The Experts below are selected from a list of 201 Experts worldwide ranked by ideXlab platform
K.e Attenkofer - One of the best experts on this subject based on the ideXlab platform.
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X-ray absorption Fine Structure study of manganese compounds
Journal of Alloys and Compounds, 2001Co-Authors: Robert Nietubyc, Ewa Sobczak, K.e AttenkoferAbstract:Abstract This work is aimed at the comparative analysis (both theoretical and experimental) of the Mn K-edge X-ray absorption Fine Structure in selected manganese compounds, i.e. MnS, MnPO 4 ·H 2 O and MnO 2 measured in transmission mode by using synchrotron radiation in HASYLAB. The results were analysed by performing the Fine Structure calculation with feff8 programme. The calculations gave results which conform to the experimental data. We observed an evolution of the pre-edge features and a shift of the main absorption edge toward higher energy with the Mn oxidisation degree.
Sara K. Mamo - One of the best experts on this subject based on the ideXlab platform.
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Processing of temporal Fine Structure as a function of age
Ear and hearing, 2010Co-Authors: John H. Grose, Sara K. MamoAbstract:Objectives:The purpose of this study was to determine whether the processing of temporal Fine Structure diminishes with age, even in the presence of relatively normal audiometric hearing. Temporal Fine Structure processing was assessed by measuring the discrimination of interaural phase differences
Michael Sherbon - One of the best experts on this subject based on the ideXlab platform.
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Golden Ratio Geometry and the Fine-Structure Constant
Journal of Advances in Physics, 2019Co-Authors: Michael SherbonAbstract:The golden ratio is found to be related to the Fine-Structure constant, which determines the strength of the electromagnetic interaction. The golden ratio and classical harmonic proportions with quartic equations give an approximate value for the inverse Fine-Structure constant the same as that discovered previously in the geometry of the hydrogen atom. With the former golden ratio results, relationships are also shown between the four fundamental forces of nature: electromagnetism, the weak force, the strong force and the force of gravitation.
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Fine-Structure constant from Sommerfeld to Feynman
Journal of Advances in Physics, 2019Co-Authors: Michael SherbonAbstract:The Fine-Structure constant, which determines the strength of the electromagnetic interaction, is briefly reviewed beginning with its introduction by Arnold Sommerfeld and also includes the interest of Wolfgang Pauli, Paul Dirac, Richard Feynman and others. Sommerfeld was very much a Pythagorean and sometimes compared to Johannes Kepler. The archetypal Pythagorean triangle has long been known as a hiding place for the golden ratio. More recently, the quartic polynomial has also been found as a hiding place for the golden ratio. The Kepler triangle, with its golden ratio proportions, is also a Pythagorean triangle. Combining classical harmonic proportions derived from Kepler's triangle with quartic equations determine an approximate value for the Fine-Structure constant that is the same as that found in our previous work with the golden ratio geometry of the hydrogen atom. These results make further progress toward an understanding of the golden ratio as the basis for the Fine-Structure constant.
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Fundamental Nature of the Fine-Structure Constant
International Journal of Physical Research, 2014Co-Authors: Michael SherbonAbstract:Arnold Sommerfeld introduced the Fine-Structure constant that determines the strength of the electromagnetic interaction. Following Sommerfeld, Wolfgang Pauli left several clues to calculating the Fine-Structure constant with his research on Johannes Kepler's view of nature and Pythagorean geometry. The Laplace limit of Kepler's equation in classical mechanics, the Bohr-Sommerfeld model of the hydrogen atom and Julian Schwinger's research enable a calculation of the electron magnetic moment anomaly. Considerations of fundamental lengths such as the charge radius of the proton and mass ratios suggest some further foundational interpretations of quantum electrodynamics.
