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1、International Standard Norme internationale INTERNATIONAL ORGANIZATION FOR STANDARDlZATlON.MEXjlYHAPOAHAR OPTAHkWWfR ll0 CTAH/$VTH3Al$lM.ORGANlSATlON INTERNATIONALE DE NOAMALISATION Analytical spectroscopic methods - Flame emission, atomic absorption, and atomic fluorescence - Vocabulary First editi
2、on - 1962-07-15 M6thodes danalyse par spectroscopic - emission de flamme, absorption atomique et fluorescence atomique - Vocabulaire Premihe edition - 1962-07-15 G ii UDWCDU 543.42 : 001.4 Ref. No./Rhf. no : IS0 6955-1962(E/F) i Descriptors : atomic absorption spectrometry, atomic fluorescence spect
3、rometry, flame photometry, emission spectrometry, vocabulary. Descripteurs : spectrom atomic absorption, and atomic fluorescence - Vocabulary Scope and field of application This International Standard defines specific terms for flame emission, atomic absorption and atomic fluorescence spec- troscopi
4、c analytical methods, with a view to facilitating understanding between analysts. It takes maximum account of the existing terminology, in both French and English, in order to achieve the greatest possible harmonization. In particular, it takes account of the IUPAC (International Union of Pure and A
5、pplied Chemistry) nomenclature. Reference IS0 6?86, Molecular absorption spectrometry - Vocabulary - General - Apparatus. Terms and definitions 1 General terms PRELIMINARY NOTE - The term spectroscopy”, as recommended by IUPAC, means the general study of spectra, irrespective of the method of observ
6、ation; the term “spectrometry” implies the measure- ment of the intensity of the radiation. 1.1 flame emission spectrometry (FEW : A method of determining chemical elements based on the measurement of the intensity of characteristic electromagnetic radiation emitted by atoms or molecules in a flame.
7、 1.2 atomic absorption spectrometry (AAS) : A method of determining chemical elements based on the measurement of the absorption of characteristic electromagnetic radiation by atoms in the vapour phase. 1.3 atomic fluorescence spectrometry (AFSI : A method of determining chemical elements based on t
8、he measurement of the re-emission of characteristic electromagnetic radiation by atoms, following the absorption of radiation in the vapour phase. The wavelengths of the absorbed and re-emitted radia- tion may be identical (atomic resonance fluorescence spec- trometry) or different. 1.4 atomic vapou
9、r : A vapour containing free atoms of the element to be determined (the analyte). MQthodes danalyse par spectroscopic - Emission de flamme, absorption atomique et fluorescence atomique - Vocabulaire Objet et domaine dapplication La presente Norme internationale definit cettains termes speci- frques
10、pour les methodes danalyse par spectroscopic demis- sion de flamme, dabsorption atomique et de fluorescence ato- mique, dans le but de faciliter la comprehension entre analys- tes. Elle tient le plus grand compte des termes existants, aussi bien en francais quen anglais, afin daboutir a la,meilleure
11、 harmoni- sation possible. En particulier, elle tient compte de la nomencla- ture de IUICPA (Union internationale de chimie pure et appli- q le terme ctspectrometrie) implique le mesurage de Iintensite des radiations. 1.1 spectromhtrie dbmission de flamme (SEFI : Methode de dosage delements chimique
12、s fondle sur le mesurage de Iintensite de lemission de radiations photoniques specifiques par des atomes ou des molecules dans une flamme. 1.2 spectromktrie dgbsorption atomique (SAA) : Methode de dosage delements chimiques fondee sur le mesu- rage de Iabsorption de radiations photoniques specifique
13、s par des atomes en phase vapeur. I,3 spectromhtrie de fluorescence atomique (SFAI : Methode de dosage dblements chimiques fondee sur le mesu- rage de la reemission de radiations photoniques specifiques par des atomes, consecutive a labsorption de radiations en phase vapeur. La longueur donde de la
14、radiation absorbee et celle de la radiation reemise peuvent 6tre identiques (spectrometrie de fluorescence de resonance atomique) ou differentes. 1.4 vapeur atomique :Vapeur contenant des atomes libres de 16lt5ment a doser (analyte). 1 Copyright International Organization for Standardization Provide
15、d by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/19/2007 01:49:27 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 6966-1962 (E/F) I,5 energy level : A stationary quantum state (of a free atom, ion or molecule) equal in va
16、lue to a particular internal energy, This energy is often expressed in electron volts, but should preferably be expressed in kilojoules per mole. I,6 ground state : The level of minimum internal energy (of a free atom, ion or molecule), It is conventional to assign the energy value of zero to this l
17、evel. 1.7 resonance levell) : An energy level (of an excited atom, ion or molecule) capable of reversion to the ground state by a direct electromagnetic transition (see 1 .ll I. I,6 excitation energy : The energy that must be supplied to an atom to transfer it from the ground state to a given energy
