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An X-ray generator generally contains an X-ray tube to produce the X-rays. Possibly, radioisotopes can also be used to generate X-rays. [1]An X-ray tube is a simple vacuum tube that contains a cathode, which directs a stream of electrons into a vacuum, and an anode, which collects the electrons and is made of tungsten to evacuate the heat generated by the collision.
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 ...
Xeroradiography is a type of X-ray imaging in which a picture of the body is recorded on paper rather than on film. In this technique, a plate of selenium, which rests on a thin layer of aluminium oxide, is charged uniformly by passing it in front of a scorotron. [1] The process was developed by engineer Dr. Robert C. McMaster in 1950. [2]
X-ray generators produce X-rays by applying a high voltage between the cathode and the anode of an X-ray tube and in heating the tube filament to start the electron emission. The electrons are then accelerated in the resulting electric potential and collide with the anode, which is usually made of Tungsten .
Many microfocus X-ray sources operate with focus spots in the range 5-20 μm, but in the extreme cases spots smaller than 1 μm may be produced. [citation needed] The major drawback of solid-anode microfocus X-ray tubes is their very low operating power. To avoid melting the anode, the electron-beam power density must be below a maximum value.
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.
The energy and penetrating ability of the X-rays produced by an X-ray tube increases with the voltage on the tube. External beam radiotherapy began around the turn of the 20th century with ordinary diagnostic X-ray tubes, which used voltages below 150 kV. [6]
Energy-dispersive X-ray spectroscopy (EDS, EDX, EDXS or XEDS), sometimes called energy dispersive X-ray analysis (EDXA or EDAX) or energy dispersive X-ray microanalysis (EDXMA), is an analytical technique used for the elemental analysis or chemical characterization of a sample. It relies on an interaction of some source of X-ray excitation and ...