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Full-Text Articles in Physical Sciences and Mathematics

Inhibition Of Total Gas And Methane Production In Anaerobic Digestion By Various Toxicants, Steven H. Malehorn Jan 1993

Inhibition Of Total Gas And Methane Production In Anaerobic Digestion By Various Toxicants, Steven H. Malehorn

Masters Theses

Heavy metal inhibition of anaerobic digestion of municipal sewage sludge has been investigated over the past 50 years. Many assays began with steady-state conditions and observed the rate at which total gas or methane production decreased due to toxicant inhibition. These methods required considerable time and labor. Modified Warburg respirometers and serum bottle assays reduced much of the effort, but each method has limitations in terms of complexity, cost, and accuracy.

This series of experiments had two objectives: 1) develop a quick, inexpensive, and easy method to measure methanogenic activity in anaerobic digesters, and 2) determine median inhibitory concentrations (IC …


Synthesis And Characterization Of Transition Metal Polypyridyl Complexes With A Novel 1,10-Phenanthropteridinedione Ligand, Huakai Huang Jan 1993

Synthesis And Characterization Of Transition Metal Polypyridyl Complexes With A Novel 1,10-Phenanthropteridinedione Ligand, Huakai Huang

Masters Theses

A new alloxazine ligand (1; "Pptd"), produced by the condensation of 1,10-phenanthroline-5,6-dione with 5,6-diamino-1,3-dimethyluracil, and several transition metal complexes containing this ligand, have been synthesized. The Pptd ligands attach to Ru(II), Co(II), or Re(I) metal centers through the phenanthroline linkage to form stable polypyridyl complexes. The spectral and the electrochemical characterization of Pptd complexes of Ru(II), Co(II), and Re(I) is presented.

Pptd is capable of being reduced (across the pyrazine nitrogens) by two H-atoms. When coordinated to Ru(II), Pptd forms stable complexes which retain the robust characteristics and electrochemical activity of other Ru(II) polypyridyl species. In addition, Ru(II) complexes of …


Vegetation And Tree Survival In A Savanna Restoration Project, Vermilion County, Illinois, Mary Claire Hruska Jan 1993

Vegetation And Tree Survival In A Savanna Restoration Project, Vermilion County, Illinois, Mary Claire Hruska

Masters Theses

This study involved pre-burn and post-burn inventories of herbaceous and woody vegetation, a post-burn tree survival survey, the development and implementation of a management plan for the savanna restoration site and the development of general guidelines for savanna restoration. An herbarium collection was made, 242 species representing 64 families were found on the site.

There were several significant changes in the density and frequency of vegetation after the burn. The following herbaceous species increased significantly in frequency: Agalinis tenuifolia (Vahl.) Raf, Ambrosia artemisiifolia L., Carex spp., Cassia fasciculata Michx., Desmodium glabellum (Michx.) DC., Dichanthelium acuminatum (Sw.) Gould & Clark var. …