Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Hellmann-Feynman Theorem In Thomas-Fermi And Related Theories, Jerry Goodisman Jul 1970

Hellmann-Feynman Theorem In Thomas-Fermi And Related Theories, Jerry Goodisman

Chemistry - All Scholarship

The general Hellmann-Feynman theorem (derivative of energy with respect to a parameter = expectation value of derivative of Hamiltonian) is proved for theories in which the electron density is determined by making the energy functional stationary. Some simple applications are given.


The Enzymatic Oxidation Of Aldehydes By Xanthine Oxidase, Duane Beal Gregory Jun 1970

The Enzymatic Oxidation Of Aldehydes By Xanthine Oxidase, Duane Beal Gregory

All Master's Theses

As early as sixty years ago, the existence of an enzyme from mammalian tissues which catalyzed the oxidation of xanthine and hypoxanthine was recognized. The name given the enzyme was derived from its earliest recognized action, hence xanthine oxidase. Although little is known about the biological functions of the enzyme, the high affinity shown for xanthine and hypoxanthine may indicate that these are the most significant substrates biologically.


High Pressure Spectral Chemistry Of Selected Organic Compounds, Frank William Linsley Jun 1970

High Pressure Spectral Chemistry Of Selected Organic Compounds, Frank William Linsley

Theses and Dissertations

The series of compounds indicated by the formular C_6H_5-(CH=CH)n-C_6H_5 change in color from white (colorless) to yellow to orange to red to deep red as n increases from 1 to 12. Stilbene is the first compound of this series (n=1). Under pressure, exerted by a diamond anvil press, stilbene can be seen to change color from white to yellow to red as increasing pressure is applied. Similar color changes are observed for the compounds where n=2,3, and 4 when subjected to similar pressure. This study records and reports the spectra versus pressure for these compounds.


Modified Weizsäcker Corrections In Thomas-Fermi Theories, Jerry Goodisman Jan 1970

Modified Weizsäcker Corrections In Thomas-Fermi Theories, Jerry Goodisman

Chemistry - All Scholarship

We consider theories in which a kinetic-energy correction (h2322m)[2] (=density) is added to the usual Thomas-Fermi term. A treatment based on the WKB method and expected to be valid for large r shows =1 here, as found experimentally. For small r, =1 is needed to give proper behavior of, but other arguments suggest that the Thomas-Fermi term be dropped here.


Modified Quantum-Statistical Calculations For Atomic Electron Densities, Jerry Goodisman Jan 1970

Modified Quantum-Statistical Calculations For Atomic Electron Densities, Jerry Goodisman

Chemistry - All Scholarship

We attempt to overcome one of the shortcomings in the Thomas-Fermi and related theories for atoms by connecting a quantum-mechanical electron density for the region near the nucleus to a density given by a statistical model. The joining may be done in a nonarbitrary manner: All parameters are determined. It suffices to use a very crude and easily calculated approximation to the density to start with, so the calculation is quite easy. The resulting electron density is in much better agreement with reality than that from the unmodified theories.


Acid-Base Catalysis Of The Enolization Of Acetone, Janet Louise Larson Jan 1970

Acid-Base Catalysis Of The Enolization Of Acetone, Janet Louise Larson

Undergraduate Honors Theses

Measurements are reported on the rate of iodination of acetone at 25°c in arsenate, phosphate, and diethylmalonic acid buffers at a constant ionic strength of 0.2. Unlike earlier results which indicate that in acetic acid buffer the expression for the reaction velocity contains an appreciable kinetic term involving the product of the concentrations of acid and anion, it has been found from the present work that such a term is experimentally immeasurable for the above mentioned buffers. This finding coupled with the relatively powerful catalysis by the phosphate and arsenate dianions could imply the simultaneous participation of these species in …