Nitrogen vibrationally excited, from

Our study of sedimentary apatite from Israel proved that laser-induced time-resolved luminescence is a perspective tool for evaluation of sedimentary phosphate ores with high dolomite content (Gaft et al. 1993b). The idea was based on the fact that natural apatite contains several characteristic luminescence centers, which enables us to differentiate it from dolomite. The most widespread characteristic luminescence center in sedimentary apatite is uranyl (U02) with a typical vibrational green band luminescence under nitrogen laser excitation (Fig. 8.13a,b). Nevertheless, it appears that such luminescence is absent in phosphate rock samples from Florida, evidently because of extremely low uranium concentration (Fig. 8.13c,d). hi order to find potential liuninescence centers, ICP-MS analyses of Florida phosphates was accompHshed. From discovered REE, theoretically Dy + is the best candidate... 

Earlier work by Kaufman and Kelso250 also indicated the presence of vibrationally excited N2 from reaction (49). They observed a temperature rise in the flow stream when NaO was added downstream of the position at which NO was added to the active nitrogen. This rise was greater than that caused by the vibrationally excited N2 produced in the discharge itself. 

There have been other recent papers on the reactions discussed in Section III.B.l and III.B.2. Provencher and McKenney [414,415] have further investigated the complex excitation of CN which occurs when small quantities of carbonaceous compound are added to active nitrogen. One of their main proposals is that CN(B2Ef) is excited by transfer of energy from vibrationally excited N2 rather than from a metastable, electronically excited molecule, as implied in reaction (79). However, it seems difficult to reconcile the large rate constant which they estimate for this process with the comparative inefficiency of N2 in quenching CN(fi2Et) [416,417], Recent experiments [418, 419] do appear to have confirmed that reaction (87) does excite CO to emit chemiluminescence in the vacuum ultraviolet. The overall rate constant for the... 

Some controversy exists over the reactive species produced when nitrogen is passed through an R.f. or microwave discharge. Verbeke and Winkler investigated the reactions of active nitrogen with nitric oxide and ethylene and found that the amount of nitric oxide removed was greater than the maximum amount of HCN produced from ethylene. To account for this difference they postulated that vibrationally excited molecules were decomposing nitric oxide, viz. 

Vibrationally excited species also may give up their energy to a suitable catalytic probe. Morgan et al report calorimetric studies of vibrationally excited molecular nitrogen, and compare the results obtained with those from mass spectrometric investigations. 

Electronically excited atoms and molecules transfer energy not only into translational, but also into vibrational and rotational degrees of freedom, which is less adiabatic and faster. Fast relaxation takes place by formation of intermediate ionic complexes. For example, electronic energy transfer from excited metal atoms Me to vibrational excitation of nitrogen takes place for almost every collision ... 

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