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A flow-type cell was developed for measuring Compton scattering spectra of heat-sensitive aqueous solution. Compton scattering spectra of water and ethanol were measured in the region from ambient conditions to 623 K and 20 MPa. Compton profiles derived from measurement with the flow-type cell were comparable with those in the literature. Results obtained from the flow-type cell showed that delocalization of electronic charge density of water and ethanol at high temperatures occurred. Delocalization of the electronic charge density of ethanol was greater than that of water at high temperature, which is consistent with the prior works that use proton NMR chemical shifts to describe hydrogen bonding. [ABSTRACT FROM AUTHOR]

We have investigated the electron momentum density of Co-3d electrons in LaCoO3 using X-ray Compton scattering in order to demonstrate the symmetry change of the Co(3d) electron orbital states through the spin-state transition. The electron momentum density reconstructed from the Compton profiles indicates the symmetry change in the 3d electronorbital states between below and above 100 K, which provides the first microscopic direct evidence for the orbital symmetry change of occupied electronic state associated with the spin-state transition in LaCoO3. The reproduced electron orbital states show a covalent bond with O-2p orbitals, which is responsible for the collectiveness in the characteristics of the spin-state transition. [ABSTRACT FROM AUTHOR]

A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m|=0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m|= 0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m|=0, 2 and OSMH curve show switching behaviors of PMA. [ABSTRACT FROM AUTHOR]

A compound refractive lens made of nickel and designed for focusing high-energy synchrotron X-rays is presented. The lens consists of 600 parabolic grooves and focuses X-rays in one plane only (planar lens). The lenses made and investigated by us earlier exhibited low transmission and irregularities in the focused beam profile. Since then, improvements in lens manufacturing technology have been made. The present lens gives an almost Gaussian profile and produces four times higher intensity at its maximum compared with the intensity of primary X-ray beams of 174 keV. [ABSTRACT FROM AUTHOR]

High-energy (116 keV) synchrotron radiation X-ray fluorescence analysis has for the first time been applied to the quantitative analysis of trace heavy elements of geological samples. Calibration curves for the determination of trace heavy elements were obtained by measuring 7 reference rock samples and showed good linearity because of the high penetrating power of the high-energy X-rays. It is found that this method is suitable for rapid and nondestructive quantitative characterization of trace heavy elements in trace amount of soil samples for forensic investigation. [ABSTRACT FROM AUTHOR]

The Compton profiles of He, Ar and Xe atoms are measured using 121.7 keV synchrotron x-rays. Comparisons of the results with recent mean-field Dirac-Hartree-Fock calculations reveal that the degree of discrepancy between the experiment and theory increases as the atomic number increases although the profile of He is reproduced well by the calculation. This study underlines the importance of incorporating the effects of electron correlations into the relativistic calculations. [ABSTRACT FROM AUTHOR]