Spelling suggestions: "subject:"anitrogen"" "subject:"initrogen""
691 |
Diversity of rhizobia nodulating the tree legumes Acacia mangium and Paraserianthes falcataria and their interaction with arbuscular mycorrhizal fungi in young seedlingsMansur, Irdika January 2000 (has links)
No description available.
|
692 |
Adsorption of selected herbicides from water using activated carbon and polymeric adsorbentsHorner, Daniel J. January 1999 (has links)
A range of adsorbents have been evaluated for the adsorption of selected herbicide compounds from aqueous solution. The adsorption performance of LF -1, a carbonised polymer produced in the laboratory, Amberlite XAD-4, a commercially available polymeric adsorbent produced by Rohm and Haas and MN-200, a HypersolMacronet polymer produced by Purolite, were compared with a commercial activated carbon, Chemviron F -400. The pore size distributions of the adsorbents have been investigated using nitrogen adsorption. F-400, LF-1 and MN-200 were found to contain similar microporous structures. The carbons also possess a significant degree of mesoporous structure, which may enhance the diffusion of organic species into the micropores. The pore size distribution for XAD-4 shows an almost exclusive meso/macroporosity with very little microporous structure. Spectroscopic analysis and titration of the adsorbents indicated a number of different oxygen functional groups. XPS and elemental analysis suggested higher oxygen concentrations than those obtained using direct titration, which was attributed to bound oxygen within the structure of the adsorbents. The adsorption capacity of phenol was assessed as a characterisation technique. The capacity of the carbons was much greater than the polymeric adsorbents. Analytical techniques were developed and validated for the determination of trace levels (0.1 parts per billion) of five herbicides; atrazine, benazolin, bentazone, imazapyr and tric1opyr. Single and multi-component adsorption isotherms are presented for trace concentrations of the herbicides in aqueous solution. The effect of pH and fulvic acid upon the adsorption was also investigated. Mini-column experiments were performed using multi-component mixtures. In all cases, the uptake of herbicides on F -400 is greater than on the other adsorbents. Regeneration of F-400 and MN-200 was investigated usmg solvent stripping techniques. Significant regeneration efficiencies were observed using ethanol at pH 12 and 50°C to make the technique a viable option.
|
693 |
Molecular analyses of symbiotic and defense-related responses in white clover rootsCrockard, Martin A. January 1999 (has links)
No description available.
|
694 |
Effects of light intensity and nitrogen on growth of corn and grass-legume mixture.Chan, Wing-To. January 1969 (has links)
No description available.
|
695 |
Effects of delayed transplanting and nitrogen fertilization of lettuce on a pealettuce intercropBailleul, Stéphane M. (Stéphane Marc) January 1993 (has links)
Intercropping of a short-cycle legume crop and a longer-cycle non-legume crop has been suggested as a potentially beneficial intercrop combination. Most studies have concerned cereal and legume corps. Few have involved horticultural crops. In 1990 and 1991, a 56-day semi-leafless pea crop (Curly) and a 75-day lettuce crop (Paris Island Cos) were grown both as monocrops and as intercrops. Intercrops consisting of alternating rows of each crop, represented additive populations (56:100) of peas and lettuce. Three lettuce transplanting dates (June 19, 25 and July 4) and three nitrogen fertilizer rates (0, 50, 100 kg ha$ sp{-1}$) were tested. Peas were all sown on May 18. In addition, a new pea/lettuce intercropping pattern (45:82), consisting of alternating double rows of peas and lettuce, was tested in 1991. The $ sp{15}$N dilution method was also used to test for nitrogen transfer. Alternate row intercropped lettuce plant$ sp{-1}$ yields were, on average, 76% and 46% lower than their corresponding monocrop yields for the early and late transplanted lettuce, respectively. Declines in yield of 63% and 55% were reported for the double row intercropped lettuce for the early and late transplanting dates, respectively. Nitrogen fertilization significantly improved intercropped fresh lettuce yields but had no effect on monocropped lettuce. Pea yields m$ sp{-1}$ row were unaffected by intercropping. Alternate row land equivalent ratios (LER) ranged from 0.87 to 1.05 and from 1.06 to 1.63, in 1990 and 1991, respectively. The double row LER's ranged from 1.06 to 1.21 in 1991. The higher LER's in 1991 reflected higher pea yields. No evidence of nitrogen transfer to the lettuce crop was detected.
|
696 |
Nitrogen movement and losses from application of animal wastes to soils.Iqbal, Muhammad Mohsin. January 1972 (has links)
No description available.
|
697 |
Field, greenhouse and laboratory studies of transformation and translocation of 15N-labelled fertilizer in a boreal forest black spruce (Picca mariana) system.Lefebvre, Jacques Luc. January 1972 (has links)
No description available.
|
698 |
Modeling ecological determinants of the symbiotic performance of introduced rhizobia in tropical soilsThies, Janice E January 1990 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references (leaves 164-173) / Microfiche. / xi, 173 leaves, bound ill. 29 cm
|
699 |
Immobilization and mineralization of nitrogen in Hawaiian soilsAgarwal, Anand Swaroop January 1967 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1967. / Bibliography: leaves 124-137. / xiv, 159 l graphs, tables
|
700 |
Studies on nitrogen transformation and nitrate adsorption in soils / Nitrogen transformation and nitrate adsorption in soilsSingh, Budh Ram January 1968 (has links)
Typescript. / Bibliography: leaves [97]-105. / xiii, 105 l graphs, tables
|
Page generated in 0.0373 seconds