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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

The basic form of ionization in mass spectrometry is electron ionization (EI), where an electron beam ... collides with the molecules of the sample to transform them into positively charged ions.  4, record 1, English, - electron%20ionization

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Le principe de l'ionisation électronique consiste à accélérer des électrons émis par un filament chauffé. Ceux-ci rentrent en collision avec les molécules. Si l'énergie cinétique fournie aux électrons est importante, quelques dizaines d'eV [électronvolts], alors un électron est arraché à la molécule au cours de la collision et un ion positif est formé.  1, record 1, French, - ionisation%20%C3%A9lectronique

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Record 2,  Textual support,  English

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 OBS

OMU  2, record 2, French, - ionisation%20par%20choc

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 CONT

Impact ionization and avalanche multiplication of electrons and holes in the presence of a large electric field. The excess energy is given off to generate an electron-hole pair through a band-to-band transition. This generation process causes avalanche multiplication in semiconductor diodes under high reverse bias : As one carrier accelerates in the electric field it gains energy. The kinetic energy is given off to an electron in the valence band, thereby creating an electron-hole pair. The resulting two electrons can create two more electrons which generate four more causing an avalanche multiplication effect. Electrons as well as holes contribute to avalanche multiplication.  1, record 3, English, - avalanche%20multiplication%20effect

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 DEF

Effet qui se manifeste par l'augmentation rapide des porteurs de charge lorsqu'un champ électrique intense agit sur un semi-conducteur.  1, record 3, French, - effet%20d%27avalanche

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

Photon excitation : X-ray emission induced by the impact of charged particles other than electrons, for example alpha particles, was discovered by Chadwick in 1912. High energy(1. 5 MeV) photons are associated with large cross-sections for ionization and very low backgrounds, two ideal conditions for very low detection limits that effectively reach 10[ upperscript-11]-10[ upperscript-12](g) for elements with Z > 15. On account of this high absolute sensitivity, photon excitation is used with Si(Li) detectors in many applications dealing with the simultaneous determination of trace elements in water, serum, blood and tissues.  1, record 4, English, - photon%20excitation

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 CONT

Fluorescence : Luminescence produite à partir d'un état singulet, très bref, excité électroniquement. Cette luminescence se produit après disparition de la source d'excitation (excitation photonique, souvent UV).  2, record 4, French, - excitation%20photonique

Record number: 4, Textual support number: 2 CONT

La thérapeutique photo-dynamique dans le cancer bronchique précoce. [...] Sous l'action d'une lumière adaptée à la molécule, ce photo-sensibilisateur devient actif et toxique. L'excitation photonique permet de transférer l'énergie vers l'oxygène ambiant qui prend alors la forme d'oxygène singulé. Cet oxygène est extrêmement réactif et toxique et oxyde tous les constituants tissulaires situés à son contact.  3, record 4, French, - excitation%20photonique

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

One important aspect of the physics of stars is the way in which radiation generated inside is transported out-it can alter the temperature and pressure of the star, and affect the distribution of mass within. At the same time, radiation transport affects the excitation and ionization of atoms in the star, which in turn affects the way in which radiation is transported. Ionization also makes extra electrons available, and so radiation transport, and the details of photo-excitation, ultimately has an impact on the equation of state of the star-the relationship of temperature, density and pressure.  2, record 5, English, - radiation%20transport

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 DEF

Propagation d'une multitude d'objets physiques, ondes, particules dans la matière qui se transforme sous d'autres formes.  1, record 5, French, - transfert%20de%20radiation

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Record 6,  Textual support,  English

Record number: 6, 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 6, English, - electron%20impact%20detector

Record 6,  Textual support,  French

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Record 8,  Textual support,  English

Record number: 8, Textual support number: 1 OBS

... ion sources fall into three major categories :... for positive-ion generation,... for negative ion generation, and a highly specialized type of source designed to produce a polarized ion beam.... The principal methods of positive-ion formation are electron impact, surface ionization, spark discharge... [in this Patter technique] a spark is induced between two electrodes, one of which, at least, contains the element to be ionized... the spark consists of a high density, high-temperature plasma from which ions can be extracted.  2, record 8, English, - spark%20source

Record 8,  Textual support,  French

Record number: 8, Textual support number: 1 CONT

L'ionisation par étincelles est utilisée pour l'analyse élémentaire des solides minéraux conducteurs de l'électricité ou rendus tels. Avec le matériau dont on veut connaître la composition, on réalise [...] deux électrodes [...] reliées, sous vide, aux bornes d'un générateur haute fréquence [...] et haute tension [...] Lorsque la distance inter-électrodes [...] diminue, des claquages apparaissent; ils produisent [...] un grand nombre d'ions mono et polychargés [...] Ces ions sont accélérés et dirigés vers un spectromètre; [...]  1, record 8, French, - source%20%C3%A0%20ionisation%20par%20%C3%A9tincelles

Record 8,  Textual support,  Spanish

Record 9,  Textual support,  English

Record number: 9, Textual support number: 1 CONT

The principal methods of positive-ion formation are electron impact, surface ionization, spark discharge.... Surface ionization. Atoms possessing low ionization potentials can be ionized by allowing them to strike a heated surface having a high work function... the atom will be thermally desorbed as a positive ion.  1, record 9, English, - surface%20ionization

Record 9,  Textual support,  French

Record number: 9, Textual support number: 1 CONT

Source à ionisation de surface (ou thermo-ionisation) (...) On dirige sous vide, vers une surface métallique chauffée (...) la vapeur atomique d'un élément (...) La faible dispersion énergétique des ions produits (...) permet leur analyse par un simple lecteur magnétique.  1, record 9, French, - ionisation%20de%20surface

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Ce procédé fournit des courants d'ions intenses (...) et stables pour tous les éléments de faible potentiel d'ionisation (alcalins, ternes, rares, etc.).  1, record 9, French, - ionisation%20de%20surface

Record 9,  Textual support,  Spanish

Record 10,  Textual support,  English

Record number: 10, Textual support number: 1 CONT

Methods of ion production. For analysis of organic compounds the principal methods are electron impact, chemical ionization, field ionization and field desorption. Electron impact. When a gaseous sample of a molecular compound is ionized with a beam of energetic... electrons, part of the energy is transferred to the ion formed by the collision....  1, record 10, English, - electron%20impact

Record number: 10, Textual support number: 1 OBS

Examples of ion sources utilizing this concept are the duoplasmatron and the Penning ion source.  1, record 10, English, - electron%20impact

Record 10,  Textual support,  French

Record number: 10, Textual support number: 1 OBS

Ionisation par bombardement électronique (...) L'échantillon, en phase vapeur et sous faible pression (...) est bombardé par un faisceau d'électrons (...) émis par un filament de tungstène ou de rhénium (...) La plus grande partie des ions formés sont chargés positivement (...) La notation M[exposant]+. signifie que l'on obtient un ion moléculaire radicalaire (...) à partir de la molécule M.  1, record 10, French, - bombardement%20%C3%A9lectronique

Record 10,  Textual support,  Spanish