X-ray diffraction from crystal surfaces at grazing angles gives rise to X-ray standing waves above and below the surface. Expressions are derived for the fluorescence observed from atoms located on or in a crystal as a result of excitation by the grazing-angle X-ray standing waves. In addition to the dependence of the fluorescence on the position of the atom with regard to the crystal plane tha...

A combination of x-ray fluorescence and image processing has been shown to recover text characters written in iron gall ink on parchment, even when obscured by gold paint. Several leaves of the Archimedes Palimpsest were imaged using rapid-scan, x-ray fluorescence imaging performed at the Stanford Synchrotron Radiation Lightsource of the SLAC National Accelerator Laboratory. A simple linear sho...

The main principles and some applications of Bragg-Fresnel multilayer optics are described. An elliptical Bragg-Fresnel multilayer lens (BFML), designed and fabricated in the IMT RAS has been used for Zdimensional focusing of the white X-ray synchrotron beam. For the beam energy of about 12 KeV the spot size checked with the knife edge method was about lpm. As an example of a successful applica...

A new technical approach to breast-tumor detection is proposed. The technique is based on fluorescence x-ray analysis, and can identify a miniature malignant tumor within the breast. The primary beam intensity needed in fluorescence x-ray analysis is on a lower order of magnitude than that used in mammography. Thus, the newly-proposed technique would enable detection of a still tiny breast canc...

In this paper we compare confocal apparatus tomography and computer tomography for medical use. Two aspects are illustrated: the process of image visualization and the dose deposition. The latter aspect is a damage factor of the object under investigation; it is why the data collection time is evaluated. Two principal tomography schemes are described and the expressions connecting the collected...

The Linac Coherent Light Source is an x-ray free-electron laser that recently demonstrated lasing in the 1.5-15 Å wavelength range. We report on luminescence measurements of a molecular nitrogen gas irradiated by ∼2  mJ, 80 fs x-ray pulses at energies of 0.83, 2.7, and 8.3 keV. These results provide a direct test of our current understanding of photoabsorption, electron dynamics, and fluorescen...

The x-ray absorption near-edge spectra (XANES) and fluorescence spectra of molecules in the ground state and optically excited states are computed using time-dependent density functional theory and time-dependent Hartree-Fock theory. The calculated XANES spectra of optically excited methanol, benzonitrile, hydrogen sulphide, and titanium tetrachloride and the fluorescence spectra of optically e...

Europium (Eu) doped ZnO microsphere based nano-sheets were synthesized through hydrothermal method. Effects of different concentrations of Europium on structural and optical properties of ZnO nano-sheets were investigated in detail. Prepared un-doped and Eu-doped ZnO samples were characterized using X-Ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron micro...