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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Fate of manure phosphorus in a weathered sandy clay loam soil amended with three animal manures

Van Averbeke, W, Azeez, JO 11 December 2009 (has links)
Laboratory incubation was conducted for 120 days to study the fate of phosphorus in poultry (PM), cattle (CM) and goat manures (GM). Phosphorus mineralized from manure was dependent on total P, Al and Fe content. Manures improved P availability in the order: PM > CM > GM; however, the highest amount of P was fixed or immobilized between 10 and 70 days of incubating with CM and GM. Fixation and immobilization of mineralized P from poultry manure was negligible probably due to the high total P and the low amount of Al and Fe. Generally, manure application reduced the ability of the soil to fix P. More than 90% of the manure P was either immobilized or fixed by the soil. The relationship between the amount of P released and time was cubic. Improvement of the C:P ratio of CM and GM would be an option to enhance their agronomic use as fertilizer P source.
102

Persistence of {221}-propeller phytase in soil and its implication in phosphorus mobilization

Leung, Miu-fun., 梁妙芬. January 2004 (has links)
published_or_final_version / abstract / toc / Zoology / Master / Master of Philosophy
103

Some platinum and rhodium complexes containing phosphorus ligands

雷鐵洛, Lui, Tit-lok, Eddie. January 1977 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
104

Evaluation of different laboratory indexes and plant measurements of phosphorus availability in Arizona soils

Holanda, Francisco José Martins, 1945- January 1972 (has links)
No description available.
105

The availability of phosphorus from various biological residues as a source of phosphorus for succeeding crops

Miller, Raymond W., 1928- January 1953 (has links)
No description available.
106

The utilization of phosphorus from different crop residues by rye grass

Nielsen, Donald R., 1931- January 1954 (has links)
No description available.
107

The solubility of white phosphorus in various organic solvents at different temperatures; with special reference to a further confirmation of the internal pressure theory of solubility

Mason, Charles Morgan January 1929 (has links)
No description available.
108

The synthesis of chiral organosul fur and phosphorus compounds /

Friedlander, Barry Terence. January 1980 (has links)
A general route to optically active organosulfur and phosphorus compounds was investigated. Sulfinimides incorporating camphorimide were synthesized directly from a sulfinyl chloride and N-(trimethylsilyl)camphorimide. The diastereomers were found to be inseparable by crystallization or chromatography, although in one case an optically active sulfinamide was prepared by an asymmetric synthesis. / The phosphorus-imide bond was formed by coupling of an asymmetric phosphinous chloride and N-(trimethylsilyl)camphorimide. Addition of sulfur gave N-(phosphinothioyl)camphorimides as separable diastereomers. These were converted into optically active thiophosphoryl compounds which were chiral only at phosphorus. The absolute configurations of the diastereomers were obtained by single-crystal X-ray analysis, through NMR techniques and by conversion into phosphinothioic acids. / Displacement of camphorimide was effected with organometallic reagents, alcohols and thiols to give optically active phosphine sulfides, phosphinothionates and phosphinodithioates respectively. Optical yields of the products were dependant on the reagents and reaction conditions used. Mechanistic rationales are presented to account for the stereochemical results.
109

Cationic and Dicationic Phosphine Complexes of Tin and Germanium

MacDonald, Elizabeth 09 August 2013 (has links)
This dissertation explores the synthesis and characterization of phosphine stabilized tetrel (group 14) cations. Tetrel cations are readily generated by reacting a halogermane or halostannane with a Lewis acid to generate an in situ germylium, stannylium cation or an in situ germyldiylium, stannyldiylium dication. A Lewis base such as a phosphine is added to the mixture to produce the corresponding salt with dative P-Sn or P-Ge connectivity. Tin and germanium salts represent new as well as unique cationic structures for phosphorus containing species. The preparation of these salts is proven to be generalizable, reproducible, and can be isolated as pure materials in moderate to high yields.
110

Quadrupole hyperfine structure in the microwave spectra of phosphorous trichloride and phosphoryl chloride

Nave, Carl Rodney 08 1900 (has links)
No description available.

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