Physical Sciences and Mathematics Commons^™

The Development Of An Arsenic(V) Selective Electrode, Sandra Gee Kang

Dissertations and Theses

The object of this research was to develop an arsenic(V) selective electrode. The electrode is based on a solid state membrane prepared by pressing a precipitate of silver arsenate-silver sulfide into a pellet. After the electrode was made, experiments were designed to check for three general characteristics of the electrodes: dependence of potential on pH for constant arsenic(V) concentration; dependence of potential on arsenic(V) concentrations at constant pH and extent of interference due to phosphate and arsenic(III) ions. From these measurements, it was found that Ag₂HAs0₄ was formed originally in the membranes containing a small fraction of …

Characterization Of Zinc-Containing Metalloproteins By Resonance Raman Spectroscopy, Robert Edward Derry

Dissertations and Theses

Cobalt-substituted carboxypeptidase and carbonic anhydrase were chosen as candidates for resonance Raman spectroscopy because they possess visible absorption due to the Co(II)-protein complex. However, no evidence for resonance-enhanced peaks due to the cobalt-containing chromophore was found with laser excitation near the visible absorption bands (514.5 nm) or closer to the ultraviolet absorption bands (457.9nm).

Arsanilazocarboxypeptidase and model azotyrosine compounds were selected for a Raman spectroscopic investigation because they have intense absorption bands in the visible region. All of these substances yielded similar resonance Raman spectra. Although there was no evidence for specific zinc-ligand vibrations, shifts in vibrational frequencies of the …

Alumina-Catalyzed Cope Rearrangement, Paul Jhy-Shing Wang

Dissertations and Theses

The alumina-catalyzed Cope rearrangements of meso- and dl-3,4-diphenylhexa-1,5-diene were examined in detail, following up a preliminary observation by H. Berg at Portland State University. Commercial column-chromatography grade alumina was employed, and was further activated before use by heating at 650-700° for four hours.

Using a ratio of 20 mg of dl-3,4-diphenylhex-l,5-diene to 1 g of alumina in heptane, the Cope rearrangement was complete within 15 minutes at room temperature to give exclusively trans,trans-1,6-diphenylhexa-1,5-diene. This was identified.by melting point, infrared spectroscopy and vapor phase chromatography.

The catalyzed rearrangement of meso-3,4-diphenylhexa-l,5-diene was run using the same diene …

A Phytochemical Investigation Of Liverwort Frullania Franciscana Howe, Timothy Ta-E Huang

Dissertations and Theses

Liverwort Frullania franciscana Howe was found high on the allergic test scale by J. Mitchell of the Medical School of the University of British Columbia and co-workers. Frullanolide was isolated from Frullania tamarisci by J.D. Connoly and by G. Oisson and his co-workers.

The plant sample, collected in Oregon, was hand separated, confirmed, air dried and milled before the extractions were done. A Soxhlet extraction with ether and cold extractions with n-hexane and with ether were carried out. Ether is a better extraction solvent than n-hexane for cold extraction.

Column chromatography was used for the separation of the extract based …