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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.
Small-angle X-ray scattering (SAXS) is a small-angle scattering technique by which nanoscale density differences in a sample can be quantified. This means that it can determine nanoparticle size distributions, resolve the size and shape of (monodisperse) macromolecules , determine pore sizes, characteristic distances of partially ordered ...
The XANES energy region [3] extends between the edge region and the EXAFS region over a 50-100 eV energy range around the core level x-ray absorption threshold. Before 1980 the XANES region was wrongly assigned to different final states: a) unoccupied total density of states, or b) unoccupied molecular orbitals (kossel structure) or c) unoccupied atomic orbitals or d) low energy EXAFS ...
The main limitation of this type of CT is the bulk and inertia of the equipment (X-ray tube assembly and detector array on the opposite side of the circle) which limits the speed at which the equipment can spin. Some designs use two X-ray sources and detector arrays offset by an angle, as a technique to improve temporal resolution. [8] [9]
Cathode-ray tube. The only visible differences are the single electron gun, the uniform white phosphor coating, and the lack of a shadow mask. A cathode-ray tube ( CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. [2]
Aspect ratio (image) The aspect ratio of an image is the ratio of its width to its height. It is expressed as two numbers separated by a colon, width:height. Common aspect ratios are 1.85:1 and 2.40:1 in cinematography, 4:3 and 16:9 in television, and 3:2 in still photography .
A gamma ray, also known as gamma radiation (symbol. γ. ), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays. With frequencies above 30 exahertz ( 3 × 1019 Hz) and wavelengths less than 10 ...
A radiologist interpreting magnetic resonance imaging. Dr. Macintyre's X-Ray Film (1896) Radiology ( / ˌreɪdɪˈɒlədʒi / rey-dee-ol-uh-jee) is the medical specialty that uses medical imaging to diagnose diseases and guide their treatment, within the bodies of humans and other animals. It began with radiography (which is why its name has a ...