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751.
A. S. Kirillov 《Annales Geophysicae》1998,16(7):838-846
The first-order perturbation approximation is applied to calculate the rate coefficients of vibrational energy transfer in collisions involving vibrationally excited molecules in the absence of non-adiabatic transitions. The factors of molecular attraction, oscillator frequency change, anharmonicity, 3-dimensionality and quasiclassical motion have been taken into account in the approximation. The analytical expressions presented have been normalized on experimental data of VT-relaxation times in N2 and O2 to obtain the steric factors and the extent of repulsive exchange potentials in collisions N2–N2 and O2–O2. The approach was applied to calculate the rate coefficients of vibrational-vibrational energy transfer in the collisions N2–N2, O2–O2 and N2–O2. It is shown that there is good agreement between our calculations and experimental data for all cases of energy transfer considered. 相似文献
752.
A statistical investigation of the location of onset of intermediate and gyrating ion populations in the Earths foreshock is presented based on Fixed Voltage Analyzer data from ISEE 1. This study reveals the existence of a spatial boundary for intermediate and gyrating ion populations that coincides with the reported ULF wave boundary. This boundary position in the Earths foreshock depends strongly upon the magnetic cone angle BX and appears well defined for relatively large cone angles, though not for small cone angles. As reported in a previous study of the ULF wave boundary, the position of the intermediate-gyrating ion boundary is not compatible with a fixed growth rate of the waves resulting from the interaction between a uniform beam and the ambient plasma. The present work examines the momentum associated with protons which travel along this boundary, and we show that the variation of the boundary position (or equivalently, the associated particle momentum) with the cone angle is related to classical acceleration mechanisms at the bow shock surface. The same functional behavior as a function of the cone angle is obtained for the momentum predicted by an acceleration model and for the particle momentum associated with the boundary. However, the model predicts systematically larger values of the momentum than the observation related values by a constant amount; we suggest that this difference may be due to some momentum exchange between the incident solar-wind population and the backstreaming particles through a wave-particle interaction resulting from a beam plasma instability. 相似文献
753.
The vibrational distribution of nitric oxide in the polar ionosphere computed according to the one-dimensional non-steady model of chemical and vibrational kinetics of the upper atmosphere has been compared with experimental data from rocket measurement. Some input parameters of the model have been varied to obtain the least-averaged deviation of the calculated population from experimental one. It is shown that the least deviation of our calculations from experimental measurements depends sufficiently on both the surprisal parameter of the production reaction of metastable atomic nitrogen with molecular oxygen and the profile of atomic oxygen concentration. The best agreement with the MSIS-83 profile was obtained for the value of surprisal parameter corresponding to recent laboratory estimations. The measured depression of level v = 2 is obtained in the calculation that uses sufficiently increased concentrations of atomic oxygen. It is pointed out that similar measurements of infrared radiation intensities could be used to estimate the atomic oxygen concentrations during auroral disturbances of the upper atmosphere. 相似文献
754.
Huhou Li 《中国科学D辑(英文版)》1998,41(4):437-441
The implantation of artificial quartz with nickel ion has succeeded in using a heavy ion accelerator. The quartz with nickel
ion is called ”nickel quartz“. The sensitivity of their thermoluminescence (TL) response to the beta radiation was decreased
with the increasing of irradiating and heating times. Two TL characteristics have appeared: the sensitivity of TL response
at lower temperature (ll0°C) peaks of the nickel quartz to beta radiation is higher than that of the pure quartz, this results
from the Ni+1 ion entering the quartz lattice; and a new peak appearing at 445°C may be related with both Ni+1 and Ni+3. 相似文献
755.
本文根据碘酸钡与矿物气液包裹体中SO2-4交换反应析出的碘酸根与碘化镉反应析出碘,采用碘-四氯化碳萃取光度法间接测定SO2-4,取得了较为满意的结果。 相似文献
756.
红土中含铁离子物质的化学行为与力学效应 总被引:1,自引:0,他引:1
首先从地球化学理论上分析了铁离子的化学行为力学效应及其方向性,然后通过试验,研究了不同环境水溶液化学作用后的红层黏性土和冲积黏性土中铁离子的化学行为对土体的力学效应及其特性。试验结果表明:(1)含铁离子物质与水作用后的化学行为确实存在正反两方面的双向性力学效应;(2)含铁离子物质的双向性力学效应受环境水溶液的pH值和化学成分的控制;(3)酸性水溶液使含铁离子物质的胶结作用增强,使红土强度提高,形成正方向的力学效应;而碱性水溶液使含铁离子物质的胶结作用降低,形成负方向的力学效应。 相似文献
757.
758.
759.
PHREEQC在地下水溶质反应-运移模拟中的应用 总被引:7,自引:2,他引:7
由于地下水污染的加剧,对地下水中污染物运移规律的研究日益受到重视。地下水中的溶质在运移过程中伴随着溶质组分间的化学反应,因此需要建立地下水溶质运移与化学反应的耦合模型。PHREEQC是近年来发展起来的描述局部平衡反应、动态生物化学反应的水文地球化学模拟软件。本文利用该模拟软件对一维地下水流动过程中溶质离子交换反应和动态氧化还原反应进行了模拟。结果表明,PHREEQC能够成功地进行溶质运移情况下复杂水化学反应模拟,但对于复杂地下水流和溶质运动的情况,有必要耦合其它的地下水流动和溶质运移软件来共同完成。 相似文献
760.
本文研究了单柱离子色谱法测定饮用水中微量阴离子的方法 ,样品经微孔滤膜过滤即可直接进样分析。淋洗液最佳浓度为 2 5mmol/L邻苯二甲酸氢钾溶液 ;电导检测器检测灵敏度为 3 2 μS/cm2 。该方法简便快捷、灵敏 ,选择性好 相似文献