Continuous electron spin resonance

McLauchlan K A 1990 Continuous-wave transient electron spin resonance Modern Pulsed and... 

Continuous-Wave Electron Spin Resonance ed L Kevan and M Bowman (New York Wiley) oh 7, pp 285-363... 

Allgeler J, DIsselhorst A, Weber R, Wenckebach W and Schmidt J 1990 High-frequency pulsed electron spin resonance Modern Pulsed and Continuous-Wave Electron Spin Resonance ed L Kevan and M K Bowman (New York Wley) ch 6, pp 267-83... 

Kevan, L. and M. K. Bowman (1990). Modem Pulsed and Continuous-Wave Electron Spin Resonance. New York Wiley. 

Modern Pulsed and Continueous-Wave Electron Spin Resonance, ed. L. Kevan and M.K. Bowman, John Wiley, New York, 1990. 

Various optical detection methods have been used to measure pH in vivo. Fluorescence ratio imaging microscopy using an inverted microscope was used to determine intracellular pH in tumor cells [5], NMR spectroscopy was used to continuously monitor temperature-induced pH changes in fish to study the role of intracellular pH in the maintenance of protein function [27], Additionally, NMR spectroscopy was used to map in-vivo extracellular pH in rat brain gliomas [3], Electron spin resonance (ESR), which is operated at a lower resonance, has been adapted for in-vivo pH measurements because it provides a sufficient RF penetration for deep body organs [28], The non-destructive determination of tissue pH using near-infrared diffuse reflectance spectroscopy (NIRS) has been employed for pH measurements in the muscle during... 

Gray, H. B. and Malmstrom, B. G. (1989). Biochemistry 28, 7449 Grupp, A. and Mehring, M. (1990). In Modern Pulsed and Continuous Wave Electron Spin Resonance, p. 195. Wiley, New York... 

Figure 8 shows the relationship between the hydrogenolytic behaviors and reduction time (52). The Mo(V) in the reduced catalyst is related neither to the catalytic activity nor to the hydrogenolytic behaviors. The electron spin resonance signal reaches a maximum within a very short reduction period, then drops and reaches a constant with continued reduction. This variation of Mo(V) concentration is compatible with the data obtained by Seshadri and Petrakis (67) and Massoth (55). The changes in the bja ratio and the catalytic activity with the time of reduction agree with the amount of Mo(IV) species reported by Massoth (55), as quoted in Fig. 8. 

Electron spin resonance continued) di(t rt-butyl)methoxide complexes, 26 323 dithiocarbamate complexes, 23 218-220,... 

The phonon is of importance to many phenomena electron mobility, optical absorption, electron spin resonance, electron tunneling, and superconductivity. The phonon spectrum represents a detailed picture of the forces that hold solids together. Thus, it is clear why the phonon has been and will continue to be of fundamental importance in solid-state physics. 

Hildenbrand K (1995) Spin-trapping studies of the reaction of the sulfate radical ion with N1-substituted pyrimidine bases. Comparison with continuous-flow electron paramagnetic resonance experiments.) Chem Soc Perkin Trans 2 2153-2162 Hildenbrand K, Schulte-Frohlinde D (1997) Time-resolved EPR studies on the reaction rates of per-oxyl radicals of polyfacrylic acid) and of calf thymus DNA with glutathione. Re-examination of a rate constant for DNA. Int J Radiat Biol 71 377-385 Hildenbrand K, Behrens G, Schulte-Frohlinde D, Herak JN (1989) Comparison of the reaction OH and S04- radicals with pyrimidine nucleosides. An electron spin resonance study in aqueous solution. J Chem Soc Perkin Trans 2 283-289... 

Termination steps are negligible from the beginning of reaction. This is based on the idea that radicals become trapped in highly crosslinked polymer coils and on the observed continuous increase of free radicals concentration by electron spin resonance (ESR). 

Electron paramagnetic resonance spectroscopy, also known as electron spin resonance (ESR) spectroscopy, detects the excitation of electron spins in an applied external magnetic field.13 Conventional continuous-wave (CW) EPR is based on resonance of a fixed-frequency standing microwave to excite some of the electrons in Zeeman-split spin multiplets to undergo a transition from a lower Ms level to a higher... 

L Kevan, M K Bowman, Modem Pulsed and Continuous-wave Electron Spin resonance, Wiley, New York, 1990... 

The properties are most useful when there are several closely overlapping peaks, and higher order derivatives are commonly employed, for example in electron spin resonance and electronic absorption spectroscopy, to improve resolution. Figure 3.11 illustrates the first and second derivatives of two closely overlapping peaks. The second derivative clearly indicates two peaks and fairly accurately pinpoints their positions. The appearance of the first derivative would suggest that the peak is not pure but, in this case, probably does not provide definitive evidence. It is, of course, possible to continue and calculate the third, fourth, etc., derivatives. 

Attempts to apply thermoluminescence (TL) and electron spin resonance (ESR) data to date soil horizons, and to use ESR to date bone are underway. As yet, there are no agreed-upon criteria on which to evaluate the overall reliability of age inferences based on ESR data (13). It has been suggested (14) that in some circumstances the obsidian hydration method can be used to infer chronological age over in excess of 100,000 years (14). However, obsidian is not a widespread natural resource and some of the hydration rate structures appear to yield problematic results. Amino acid racemization (AAR) values can be used under some conditions to infer accurate age values for bone, but seriously anomalous values can be obtained (15, 16). The conditions under which AAR values can be used to accurately infer age, particularly for bone samples, continue to be investigated. 

The first experimental observation of electron spin resonance was made on an iron compound by Zavoisky in Russia in 1944. A year later Purcell and Bloch and their collaborators observed independently nuclear magnetic resonance in condensed matter. While the celebrated Purcell and Bloch discoveries have sparked an explosive wave of research on nuclear magnetic resonance throughout the world, little activity on electron spin resonance followed immediately after the first success. In fact, even Zavoisky did not continue working in the field of ESR, and the development of the technique was almost exclusively left to the physicists in the decade after the war. Indeed, the potential diversity of applications of ESR to chemistry could hardly have been foreseen in the earlier days. 

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