EPR electron paramagnetic

Abbreviations EPR, electron paramagnetic resonance FITC, fluorescein-5 -isothiocyanate lAEDANS, iV-iodoacetyl-N -(5-sulfo-l-naphthyl)ethylenediamine NCD, fluorescent yV-cyclohexyl-N -(4-dimethyl-amino-a-naphthyl)carbodiimide RITC, rhodamine-5 -isothiocyanate DPPE, dipalmitoylphosphatidyl-ethanolamine PE, egg phosphatidyl-ethanolamine ANS, 8-anilino-l-naphthalene sulfonate DPH, diphenylhexatriene e-ADP, l,iV -ethanoadenosine-5 -diphosphate TNP-ADP, 2 [3 ]-0-(2,4,6-trinitrophe-nyl)adenosine-5 -diphosphate. 

The description theoretical study of defects frequently refers to some computation of defect electronic structure i.e., a solution of the Schrodin-ger equation (Pantelides, 1978 Bachelet, 1986). The goal of such calculations is normally to complement or guide the corresponding experimental study so that the defect is either properly identified or otherwise better understood. Frequently, the experimental study suffices to identify the basic structure of the defect this is particularly true when the system is EPR (electron paramagnetic resonance) active. However, if the computational method properly simulates the defect, we are provided with a wealth of additional information that can be used to reveal some of the more basic and general features of many-electron defect systems and defect reactions. 

EPR electron paramagnetic resonance (also known as electron spin resonance (ESR))... 

EPR Electron Paramagnetic Resonance EHT Differential Overlap Extended Hiickel Theory... 

It is worth recalling that other types of probes are used in practice for example, radioactive tracers, with their well-known drawback of their radioactivity, and EPR (electronic paramagnetic resonance) probes that provide information mainly on molecular mobility. In contrast to these probes, which are used in rather limited fields of applications, fluorescent probes can offer a wealth of information in various fields, as shown in Table 1.4. The various examples described in this book will demonstrate their outstanding versatility. 

Figure 1.1 The electiomagnetic spectrum, showing the different microscopic excitation sources and the spectroscopies related to the different spectral regions. XRF, X-Ray Fluorescence AEFS, Absorption Edge Fine Structure EXAFS, Extended X-ray Absorption Fine Structure NMR, Nuclear Magnetic Resonance EPR, Electron Paramagnetic Resonance. The shaded region indicates the optical range.

Table 5.2 Summary of selected analytical methods for molecular environmental geochemistry. AAS Atomic absorption spectroscopy AFM Atomic force microscopy (also known as SFM) CT Computerized tomography EDS Energy dispersive spectrometry. EELS Electron energy loss spectroscopy EM Electron microscopy EPR Electron paramagnetic resonance (also known as ESR) ESR Electron spin resonance (also known as EPR) EXAFS Extended X-ray absorption fine structure FUR Fourier transform infrared FIR-TEM Fligh-resolution transmission electron microscopy ICP-AES Inductively-coupled plasma atomic emission spectrometry ICP-MS Inductively-coupled plasma mass spectrometry. Reproduced by permission of American Geophysical Union. O Day PA (1999) Molecular environmental geochemistry. Rev Geophysics 37 249-274. Copyright 1999 American Geophysical Union...

Shorthand notations such as ET (electron transfer), HAT (hydrogen atom transfer), BDE (bond dissociation energy), NHE (normal hydrogen electrode), CV (cyclic voltammetry), LFP (laser flash photolysis), EPR (electron paramagnetic resonance) and KIE (kinetic isotope effect) will be used throughout the chapter. In addition, recurring chemical compounds such as TEMPO (2,2,6,6-tetramethylpiperidine-Ai-oxyl), HBT (1-hydroxyben-zotriazole), BTNO (benzotriazole-A-oxyl), HPI (iV-hydroxyphthalimide), PINO (phthal-imide-iV-oxyl), NHA (A-hydroxyacetanilide) and a few others will be referred to by means of the capital-letter acronym. 

CW, continuous wave Cys, cysteine DFT, density functional theory ENDOR, electron nuclear double resonance ehba, 2-ethyl-2-hydroxybutanoate2 EPR, electron paramagnetic resonance Glc6P, D-glucose 6-phosphate GSH, reduced glutathione HEPES, 4-(2-hydroxyethyl)-l-piperazineethanesulfonic acid Hex, aldohexose ... 

Poly (methyl methacrylate) was also subjected to mechanical reaction in a vibrating mill in common solvent for several monomers (ethylene, acrylic acid and its esters, acrylonitrile and styrene) at temperatures from —196 to 20° C (22). The formation of macroradicals and their reactions were followed by EPR (electron paramagnetic resonance). The macroradicals reacted with vinyl monomers at temperatures less than —100° C, while quinones underwent reaction as low as —196° C. The same experiments were performed also with polystyrene and polybutylenedimethacrylate. The radicals from polystyrene were more reactive than those from poly(methyl methacrylate). 

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