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用1985~1995年期间海洋角动量变化序列和大气角动量变化序列,分析它们对Chandler摆动的激发能量以及它们与天文观测激发的相干性. 结果表明,在Chandler摆动频带内,海洋角动量变化提供的激发能量大约占观测激发的64髎,其中洋底压力变化起主导作用;NCEP/NCAR(美国国家环境预测中心/国家大气研究中心)和JMA(日本气象厅)大气角动量变化提供的激发能量分别为观测激发的23髎和214髎. 海洋激发与观测激发的相干系数约为0.52,接近99髎置信度下限(0.54),海洋激发的相位滞后观测激发约19°;NCEP/NCAR和JMA的大气激发与观测激发的相干系数分别为0.32和0.37,大气激发的相位超前观测激发分别约47°和19°. 用更短期间(9年、6年)的海洋和大气角动量序列与更长期间(16、39年)的大气角动量序列作分析表明,在Chandler摆动频带内,无论是它们的激发能量,还是它们与观测激发之间的相干系数都呈现很大的变化,而且这些变化具有某种程度的随机性. 相似文献
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本文分析了在新乡和临潼两地同时接收Omega导航台的H台和C台信号的相位变化。从四条传播路径的测试结果中,分析了TE模的存在以及特点。通过一组导出的方程组,从C台信号的测试数据中,用实验回归法确定出TE1模的激励因子。结果表明,VLF信号夜间向西传播时,测出的TE1模的激励因子看来比理论给出的数值要大。 相似文献
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地球自由核章动(FCN)是地幔与液核相互作用的重要动力学现象,其激发机制涉及地表流体层、地幔和地核等圈层之间的耦合,此前研究多利用地表流体层角动量数据单独研究其对FCN的激发,对核幔耦合的影响考虑不足.本文基于角动量守恒理论分析了核幔耦合对FCN周期及振幅的影响,并结合多个大气及海洋角动量函数时间序列首次估算了核幔耦合在FCN激发过程中的贡献.结果表明核幔耦合对FCN周期产生的固定和时变影响对FCN激发的作用均不可忽视,尤其时变影响可达几十个微角秒,对于进一步解释FCN时变特征非常重要;核幔耦合对FCN振幅的直接影响是地表流体层的激发与实测FCN不相符的主要原因,黏滞、电磁和地形等耗散耦合的存在对地表流体的激发振幅有67%左右的减弱效果. 相似文献
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Vladimir A. Krasnopolsky 《Planetary and Space Science》2011,59(8):754-766
A scheme of excitation, quenching, and energy transfer processes in the oxygen nightglow on the Earth, Venus, and Mars has been developed based on the observed nightglow intensities and vertical profiles, measured reaction rate coefficients, and photochemical models of the nighttime atmospheres of the Venus and Mars. The scheme involves improved radiative lifetimes of some band systems, calculated yields of the seven electronic states of O2 in termolecular association, and rate coefficients of seven processes of electronic quenching of the Herzberg states of O2, which are evaluated by fitting to the nightglow observations. Electronic quenching of the vibrationally excited Herzberg states by O2 and N2 in the Earth's nightglow is a quarter of total collisional removal of the O2(A, A′) states and a dominant branch for the O2(c) state. The scheme supports the conclusion by Steadman and Thrush (1994) that the green line is excited by energy transfer from the O2(A3Σu+, v≥6) molecules, and the inferred rate coefficient of this transfer is 1.5×10−11 cm3 s−1. The O2 bands at 762 nm and 1.27 μm are excited directly, by quenching of the Herzberg states, and by energy transfer from the O2(5Πg) state. Quenching of the O2 band at 762 nm excites the band at 1.27 μm as well. Effective yield of the O2(a1Δg) state in termolecular association on Venus and Mars is ∼0.7. Quantitative assessments of all these processes have been made. A possible reaction of O2(c1Σu−)+CO is a very minor branch of recombination of CO2 on Venus and Mars. Night airglow on Mars is calculated for typical conditions of the nighttime atmosphere. The calculated vertical intensity of the O2 band at 1.27 μm is 13 kR, far below the recently reported detections. 相似文献
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渤海有色溶解有机物的三维荧光光谱特征 总被引:1,自引:0,他引:1
本文采用三维荧光光谱(FEEMs)技术, 结合FEEMs特定光谱区荧光区域积分(FRI)法, 测定了2010年9月中旬渤海23个站位不同层次的有色溶解有机物(CDOM)样品, 以探讨渤海CDOM组分的水平和垂直分布特征以及控制因素。FEEMs的总累计积分和各荧光团的荧光区域积分比例可作为表征海域CDOM分布特征的一个良好指标, 且优于常规的单点荧光法。结果表明, 渤海CDOM中含有类腐殖质荧光团A、B、C, 类色氨酸荧光团M, 以及类酪氨酸荧光团N。从沿海至外海, CDOM总累计积分值不断减小。其中紫外区类腐殖质A的荧光区域积分比例无显著变化; 可见区陆源类腐殖质B的荧光区域积分比例也不断减小, 表明陆源输入为沿海区域CDOM的主要来源; 而可见区海源类腐殖质C、类蛋白质荧光团M、N的荧光区域积分比例和叶绿素浓度不断升高, 显示了生物活动的贡献。从层次来看, 沿海CDOM的总累计积分为: 表层>底层>中层; 而外海CDOM的总累计积分呈相反趋势。其中, 紫外区类腐殖质A的荧光区域积分比例在整个海域最小, 垂直分布无明显变化; 可见区陆源类腐殖质B的荧光区域积分比例与沿海CDOM总累计积分相一致; 可见区海源类腐殖质C、类蛋白质M和N的荧光区域积分比例与外海CDOM总累计积分相一致, 这反映了CDOM的垂直分布是由光化学反应、生物作用和沉积物再悬浮共同控制的特性。 相似文献
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水库大容量气枪震源激发条件优化实验研究 总被引:1,自引:0,他引:1
Through manual pickup of seismic phases,the number of recording stations,the farthest observation distance of station and received energy are determined,then optimal operating condition processing software is developed to evaluate the excitation effect of operating conditions. The optimal operating conditions in the Mianhuatan Reservoir are determined using this software. They are: optimal water depth 25 m,airgun array sink depth 9m and airgun array size 7m × 7m. At the same time,accumulative stacking results for every 10 times are analyzed for 300 fixed-point excitations. It is concluded that the excitation effect shows a rapidly rising trend at 10 to 90 times stacking,a slowly rising trend at 100 to 150 times stacking,a rapidly rising trend at 160 to 240 times stacking,and a slowly rising trend at 250 to 300 times stacking. As the number of stacking increases,the propagation distance and the number of recording stations also increase gradually. 相似文献