Fine structure analysis

Y. Nagai, T. Yamamoto, T. Tanaka, S. Yoshida, T. Nonaka, T. Okamoto, A. Suda, and M. Sugiura, X-ray absorption fine structure analysis of local structure of Ce02-Zr02 mixed oxides with the same composition ratio (Ce/Zr = 1), Catal. Today 74, 225-234 (2002). 

Sankai P., Lee, J. H. and Shanmugam, K. T. (1985) Cloning of hydrogenase genes and fine structure analysis of an operon essential for H2 metabolism in Escherichia coli. J. Bacteriol., 162, 353-60. 

The ejected photoelectron may be approximated by a spherical wave, which is backscattered by the neighboring atoms. The interference between the outgoing forward scattered, or ejected, photoelectron wave and the backscattered wave gives rise to an oscillation in the absorbance as a function of the energy of the incident photon. These oscillations, which may extend up to 1000 eV above the absorption edge, are called the EXAFS, extended X-ray absorption fine structure. Analysis of the EXAFS provides information regarding the identity of, distance to, and number of near neighboring atoms. 

Haschke et al. (2000) have demonstrated the occurrence of a superoxide Pu02+JC(s) that reportedly formed between 25 and 350 C and contained Pu(VI). Runde et al. (2002) reported XAS evidence for the existence of Pu(V) instead of Pu(VI). Fine structure analysis for the Pu solid precipitated at 90 °C in a Yucca Mountain groundwater was compared with data for a Pu02(S) standard. The measured Pu-O distance of 0.185 nm is characteristic for Pu(V) and agrees well with the measured Pu-O bond distance of the Pu(V)02(aq) ion at 0.181 nm. The Pu-O bonds in hexavalent Pu compounds are much shorter. Other details in the X-ray absorption fine structure spectra supported the assignment of Pu as Pu(V). At ambient temperatures, oxidation of Pu(IV) was extremely slow and formation of Pu(V) was not observed. 

Fractional values may also arise if a side chain makes one set of interactions with one element of structure and a further set with a different element, and these elements react in different ways in unfolding. This possibility was noticed by examining the structure of barnase and performing a fine-structure analysis by making systematic mutations in the side chains involved e.g., lie — Val — Ala — Gly.38... 

In addition to the absorption maxima of the carotenoids, the shape of the spectra provides important information for identification of purified carotenoid extracts or pure standard (while the identity of the standard is generally not in question, it is a good idea to check the purity by fine structure analysis). Fine structure... 

Manceau et al. [ 129] studied the application of X-ray absorption fine-structure analysis (EXAES) to the speciation and quantification of the forms of trace metals in solid materials. Palladium was studied in particular. 

Wherever this is applicable in rotational fine structure analysis, the customary approach involves analyzing the spectra in terms of a near prolate or oblate top. Deviations from this approximation decrease with increasing quantum number K. For a more extensive discussion, for example of the subband structure in symmetric top spectra, the reader is referred to Allen and Cross (1963). 

Scheuring, E., Padmakumar, R., Banerjee, R., and Chance, M. R., 1997, Extended X-ray absorption fine structure analysis of coenzyme B12 bound to methylmalonyl-coenzyme A mutase using global mapping techniques, J. Am. Chem. Soc. 119 12192012200. 

Fine structure analysis of human bronchial epithelial cells glycans using MALDI-MS profiling... 

Extended x-ray fine structure analysis can determine the identity, coordination number, and distance of atoms surrounding a given element. 

Hattori T, McGeer EG, McGeer PL (1978) Fine structural analysis of cortico-striatal pathway. J. Comp. Neurol, 185, 347-354. 

EPR = Electron paramagnetic resonance EXAFS = Extended X-ray fine structure analysis ESEEM = Electron spin echo envelope spectroscopy XANES = X-ray absorption near edge structure analysis NMR = Nuclear magnetic resonance. 

R.L. Park. Extended Fine Structure Analysis of Materials. Appl. Surf. Sci. 13 231 (1982). 

It was confirmed by two measurements individually, (a) epr fine structure analysis and (b) determination of magnetization, that the carbenes 2 (n = 4 and... 

EXAFS Extended X-ray absorption fine structure (analysis), see also ... 

EAPFS Extended (Electron) Appearance Potential Fine Structure Analysis ... 

Extended X-ray absorption fine structure analysis of ferritin and imferon (a synthetic complex of iron oxide coated with dextran) show that the nearneighbour environment around the iron atom in the two macromolecules is identical. 

Iron-dextran, a synthetic therapeutic complex of iron oxide coated with dextran (Imferon ), has been shown to have properties similar to those of ferritin, a natural complex of iron oxide encased in protein.Both maintain high concentrations of iron in solution at physiological pH, and release iron relatively slowly in vivo. Extended AT-ray absorption fine structure analysis showed that the near-neighbour environment around the average iron atom in ferritin and iron-dextran is identical for the first three shells, which may explain the similarity of iron release in vivo. The results suggest that iron-dextran will be a useful model compound in studies of the relation of the iron core and protein in ferritin to function.i... 

An earlier fine-structure analysis of the A X emission spectrum is to be found in [14]. 

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