18、 level above the ground state, 1,9 resonance energy21 : The energy required to promote the transfer the atom from the ground state to a resonance level by absorption of one photon, 1.10 ionization energy : The minimum energy that must be supplied to remove an electron from an atom in the ground stat
19、e. 1,ll electronic transition : The passage of an electron of an atom, ion or molecule from an energy level El to another energy level E2. An electronic transition may be accompanied by the emission 01 absorption of a photon hv such that hv + 1 E2 - El I; it is then called “an electromagnetic transi
20、tion”; in general, it obeys certain rules called “electromagnetic selection rules”. NOTE - In the formula, h is the Planck constant and Y is the fre- quency of emitted or absorbed photon. 1.12 spectral line (of an atom131 : A very narrow band of fre- quencies of electromagnetic radiation emitted or
21、absorbed by atoms which undergo a single electromagnetic transition. This radiation is centred on a peak whose wavelength characterizes the line and which corresponds to the emission or absorption maximum. A distinction is made between lines corresponding to transition of neutral atoms (e.g. Ba I 55
22、3,5 and 577,8 nm) and ions (e.g. Ha II 455,4 nml. 11 Some authors use the following mote restricted definition of the resonance level of a particular atom : The lowest level capable of reversion to the ground state by a direct electromagnetic transition. 21 Some authors use the following, more restr
23、icted definition of resonance energy : The energy required to transfer the atom from the ground state to the resonance level defined as in the note to 1.7. 3) The term “line” has its origin in the appearance of an atomic spec- trum observed with a spectroscope, in which different wavelengths ap pear
24、 monochromatically as images of the (linear1 slit. 1.5 niveau dhergie : transition Blectronique : Passage dun Electron, dun atome, dun ion ou dune mol6cule dun niveau dbnergie El B un autre niveau d6nergie E2. Une modification Blectronique peut 6tre accompagnee de IBmission ou de Iabsorption dun pho
25、ton hv tel que hv = 1 E2 - El I; elle est alors dite (transition photonique); elle ob6it en g atomiseur : Dispositif permet- tant Iatomisation. 2.2.5 overall efficiency of atomization : The ratio of the mass of analyte converted into free atoms in the atomizer to the mass of analyte entering the dis
26、persion device. 2.2.5 rendement global datomisation : Rapport du debit massique d fuel-lean flame : A flame obtained using an excess of oxidant. 2.3.6 reducing flame; fuel-rich flame : A flame obtained using an excess of fuel, 2.3.7 separated flame : A flame in which the secondary- combustion zone i
27、s separated from the primary-combustion zone. 2.3.8 long-tube device (in atomic absorption) : A device in which the flame is artificially extended to make the direction of the burnt-gas flow coincide with the direction of the incident beam of radiation. 2.3.9 laminar flame : A flame in which the bur
28、nt-gas flow is approximately parallel; the cross-section of the flame can have any shape. 2.3.10 turbulent flame : A flame in which the burnt-gas flow takes place in an irregular pattern. 2.3.11 premix burner : A burner in which the fuel, the oxi- dant and the aerosol are mixed before reaching the f
29、lame. This burner generally produces a laminar flame. 2.2.9 rendement de dispersion (de lechantillon) : Rapport du debit massique delement a doser entrant dans la source datomisation au debit massique dblement a doser entrant dans le dispositif de dispersion. 2.3.1 flamme : Debit continu de melange
30、de gaz chauds, avec une geometric fixe, dont la chaleur provient dune reaction chimique irreversible fortement exothermique entre un com- bustible et un comburant. La flamme comprend en general une zone de combustion primaire (dard), une zone de combustion secondaire (panache) et une zone intermedia
31、ire. 2.3.2 combustible : Corps reducteur dont la combinaison avec le comburant fournit Ienergie necessaire B Iatomisation et B Iexcitation. 2.3.3 comburant : Corps oxydant dont la combinaison avec le combustible fournit Ienergie necessaire 4 Iatomisation et g Iexcitation. 2.3.4 gaz additionnels : Ga
32、z ajoutes au melange de com- bustion. Le gaz inerte diluant est non reactif, le gaz auxiliaire esf reactif. 2.3.5 flamme oxydante; flamme pauvre : Flamme obte- nue avec un exces de comburant. 2.3.6 flamme reductrice; flamme riche : Flamme obtenue avec un exces de combustible. 2.3.7 flamme skparee :
33、Flamme dans laquelle la zone de combustion secondaire est separee de la zone de combustion primaire. 2.3.8 flamme souffl la section de la flamme peut avoir une forme quel- conque. 2.3.10 flamme turbulente : Flamme dans laquelle lecoule- ment des gaz brQles seffectue par filets fluides dans toutes le
