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

³He detectors have higher efficiency because of high neutron absorption cross-section for thermal neutrons and higher possible fill pressures up to 4 atm.  1, record 2, English, - hellium3%20detector

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Les détecteurs à ³He sont, de loin, les plus utilisés pour les mesures neutroniques passives et actives, car ils présentent une excellente efficacité de détection tout en étant relativement insensibles aux rayonnements gamma.  2, record 2, French, - d%C3%A9tecteur%20%C3%A0%20h%C3%A9lium%203

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 CONT

Conventional experiments measure the distribution of scattered electrons following a collision but, for light atomic targets such as helium, it is also possible to obtain this information from the distribution of recoiling atoms. Design, construction and testing of components for a new electron spectrometer, incorporating a spin-polarised electron source and a position-sensitive, time-of-flight, recoil atom detector is underway.  2, record 3, English, - recoil%20atom

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 DEF

Atome mis en mouvement par suite d'une collision ou de l'éjection d'une autre particule.  1, record 3, French, - atome%20de%20recul

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 DEF

The minimum detectable leak rate that the detector is capable of detecting while the enclosure is actively being evacuated continuously under specified conditions.  1, record 4, English, - dynamic%20sensitivity%20of%20helium%20leak%20detector

Record 4,  Textual support,  French

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

Photoionization detector... consists of a chamber into which gases suitable for the discharge such as helium, argon, nitrogen, or hydrogen are introduced through [a] tube which serves as the cathode for the discharge. The ultraviolet radiation or glow discharge in the hollow cathode, maintained by a small current between the cathode and discharge anode, is sufficiently energetic to ionize components in the carrier gas effluent entering through the tube, the collecting electrode(anode) for the ions liberated within the chamber enclosed by the second cathode.  5, record 5, English, - photoionization%20detector

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 CONT

Une version commerciale de ce détecteur est apparue récemment sur le marché, il est composé d'une lampe UV [détecteur à photoionisation] scellée qui émet un rayonnement à 121,6nm (10,2 eV) à travers une fenêtre en fluorure de magnésium. Si le soluté passant dans ce détecteur a un potentiel d'ionisation inférieur à 10,2eV, il s'ionise en absorbant un photon. Les ions issus de cette photoionisation sont collectés en appliquant un potentiel positif sur une des électrodes. Le courant qui en résulte est amplifié par un électromètre identique à celui utilisé avec un détecteur à ionisation de flamme.  1, record 5, French, - d%C3%A9tecteur%20%C3%A0%20photoionisation

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 CONT

With helium as discharge and carrier gas, the detector is very sensitive to permanent gases...  1, record 6, English, - discharge

Record number: 6, Textual support number: 1 PHR

argon discharge, capillary discharge, spark discharge, visible glow discharge.  2, record 6, English, - discharge

Record number: 6, Textual support number: 2 PHR

self-sustained discharge.  2, record 6, English, - discharge

Record 6,  Textual support,  French

Record 6,  Textual support,  Spanish

Record 7,  Textual support,  English

Record number: 7, Textual support number: 1 CONT

As a means of exciting noble gases at atmospheric pressures, Lovelock developed a spark device of high sensitivity, capable of detecting as little as 10^{minus 13} mole of most organic materials. The detector consisted of a spark gap made of platinum wire sealed in a glass tube. The voltage across the 5-10 mm spark gap is measured with an electrostatic voltmeter. With pure argon subjected to an applied voltage of 2000 V to create sparks, the breakdown potential measured was logarithmically related to the concentration of vapor added to the argon.  2, record 7, English, - gas%20discharge%20detector

Record number: 7, Textual support number: 1 OBS

Karmen and Bowman developed a dc discharge detector based on a low-current electric discharge in argon or helium in the presence of a high-intensity electrostatic field... Sternberg and Poilson developed a Tesla discharge detector... Evrard, Thevelin, and Joossens described a nonradioactive, self-sustained discharge detector for the detection of permanent gases.  2, record 7, English, - gas%20discharge%20detector

Record 7,  Textual support,  French

Record 7,  Textual support,  Spanish

Record 8,  Textual support,  English

Record number: 8, 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 8, English, - electron%20impact%20detector

Record 8,  Textual support,  French

Record 8,  Textual support,  Spanish