Physical Sciences and Mathematics Commons^™

A Thermodynamic Study Of Step-Wise Complex Formation In Several Aqueous Copper (Ii)-Amino Acid Systems, Vipin M. Kothari

Theses and Dissertations

pK_n values for step-wise dissociation of protons from the protonated ligands (glycine, α-amino isobutyric acid, sarcosine and theonine) were determined potentiometrically with a Beckman Model GS pH meter in aqueous solution at 10, 20, 30 and 40° C. Log K values for step-wise interaction of glycine, α-amino isobutyric acid, sarcosine and threonine with copper(II) ion were also determined potentiometrically with a pH meter at 10, 20, 30 and 40° C. The standard free energy of formation for the step-wise interaction of copper(II) with each of the above ligands was calculated from the values of log K. Enthalpy and entropy changes …

A Thermodynamic Study Of Complex Formation In Aqueous Solution.|Ni.|Pthe Hg(Ii)-, Zn(Ii)-, Cd(Ii)-, Ag(I)-Serine Systems.|Nii.|Pthe Hg(Ii)-, Zn(Ii)-, Cd(Ii)-, In(Iii)- Thioglycollic Acid System :|Ba Study Of The Effect Of D[Pi]-D[Pi] Bonding On These Complexes, Marriner Lee Morrell

Theses and Dissertations

Thermodynamic equilibrium constants were obtained potentiometrically using a Beckman pH meter for metal-serine and metal-thioglycolloc acid complexes to study the thermodynamic properties of the complexes and the effect of dπ - dπ bonding on the equilibrium constants. The following calculations were made: 1. The stepwise dissociation of protons from serine at 10, 20, 30, and 40°C and the stepwise dissociation of protons from thioglycollic acid at 20, 30, and 40°C. 2. The thermodynamic formation constants for Zn(II), Cd(II), Hg(II), and Ag(I) with serine at 10, 20, 30, and 40°C and at two ionic strengths. 3. The thermodynamic formation constants for …

The Influence Of Temperature And Some Other Factors On The Biological And Nonbiological Oxidation Of Chalcopyrite, Pyrite And Copper Sulfide, Ezra Revier Palmer

Theses and Dissertations

The purpose of this study was: (1) to find the effect of temperature on the wet oxidation of chalcopyrite, pyrite, and copper sulfide over the biological and nonbiological range; (2) to determine the influence of ferrous and ferric iron and free oxygen(air) on the oxidation. The sulfide minerals studied were oxidized over a range of temperatures between 25° to 75° C. The optimum biological oxidation occurred near 35° C. The nonbiological oxidation was very slow at low temperatures but increased with increasing temperature. The effect of solutions used in leaching the various sulfides over the temperature range differred. A synthetic …

Investigation Of The Platinum-Rich Portion Of The Platinum-Tantalum Phase Diagram, Bob Dean Browning

Theses and Dissertations

The Pt-Ta binary system was investigated at two isotherms;1000°C and 1500°C, and at eleven alloy compositions in the range of 50 to 100 atomic percent platinum. The alloys were examined by x-ray diffraction and metallography. Three intermetallic compounds, Pt₂Ta, Pt₃Ta, and Pt₄Ta were found to exist in this composition range. The Pt₄Ta intermetallic appeared only at the 1500°C isotherm. Platinum dissolved tantalum substitutionally to 90 atomic percent at 1500 °C and to approximately 80 atomic percent at 1000 °C.

The Surficial Geology Of Southern Logan County, North Dakota, John W. Bonneville

Theses and Dissertations

Southern Logan County, North Dakota, was glaciated at least three different times during the Pleistocene epoch. Scattered patches of highly weathered iron-cemented drift found in the area of eroded Cretaceous bedrock in southwest-era Logan County are very possibly pre-Wisconsinan in age. Two younger drift sheets of Wisconsinan age cover the remaining portion of the county. One of these drifts, the Napoleon drift, is probably early Wisconsinan, and the other, the Burnstad-Streeter drift, is likely late Wisconsinan in age.

A great diversity in types of glacial topography and individual features is found in southern Logan County. Excellent examples of end moraine, …