Electron paramagnetic resonance saturation

Subczynski, W. K., J. Widomska, A. Wisniewska, and A. Kusumi. 2007a. Saturation-recovery electron paramagnetic resonance discrimination by oxygen transport (DOT) method for characterizing membrane domains. In Methods in Molecular Biology Lipid Rafts, ed. T. J. McIntosh, Vol. 398, pp. 145-159, Totowa, NJ Humana Press. 

Thomas, D.D., Dalton, L.R., and Hyde, J.S. 1976. Rotational diffusion studied by passage saturation transfer electron paramagnetic resonance. The Journal of Chemical Physics 65 3006-3024. 

Electron-nuclear double resonance (ENDOR) spectroscopy A magnetic resonance spectroscopic technique for the determination of hyperfine interactions between electrons and nuclear spins. There are two principal techniques. In continuous-wave ENDOR the intensity of an electron paramagnetic resonance signal, partially saturated with microwave power, is measured as radio frequency is applied. In pulsed ENDOR the radio frequency is applied as pulses and the EPR signal is detected as a spin-echo. In each case an enhancement of the EPR signal is observed when the radiofrequency is in resonance with the coupled nuclei. 

Depending on concentration of a hydrochloric acid during lixiviation of powders the process of saturation by gas develops ambiguously it has a sine wave character. The established dependence of an output in a solution of ions trivalent titanium on the concentration of a solution according to data, obtained by the method of electronic paramagnetic resonance, has shown that at small time of exposure (50-100 hrs) the output of ions of titanium in a solution proceeds with the increasing speed. The pure powders react with environment less actively, polluted -more intensively. The speed of saturation of powders by gas at corrosion in solutions of a hydrochloric acid is increased with growth of concentration, and then is sharply reduced. 

The reagent alkali metal/naphthalene in tetrahydrofuran reacts with graphite, polynuclear aromatics, and various coals to form chemically reduced products. In the present paper, we emphasize the use of electron paramagnetic resonance data, in the form of g values, linewidths, radical densities, and saturation characteristics, to analyze the reduced coal products and to infer certain differences between the reduced coals and the anions of graphite and simple aromatic hydrocarbons. Additionally, because the interaction of coals with alkali metal/naph-thalene requires much time for completion, we have investigated internal decomposition pathways for the... 

Electron paramagnetic resonance spectroscopy has contributed greatly to the understanding of the configuration of the iron in LAM. In initial spectroscopic studies, the as-purified enzyme exhibited a rhombic spectrum at 10 K. The signal was centered at g = 2.007, and underwent power saturation at the same temperature in a homogeneous manner with a = 15 2 mW. At higher temperatures the... 

The experiments with 5,6-dihydrothymine are a preliminary attempt to compare rates of formation of transients by addition and by abstraction. Dihydrothymine is the saturated analog of thymine. The transient species which it forms by reaction with OH have an absorption maximum at 400 n.m. at pH 7 and at 320 n.m. or lower at pH 12.4. The rate of formation of these transients appears to be slightly less than one-third of the rate of formation of transients by addition to thymine. At pH 7, OH adds to the 5,6 double bond of thymine. The aqueous solution radiation chemistry of dihydrothymine has not been investigated, but electron paramagnetic resonance (EPR) studies in the solid phase show that H atoms abstract... 

Altenbach C, Eroncisz W, Hyde JS, Hubbell WL (1989) Conformation of spin-labeled melittin at membrane surfaces investigated by pulse saturation recovery and continuous wave power saturation electron-paramagnetic resonance. Biophys J 56 1183-1191... 

Federicamycin A (= NSC-305264) spontaneously forms an oxidised free radical with electron transfer to O2 (Hilton et al. 1986). The observed hyper-fine structure of this radical is consistent with one-electron oxidation of the quininoid group. After federicamycin A is exposed to O2, an electron paramagnetic resonance (EPR) signal is observed with axial symmetry with temperature and power saturation behaviour suggestive of 02 . Spin-trapping EPR studies demonstrated that the drug reduces O2 to 02 ". and H2O2 to HO. ... 

As already proposed by Albert Overhauser [203] in 1953 and subsequently confirmed experimentally by Carver and Slichter [204, 205], electron spin polarization in solid metals can be transferred to nuclear spins if the unpaired conducting electrons are saturated by irradiation with the corresponding electron paramagnetic resonance (EPR) frequency. As a result, nuclear spin polarization may be enhanced by the factor yJyt,. Likewise, stable organic radicals can be used as polarizing agents. 

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