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UNPAIRED ELECTRON [7 records]
Record 1 - internal organization data 2025-06-27
Record 1, English
Record 1, Subject field(s)
- Chemistry
Record 1, Main entry term, English
- radical
1, record 1, English, radical
correct, noun
Record 1, Abbreviations, English
Record 1, Synonyms, English
- free radical 2, record 1, English, free%20radical
correct, noun
Record 1, Textual support, English
Record number: 1, Textual support number: 1 DEF
A molecular entity... possessing an unpaired electron. 3, record 1, English, - radical
Record 1, French
Record 1, Domaine(s)
- Chimie
Record 1, Main entry term, French
- radical
1, record 1, French, radical
correct, masculine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
- radical libre 2, record 1, French, radical%20libre
correct, masculine noun
Record 1, Textual support, French
Record number: 1, Textual support number: 1 DEF
Entité moléculaire [...] possédant un électron [...] non apparié. 1, record 1, French, - radical
Record 1, Spanish
Record 1, Campo(s) temático(s)
- Química
Record 1, Main entry term, Spanish
- radical libre
1, record 1, Spanish, radical%20libre
correct, masculine noun
Record 1, Abbreviations, Spanish
Record 1, Synonyms, Spanish
Record 1, Textual support, Spanish
Record number: 1, Textual support number: 1 DEF
Molécula altamente reactiva e inestable, debido a que le faltan o sobran electrones y busca tomarlos o liberarlos para lograr mayor estabilidad, pero que en este proceso puede causar un significativo daño a las moléculas contenidas en las células y por tanto, a las células mismas. 2, record 1, Spanish, - radical%20libre
Record 2 - internal organization data 2011-06-07
Record 2, English
Record 2, Subject field(s)
- Electromagnetic Radiation
Record 2, Main entry term, English
- Overhauser effect
1, record 2, English, Overhauser%20effect
correct
Record 2, Abbreviations, English
Record 2, Synonyms, English
Record 2, Textual support, English
Record number: 2, Textual support number: 1 DEF
The effect whereby, if a radio frequency field is applied to a substance in an external magnetic field, whose nuclei have spin ½ and which has unpaired electrons, at the electron spin resonance frequency, the resulting polarization of the nuclei is as great as if the nuclei had the much larger electron magnetic moment. 1, record 2, English, - Overhauser%20effect
Record 2, French
Record 2, Domaine(s)
- Rayonnements électromagnétiques
Record 2, Main entry term, French
- effet Overhauser
1, record 2, French, effet%20Overhauser
correct, masculine noun
Record 2, Abbreviations, French
Record 2, Synonyms, French
- relaxation dipolaire croisée 2, record 2, French, relaxation%20dipolaire%20crois%C3%A9e
correct, feminine noun
Record 2, Textual support, French
Record number: 2, Textual support number: 1 DEF
Effet conduisant à une polarisation dynamique des spins nucléaires, observé dans un métal ou un semi-conducteur soumis à un champ magnétique, lorsque la polarisation des spins électroniques est détruite par application d’un champ hyperfréquence. 3, record 2, French, - effet%20Overhauser
Record number: 2, Textual support number: 1 CONT
Considérons deux spins homonucléaires proches dans l’espace, chacun d’eux exerce sur l’autre un champ magnétique local. Ce phénomène est plus spécifiquement appelé relaxation dipolaire croisée ou effet Overhauser. Le système de spins est décrit par quatre niveaux d’énergie. 4, record 2, French, - effet%20Overhauser
Record number: 2, Textual support number: 1 OBS
L’effet se traduit par l’apparition d’une polarisation nucléaire importante due au couplage entre spins électroniques et spins nucléaires. 3, record 2, French, - effet%20Overhauser
Record number: 2, Textual support number: 2 OBS
La relaxation dipolaire croisée est à l’origine du NOE [effet Overhauser nucléaire]. 5, record 2, French, - effet%20Overhauser
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 2011-04-05
Record 3, English
Record 3, Subject field(s)
- Electromagnetic Radiation
Record 3, Main entry term, English
- unpaired electron relaxation
1, record 3, English, unpaired%20electron%20relaxation
correct
Record 3, Abbreviations, English
Record 3, Synonyms, English
Record 3, French
Record 3, Domaine(s)
- Rayonnements électromagnétiques
Record 3, Main entry term, French
- relaxation par des électrons non appariés
1, record 3, French, relaxation%20par%20des%20%C3%A9lectrons%20non%20appari%C3%A9s
correct, feminine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
Record 3, Textual support, French
Record 3, Spanish
Record 3, Textual support, Spanish
Record 4 - internal organization data 2011-02-03
Record 4, English
Record 4, Subject field(s)
- Chemistry
- Climate Change
Universal entry(ies) Record 4
Record 4, Main entry term, English
- hydroxyl
1, record 4, English, hydroxyl
correct
Record 4, Abbreviations, English
Record 4, Synonyms, English
