Thesis (Ph. M.)--University of Wisconsin--Madison, 1937. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 33-36).

Thesis--Copenhagen. / Literaturfortegnelse: p. [186]-191.

Thesis (M.S.) in Food Science and Human Nutrition--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 46-51).

The ligand binding properties of the Fe(III) Porphyrin microperoxidase-8 (MP-8) and several Co(III) Corrinoids towards nitrogenous bases have been studied. More than 70 equilibrium constants for axial ligand substitution of three series of nitrogenous bases (Amines, Pyridines, Imidazole and their derivatives) with Fe(III)MP-8 and five different corrinoid complexes varying in the trans ligand X (X = Methyl, Vinyl, CN, Bzm and H2O) have been determined spectrophotometrically in aqueous solution. A base line verifying the general equation log K =a.pK +b has been established for each metal complex with these nitrogenous bases, when the pK is the only significant variable, the value of (a) is comparable but values of (b) fall in the order 5-heterocycles > 6-heterocycles > amines. These base lines are characterised by the wide range of pK's (pK =5.3 -10.6 for primary amines, 0.4- 9.76 for 6- membered heterocyclic compounds and 2.3 - 14.3 for 5-membered heterocyclic compounds). The most striking base line was found in the case of the 5-membered heterocyclic compounds which covered 12 pK units, including imidazole, 1,2,4-triazole, their conjugated anions, together with certain substituted imidazoles. These base lines include the first linear basicity correlations for any Fe Porphyrin or for 5- heterocycles with any transition metal ion. The value of the slope (a) increased linearly with published data on the trans effect and furthermore the established base lines pass through a focal point which is different for each family in the range pK =-2 to 0, log K =-2 to 0. These base lines showed the enhancement of log K in the case of hydroxyl amine, hydrazine and pyridazine above the established base lines, this was ascribed to the so called a-effect for the first time in metal-ligand bonding. Also, the base lines help to quantify the suppression in log K value due to the steric hindrance as in the case of a and p-branching of amines and also the two substituted pyridines. A new mechanistic pathway was established for the methylation of Co(II) with methyl iodide in presence of the thiol (RSH) complex of Co(II). This reaction showed that increasing the electron density on the Co(II) ion by coordination of the polarisable RSH ligand induced some of the reactivity towards Mel characteristic of the fully reduced Co(I) corrinoids.

The purpose of this study was to compare the distribution of dinoflagellates in the Strait of Georgia, British Columbia with a number of environmental parameters, and in particular with vitamin B₁₂ concentrations. The latter was determined by a modified bioassay technique, employing the marine dinoflagellate, Amphidinium carterae Hulburt. The conclusions are based on the analysis of 511 samples from 19 cruises. The annual cycle of vitamin B₁₂ found to be characterized by three major peaks of concentration: 1) a peak following the spring 'bloom' of phytoplankton; 2) a summer increase that was closely associated with silt particles contained in river runoff; and 3) a fall maximum that followed the breakdown of density gradients in the water column. Seventy-seven species of dinoflagellates were recorded from the Strait of Georgia. The temporal distribution of dinoflagellates was divided into two distinct periods of abundance: one occurring during the early spring months and another during the summer months. The results of multiple regression analyses between the dinoflagellates and the environmental parameters measured (vitamin B₁₂, nitrogen, phosphorus, zooplankton, temperature, salinity and sunlight) indicated that the size of the dinoflagellate community in the early spring was closely associated with vitamin B₁₂ concentration in the water column. Nitrogen concentration was apparently a significant factor in determining the size of the community during the late summer months. Phosphorus concentration did not appear to be closely related with total dinoflagellate numbers. The composition and seasonal distribution of the dinoflagellates was found to be essentially similar to that of other northern temperate neritic waters. The major exception was the presence of a distinct spring component in the Strait of Georgia, consisting largely of small nonthecate species. / Science, Faculty of / Botany, Department of / Graduate

May E. Winfield / Typescript / M.S. Florida State College for Women 1926 / Includes bibliographical references

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