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1.
Two bis(bipyridine) polymeric metal nitrate complexes
with 4,4’-bipyridine of simple formula like [M(bipy)2](NO3)2⋅xH2O (where M=Co, Ni and Cu; x=4, 2 and 0, respectively) have been prepared and
characterized. Their thermal decomposition has been undertaken using simultaneous
TG-DTG-DTA and DSC in nitrogen atmosphere and non-isothermal TG in air atmosphere.
Isothermal TG has been performed at decomposition temperature range of the
complexes to evaluate the kinetics of decomposition by applying model-fitting
as well as isoconversional method. Possible mechanistic pathways have also
been proposed for the thermolysis. Ignition delay measurements have been carried
out to investigate the response of these complexes under the condition of
rapid heating. 相似文献
2.
3.
Aaron Goldman Frank J. Murcray Frank H. Murcray David G. Murcray Curtis P. Rinsland 《Mikrochimica acta》1988,95(1-6):409-415
Simultaneous total column amounts of a number of minor and trace atmospheric gases above the South Pole in December 1980 and December 1986 have been deduced from analysis of high resolution solar absorption spectra recorded (by F. J. M. and F. H. M.) from Amundsen-Scott South Pole Station. These spectra also contain some limited information on the vertical profiles of the observed atmospheric gases.The data sets were recorded with a Bomem Michelson-type interferometer and analyzed with a spectral least-squares fitting procedure, utilizing the best available spectroscopic line parameters and absorption cross sections. Because the same instrument, line parameters, and analysis method have been used in analyzing the December 1980 and December 1986 data sets, the precision in comparing the column amounts from these two dates is rather high, about 10–20% for the stronger absorbing gases. For this reason, it has been possible to quantify or determine upper limits for differences between the December 1980 and December 1986 total column amounts, of a number of atmospheric gases including O3, N2O, HNO3, CO2, CH4, and CF2C1
2 (CFC 12). In addition, vertical column amounts for a number of atmospheric gases covered only in the December 1986 observations have been derived, including HC1, NO, NO2, and C2H6. Some of these results will be discussed here. The HC1 measurements are especially interesting since the observed amounts are higher than expected from observations made at lower latitudes in the northern and southern hemispheres. 相似文献
4.
Curtis P. Rinsland Linda Chiou Chris Boone Peter Bernath Emmanuel Mahieu 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(18):2127-2134
The first measurement of the HCFC-142b (CH3CClF2) trend near the tropopause has been derived from volume mixing ratio (VMR) measurements at northern and southern hemisphere mid-latitudes for the 2004–2008 time period from spaceborne solar occultation observations recorded at 0.02 cm−1 resolution with the ACE (atmospheric chemistry experiment) Fourier transform spectrometer. The HCFC-142b molecule is currently the third most abundant HCFC (hydrochlorofluorocarbon) in the atmosphere and ACE measurements over this time span show a continuous rise in its volume mixing ratio. Monthly average measurements at northern and southern hemisphere mid-latitudes have similar increase rates that are consistent with surface trend measurements for a similar time span. A mean northern hemisphere profile for the time span shows a near constant VMR at 8–20 km altitude range, consistent on average for the same time span with in situ results. The nearly constant vertical VMR profile also agrees with model predictions of a long lifetime in the lower atmosphere. 相似文献
5.
Curtis P. Rinsland Steven W. Sharpe 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,96(2):271-280
Pressure broadened (1 atm. N2) absorption cross sections and integrated band intensities have been derived from laboratory spectra of CH3CN, recorded at 276, 298, and 323 K, covering 600-. The spectra were recorded at a resolution of using a commercial Fourier transform spectrometer and a custom flowing sample delivery system. We report integrated absorption cross sections for intervals corresponding to the most prominent bands, compare the results with previously reported values, and discuss error sources, which are estimated as ∼7% with systematic error the largest error source. 相似文献
6.
Curtis P. Rinsland Linda S. Chiou Aaron Goldman Stephen W. Wood 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,90(3-4):367-375
The average tropospheric volume mixing ratio of CHF2Cl (HCFC-22) has been retrieved from a time series of high spectral resolution ground-based infrared solar absorption spectra recorded with the McMath Fourier transform spectrometer located at the U.S. National Solar Observatory facility on Kitt Peak in southern Arizona (31.9°N, 111.6°W, 2.09 km altitude) for the time period October 1987–November 2002. The retrievals are based on fits to the well-isolated, unresolved 2ν6 Q branch at 829.05 cm−1 and the SFIT2 retrieval algorithm. The measured daily averages show a near linear rise per year in the mean tropospheric volume mixing ratio as a function of time with a best fit yielding an average increase rate of (5.66±0.15) parts per trillion (10−12) by volume per year, corresponding to (6.47±0.17)%yr−1, 1 sigma, at the beginning of the time series. The tropospheric mixing ratios retrieved from the solar spectra have been compared with monthly average surface flask sampling measurements from the Climate Monitoring and Diagnostic Laboratory (CMDL) station at Niwot Ridge, Colorado (40.0°N, 105.5°W, 3013 m altitude), archived measurement from the same location, and early CMDL northern hemisphere Pacific cruise measurements. The average ratio of the retrieved tropospheric mixing ratio relative to the CMDL surface mixing ratio is 1.053 for the overlapping 1987 to 2002 time period. The retrieved mean tropospheric mixing ratio is consistent with the surface measurements within the errors estimated for the remote sensing observations. 相似文献
7.