- hydridooxygen(·) 2, record 4, English, hydridooxygen%28%26%23183%3B%29
correct, see observation
- hydroxyl radical 3, record 4, English, hydroxyl%20radical
correct
- HO· radical 2, record 4, English, HO%26%23183%3B%20radical
correct, see observation
- oxidanyl 2, record 4, English, oxidanyl
former designation, avoid
- free hydroxyl radical 4, record 4, English, free%20hydroxyl%20radical
former designation, avoid, see observation
- OH· radical 5, record 4, English, OH%26%23183%3B%20radical
former designation, avoid
- OH· hydroxyl radical 4, record 4, English, OH%26%23183%3B%20hydroxyl%20radical
former designation, avoid
Record 4, Textual support, English
Record number: 4, Textual support number: 1 OBS
hydroxyls : Group composed of one oxygen atom, one hydrogen atom, and one unpaired electron, HO·. 2, record 4, English, - hydroxyl
Record number: 4, Textual support number: 2 OBS
Hydroxyl radicals (HO·) are important sinks for ozone; they may be taken up by methane and carbon monoxide with which they also react. 6, record 4, English, - hydroxyl
Record number: 4, Textual support number: 3 OBS
hydridooxygen(·): pronounced "hydridooxygen dot"; form recommended by the IUPAC (International Union of Pure and Applied Chemistry). 2, record 4, English, - hydroxyl
Record number: 4, Textual support number: 4 OBS
HO· radical: descriptive name. 2, record 4, English, - hydroxyl
Record number: 4, Textual support number: 5 OBS
free radical: obsolete term; the term "radical" is recommended instead. 2, record 4, English, - hydroxyl
Record 4, French
Record 4, Domaine(s)
- Chimie
- Changements climatiques
Entrée(s) universelle(s) Record 4
Record 4, Main entry term, French
- hydroxyle
1, record 4, French, hydroxyle
correct, masculine noun
Record 4, Abbreviations, French
Record 4, Synonyms, French
- hydrurooxygène(·) 2, record 4, French, hydrurooxyg%C3%A8ne%28%26%23183%3B%29
correct, see observation, masculine noun
- radical hydroxyle 3, record 4, French, radical%20hydroxyle
correct, masculine noun
- radical HO· 2, record 4, French, radical%20HO%26%23183%3B
correct, see observation, masculine noun
- oxidanyle 2, record 4, French, oxidanyle
former designation, avoid, masculine noun
- oxhydryle 4, record 4, French, oxhydryle
former designation, avoid, masculine noun
- radical libre hydroxyle 5, record 4, French, radical%20libre%20hydroxyle
former designation, avoid, masculine noun
- radical OH· 6, record 4, French, radical%20OH%26%23183%3B
former designation, avoid, masculine noun
- radical libre hydrogéné 5, record 4, French, radical%20libre%20hydrog%C3%A9n%C3%A9
former designation, avoid, masculine noun
- radical hydroxyle OH· 5, record 4, French, radical%20hydroxyle%20OH%26%23183%3B
former designation, avoid, masculine noun
Record 4, Textual support, French
Record number: 4, Textual support number: 1 OBS
hydroxyles : Groupe composé d'un atome d'oxygène, d'un atome d'hydrogène et d'un électron non apparié, HO· ou HO(·). 2, record 4, French, - hydroxyle
Record number: 4, Textual support number: 1 CONT
Mis en présence de l'acide chlorhydrique, les radicaux hydroxyles libèrent du chlore atomique qui détruit l'ozone selon la réaction HO· + HC1 = H20 + C1. 7, record 4, French, - hydroxyle
Record number: 4, Textual support number: 2 OBS
La présence du radical hydroxyle est fondamentale dans le phénomène d'effet de serre. Ce radical constitue un puits très important pour le monoxyde de carbone et le méthane. Il nettoie littéralement l'atmosphère de plusieurs gaz à effet radiatif. Sa disparition aurait pour conséquence des augmentations marquées de la concentration des gaz à effet de serre. 8, record 4, French, - hydroxyle
Record number: 4, Textual support number: 3 OBS
hydrurooxygène(·) : prononcé «hydrurooxygène point»; forme recommandée par l'UICPA (Union internationale de chimie pure et appliquée). 2, record 4, French, - hydroxyle
Record number: 4, Textual support number: 4 OBS
radical HO· : nom descriptif. Les points sont en exposant HO· lorsque le nom du radical se termine par «yle», par exemple «hydroxyle». Ce sont des points centrés entre parenthèses après les noms qui n'ont pas le suffixe «-yle». Par exemple : hydruroxygène(·) ou HO(·). 2, record 4, French, - hydroxyle
Record number: 4, Textual support number: 5 OBS
radical libre : Ce nom est obsolète; il est remplacé par «radical», sans autre mention. 2, record 4, French, - hydroxyle
Record 4, Spanish
Record 4, Campo(s) temático(s)
- Química
- Cambio climático
Entrada(s) universal(es) Record 4
Record 4, Main entry term, Spanish
- hidroxilo
1, record 4, Spanish, hidroxilo
masculine noun
Record 4, Abbreviations, Spanish
Record 4, Synonyms, Spanish
Record 4, Textual support, Spanish
Record 5 - internal organization data 1998-02-18
Record 5, English
Record 5, Subject field(s)
- Chemistry
Record 5, Main entry term, English
- spin label
1, record 5, English, spin%20label
correct
Record 5, Abbreviations, English
