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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Galois Theory and its Application to the Problem of Solvability by Radicals of an Equation Over a Field of Prime or Zero Characteristic

Ronald, Rupert George 05 1900 (has links)
In Part I of the thesis an account is given of the basic algebra of extension fields which is required for the understanding of Galois theory. The fundamental theorem states the relationships of the subgroups of a permutation group of the root field of an equation to the subfields which are left invariant by these subgroups. Extensions of the basic theorem conclude Part I. In part II the solvability of equations by radicals is discussed, for fields of characteristic zero. A discussion of finite fields and primitive roots leads to a criterion for the solvability by radicals of equations over fields of prime characteristic. Finally, a method for determining the Galois group of any equation is discussed. Most of the material in the introductory chapters is taken from Artin's: Galois Theory (cf. p. 120). / Thesis / Master of Arts (MA)
332

REPERFUSION-INDUCED MODULATION OF CARDIAC MITOCHONDRIAL FUNCTION BY FREE RADICALS AND CALCIUM

Sadek, Hesham A. 04 June 2004 (has links)
No description available.
333

Spectroscopy Studies of Free Radicals and Ions Containing Large Amplitude Motions

Huang, Meng 02 August 2018 (has links)
No description available.
334

The kinetics of a methyl methacrylate polymerization initiated by the stable free radicals in irradiated polytetrafluoroethylene and properties of the resultant graft polymer

Donato, Karen Ann Ehnot January 1987 (has links)
No description available.
335

Near IR cavity ringdown spectroscopy of peroxy radicals

Zalyubovsky, Sergey J. 30 September 2004 (has links)
No description available.
336

Computational studies of combustion processes and oxygenated species

Hayes, Carrigan J. 24 August 2007 (has links)
No description available.
337

The role of lipid peroxidation in pancreatic islet function and destruction in type 1 Diabetes Mellitus /

Iovino, Giugetta. January 1997 (has links)
No description available.
338

ESR investigation of some free-radical adducts

Kozloski, Richard Peter 15 July 2010 (has links)
The effect of steric strain on the esr hyperfine coupling constants of several free-radical adducts of perfluoropropene and perfluoro-2-butene were investigated. Silyl, hydroxyalkyl, thiyl and alkoxy free radicals, which were generated by photo-irradiation, reacted with these olefins to form free-radical adducts. Trends in the esr hfs were then looked for in each class of adducts. The thiyl and alkoxy radicals were found to be unsuitable for this type of study due to the low degree of steric strain produced by these species in the adducts. Trends toward higher a-Fβ/CF₃ hfs and lower a<sup>Fα</sup> hfs were observed for the silyl and hydroxyalkyl radical adducts as the steric strain in the adduct was increased. The ratio of the <sup>Fα</sup> to a-Fβ/CF₃ hfs was shown to be a good measure of the degree of steric strain in these radical adducts. The possibility that the (Me₃Si)₂CHC(SiMe₃)₂ free radical, which has been reported to contain an "esr invisible" β-H, might be misidentified was investigated. Our conclusion was that the β-H is present and has not been replaced by a t-butoxy group. / Ph. D.
339

Internal pressure's role in the selectivity of the bromine radical

Hulvey, Glenn A. 10 June 2009 (has links)
The results of our studies demonstrate a link between selectivity in free radical brominations and the internal pressure of solvent. The study encompassed l8 solvents and/or mixtures over which the rate constant ratio for SH2 ring opening of cyclopropylbenzene (kC) vs hydrogen abstraction from toluene (kH) by bromine atom was found to vary by nearly a factor of twenty as a function of solvent. The observed rate constant ratios correlate with the cohesive energy density of the solvent, which is approximately equal to the internal pressure (kC/kH is found to increase with increasing solvent pressure) for the solvents used in this study. A similar competition pitting cyclopropylbenzene against p-chlorotoluene shows the same solvent effect. It is suggested that the observed variation in selectivity "with solvent pressure occurs because the volume of activation with kC is more negative than for kH by about 20 cm3/mol. / Master of Science
340

Structure and microwave spectrum of the 2-cyano-2-propyl radical

Claytor, Robinson C. P. January 1988 (has links)
The rotational spectra of the 2-cyano-2-propyl and d⁶-2·cyano-2-propyl radicals were observed using a Stark modulated spectrometer. The radicals were generated in the gas phase by UV irradiation of sublimed azoisobisbutyronitrile. They were detectable in the cell for approximately one hour. Thirty-three transitions were assigned for (CH₃)₂CCN and twenty-one for (CD₃)₂CCN. The rigid rotor rotational constants determined by calculation of the hypothetical unsplit rotational transitions are A=8276.7, B=3919.7, C=2751.5Mhz for (CH₃)₂CCN and A=6241.3, B=3490.7, C=2372.6Mhz for (CD₃)₂CCN. A program to calculate the fine splittings and hyperfine splittings due to the ¹⁴N nucleus and six protons was written. The spin rotation constants determined for the two species were E<sub>aa</sub>=-69.9, E<sub>bb</sub>=-36.1, E<sub>cc</sub>=2.7Mhz and E<sub>aa</sub>=-55.4, E<sub>bb</sub>=-32.6 Mhz for (CH₃)₂CCN and (CD₃)₂CCN respectively. The hyperfine coupling constants for ¹⁴N are identical for both isotopic species and were found to be T<sub>aa</sub>=-17.2, T<sub>bb</sub>=-17.1 and T<sub>cc</sub>=34.4 Mhz. The proton and deuteron hyperfine splittings were not resolved. The structural parameters determined from an <r₀> fit of the moments are r<sub>CN</sub>=1.18A, r<sub>CC</sub>=1.42A, r<sub>CMe</sub>=1.50A and CCMe=119.3°. The C₄N skeletal framework was found to be planar. / Ph. D.

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