34、s directions. 2.3.11 brQleur B premelange : Brhleur dans lequel le gaz combustible, le gaz comburant et Iaerosol sont melanges avant le front de flamme. Ce brGleur produit g electrothermal atomizer : An atomizer consisting of a tube, rod, strip, fila- ment, etc., made of refractory material and heat
35、ed by a device giving an electric current at low voltage and at high intensity, providing a means of obtaining variable temperatures accor- ding to the analyte being analysed. 2.5 source datomisation Biectrothermique : Source datomisation constituee par un tube, une baguette, un ruban, un filament,
36、etc. en materiau rofractaire, chauffe par un dispo- sitif donnant un courant Blectrique a basse tension et a haute intensite permettant dobtenir des temperatures variables selon Ielement a doser consider S 4 Definitions relating to characteristics and properties of the equipment 4 Dbfinitions se rap
37、portant aux caract elle est caract two lines are separated when the ratio of the radiant flux, measured at the minimum between them, to the radiant flux of the stronger of them is less than or equal to 80 %. This ratio only applies if the two lines are of similar intensity. The resolution is express
38、ed as the ratio $ of the mean value of the two wavelengths separated (4 to the minimum dif- ference between these wavelengths (AA. 4.1.4 fidelit de Iappareil : Qualit correspondant B Iapti- tude dun appareil g donner, pour une mGme valeur de la gran- deur mesurke, des indications concordant entre el
39、les, les erreurs syst6mafiques n6tant pas prises en consid6ration. La fidelit est caract deux raies sont s6parees lorsque le rapport du flux Bnergktique, mesur6 au minimum situ6 entre elles, au flux Bnergetique de la plus forte est infbrieur ou Bgal B 80 %. Ce rapport nest valable que si les deux ra
40、ies sont dune intensit6 voisine. La r 1 - matrix effect, spectral interference, scattering effect; - chemical interference : dissociation, oxide-dissociation, ionization interference; - physical interferences : nebulization interferences, liquid- phase interferences; solute-volatilization interferen
41、ces, vapour- phase interferences; - specific and non-specific interferences for a given element. 5.2.1 perturbation : Effet qui cause une modification de labsorbance, ou de Iintensitk mesur6e relative B une concen- tration d6termitGe, par suite de la pksence dun ou plusieurs constituants accompagnan
42、t lkkment a doser dans le milieu soumis a Ianalyse.2) 5.2.2 affaiblissement; depression : Perturbation oh Iabsorbance ou Iintensit6 est diminuke. 5.2.3 exaltation : Perturbation air Iabsorbance ou Iintensitk est augmentke. 5.2.4 effet de matrice : Perturbations dues 3 la pksence dun ou plusieurs con
43、stituants accompagnant IBl6ment B doser dans I6chantillon. 5.2,5 superposition : Perturbation due B la separation spec- trale incompMe des radiations Bmises ou absorbkes par I effet de diffusion : Pertur- bation se prksentant comme une absorption non spkifique et due B la diffusion des radiations in
44、cidentes par des particules solides ou liquides presentes dans le milieu absorbant. 6.2.7 perturbation chimique 5.2.7.1 perturbation chimique de dissociation : Perturba- tion provenant dune modification de la dissociation de IM- ment B doser dans la source datomisation. 5.2.7.2 perturbation chimique
45、 doxydorkduction : Pertur- bation provenant dune modification de lequilibre doxydork duction des atomes libres de Ir%ment g doser. 1) Le terme cdnterfkrence) est souvant employ - Ieffet de matrice, la superposition, Iabsorption par diffusion; - les perturbations chimiques de dissociation, doxydor6du
46、ction et dionisation; - les perturbations physiques : perturbation de n6bulisation, perturbation en phase liquide; perturbation de fusion-volatilisation, perturbation en phase vapeur; - les perturbations spkifiques et non spkifiques dun Bkment don this substance sometimes forms part of the samples.
47、5.3.2 releaser : A buffer which suppresses or reduces a chemical interference by forming, for example, stable com- pounds with the interfering elements. An oxidation-reduction buffer decreases and stabilizes the oxidation of free atoms of the analyte element. 5.3.3 ionization buffer : A buffer which
48、 decreases and stabilizes the ionizatlon of the free atoms of the analyte by in- creasing the concentration of free electrons in the atomizer. 5.3.4 volatilizer : A substance added to the sample solution to improve the volatilization in the atomizer, either by forming a more volatile compound or by
49、increasing the total surface area of the dispersed particles of sample. 5.3.5 saturator : A buffer containing the interfering element(s) in sufficient quantity to reach the limit of enhance- ment or dispersion (he, saturation) of the interference curve, this latter being the absorbance or intensity plotted as a func- tion of the concentration of the interfering element, 6,4 Solutions 5.4.1 sample solution : A solution made up from a test por- tion of th
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