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本文讨论了SO5 SU2 SU2 U1 U1及SO5 U1 U1的VCS表示.计算了SO5 U2 U2的约化矩阵元,并利用K矩阵技术确定了SO5权的多重度. 相似文献
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The infrared spectra of the 2ν1, 2ν2 and 2ν3 overtones of perchloryl fluoride, FClO3, have been recorded at high resolution using monoisotopic pure samples. Four symmetric top species have been investigated: F35Cl16O3, F37Cl16O3, F35Cl18O3 and F37Cl18O3. The vi = 2, i = 1, 2, 3 vibrationally excited states are totally symmetric, so these overtones correspond to parallel bands of medium/weak intensity, centered from 2010 to 2120 cm−1 (2ν1), from 1390 to 1430 cm−1 (2ν2) and from 1070 to 1100 cm−1 (2ν3). Most of the bands are unperturbed and their analysis was straightforward. The band origins, the rotational and centrifugal molecular constants in the v1 = 2, v2 = 2 and v3 = 2 states have been determined, with standard deviations of the fits from 0.00024 to 0.00067 cm−1. The 2ν1 overtones of F35Cl16O3 and F37Cl16O3 are perturbed by an A1/E Coriolis resonance between the v1 = 2 state and one E component of the v4 = 1, v6 = 2 manifold. The 2ν2 of F37Cl18O3 is perturbed by the same kind of interaction involving the v1 = v6 = 1 (E) state, at about 1396 cm−1. In these bands the resonance is localized on rotational levels with specific J and K values. As a consequence, a few transitions of the perpendicular bands involving the interacting levels could be identified in the spectra. A simultaneous fit of the transitions assigned to the dyads has been performed and the parameters of the excited states have been determined, including the high order Coriolis interaction coefficient . The anharmonic constants x11, x22, x33 of all the studied isotopologues of FClO3, x46 of F35Cl16O3, x46 + g46 of F37Cl16O3 and x16 of F37Cl18O3, have been derived. 相似文献
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用自洽LMTO-ASA方法研究了ScH2及HfH2的电子结构,毋需在面心晶格的八面体中心位置上加入一个额外的球作为muffin-tin势的修正,关于ScH2本结果与Peterman及Harmon的计算结果及光电子谱结果十分一致;除去21的位置处在Fermi能级之下,因而在ScH2中H也可能占据八面体位置。HfH2状态密度的大致轮廓定性上与光电子谱结果是符合的。H原子带有1.2—1.3个电子电荷。
关键词: 相似文献
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本文应用基于二极管激光器的双路光腔衰荡光谱技术,分别对大气中NO3和N2O5浓度进行监测. 通过使用实验室标准样校正有效吸收腔长比RL和系统的总损耗系数?,并获得了NO3有效吸收截面. 该装置在时间分辨率为1 s时,对NO3的测量灵敏度达到1.1 pptv,N2O5被在线转换成NO3,从而被另一路光腔衰荡光谱装置探测. 利用该装置,对合肥市区冬季夜间大气中的NO3,N2O5浓度进行了实时监测. 通过对比一次大气快速清洁过程中氮氧化物、臭氧、PM2.5等组分的浓度变化,讨论了大气环境下可能影响NO3及N2O5浓度的因素. 相似文献
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Pressure-induced line shift coefficients have been measured for more than 200 rovibrational lines of NH3 perturbed by O2 at room temperature (T = 295 K) in some branches of the ν2, 2ν2, and ν4 bands. These lines with J values ranging from 1 to 13 are located in the spectral range 800-1800 cm−1. Experiments were made with a high-resolution Fourier transform spectrometer. The treatment of vibration-rotation lines includes interference effects caused by the overlapping of lines. The O2 pressure-induced shift coefficients have been derived from the non-linear least-squares multi-pressure fitting technique. The results illustrate a vibrational dependence of line shifts with vibrational quantum number. Most of the measured shifts are negative in the ν4 band. They are positive for the ν2 and 2ν2 bands. The measured shift coefficients are compared with previous measurements and with those calculated from a semiclassical theory based upon the Robert-Bonamy formalism extended to the case of symmetric top molecule with inversion motion. The predictions are generally in satisfactory agreement with the experimental data. Analyses of measured and predicted results illustrate that these shifts mainly originate from the isotropic part of the intermolecular potential. 相似文献
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TiO2, RuO2, and IrO2 transition metal oxides have many applications in the field of applied electrochemistry. In this work, the mixed solid solutions of TiO2–RuO2–IrO2 coatings have been electrodeposited from aqueous–unaqueous baths. 相似文献
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主要讨论了电子束蒸发SiO2/HfO2薄膜的面形控制和损伤性能。研究了电子束蒸发工艺参数对薄膜应力以及面形的影响;分析了制备工艺对薄膜吸收、节瘤缺陷密度的影响,测量了制备薄膜的损伤阈值。研究结果表明:调整SiO2蒸发时的氧分压可以有效地将薄膜的应力控制在-250~-50 MPa。同时采用金属Hf蒸发可以显著地将节瘤缺陷密度从12.6 mm-2降低至2.7 mm-2,同时将损伤阈值从30 J/cm2提高至55 J/cm2。 相似文献
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The purpose of this paper is to investigate the interplay between the chemical shielding anisotropy and quadrupole interaction in MQMAS spectra.
