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101.
A rigorous and systematic intercomparison of codes used for the retrieval of trace gas profiles from high-resolution ground-based solar absorption FTIR measurements is presented for the first time. Spectra were analyzed with the two widely used independent, retrieval codes: SFIT2 and PROFFIT9. Vertical profiles of O3, HNO3, HDO, and N2O were derived from the same set of typical observed spectra. Analysis of O3 was improved by using updated line parameters. It is shown that profiles and total column amounts are in excellent agreement, when similar constraints are applied, and that the resolution kernel matrices are also consistent. Owing to the limited altitude resolution of ground-based observations, the impact of the constraints on the solution is not negligible. It is shown that the results are also compatible for independently chosen constraints. Perspectives for refined constraints are discussed. It can be concluded that the error budget introduced by the radiative transfer code and the retrieval algorithm on total columns deduced from high-resolution ground-based solar FTIR spectra is below 1%. 相似文献
102.
1D-nanostructural zinc oxide (ZnO) with different shapes have been synthesized on p-type Si(1 0 0) and glass substrates via vapor phase growth by heating pure zinc powder at temperatures between 480 and 570 °C. The different ZnO nanostructures depend on the substrates and the growth temperatures. Scanning electron microscopy and X-ray diffraction revealed that a well-aligned nanowires array, which are vertical to the substrate of Si(1 0 0) with 18 sides on their heads, but six sides on their stems, has been formed at 480 °C. Raman study on the ZnO nanostructures shows that the coupling strength between electron and phonon determined by the ratio of the second- to the first-order Raman scattering cross-sections declines with decreasing diameter of the nanowires. However, a little changes of the coupling strength in terms of the width of the nanobelts have been observed. 相似文献
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104.
单壁碳纳米管的SERS研究 总被引:2,自引:2,他引:0
本文通过改进实验方法,将单壁碳纳米管的乙醇溶液与金胶混合并制作成固体薄膜,使单壁碳纳米管夹裹在金纳米粒子之间,保证了吸附的紧密性,获得了高质量的单壁碳纳米管SERS光谱。不但观测到文献中报道的径向呼吸振动模(RBM)和C-C正切拉伸模(GM)的增强,还在1100-1500cm-1区域观测到一组新峰,其峰形完整并有相当的强度。这些峰在现有的文献中几乎没有报导。文章对这组新峰的出现进行了初步的分析。 相似文献
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108.
Using a high resolution Raman spectrometer, we have measured Ar-broadening coefficients in the ν2Q branch of C2H2 for 22 lines at 295 K, 20 lines at 174 K, and 16 lines at 134 K. These lines with J values ranging from 1 to 23 are located in the spectral range 1970.9-1974.3 cm−1. The collisional widths are obtained by fitting each spectral line with a Rautian profile. The resulting broadening coefficients are compared with theoretical values arising from close coupling and coupled states calculations. A satisfactory agreement is obtained at room as well as at low temperatures, especially for odd J lines. By comparing broadening coefficients at 295, 174, and 134 K from a simple power law, the temperature dependence of these broadenings has been determined both experimentally, and theoretically. 相似文献
109.
The rotation-tunneling spectrum of the second most stable gGg′ conformer of ethylene glycol (1,2-ethanediol) in its ground vibrational state has been studied in selected regions between 77 and 579 GHz. Compared to the study of the more stable aGg′ conformer, a much larger frequency range was studied, resulting in a much extended frequency list covering similar quantum numbers, J?55 and Ka?19. While the input data were reproduced within experimental uncertainties up to moderately high values of J and Ka larger residuals remain at higher quantum numbers. The severe mixing of the states caused by the Coriolis interaction between the two tunneling substates is suggested to provide a considerable part of the explanation. In addition, a Coriolis interaction of the gGg′ ground vibrational state with an excited state of the aGg′ conformer may also contribute. Relative intensities of closely spaced lines have been investigated to determine the signs of the Coriolis constants between the two tunneling substates relative to the dipole moment components and to estimate the magnitudes of the dipole moment components and the energy difference between the gGg′ and the aGg′ conformers. Results of ab initio calculations on the total dipole moment and the vibrational spectrum were needed for these estimates. The current analysis is limited to transitions with quantum numbers J?40 and Ka?6 plus those having J?22 and Ka?17 which could be reproduced within experimental uncertainties. The results are aimed at aiding radioastronomers to search for gGg′ ethylene glycol in comets and in interstellar space. 相似文献
110.
利用拉曼型的Jaynes-Cummings模型传送两比特的未知原子态 总被引:6,自引:3,他引:3
实现量子态的隐形传送、尤其是多比特量子态的隐形传送在量子信息领域中有非常重要的作用,提出了一种隐形传送两比特未知原子态的方案,在此方案中,用两个两粒子纠缠态代替一个三粒子纠缠态作为量子信道,而且此方案可推广到隐形传送N比特的未知原子态。 相似文献