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Wolfgang Pauli and the Fine-Structure Constant
Journal of Science, 2012Co-Authors: Michael SherbonAbstract:Wolfgang Pauli was influenced by Carl Jung and the Platonism of Arnold Sommerfeld, who introduced the Fine-Structure constant. Pauli's vision of a World Clock is related to the symbolic form of the Emerald Tablet of Hermes and Plato's geometric allegory otherwise known as the Cosmological Circle attributed to ancient tradition. With this vision Pauli revealed geometric clues to the mystery of the Fine-Structure constant that determines the strength of the electromagnetic interaction. A Platonic interpretation of the World Clock and the Cosmological Circle provides an explanation that includes the geometric Structure of the pineal gland described by the golden ratio. In his experience of archetypal images Pauli encounters the synchronicity of events that contribute to his quest for physical symmetry relevant to the development of quantum electrodynamics.
Lauren G. Baranowski - One of the best experts on this subject based on the ideXlab platform.
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The influence of common stimulus parameters on distortion product otoacoustic emission Fine Structure.
Ear and hearing, 2012Co-Authors: Tiffany A. Johnson, Lauren G. BaranowskiAbstract:OBJECTIVES To determine whether common approaches to setting stimulus parameters influence the depth of Fine Structure present in the distortion product otoacoustic emission (DPOAE) response. Because the presence of Fine Structure has been suggested as a possible source of errors, if one of the common parametric approaches results in reduced Fine-Structure depth, it may be preferred over other approaches. DESIGN DPOAE responses were recorded in a group of 21 subjects with normal hearing for 1/3-octave intervals surrounding 3 f2s (1, 2, and 4 kHz) at three L2s (30, 45, and 55 dB SPL). For each f2 and L2 combination, L1 and f2/f1 were set according to three commonly used parametric approaches. These included a simple approach, the approach recommended by Kummer et al., and the approach described by Johnson et al. These three approaches primarily differ in the recommended relationship between L1 and L2. For each parametric approach, DPOAE Fine Structure was evaluated by varying f2 in small steps. Differences in DPOAE level and DPOAE Fine-Structure depth across f2, L2, and the various stimulus parameters were evaluated using repeated-measures analysis of variance. RESULTS As expected, significant variations in DPOAE level were observed across the three parametric approaches. For stimulus levels #45 dB SPL, the simple stimuli resulted in lower DPOAE levels than were observed for other approaches. An unexpected finding was that stimulus parameters developed by Johnson et al., which were believed to produce higher DPOAE levels than other approaches, produced the lowest DPOAE levels of the three approaches when f2 = 4 kHz. Significant differences in Fine-Structure depth were also observed. Greater Fine-Structure depth was observed with the simple parameters, although this effect was restricted to L2 # 45 dB SPL. When L2 = 55 dB SPL, all three parametric approaches resulted in equivalent Fine-Structure depth. A significant difference in Fine-Structure depth across the 3 f2s was also observed. The interval surrounding 2 kHz was associated with greater Fine-Structure depth than the intervals surrounding 1 and 4 kHz. CONCLUSIONS The simple stimulus parameters resulted in more Fine Structure than the other parametric approaches; however, this effect was restricted to L2 # 45 dB SPL. At the moderate stimulus levels used in most clinical applications of DPOAEs (L2 = 55 dB SPL), all three approaches resulted in similar Fine-Structure depths. These findings suggest that manipulating stimulus parameters, particularly the L1, L2 relationship, is not an effective technique for reducing Fine Structure, except at the lowest stimulus levels, and that all the common parameters result in equivalent Fine Structure for moderate stimulus levels. These results also suggest that the stimulus parameters used in future studies of the clinical implications of Fine Structure may be relatively unimportant, unless stimulus levels #45 dB SPL will be evaluated.
Robert Nietubyc - One of the best experts on this subject based on the ideXlab platform.
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X-ray absorption Fine Structure study of manganese compounds
Journal of Alloys and Compounds, 2001Co-Authors: Robert Nietubyc, Ewa Sobczak, K.e AttenkoferAbstract:Abstract This work is aimed at the comparative analysis (both theoretical and experimental) of the Mn K-edge X-ray absorption Fine Structure in selected manganese compounds, i.e. MnS, MnPO 4 ·H 2 O and MnO 2 measured in transmission mode by using synchrotron radiation in HASYLAB. The results were analysed by performing the Fine Structure calculation with feff8 programme. The calculations gave results which conform to the experimental data. We observed an evolution of the pre-edge features and a shift of the main absorption edge toward higher energy with the Mn oxidisation degree.