in the compounds Na3Co(NO2)6 and trans-Co[(en2)(NO2)2]NO3 provides model systems for such an investigation. Furthermore, only few results have been reported on the application of the MQMAS method to a spin I=7/2. The possibilities of the MQMAS spectroscopy for determining the relative orientation of the two tensors and its advantage over previous techniques are discussed. Reported experimental spectra at different spinning speeds of Na3Co(NO2)6 are accurately reproduced by our theoretical simulations. The calculations are based on a recent approach, summarized in the present paper, which allows one to perform efficient simulations of MQMAS spectra including all interactions and their time-dependence throughout the experiment. This is necessary for calculating accurate MQMAS spectra including the spinning sideband pattern. In the case of trans-Co[(en2)(NO2)2]NO3 where the quadrupolar interaction and chemical shielding are stronger and their axes are non-coincident, the MQMAS spectrum is strongly distorted due to the unsufficient spinning speed and RF power. In this case, MAS at different spinning speeds is shown to provide valuable information. 相似文献
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利用单模连续的钛宝石激光器, 构建了一台光腔衰荡光谱仪, 其可探测的最小吸收可达1.8×10-10/cm. 该光谱仪被用来记录C2H2分子在12240~12350 cm-1的泛频光谱. 与在同一波段测量的已报到的CRDS和激光腔内吸收光谱仪结果比较,本测量同时具有更好的灵敏度和精度. 由此,获得了乙炔分子在12290.12、12311.82和12350.61 cm-1附近高泛频谱带更准确的振转参数 相似文献
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T. Wu W. Chen E. Fertein F. Cazier D. Dewaele X. Gao 《Applied physics. B, Lasers and optics》2012,106(2):501-509
We report on the development of an optical instrument based on incoherent broadband cavity-enhanced absorption spectroscopy
(IBBCEAS) for simultaneous open-path measurements of nitrous acid (HONO) and nitrogen dioxide (NO2) in ambient air using a UV light emitting diode operating at ∼366 nm. Detection limits of ∼430 pptv for HONO and ∼1 ppbv
for NO2 were achieved with an optimum acquisition time of 90 s, determined by an Allan variance analysis. Based on a 1.85 m long
high optical finesse open-path cavity, the effective optical path length of 2.8 km was realized in aerosol-free samples or
in an urban environment at modest aerosol levels. Such a kilometer long optical absorption is comparable to that achieved
in the well established differential optical absorption spectroscopy (DOAS) technology while keeping the instrument very compact.
