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Anomalous X-ray scattering (MAD or SAD phasing) – the X-ray wavelength may be scanned past an absorption edge [a] of an atom, which changes the scattering in a known way. By recording full sets of reflections at three different wavelengths (far below, far above and in the middle of the absorption edge) one can solve for the substructure of ...
X-ray absorption (left) and differential phase-contrast (right) image of an in-ear headphone obtained with a grating interferometer at 60kVp. Phase-contrast X-ray imaging or phase-sensitive X-ray imaging is a general term for different technical methods that use information concerning changes in the phase of an X-ray beam that passes through an object in order to create its images.
Natural color X-ray photogram of a wine scene. Note the edges of hollow cylinders as compared to the solid candle. William Coolidge explains medical imaging and X-rays.. An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays.
X-ray emission spectroscopy (XES) is a form of X-ray spectroscopy in which a core electron is excited by an incident X-ray photon and then this excited state decays by emitting an X-ray photon to fill the core hole. The energy of the emitted photon is the energy difference between the involved electronic levels.
An X-ray spectrograph consists of a high voltage power supply (50 kV or 100 kV), a broad band X-ray tube, usually with a tungsten anode and a beryllium window, a specimen holder, an analyzing crystal, a goniometer, and an X-ray detector device. These are arranged as shown in Fig. 1.
X-ray photoelectron spectroscopy (XPS) is a surface-sensitive quantitative spectroscopic technique that measures the very topmost 200 atoms, 0.01 um, 10 nm of any surface. It belongs to the family of photoemission spectroscopies in which electron population spectra are obtained by irradiating a material with a beam of X-rays .
X-ray fluorescence (XRF) is the emission of characteristic "secondary" (or fluorescent) X-rays from a material that has been excited by being bombarded with high-energy X-rays or gamma rays.
Dual-energy X-ray absorptiometry (DXA, or DEXA [1]) is a means of measuring bone mineral density (BMD) with spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted, the bone mineral density (BMD) can be determined from the absorption of each beam by bone. Dual ...