TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

The helium ionization detector(HID) has the most widespread application in the analysis of trace amounts of permanent gases. The lowest detectable amount is 500 times less than that for the thermal conductivity detector. The helium ionization detector has been employed for the determination of nitrogen oxide at a concentration of 0. 2-5 ppb, chlorinated hydrocarbons, aldehydes, alcohols, ketones, esters, and propane, for which a linear dynamic range of six orders of concentration has been obtained.  1, record 1, English, - helium%20ionization%20detector

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Détecteurs sélectifs. [...] Nous citerons encore les détecteurs électrochimiques permettant d'obtenir des réponses sélectives pour les composés azotés, chlorés ou soufrés, et d'autres, tels que le détecteur à ionisation d'argon ou d'hélium, détectant des traces de gaz permanents, de même que le détecteur à ionisation par haute fréquence.  4, record 1, French, - d%C3%A9tecteur%20%C3%A0%20ionisation%20d%27h%C3%A9lium

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

Thermionic or Electron Impact Detector. In 1957, Ryce and Bryce described a sensitive ionization gauge based on the ionization potentials of vapors. It comprised a filament, a grid, and a plate. The potential difference between the filament and grid accelerated electrons which may ionize any gas in their path. If the grid potential is maintained at a level insufficient to ionize the helium carrier gas... no current flows in the plate circuit. If a potential difference of 18 V is maintained between the filament and the grid, compounds of lower ionization potential in the helium will be ionized and the positive ions produced will yield a cathode current, the current noted being a measure of the ion concentration. Into the modified ionizing chamber, operated at reduced pressure, a small fraction of the column effluent gas stream(less than 0. 5%) was allowed to flow into the gauge through a controlled leak. Over a 0. 02-l. 5 mm Hg pressure range, the sensitivity was approximately proportional to the pressure, and sensitivities in the range of 10[ minus superscript 12] mole were claimed.  1, record 2, English, - electron%20impact%20detector

Record 2,  Textual support,  French

Record 2,  Textual support,  Spanish