Open-path detection configuration allows one to avoid absorption cell wall losses and sampling induced artifacts. The demonstrated
sensitivity and specificity shows high potential of this cost-effective and compact infrastructure for future field applications
with high spatial resolution. 相似文献
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T. Bohm N. Ditzian G. Peiter H.-R. Volpp S. Cheskis J. Wolfrum 《Proceedings of the Combustion Institute》2005,30(2):2131-2139
Absolute CN and CH radical concentrations were determined in situ during the combustion of a graphite substrate in premixed, laminar, low-pressure, H2/O2 flames for two different equivalence ratios, = 1.0 and = 1.5. For CN measurements, a small amount of NO (1.8%) was added. The concentration of CN was measured by cavity ring-down spectroscopy (CRDS) probing the absorption of the P1,2 (13) in the B–X (0, 0) band at 388.1 nm, and the concentration of CH was measured by linear unsaturated laser-induced fluorescence (LIF) exciting the fluorescence of the R1 (4) in the B–X (0, 0) band at 387.4 nm. Temperature measurements were done based on LIF excitation spectra of OH in the A–X (0, 0) band. It was found that the graphite substrate reduces the flame temperature in the vicinity of its surface. The CN concentrations were found to be three times higher for the rich flame than for the stoichiometric flame. CH concentrations were slightly higher for the stoichiometric flame than for the rich flame. The observed CH/CN concentration ratio is substantially lower compared to NO-doped low-pressure CH4/O2 flames. The obtained quantitative information can serve as a first calibration point for detailed numerical simulations of the burning solid graphite, which are based on the concept of surface elementary reactions. 相似文献
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EPR measurements on crystals of compressed tetragonal Rb2PbCu(NO2)6 and K2PbCu(NO2)6 subjected to uniaxial stress have been carried out at various temperatures. The results indicate that uniaxial stress can reorient the crystal axes in both compounds and that smaller stresses are required for Rb2PbCu(NO2)6 than for K2PbCu(NO2)6 at comparable temperatures. Larger stresses are required at lower temperatures. 相似文献
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多轴差分吸收光谱技术(MAX-DOAS)通过测量不同角度的太阳散射光, 获取痕量气体的柱浓度信息, 广泛应用于整层NO2柱浓度的监测. 由于缺少有效观测距离的信息, MAX-DOAS无法获取近地面NO2的体积混合比浓度. 本文分析了消光系数和有效观测距离的关系, 提出了利用能见度信息获取有效观测距离, 进而将MAX-DOAS测量的水平方向NO2斜柱浓度转换为体积混合比浓度的方法. 并在合肥开展了相应的观测实验, 成功实现了基于MAX-DOAS的NO2体积混合比浓度测量. 通过与主动式长程差分吸收光谱仪测量的NO2浓度进行对比, 结果呈现出较好的一致性, 说明了方法的可行性.研究为MAX-DOAS监测近地面NO2体积混合比浓度提供了一种简单有效的方法, 拓展了MAX-DOAS的应用领域.
关键词:
多轴差分吸收光谱技术
大气消光系数
能见度
2体积混合比浓度')" href="#">NO2体积混合比浓度 相似文献
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Laboratory measurements of the absorption coefficients of NO2 at wavelengths suitable for the operation of differential absorption lidar (DIAL) systems, at around 446 nm and 489 nm are reported. Such measurements are necessary for the valid determination of absolute levels of concentration of NO2 in the atmosphere and have been made in order to assess anomalies in existing data. A theoretical assessment of some of the optional systems currently available for the application of DIAL to the measurement of atmospheric concentrations of SO2 is described. 相似文献
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The action of the monovalent M+ cations on the luminescent properties of the mixed M
x
(1)
M
1-x
(2)
UO2(NO3)3 crystals, where M is Na, K, Rb, Cs, or NH4 , has been investigated. It has been established that the spectral positions of the bands of vibronic transitions depend linearly on the ratio between the concentrations of the M(10) and M(2) cations. It is shown that the crystals considered are composed of l[RbUO2(NO3)3]n[CsUO2(NO3)3] clusters, where l/n = x/(1 - x). The spectral regularities revealed are determined by the partial contributions of the M(1) and M(2) cations to their combined, polarizing action on the uranyl complex and are explained by the ligand nature of its highest occupied molecular orbital.Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 71, No. 6, pp. 827–830, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
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Yankuan Liu Han Wang Yongchun Zhu Xiaoqing Wang Xiaoyan Liu Haibo Li Yitai Qian 《Solid State Communications》2009,149(37-38):1514-1518
The concentration of the Mn(NO3)2 solution has significant influence on the morphologies and the phases of the MnO2 products. A large number of ε- MnO2 nanowires were prepared via a simple pyrolysis under lower reaction concentration. The nanowires have lengths up to tens of micrometers and diameters in the range of 20–100 nm. The β- MnO2 nanobundles and nanoflowers were prepared by increasing the concentration of Mn(NO3)2 solution. The superparamagnetism of ε- MnO2 nanowires and paramagnetism of β- MnO2 nanoflowers indicate their potential applications in magnetic materials. 相似文献