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Electronic detectors

There are many types of electronic detector. The original fomi of electronic detector was the Geiger counter, but it was replaced many years ago by the proportional counter, which allows selection of radiation of a particular type or energy. Proportional counters for x-rays are filled witii a gas such as xenon, and those for... [Pg.1379]

Figure Bl.10.7. Electron impact ionization coincidence experiment. The experiment consists of a source of incident electrons, a target gas sample and two electron detectors, one for the scattered electron, the other for the ejected electron. The detectors are coimected tlirough preamplifiers to the inputs (start and stop) of a time-to-amplitiide converter (TAC). The output of the TAC goes to a pulse-height-analyser (PHA) and then to a nuiltichaimel analyser (MCA) or computer. Figure Bl.10.7. Electron impact ionization coincidence experiment. The experiment consists of a source of incident electrons, a target gas sample and two electron detectors, one for the scattered electron, the other for the ejected electron. The detectors are coimected tlirough preamplifiers to the inputs (start and stop) of a time-to-amplitiide converter (TAC). The output of the TAC goes to a pulse-height-analyser (PHA) and then to a nuiltichaimel analyser (MCA) or computer.
Figure Bl.10.11. Electron impact double ionization triple coincidence experiment. Shown are the source of electrons, target gas, tluee electron detectors, one for the scattered electron and one for each of the ejected... Figure Bl.10.11. Electron impact double ionization triple coincidence experiment. Shown are the source of electrons, target gas, tluee electron detectors, one for the scattered electron and one for each of the ejected...
Xps ndAes Instrumentation. The instmmentation required to perform xps and aes analyses is generally sophisticated and expensive (19). The need for UHV conditions in order to retain surface cleanliness for a tractable period of time was mentioned above. Beyond this requirement (and the hardware that accompanies it), the most important components of an electron spectrometer system are the source, the electron energy analyzer, and the electron detector. These will be discussed in turn below. [Pg.282]

Scintillators are also used in the detectors of CT scanners. Here an electronic detector, the photomultiplier tube, is used to produce an electrical signal from the visible and ultraviolet light photons. These imaging systems typically need fast scintillators with a high efficiency. [Pg.50]

After adequate analitical prepai ation according to standai d EPA method 608 samples were analysed gas chromatographic on a gas chromatograph 8500 Perkin Elmer, in glass and capilar columns using a capture electron detector and mass spectrometry, temperature program. [Pg.227]

X-ray data are recorded either on image plates or by electronic detectors... [Pg.377]

X-ray data are recorded either on image plates or by electronic detectors The rules for diffraction are given by Bragg s law Phase determination is the major crystallographic problem Phase information can also be obtained by Multiwavelength Anomalous Diffraction experiments... [Pg.418]

An electron gun produces and accelerates the electron beam, which is reduced in diameter (demagnified) by one or more electromagnetic electron lenses. Electromagnetic scanning coils move this small electron probe (i.e., the beam) across the specimen in a raster. Electron detectors beyond the specimen collect a signal that is used to modulate the intensity on a cathode-ray tube that is scanned in synchronism with the beam on the specimen. A schematic of the essential components in a dedicated STEM system is shown in Figure 2. [Pg.163]

Some proportional detectors are combined in the same instrument with a suitable transducer which can perform some of the functions of a controller. For example, for pneumatic systems the primary sensing element actuates a variable air jet, thus modulating an air pressure which is transmitted to a further controller or direct to the controlled device. Electric and electronic detectors such as the infrared detector include the sensing and amplifying circuits of the instrument. [Pg.327]

High-pressure pumps operating at up to 6000 psi are required to force solvent through a tightly packed HPLC column, and electronic detectors are used to monitor the appearance of material eluting from the column. Alternatively, the column can be interfaced to a mass spectrometer to determine the mass spectrum of every substance as it elutes. Figure 12.18 shows the results of HPLC analysis of a mixture of 10 fat-soluble vitamins on 5 jam silica spheres with acetonitrile as solvent. [Pg.432]

Fig. 8.23 Mossbauer emission spectra of [ Co/Co(terpy)2lX2 H20(X = C104, n = V2 X = CP, n = 5) as source material versus KrpefCNlel as absorber (which was kept at 298 K) recorded at 100 K with a convCTsion-electron detector. = C104,n = Vi. Right X = Cl, = 5 (from [53])... Fig. 8.23 Mossbauer emission spectra of [ Co/Co(terpy)2lX2 H20(X = C104, n = V2 X = CP, n = 5) as source material versus KrpefCNlel as absorber (which was kept at 298 K) recorded at 100 K with a convCTsion-electron detector. = C104,n = Vi. Right X = Cl, = 5 (from [53])...
The total contribution to the Auger electron signal is then dependent upon the attenuation length (kM) in the matrix before being inelastically scattered, and upon the transmission efficiency of the electron spectrometer as well as the efficiency of the electron detector. Calculated intensities of Auger peaks rarely give an accuracy better than 50%, and it is more reliable to adopt an approach which utilises standards, preferably obtained in the same instrument. [Pg.175]

