Section II: Chemistry.
Georgia Journal of Science 2010, Spring, 68, 1
Georgia Journal of Science
Dit boek is als download beschikbaar op je Mac of iOS-apparaat met iBooks, en op je computer met iTunes. Boeken kunnen worden gelezen met iBooks op je Mac of iOS-apparaat.
8:00 A COMPARISON OF THE N-TERMINAL MANGANESE BINDING SITE OF OXALATE DECARBOXYLASE (PDB CODE: 1UW8) WITH A MINIMIZED STRUCTURE OF THE SAME ATOMS **, Crystal Bruce * and Ellen W. Moomaw, Gainesville State College, Oakwood, GA 30566. Oxalate decarboxylase (OxDC) catalyzes the difficult carbon-carbon bond cleavage of oxalate to yield carbon dioxide and formate. High resolution X-ray crystal structures of Bacillus subtilis OxDC (PDB codes: 1J58 and 1UW8) have confirmed that the OxDC monomer is composed of two [beta]-barrel domains, each of which contains a Mn-binding site. These Mn ions are 26 angstroms apart from each other in the monomer. In the current work we are using the tools of molecular modeling (Deep View--Swiss pdb Viewer and Spartan 08) to compare the constrained structure of the N-terminal domain manganese-binding site of oxalate decarboxylase (PDB code: 1uw8) with the ideal (minimized) structure. We are comparing bond angles and atom distances in the minimized structure and that from the crystal structure to understand the degree of constraint in the available crystallographic snapshot. 8:20 SYNTHESIS AND THERMAL ANALYSIS OF NEW PHOSPHONATED NORBORNENE HOMO- AND COPOLYMERS, ** Sergey A. Isarov *, Michelle J. Razumov *, Jacob L. Hicks * and Gregory J. Gabriel, Kennesaw State University, Kennesaw, GA 30144. Phosphorous-containing macromolecules have many applications including bioadhesives, fuel cell membranes, and fire-retardant (FR) materials. A series of new phosphonate-containing norbornene homopolymers and statistically random copolymers were polymerized in 5 minutes at room temperature via ROMP. Gel permeation chromatography (GPC) measured polydispersities of less than 1.15 for all polymers. NMR spectroscopy indicated that targeted chain lengths and percent phosphonate compositions were achieved. In this talk we will discuss our interest and studies in using these polymers as FR additives. A total of 15 polymers were studied by thermogravimetric analysis (TGA). TGA showed a well-defined, three-stage degradation process distinct from other polymeric phosphorus FR analogues reported in literature. Notably, we observed that onset temperature and char yield were easily tunable by varying the chain length and percent phosphonate content. These trends may help in the design and development of more inexpensive and compatible FR additives for wider use in materials from clothing to wire coatings to construction materials.
- € 2,99
- Categorie: Techniek
- Publicatiedatum: 22-03-2010
- Uitgever: Georgia Academy of Science
- Tekstlengte: 10 pagina's
- Taal: Engels