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K.A. McGee

Publications and source records attributed to K.A. McGee.

25 records · Page 2Linked to original sources
USGS1980

Annotated bibliography of spectrophotometric studies in the system U-Fe-Se-S-O-H, 1967-78

Preparation of this bibliography was originally begun to supply background information on previous ultraviolet and visible spectrophotometric studies on various chemical species thought to be important in the formation of sedimentary uranium deposits; we also thought that preparing the bibliography would help direct experimental efforts to determine the association of iron and uranium with several metastable sulfur species. In compiling these references, however, we found that much work had been done on the chemical species of interest by using types of spectroscopy other than ultraviolet and visible spectrophotometry. The dimensions of the bibliography were therefore broadened to include a wide variety of spectral-measuring techniques to make this report useful to a larger audience.

Open-File Report↗
USGS1977

A thermostatic water bath for experimental studies in aqueous solutions

A temperature-controlled water bath for the study of ion-pairing equilibria and mineral solubility in aqueous solutions below 100°C is described. The bath is similar to a previously described system (P. B. Hostetler and C. L. Christ, 1968, U.S. Geol. Survey Prof. Paper 600-D, p. D217-D221) but incorporates several significant improvements. Included among these are a more efficient stirring mechanism, a potentially larger solid-to-solution ratio, and improved equilibration of the gas phase with the solution.

Journal of Research of the U.S. Geological Survey↗
USGS1977

Activity-product constants of brucite from 10 degrees to 90 degrees C

The activity-product constant of brucite, K B = [Mg 2+ ][OH - ] 2 (where the brackets denote activities), was determined experimentally at 10°, 25°, 40°, 55°, 70°, and 90°C. The values obtained for -log K B are 10.89±0.16 (10°), 10.88±0.10 (25°), 10.90±0.10 (40°), 10.90±0.10 (55°), 10.99±0.14 (70°), and 11.10±0.14 (90°). Using National Bureau of Standards Technical Note 270 data for the ions, the free energy of formation (Δ G ° t ) at 25° for brucite is 831.486 joules per mole ( 198,730 cal mol -1 ). Using data compiled by R. A. Robie and D. R. Waldbaum in 1968 for the ions, this Δ G ° t is -823,323 J mol -1 (-198,930 cal mol -1 ). Values of log KB are also calculated for the temperature range 0° to 200°C, by using thermochemical data listed by V. B. Parker, D. D. Wagman, and W. H. Evans in 1971 and E. G. King, M. J. Ferrante, and L. B. Pankratz in 1975 and the partial molal heat capacities estimated by C. M. Criss and J. W. Cobble in 1965. The experimental values are similar to the calculated values, especially at lower temperatures.

Journal of Research of the U.S. Geological Survey↗