HRSEM images of STA-7 were taken using a JEOL JSM-7000F (FE SEM). Images of silicalite-2 and zeolite A were taken on a JEOL JSM-7401F (cold-FE SEM) using the Everhart-Thomley (E-T) secondary electron detector. Samples were not coated but placed on a conductive surface. [Pg.24]

The secondary electrons emitted from the sample are collected in the sample chamber. The most common type of secondary electron detector is the scintilla-... [Pg.144]

Backscattered Electron Detectors and Applications, Amray Technical Bulletin 122-685, Amray, Bedford, Mass., 1986, pp. 89-106. [Pg.155]

Two different types of odor measurements can be performed, either analytical measurements or sensory measurements (cf. Section 7.1.4). Sensory measurements are either performed by the human nose or electronic detectors and, therefore, relate to the effects of the odor (Sneath and Clarkson, 2000 Stuetz et... [Pg.83]

Backscattered electron images, 24 76-77 Backscattered primary ions, 24 106 Back-scatter electron detectors, in fine art examination/conservation, 11 406 Backstaining, 10 303 Backus process, 4 810 Backward approach, to qualitative reliability analysis, 26 984 Backwash, 11 323... [Pg.83]

As the name implies, capillary electrophoresis is electrophoresis that is made to occur inside a piece (50 to 100 cm) of small-diameter capillary tubing, similar to the tubing used for capillary GC columns. The tubing contains the electrolyte medium, and the ends of the tube are dipped into solvent reservoirs, as is the paper in paper electrophoresis. Electrodes in these reservoirs create the potential difference across the capillary tube. An electronic detector, such as those described for HPLC (Chapter 13), is on-line and allows detection and quantitative analysis of mixture components. [Pg.328]


See other pages where Electronic detectors is mentioned: [Pg.802]    [Pg.1307]    [Pg.1313]    [Pg.1625]    [Pg.1631]    [Pg.1632]    [Pg.1632]    [Pg.1842]    [Pg.291]    [Pg.294]    [Pg.513]    [Pg.49]    [Pg.377]    [Pg.164]    [Pg.54]    [Pg.73]    [Pg.91]    [Pg.710]    [Pg.504]    [Pg.504]    [Pg.367]    [Pg.40]    [Pg.416]    [Pg.4]    [Pg.167]    [Pg.262]    [Pg.66]    [Pg.955]   
See also in sourсe #XX -- [ Pg.234 , Pg.235 ]




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BCD - Electron-capture detector

Backscattered electron detector

Basic Electrochemical Detector Electronics

Beam detectors electron bombardment

Channel plate electron multiplier detector

Chromatography electron capture detector

Concentric electron-capture detectors

Conversion-electron detector

Detection methods electron capture detector

Detector Electronics Corporation

Detector electron capture

Detector scanning electron microscopy

Detector secondary electron multiplier

Detector, atomic spectrometer electron capture

Detectors channel electron multiplier

Detectors electron multipliers

Detectors electronic leak

Detectors electronic noise

Detectors electronics

Detectors pulse discharge electron-capture

Digital Electronics for Ion Counting Detectors

Dual electron capture detector

ECD, electron capturing detector

Electrochemical detector electronic circuit

Electron Capture Detector (ECD)

Electron Capture Detector kinetic Model

Electron capture detector background current

Electron capture detector cell design

Electron capture detector constant voltage

Electron capture detector for

Electron capture detector linearity

Electron capture detector photometric

Electron capture detector pulsed constant frequency

Electron capture detector response factors

Electron capture detector standing current

Electron capture detector voltage

Electron capture detector, hydrocarbon

Electron capture detector, hydrocarbon analysis

Electron conductivity detector

Electron detector (channeltron/channelplate

Electron detectors

Electron detectors

Electron detectors coincidence methods

Electron-capture detector advantage

Electron-capture detector chemical-sensitized

Electron-capture detector constant current

Electron-capture detector environmental applications

Electron-capture detector operation

Electron-capture detector performance

Electron-capture detector response characteristics

Electron-capture detector sensitivity

Electron-capture detectors, lead analysis

Electronic area detectors

Electronic chemical detectors

Energy Resolution and Response Function of Electron Detectors

Energy resolution electron detectors

Environmental secondary electron detector

Gas chromatograph/electron capture detector

Gas chromatography electron capture detector

Gaseous secondary electron detector

Gaseous secondary electron detector GSED)

Identification electron capture detector

Ion detectors channel electron multiplier

Ionisation electron capture detector

Ionization detector electron capture

Ionization detector pulsed discharge electron capture

Micro electron-capture detector

Photodetachment-modulated electron capture detector

Post-detector electronics

Pulsed discharge electron capture detector

Radiation source, electron-capture detector

Secondary electron detectors

The Electron Capture Detector

The Electron Capture Detector (ECD)

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