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Showing 1 to 20 of 176 for “"Nitrogen Fixation"”.
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Studies on biological nitrogen fixation.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 1991
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Mechanistic models of oceanic nitrogen fixation
Oceanic nitrogen fixation and biogeochemical interactions between the nitrogen, phosphorus and iron cycles have important implications for the control of primary production and carbon storage in the ocean. The biological process of nitrogen fixation is thought to be particularly important where the …
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Nitrogen Fixation By Azotobacter Species In Mixed Culture
… that ammonia, the natural endproduct of nitrogen fixation, acts as a corepressor of nitrogenase synthesis. It has also been shown that ammonia will accumulate in the medium of pure cultures of Azotobacter vinelandii until levels become high enough to repress nitrogenase synthesis. A. …
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Effects of light and temperature on nitrogen-fixation rates in arable soils and seasonal fluctuations in nitrogen-fixation rates in arable soils
Nitrogen-fixation rates were determined by C₂H₂ reduction in intact cores taken from the top 0-1 cm of two soils. The cores were moistened and incubated under varying light (0-88 W•m⁻²) and temperature (7.5- 39.5ºC) conditions at four different times of the year to determine the effects of day …
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Soybean nitrogen dynamics: Nitrogen fixation, yield, and residue decomposition
<p>Nitrogen (N) a crucial element for plant growth, often limits net primary productivity of agroecosystems. In agricultural systems it is vital to have proper management of N to secure productivity and environmental sustainability. Soybean [Glycine max (L.) Merr.] is the second most important crop …
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The relationship between iron and nitrogen fixation in Trichodesmium spp.
Trichodesmium spp. are considered the dominant nitrogen (N) fixing cyanobacteria in tropical and subtropical oceans, regimes frequently characterized by low iron (Fe). Limited information exists about what levels of Fe limit Trichodesmium N fixation. I developed a diagnostic for Fe limitation using …
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Oxygen control of nitrogen fixation in Frankia and Coriaria arborea
Oxygen has a central role in regulation of nitrogen fixation activity in both asymbiotic Frankia and Frankia - actinorhizal plant symbioses. Daily addition of fresh medium at a low dilution rate (D=0.125 day⁻¹) allowed Frankia to be maintained in continuous culture with a stable rate of growth and …
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Soybean Maturity Group Tradeoffs: Irrigation, Weed Control, and Nitrogen Fixation
… covering weed control, irrigation needs and nitrogen fixation amounts across soybean maturity group. Chapter II will go into further detail outlining the first applied experiment dealing with weed control and irrigation issues. Alternative weed control methods are analyzed in conjunction with …
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The relationship between iron and nitrogen fixation in Trichodesmium spp.
Trichodesmium spp. are considered the dominant nitrogen (N) fixing cyanobacteria in tropical and subtropical oceans, regimes frequently characterized by low iron (Fe). Limited information exists about what levels of Fe limit Trichodesmium N fixation. I developed a diagnostic for Fe limitation using …
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Actinorhizal Plant Nodulation and Nitrogen Fixation in Natural and Experimental Systems
In a separate study, water-retentive polymer carriers of Frankia inoculum were applied as a root dip to Alnus glutinosa and Casuarina equisetifoloia seedlings. This treatment increased nodulation 5- to 10-fold in greenhouse experiments and also of A. glutinosa in a field experiment.
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Evaluation of African trifolium species for growth and biological nitrogen fixation
… were evaluated for growth and biological nitrogen fixation (BNF) in a greenhouse on both soils with limited, adequate, and excessive soil moisture. Rhizobia were also evaluated for survival in desiccated soil (12.5 and 17.5 g H₂O g⁻¹ soil) and for competitive nodule forming ability. …
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Sustainable atmospheric ammonia synthesis and nitrogen fixation using non-thermal plasma (NTP)
… was found that this approach could produce other nitrogen compounds (nitrate and nitrite acids) while generating ammonium, which could potentially add value to the products of the plasma-assisted ammonia synthesis process. Based on the results, the challenges and future opportunities of the …
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Biological nitrogen fixation in a nitrogen limited tropical lake, Lake Chapala, Mexico.
… my study was to quantify the rate of biological nitrogen fixation in Lake Chapala, Mexico. Lake Chapala is the largest lake in Mexico. It is an ancient, tropical lake which is shaped in an east-west culde-sac with the inflow and outflow at the eastern end. Previous work showed low available …
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Characteristics of Intercropped Sorghum and Soybeans; And Soybean Nitrogen-Fixation Under Shade
Made available in DSpace on 2014-12-14T14:37:20Z (GMT). No. of bitstreams: 1 7709232.pdf: 4816470 bytes, checksum: 616bebea0695b79b6b66ef1b709a3aa5 (MD5) Previous issue date: 1976
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Nitrogen fixation potential and agronomic evaluation of three hypernodulating mutants of soybean
… for short-term NO$\sb3\sp-$ effect on N$\sb2$ fixation, measured by an acetylene (C$\sb2$H$\sb2$) reduction assay and by the relative ureide abundance technique. Nitrate was supplied to 3-week-old, hydroponically grown plants with fully developed nodules. Application of 5 mM NO$\sb3\sp-$ …
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