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Page "Photomultiplier" ¶ 28
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electron and multiplier
These electrons are then directed into an electron multiplier for analysis.
These electrons are directed by the focusing electrode toward the electron multiplier, where electrons are multiplied by the process of secondary emission.
* Electron Multiplier – simulation of an electron multiplier tube
Farnsworth quickly made improvements to the device, among them introducing an electron multiplier made of nickel and deploying a " longitudinal magnetic field " in order to sharply focus the electron image.
The introduction of a multipactor in October 1933 and a multi-dynode " electron multiplier " in 1937 made Farnsworth's image dissector the first practical version of a fully electronic imaging device for television.
The remaining electrons are then deflected back into the anode, captured by a special grid, or deflected back into an electron multiplier.
An image orthicon camera can take television pictures by candlelight because of the more ordered light-sensitive area and the presence of an electron multiplier at the base of the tube, which operated as a high-efficiency amplifier.
An image orthicon consists of three parts: a photocathode with an image store (" target "), a scanner that reads this image ( an electron gun ), and a multistage electron multiplier.
A sharply focused beam of electrons ( a cathode ray ) is generated by the electron gun at ground potential and accelerated by the anode ( the first dynode of the electron multiplier ) around the gun at a high positive voltage ( approx.
These reflected electrons return down the cathode ray tube toward the first dynode of the electron multiplier surrounding the electron gun which is at high potential.
Additional amplification is also performed via secondary emission in the electron multiplier which consists of a stack of charged dynodes ( pinwheel-like disks surrounding the electron gun ) in progressively higher potentials.
Overall, the amplification at the image front and at the electron multiplier, plus the wise use of secondary emission wherever possible make the Image Orthicon an excellent camera tube, with a typical illumination on photocathode for maximum signal output of 0. 01ft-c ( 0. 1lx ).
These secondary ions are then collected by ion lenses ( 5 ) and filtered according to atomic mass ( 6 ), then projected onto an electron multiplier ( 7, top ), Faraday cup ( 7, bottom ), or CCD screen ( 8 ).
With an electron multiplier an impact of a single ion starts off an electron cascade, resulting in a pulse of 10 < sup > 8 </ sup > electrons which is recorded directly.
A microchannel plate detector is similar to an electron multiplier, with lower amplification factor but with the advantage of laterally-resolved detection.
The newly formed " product ions " flow into the mass spectrometer chamber, which contains a second quadrupole mass filter, and an electron multiplier detector, which are used to separate the ions by their mass-to-charge ratios, m / z, and measure the count rates of the ions in the desired m / z range.
Continuous dynode electron multiplier
An electron multiplier is a vacuum-tube structure that multiplies incident charges.

electron and consists
It consists of a dense core called the atomic nucleus surrounded by a space called the electron cloud.
The nucleus is made up of positively charged protons and neutral neutrons, while the electron cloud consists of negatively-charged electrons which orbit the nucleus to balance out the positive charge of the protons.
The simplest kind found in the electron transfer chain consists of two iron atoms joined by two atoms of inorganic sulfur ; these are called clusters.
Beta-minus ( β −) radiation consists of an energetic electron.
The classic onium is positronium, which consists of an electron and a positron bound together as a long-lived metastable state.
Before the scattering event, the electron is treated as sufficiently close to being at rest that its total energy consists entirely of the mass-energy equivalence of its rest mass:
As an example, a Daniell cell consists of a zinc anode ( an electron collector ), which dissolves into a zinc sulfate solution, the dissolving zinc leaving behind its electrons in the electrode according to the oxidation reaction ( s
The electron transport chain consists of a spatially separated series of redox reactions in which electrons are transferred from a donor molecule to an acceptor molecule.
It consists of one outer-sphere electron transfer between substances of the same atomic structure likewise to Marcus ’ s studies between bivalent and trivalent iron ions.
This system consists of an electron gun and an MCP equipped with a fluorescent screen opposite to the electron gun.
Cytochrome c < sub > 1 </ sub > is a subunit of the electron transport chain protein Ubiquinol Cytochrome c Reductase ( UQCR, Complex III or Cytochrome bc1 complex ), which consists of the products of one mitochondrially encoded gene, MTCYTB ( mitochondrial cytochrome b ) and ten nuclear genes: UQCRC1, UQCRC2, Cytochrome c1, UQCRFS1 ( Rieske protein ), UQCRB, UQCRQ (" 11kDa protein "), UQCRH ( cyt c1 Hinge protein ), Rieske Protein presequence, " cyt.
An ion gun consists of a cylinder where gas enters from one end face, undergoes electron bombardment from the side walls, and is subjected to an extraction voltage from the other end face.
Neutral hydrogen consists of a single proton orbited by a single electron.
If we neglect the small proportion of deuterium and tritium which may be present, each hydrogen atom consists of one proton and one electron.
This is by analogy with positronium, which also consists of a particle and its antiparticle ( an electron and positron in the case of positronium ).
Since the apical bonding of a pentacoordinate typical ( group 1, 2, 13-18 ) element compound consists of a 3-center-4-electron bond, in which the electron density is localized on two apical substituents, an arrangement in which electronegative substituents occupy apical positions is more stable.
When the primary beam consists of accelerated electrons, the probe is termed an electron microprobe, when the primary beam consists of accelerated ions, the term Ion Microprobe is used.
Each telescope consists of a spherical mirror with a Mo-Si layered synthetic microstructure ( LSM ) or Multilayer coating, a curved profile microchannel plate detector located at the telescope's prime focus, a UV background-rejecting filter, electron rejecting magnets at the telescope aperture, and image processing readout electronics.

