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81.
Spectra of (10)B monoisotopic diborane, B(2)H(6), have been recorded at high resolution (2-3 x 10(-3) cm(-1)) by means of Fourier transform spectroscopy in the region 700-1300 cm(-1). A thorough analysis of the nu(18) a-type, nu(14) c-type, and nu(5) symmetry-forbidden band has been performed. Of particular interest are the results concerning the nu(5) symmetry-forbidden band, which is observed only because it borrows intensity through an a-type Coriolis interaction with the very strong nu(18) infrared band located approximately 350 cm(-1) higher in wavenumber. The nu(5) band has been observed around 833 cm(-1) and consists of a well-resolved Q branch accompanied by weaker P- and R-branch lines. Very anomalous line intensities are seen, with the low K(a) transitions being vanishingly weak, and Raman-like selection rules observed. The determination of the upper state Hamiltonian constants proved to be difficult since the corresponding energy levels of each of the bands are strongly perturbed by nearby dark states. To account for these strong localized resonances, it was necessary to introduce the relevant interacting terms in the Hamiltonian. As a result the upper state energy levels were calculated satisfactorily, and precise vibrational energies and rotational and coupling constants were determined. In particular the following band centers were derived: nu(0) (nu(5)) = 832.8496(70) cm(-1), nu(0) (nu(14)) = 977.57843(70) cm(-1), and nu(0) (nu(18)) = 1178.6346(40) cm(-1). (Type A standard uncertainties (1varsigma) are given in parentheses.) Copyright 2000 Academic Press.  相似文献   
82.
Using 0.002 cm(-1) resolution Fourier transform absorption spectra of an (17)O-enriched ozone sample, an extensive analysis of the nu(3) band together with a partial identification of the nu(1) band of the (17)O(16)O(17)O isotopomer of ozone has been performed for the first time. As for other C(2v)-type ozone isotopomers [J.-M. Flaud and R. Bacis, Spectrochim. Acta, Part A 54, 3-16 (1998)], the (001) rotational levels are involved in a Coriolis-type resonance with the levels of the (100) vibrational state. The experimental rotational levels of the (001) and (100) vibrational states have been satisfactorily reproduced using a Hamiltonian matrix which takes into account the observed rovibrational resonances. In this way precise vibrational energies and rotational and coupling constants were deduced and the following band centers nu(0)(nu(3)) = 1030.0946 cm(-1) and nu(0)(nu(1)) = 1086.7490 cm(-1) were obtained for the nu(3) and nu(1) bands, respectively. Copyright 2000 Academic Press.  相似文献   
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84.
Using both high resolution (0.0018 cm?1) and medium resolution (0.112 cm?1) Fourier transform spectra of an enriched 34S (95.3%) sample of sulfur dioxide, it has been possible to accurately measure a large number of individual line intensities for some of the strongest of the SO2 bands, i.e. ν1, ν3 and ν1+ν3. These intensities were least-squares fitted using a theoretical model which takes into account the vibration–rotation interactions linking the upper energy levels where needed, and, in this way, expansions of the various transition moment operators were determined. The Hamiltonian parameters determined in previous analyses together with these moments were then used to generate synthetic spectra for the bands studied and their corresponding hot bands providing one with an extensive picture of the absorption spectrum of 34SO2 in the spectral domains, 8.7, 7.4, and 4 μm.  相似文献   
85.
Fourier transform spectra of oxirane (ethylene oxide, c-C2H4O) have been recorded in the 730–1560 cm?1 (6.4–13.7 μm) spectral region using a Bruker IFS125HR spectrometer at a resolution of 0.0019 cm?1. A total of six vibration bands, ν15, ν12, ν5, ν3, ν10 and ν2, have been observed and analyzed. The corresponding upper state ro-vibrational levels were fit using Hamiltonian matrices accounting for various interactions. Satisfactory fits were obtained using the following polyads {151, 121, 51} and {101, 21} of interacting states. As a result, an accurate and extended set of Hamiltonian constants were obtained. The following band centers were derived: ν0 (ν15) = 808.13518(60) cm?1, ν0 (ν12) = 822.27955(37) cm?1, ν0 (ν5) = 876.72592(15), ν0 (ν3) = 1270.37032(10) cm?1, ν0 (ν10) = 1471.35580(50) cm?1 and ν0 (ν2) = 1497.83309(15) cm?1 where the uncertainties are one standard deviation.  相似文献   
86.
To measure accurately OCS concentrations in planetary atmospheres, it is important to know precisely nitrogen and oxygen pressure broadening and pressure-induced shift coefficients for the lines used in the retrievals. We present in this study the corresponding coefficients for lines of the P and R branches of the 4ν2 band of the primary isotopologue of carbonyl sulfide (16O12C32S).For this purpose, infrared absorption spectra of a natural carbonyl sulfide (OCS) gas sample were recorded at an unapodized resolution of 0.004 cm−1, at room temperature for different pressures of N2 and O2, using a Bruker IFS125HR spectrometer at the LISA Laboratory in France. The line parameters were derived using the multispectrum fitting method applied to the measured shapes of the lines, including the interference effects caused by the line overlaps.The results are compared with earlier measurements and with values calculated using a semi-classical model based upon the Robert and Bonamy formalism that reproduces rather well the experimental m (m=−J for P(J) lines and m=J+1 for R(J) lines) quantum number dependence of the N2 and O2 broadening coefficients. On the other hand most of the lines studied here have positive shift coefficients, which do not show any systematic dependence on m. However, in previous studies of the ν3, 2ν3 and ν2 bands, these coefficients were negative for all lines.  相似文献   
87.
The design and operations of inpatient care facilities are typically largely historically shaped. A better match with the changing environment is often possible, and even inevitable due to the pressure on hospital budgets. Effectively organizing inpatient care requires simultaneous consideration of several interrelated planning issues. Also, coordination with upstream departments like the operating theatre and the emergency department is much-needed. We present a generic analytical approach to predict bed census on nursing wards by hour, as a function of the Master Surgical Schedule and arrival patterns of emergency patients. Along these predictions, insight is gained on the impact of strategic (ie, case mix, care unit size, care unit partitioning), tactical (ie, allocation of operating room time, misplacement rules), and operational decisions (ie, time of admission/discharge). The method is used in the Academic Medical Center Amsterdam as a decision-support tool in a complete redesign of the inpatient care operations.  相似文献   
88.
89.
90.
A thorough ro-vibrational analysis of the hybrid (A- and B-type) ν2 bands of 35ClONO2 and 37ClONO2 has been carried out using a high-resolution (0.0009 cm?1) Fourier transform spectrum recorded at 190?K. Unlike previously studied infrared bands, weak pP- and rR-branch series were observed. From these transitions, very high Ka upper-state energy levels were obtained which permitted a satisfactory modelling of the strong Q-branch at ≈1292.5?cm?1. Accurate upper-state constants have been derived for all bands including the following band centres: ν02)?=?1292.83690(40)?cm?1 and ν02)?=?1293.20801(50)?cm?1 for the 35Cl and 37Cl isotopomers respectively.  相似文献   
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