West Valley Nuclear Services Research Articles

Study of Creatinine and its 5-Alkoxy Analogs: Structure and Conformational Studies in the Solid and Solution States by X-Ray Crystallography, NMR, UV and Mass Spectrometry

Creatinine (2-amino-1,5- dihydro-1-methyl-4-imidazolone) is a natural by-product of cellular metabolism related to muscular mass. It is excreted in human urine and is necessary for normal kidney function. Urinary secretion of creatinine serves as a bench mark for several clinical measurements. Recently, in our laboratories, during the course of an investigation of the urine of cancer patients for tumor markers, we found some new metabolites of creatinine. These were identified as 5-methoxy and 5-ethoxy creatinine by UV, NMR and Mass spectrometry and their tautomeric structures confirmed by crystal structural investigations of the metabolites. The x-ray crystallographic analysis confirmed the structures of the compound and showed that it exists in the 2-amino form. The spectral characteristics of these new compounds and the generality of the reaction are discussed in this paper. Creatinine, when allowed to react with methanol, ethanol and propanol respectively, in the presence of charcoal and air gave the 5-methoxy, 5-ethoxy and 5-propoxy creatinine derivatives respectively, suggesting a generality of a reaction. The reaction of creatinine with alcohols in the presence of charcoal and air takes place through a free radical reaction mechanism. ‡ Present Address: Analytical and Process Chemistry, MS-301, West Valley Nuclear Services Co., Inc., P.O. Box 191, West Valley, New York 14171-0191. ** Deceased

Correlation Between Composition Effects on Glass Durability and the Structural Role of the Constituent Oxides

In this article the effects on durability of composition variations in West Valley Nuclear Services Company preliminary waste glass composition WV205 are discussed. MCC-3 results at times from 7 to 180 days are presented for 50 glass compositions. The results are suggestive of a large plateau region where durability is good and weakly dependent on composition, adjoining a region in which durability is a much steeper function of composition. The same effect is observed when the redox state of the iron, which comprises --12wt% of the glass, is varied. The general trends are discussed in terms of the structural roles of the components. The effects of the alkalies and alkaline earths correlate quite well with the field strengths of these ions.

A statistical approach for characterizing chemical durability within a waste glass compositional region

In order to qualify nuclear waste forms for disposal in geological repositories, waste glass producers must adequately describe the properties of the glass. One of the most important of these properties is chemical durability (resistance to leaching). An approach for characterizing the chemical durability of a producer's waste glass form must take into account that the composition of the glass will vary during production. Thus, leach testing performed as part of the characterization effort must investigate the range of glasses that are likely to be produced. Also, the approach must account for the fact that only a limited number of compositional variations can be tested and that the leach test results will be subject to uncertainty. A statistical approach that satisfies these goals is presented. The statistical approach for characterizing the chemical durability of waste glasses in a specified compositional region involves the following steps: defining the compositional region of anticipated production glass, selecting a test matrix of compositions via computer-aided experimental design techniques, leach testing, empirical modeling of the leach test results, investigating glass component effects, and using statistical confidence statements to describe chemical durability over the compositional region. These steps are illustrated using the results of work performed at Pacific Northwest Laboratory for West Valley Nuclear Services.