03-17
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Granted: 1990-05-01
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Expires: 2007-03-17
Abstract
Abstract A composite is prepared which includes a substantially water-insoluble particulate or fibrous support having a surface energy of at least about 19 dynes per cm to which nitrogen-fixing filamentous heterocystous blue-green algae are attached. The support does not have a deleterious effect on the viability of the attached algae, and is preferably polypropylene or cellulosic. Preparing the composite includes contacting the support with blue-green algae to permit the algae to attach to the support by means of heterocyst cells. The attached cells in a nitrogen-deficient environment, fix nitrogen at a rate substantially greater than unattached cells, and have agricultural applications.
Inventors
- 👤 Ronald S. Nohr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:07
CPC Classifications
C; C12; C12N; C12N11/00; C12N11/02; C12N11/10; C12N11/12; C05; C05C; C05C11/00; C05F; C05F11/00; C05F11/08; C12N1/00; C12N1/12; C12N11/08; C12N11/082
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
A composite which comprises a substantially water-insoluble support having a surface energy of from about 30 dynes per cm to about 115 dynes per cm to which nitrogen-fixing filamentous blue-green algal heterocyst cells are attached, said support being polypropylene or a cellulosic which is particulate or fibrous and which is substantially free of substances which have a significant deleterious effect on the viability of the attached algae, which attached algal heterocyst cells, when allowed to grow in nitrogen-deficient environment, fix nitrogen at a rate which is substantially greater than that of such cells not so attached.
Claim 2
Dependent Claim
96 words
A composite which comprises a substantially water-insoluble support having a surface energy of from about 30 dynes per cm to about 115 dynes per cm to which nitrogen-fixing filamentous blue-green algal heterocyst cells are attached, said support being polypropylene or a cellulosic which is particulate or fibrous and which is substantially free of substances which have a significant deleterious effect on the viability of the attached algae, which attached algal heterocyst cells, when allowed to grow in nitrogen-deficient environment, fix nitrogen at a rate which is substantially greater than that of such cells not so attached.
Claim 3
Dependent Claim
12 words
The composite of claim 1, in which said polypropylene support is meltblown.
Claim 4
Dependent Claim
14 words
The composite of claim 1, in which said cellulosic support comprises thermomechanical wood pulp.
Claim 5
Dependent Claim
15 words
The composite of claim 1, in which said cellulosic support is debonded chemical wood pulp.
Claim 6
Dependent Claim
9 words
The composite of claim 1 in admixture with water.
Claim 7
Dependent Claim
9 words
The composite of claim 3 in admixture with water.
Claim 8
Dependent Claim
9 words
The composite of claim 4 in admixture with water.
References Cited (Backward Citations)
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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) | 1993-04-30 | 1993-10-30 | 1994-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-30 | 1997-10-30 | 1998-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-30 | 2001-10-30 | 2002-05-01 | $7700.00 | Window Closed / Lapsed |