Record 5, Synonyms, English
Record 5, Textual support, English
Record number: 5, Textual support number: 1 DEF
A molecule which contains an atom or group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance(ESR) spectroscopy and can be bonded to another molecule. 2, record 5, English, - spin%20label
Record 5, French
Record 5, Domaine(s)
- Chimie
Record 5, Main entry term, French
- marqueur de spin
1, record 5, French, marqueur%20de%20spin
correct, masculine noun
Record 5, Abbreviations, French
Record 5, Synonyms, French
- marqueur spin 2, record 5, French, marqueur%20spin
masculine noun
Record 5, Textual support, French
Record number: 5, Textual support number: 1 DEF
Groupe paramagnétique stable [...] fixé sur une partie d'une autre entité moléculaire dont on veut étudier l'environnement microscopique. Le spectre de résonance paramagnétique électronique est alors caractéristique de cet environnement. 3, record 5, French, - marqueur%20de%20spin
Record number: 5, Textual support number: 1 OBS
Le terme "marqueur de spin" a été relevé dans le "Glossaire d'équivalents français d'expressions ou de termes principalement anglo-saxons couramment utilisés dans le domaine de la chimie", proposé par la "Commission de Terminologie Chimique agissant sous les auspices de la Délégation Générale à la Langue Française", et paru dans "L'Actualité chimique" de mai-juin 1992, p. 269-271. 4, record 5, French, - marqueur%20de%20spin
Record number: 5, Textual support number: 2 OBS
Le terme "marqueur spin" a été relevé dans la base Pascal. 2, record 5, French, - marqueur%20de%20spin
Record 5, Spanish
Record 5, Textual support, Spanish
Record 6 - internal organization data 1996-11-21
Record 6, English
Record 6, Subject field(s)
- Chemistry
Record 6, Main entry term, English
- radical centre
1, record 6, English, radical%20centre
correct
Record 6, Abbreviations, English
Record 6, Synonyms, English
Record 6, Textual support, English
Record number: 6, Textual support number: 1 DEF
The atom(or group of atoms) in a polyatomic radical on which an unpaired electron is largely localized. 1, record 6, English, - radical%20centre
Record 6, Key term(s)
- radical center
Record 6, French
Record 6, Domaine(s)
- Chimie
Record 6, Main entry term, French
- centre radicalaire
1, record 6, French, centre%20radicalaire
correct, masculine noun
Record 6, Abbreviations, French
Record 6, Synonyms, French
Record 6, Textual support, French
Record number: 6, Textual support number: 1 DEF
Atome ou groupe d'atomes d'un radical polyatomique sur lequel un électron célibataire est en grande partie localisé. 1, record 6, French, - centre%20radicalaire
Record number: 6, Textual support number: 1 OBS
La fixation d'un atome monovalent à un centre radicalaire conduit à une molécule pouvant être décrite par une formule de Lewis où chaque atome possède une valence normale stable. 1, record 6, French, - centre%20radicalaire
Record 6, Spanish
Record 6, Textual support, Spanish
Record 7 - internal organization data 1989-11-27
Record 7, English
Record 7, Subject field(s)
- Chemical Elements and Compounds
- Air Pollution
Record 7, Main entry term, English
- unpaired electron
1, record 7, English, unpaired%20electron
correct
Record 7, Abbreviations, English
Record 7, Synonyms, English
Record 7, Textual support, English
Record number: 7, Textual support number: 1 CONT
electron paramagnetic resonance. A phenomenon observed when paramagnetic substances containing unpaired electrons are subjected to high magnetic fields and microwave radiation. 1, record 7, English, - unpaired%20electron
Record 7, French
Record 7, Domaine(s)
- Éléments et composés chimiques
- Pollution de l'air
Record 7, Main entry term, French
- électron non apparié
1, record 7, French, %C3%A9lectron%20non%20appari%C3%A9
correct, masculine noun
Record 7, Abbreviations, French
Record 7, Synonyms, French
Record 7, Textual support, French
Record number: 7, Textual support number: 1 DEF
Électron caractéristique d'un radical libre résultant de la fragmentation photochimique d'une molécule par rupture homolytique d'une liaison chimique. 2, record 7, French, - %C3%A9lectron%20non%20appari%C3%A9
Record number: 7, Textual support number: 1 CONT
Dans la troposphère, la quasi-totalité des réactions chimiques ayant lieu dans la phase gazeuse procède d'un mécanisme radicalaire, c'est-à-dire impliquant des espèces chimiques électriquement neutres, très réactives, donc de courte durée de vie, nommées radicaux libres et caractérisées par la présence d'un (ou parfois plusieurs) électron(s) non apparié(s). 1, record 7, French, - %C3%A9lectron%20non%20appari%C3%A9
Record number: 7, Textual support number: 1 OBS
Un radical libre peut avoir, quoique rarement, plus d'un électron non apparié. 2, record 7, French, - %C3%A9lectron%20non%20appari%C3%A9
Record 7, Spanish
Record 7, Textual support, Spanish
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