J.P. Bouanich A. Predoi-Cross R.L. Sams C.P. Rinsland V. Malathy Devi 《Journal of Molecular Spectroscopy》2005,231(1):85-95
A semiclassical theory based upon the Robert-Bonamy formalism has been developed to explain the experimental measurements of self-broadening, self-induced pressure shift coefficients in the ν1,ν2, 2ν2 bands of H12C14N and the 2ν1 band of H13C14N, as well as the temperature dependences of these parameters with special emphasis on the ν2 band. Our calculations include only electrostatic interactions and neglect the vibrational dependence of the isotropic part of the intermolecular potential, which probably has a weak contribution to the HCN self-shifts for the bands investigated in this study. The agreement between theory and measurements is good in the cases of self-broadening coefficients and their variation with temperature, as well as the self-shift coefficients determined at room temperature. However, the observed temperature dependence of self-shift coefficients in the ν2 band is different from that derived theoretically. 相似文献
8.
在前文工作的基础上,结合MNDO/EHMO分子轨道方法和自然杂化轨道方法,具体计算了CC键和CP键的核自旋偶合常数.计算结果表明,1JCC和1JCP主要由成键原子的轨道杂化作用和键极性这两种结构因素所决定.为从简单价键理论角度解释和计算1JCC和1JCP值提供了简便直观的方法. 相似文献
9.
Lines of the 3ν23 “forbidden” band of 12C16O2 have been identified in the 2000-cm?1 region of a long-path, 0.01-cm?1 resolution laboratory absorption spectrum. This band has detectable intensity due to Δl = 2 Fermi interactions between the upper level and the nearby ν1 + ν2 and 3ν21 levels. Intensities of 18 lines of this band have been measured using a nonlinear least-squares spectral fitting technique. The intensities are enhanced at high J and an expression for the intensity distribution as derived by Toth [Appl. Opt.23, 1825–1834 (1984)] is used for the analysis. In terms of the total sample pressure, the vibrational band intensity is 0.194 ± 0.008 × 10?30 cm?1/molecule-cm?2 at 296 K. The coefficient in the F factor is analogous to the Coriolis coefficient ξ and has been determined to be ?0.0413 ± 0.0015. As expected by theory, its value is very close to that of ξ for the related ν1 + ν2 band. 相似文献
10.
V. Malathy Devi C.P. Rinsland R.L. Sams 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(9):1234-1251
Line positions, intensities, Lorentz self- and N2-broadened half-width coefficients have been measured for PQ3, PQ2, PQ1, RQ0, RQ1, RQ2, and RQ3 sub-band transitions in the ν9 fundamental band of 12C2H6. A multispectrum nonlinear least-squares fitting technique was used to fit up to 17 high-resolution (∼0.00156 cm−1), room temperature absorption spectra of pure (99.99% chemical purity) natural sample of ethane and lean mixtures of the high-purity ethane diluted with N2. A Bruker IFS 120HR Fourier transform spectrometer located at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington was used to record the data. A standard Voigt line shape was assumed to fit all the data since no line mixing or other non Voigt line shapes were required to fit any of the spectra used in the analysis. Short spectral intervals (∼2-2.5 cm−1) of all 17 spectra covering a specific PQ or RQ sub-band were fit simultaneously. For the first time in an ethane band, pressure-broadened half-width coefficients were determined for the torsional-split components. However, for better reliability of the retrieved coefficients for the weaker components (transitions with large intensity ratios of 4:1 or 3:1 for most K levels between the strong and weak components), constraints were used such that the half-width coefficients of both torsional-split components for a given J were identical for a specific broadening gas. No pressure-induced shift coefficients were necessary to fit the spectra to their noise level. The present study revealed for the first time the dependence of self- and N2-broadened half-width coefficients upon the J, K quantum numbers of the transitions in ethane. A number of transitions belonging to the ν9+ν4−ν4 and the ν9+2ν4−2ν4 hot bands were also observed in the fitted regions and measurements were made when possible. 相似文献