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The electron capture detector is used for detecting electron-absorbing components (high electronegativity) such as halogenated compounds in the output stream of a gas chromatograph. The ECD uses a radioactive beta particle (electron) emitter in conjunction with a so-called makeup gas flowing through the detector chamber.
Resonance electron capture [3] is also known as nondissociative EC. The compound captures an electron to form a radical anion. [4] The energy of the electrons are about 0 eV. The electrons can be created in the Electron Ionization source with moderating gas such as H 2, CH 4, i-C 4 H 10, NH 3, N 2, and Ar. [5] After the ion captures the electron, the complex formed can stabilize during ...
Charge coupled device (CCD) cameras were first applied to transmission electron microscopy in the 1980s and later became widespread. [3] [4] For use in a TEM, CCDs are typically coupled with a scintillator such as single crystal Yttrium aluminium garnet (YAG) in which electrons from the electron beam are converted to photons, which are then transferred to the sensor of the CCD via a fiber ...
He invented the electron capture detector and, using it, became the first to detect the widespread presence of chlorofluorocarbons in the atmosphere. While designing scientific instruments for NASA, he developed the Gaia hypothesis. In the 2000s, he proposed a method of climate engineering to restore carbon dioxide–consuming algae.
The theory of electron capture was first discussed by Gian-Carlo Wick in a 1934 paper, and then developed by Hideki Yukawa and others. K-electron capture was first observed by Luis Alvarez, in vanadium, 48 V, which he reported in 1937. [3] [4] [5] Alvarez went on to study electron capture in gallium (67 Ga) and other nuclides. [3] [6] [7]
A chlorine detector in the former Homestake Mine near Lead, South Dakota, containing 520 short tons (470 metric tons) of fluid, was the first to detect the solar neutrinos, and made the first measurement of the deficit of electron neutrinos from the sun (see Solar neutrino problem).
4D scanning transmission electron microscopy (4D STEM) is a subset of scanning transmission electron microscopy (STEM) which utilizes a pixelated electron detector to capture a convergent beam electron diffraction (CBED) pattern at each scan location. This technique captures a 2 dimensional reciprocal space image associated with each scan point ...
In the electron capture mode, the PDD is a selective detector for monitoring high electron affinity compounds such as freons, chlorinated pesticides, and other halogen compounds. For this type of compound, the minimum detectable quantity (MDQ) is at the femtogram ( 10 − 15 g {\displaystyle 10^{-15}\,\mathrm {g} } ) or picogram ( 10 − 12 g ...