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131.
C. Camy-Peyret J. -M. Flaud A. Mahmoudi G. Guelachvili J. W. C. Johns 《International Journal of Infrared and Millimeter Waves》1985,6(3):199-233
Using high resolution Fourier transform spectra, thev
2 band of D2O has been analysed leading to an extensive and precise set of rotational energy levels of the (0 1 0) vibrational state. These levels are reproduced very satisfactorily with a Watson type Hamiltonian and precise rotational constants as well as the band centerv
2 = 1178.3789 ± 0.0005 cm-1 are determined. A total of 61 line intensities were measured, much attention being paid to a possible contamination of the D2O sample by HDO. A least squares fit of the intensity data has provided us with an expansion of the transition moment operator of thev
2 band from which the first derivative
= 0.1690 ± 0.0030 D has been deduced. Finally the complete synthetic spectrum of this band has been computed. All these results have been used to derive improved frequencies for the known pumped and far-infrared laser lines of D2O and to predict new possible coincidences with the available CO2 laser lines. 相似文献
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133.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2392-2395
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137.
LL Handley R Azcón Ruiz Lozano JM CM Scrimgeour 《Rapid communications in mass spectrometry : RCM》1999,13(13):1320-1324
It has long been evident that plant (15)N chiefly reflects the processes which fractionate (15)N/(14)N rather than the (15)N of plant N source(s). It has emerged recently that one of the most important fractionating processes contributing to the whole plant (15)N is the presence/absence, type or species of mycorrhiza, especially when interacting with nutrient deficiency. Ecto- and ericoid mycorrhizas are frequently associated with (15)N-depleted foliar (15)N, commonly as low as -12 per thousand. As shown by the present study, plants having no mycorrhiza, or those infected with various species of arbuscular mycorrhiza (AM)-forming fungi, interact with varying concentrations of soil nitrogen [N] and moisture to enrich plant (15)N by as much as 3.5 per thousand. Hence the lack of a mycorrhiza, or variation in the species of AM-forming fungal associations, can account for about 25% of the usually reported variations of foliar (15)N found in field situations and do so by (15)N enrichment rather than depletion. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
138.
L.S. Rothman I.E. Gordon A. Barbe D.Chris Benner P.F. Bernath M. Birk V. Boudon L.R. Brown A. Campargue J.-P. Champion K. Chance L.H. Coudert V. Dana V.M. Devi S. Fally J.-M. Flaud R.R. Gamache A. Goldman D. Jacquemart I. Kleiner J. Vander Auwera 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(9-10):533-572
This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues. 相似文献
139.
A PerrinJ.-M Flaud B BakriJ Demaison O BaskakovS.V Sirota M HermanJ.Vander Auwera 《Journal of Molecular Spectroscopy》2002,216(2):203-213
The high-resolution (0.002 cm−1) spectrum of the ν7 (OCO scissor mode) and ν9 (COH torsion mode) fundamental bands of trans-formic acid (HCOOH) at 15.8 μm was recorded by Fourier transform infrared spectroscopy. In addition, millimeter-wave transitions within the 71 and 91 vibrational states were measured in the spectral range 340-600 GHz. Using these new experimental data, an extensive analysis of the ν7 and ν9 bands was performed. The model we have used accounts for the strong A- and B-type Coriolis interactions which couple the 71 and 91 vibrational states and which were already pointed out in the literature [J. C. Deroche, J. Kauppinen and E. Kyrö, J. Mol. Spectrosc.78, 379-394 (1979); E. Willemot, J. Mol. Spectrosc.120, 246-275 (1986)]. The observed levels are fit to within the experimental accuracy leading to the determination of a precise set of band centers of ν7 and ν9 at 686.1656 cm−1 and 640.7251 cm−1, respectively, and rotational and Coriolis constants. 相似文献
140.
J.-M Flaud J Orphal P.-M Flaud C Piccolo 《Journal of Quantitative Spectroscopy & Radiative Transfer》2003,77(4):355-364
Nitric acid which is an important NOx atmospheric reservoir molecule exhibits a strong absorption in the spectral region. Since this region, which corresponds to an atmospheric window, is one of the most commonly used for the retrieval of HNO3 in the atmosphere it is essential to have the best possible corresponding spectral parameters. Updates of these spectral line parameters were recently performed in the last versions of the atmospheric databases. They concern the line positions and intensities not only of the two interfering cold bands ν5 and 2ν9 but also of the ν5+ν9−ν9 hot band. This hot band exhibits indeed a sharp and strong Q branch at which is clearly observable in atmospheric spectra and is used for the retrievals. However, in spite of these recent updates, it proved that the spectral parameters of the hot band are not accurate enough to reproduce accurately the observed atmospheric HNO3 absorption in ATMOS spectra. The present paper is dedicated to a more accurate analysis of this hot band using new laboratory high-resolution (0.002-) Fourier transform spectra. As a consequence, new and more precise line positions and line intensities (about 35% weaker than in HITRAN2K) were derived leading to a significant improvement in the simulation of atmospheric spectra. 相似文献