electron and number
The approximate equation is Af, where N is the number of Af with electron line-density greater than or equal to Af, and Q is proportional to the mass of the meteorite.
The number of electrons in each element's electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior.
An atom containing an equal number of protons and electrons is electrically neutral, otherwise it has a positive charge if there are fewer electrons ( electron deficiency ) or negative charge if there are more electrons ( electron excess ).
The quantum number n first appeared in the Bohr model where it determines the radius of each circular electron orbit.
The principal quantum number, n, describes the energy of the electron and is always a positive integer.
The azimuthal quantum number,, describes the orbital angular momentum of each electron and is a non-negative integer.
The magnetic quantum number,, describes the magnetic moment of an electron in an arbitrary direction, and is also always an integer.
The copper is removed by bonding to a ligand, which is a large molecule consisting of a number of smaller groups, each possessing a lone electron pair.
The standard presentation of the chemical elements is in the periodic table, which orders elements by atomic number and groups them by electron configuration.
In practice, the transfer of electrons will always change the oxidation number, but there are many reactions that are classed as " redox " even though no electron transfer occurs ( such as those involving covalent bonds ).
The number of electrons donated or accepted in a redox reaction can be predicted from electron configuration of the reactant element.
Compression of the electron gas increases the number of electrons in a given volume and raises the maximum energy level in the occupied band.
The number of bonds depends on the size, charge, and electron configuration of the metal ion and the ligands.
By inserting the energetic definitions of the ionization potential and electron affinity into the Mulliken electronegativity, it is possible to show that the Mulliken chemical potential is a finite difference approximation of the electronic energy with respect to the number of electrons., i. e.,
Taking into account the spin of the electron adds a last quantum number, the projection of the electron's spin angular momentum along the z-axis, which can take on two values.
where α is the fine-structure constant and j is a number which is the total angular momentum eigenvalue ; that is, depending on the direction of the electron spin.
The resulting solution quantum states now must be classified by the total angular momentum number j ( arising through the coupling between electron spin and orbital angular momentum ).
The number of these ions is proportional to the gaseous molecule density multiplied by the electron current emitted from the filament, and these ions pour into the collector to form an ion current.
These numerical co-incidences refer to such quantities as the ratio of the age of the universe to the atomic unit of time, the number of electrons in the universe, and the difference in strengths between gravity and the electric force for the electron and proton.
Starting in the late 1960s, several experiments found that the number of electron neutrinos arriving from the Sun was between one third and one half the number predicted by the Standard Solar Model.
The pure number we call the fine structure constant and denote by α is a combination of the electron charge, e, the speed of light, c, and Planck's constant, h. At first we might be tempted to think that a world in which the speed of light was slower would be a different world.
Increasing the intensity of the light beam increases the number of photons in the light beam, and thus increases the number of electrons excited, but does not increase the energy that each electron possesses.

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