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Both freefree processes and Comptonization were taken into account.


The photoabsorption coefficients for boundfree and freefree transitions of HH+ in the solar photosphere are calculated.


These are compared with the absorption coefficients for photoejection of an electron from a negative hydrogen ion H and freefree transitions of an electron in the field of a hydrogen atom H.


The effects of Coulomb freefree and boundfree electron interactions are classified according to their appearance in the solar interior.


The eclipses lead to variations in the radio flux (due to variations in the freefree absorption), dispersion measure, rotation measure, and linear polarization of the pulsar.

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 In this paper, we used the more rigorous general relativistic viscose hydrodynamical equation to discuss and calculate the temperature profile in the accretion disk around a Kerr black hole. We argued that in the accretion disk around a black hole, it is significant in principle for considering the release of the internal energy of the accreting materials. Taking the effect of internal energy of the accreting materials into account and using the classical theory, we have shown that the occurrence of solution... In this paper, we used the more rigorous general relativistic viscose hydrodynamical equation to discuss and calculate the temperature profile in the accretion disk around a Kerr black hole. We argued that in the accretion disk around a black hole, it is significant in principle for considering the release of the internal energy of the accreting materials. Taking the effect of internal energy of the accreting materials into account and using the classical theory, we have shown that the occurrence of solution of the abnormal temperature profile around a Schwarzschild black hole is possible. In this consistent solution, the temperature profile are not always monotonic, i.e. the temperature is not always a monotonic descending function of the raduis r, not as that of the usual case, but there exists probably a temperature profile with maximum at the certian raduis, in consequence it is existed a cooling region.In order to discuss this subject further, it is natural logically development to using the more rigorous relativistic hydrodynamical equation. Therefore, we will follow the general methods by Bardeen, J. M., Press, W. H., Teukolsky, S. A., and Novikov, I. D.. Thome, K. S. et al. to establish a possible model of accretion disk for the Kerr black hole. Our fundamental assumptions are: (1) The central plane of the disk coincides with the equatorial plane of the black hole. The disk is a perfectly aixalsymmtrie and is thin; (2) The orbital motions of the materials in the disk are controled mainly by the gravitational pull of the hole so that the orbits are very nearly geodesic, while the component of the velocity in the radial direction is very small and the motions in the direction normal to the disk may be neglected; (3) The dominate pressure is the gas pressure, but the radiative pressure is negligble; (4) The radial heat transfer is very small in comparison with the energy radiated from the surface of the disk; (5) The internal energy of the accreting materials in the disk must be calculated. Under these assumptions, our main conclusions obtained are: (1) If the radiative mechanism of the materials in the disk is the blackbody radiation, the result is coincidence with the classical theory, whatever kind of the viscose law be; (2) For freefree radiation, the temperature profile is in substance just like the classical case. Thus it is further demonstrated theoretically that there exists indeed such a possible accretion disk around the Kerr black hole which has a fast cooling ring region just laid inside the temperature maximum as its main character. In this cooling ring region, there are probably some pecularities which have not existed for the usual temperature profile.  本文采用较严格的广义相对论粘滞流体动力学方程,讨论并计算了在Kerr度规下黑洞吸积盘的温度分布问题.结果表明,对于绕Kerr黑洞的吸积盘,温度确有极大值的分布轮廓.而且,当盘内物质的辐射机制是黑体辐射时,不论粘滞机制属于何种类型,结果都一样;对于自由—自由辐射,采用a粘滞律模型,与我们在文[1]中所得的结果十分类似.这表明文[1]中所取的近似足合适的.计算还表明,在温度极大值所处半径的内面,有一迅速冷却的环状区域存在.在这一环状区域内,有可能具有某些在通常温度分布时所没有的特性.  In this paper, the modal parameters of automotive frames are identified by the real modal analysis technique based on the modal superposition principle and optimized—iteration method for the primary Values. The first order and second order matrix perturbations of distinct and multiple eigenvalues in structural dynamics are discussed. A correction procedure is presented to determine the modal parameters for the vibration of freefree structure using the experimental data of the same structure hung with elastic... In this paper, the modal parameters of automotive frames are identified by the real modal analysis technique based on the modal superposition principle and optimized—iteration method for the primary Values. The first order and second order matrix perturbations of distinct and multiple eigenvalues in structural dynamics are discussed. A correction procedure is presented to determine the modal parameters for the vibration of freefree structure using the experimental data of the same structure hung with elastic elements. Some digital examples are given to demonstrate the application of the procedure and some conclusions are obtained. The deviation of the first natural frequency between the constrained structure and the free—free structure is about 4.0～4.5% when the first natural frequency of the structure is about three times as large as the highest rigid body frequency in the hung system. Hence, it is necessary to correct the experimental results using the matrix perturbation. These conclusions are applicable not only for automotive frame but also for other large complex structures.  本文采用以模态迭加原理为基础的实模态分析技术及初参数优选法对汽车车架的模态参数进行了识别,讨论了振动特征值问题中关于非重特征值和重特征值的矩阵摄动法,提出了利用有弹性元件悬挂的结构振动测试数据来得到自由——自由结构的模态参数的摄动修正方法.文中还给出了一些数值例子来说明此方法的应用,同时得到了一些重要结论.  POGO instability is one of important dynamical problems of space vehicles. The mechanism of the POGO instability has been clarified briefly by a simple freefree system which is only consisted of two massesspring  damper element. Then POGO stability matrix algorithm, POGO stabilitysingle transfer method and POGO stability estimation method. The adaptability of these POGO stability analysis is pointed through an example. After important parameters related to POGO instability are discussed, the reliability... POGO instability is one of important dynamical problems of space vehicles. The mechanism of the POGO instability has been clarified briefly by a simple freefree system which is only consisted of two massesspring  damper element. Then POGO stability matrix algorithm, POGO stabilitysingle transfer method and POGO stability estimation method. The adaptability of these POGO stability analysis is pointed through an example. After important parameters related to POGO instability are discussed, the reliability analysis of POGO stability and its criteria are also introduced.  跷振(POGO)稳定性是航天运载器重要动力学问题之一。本文扼要介绍所提出的不稳定性跷振机理(通过自由—自由两质量块一弹簧—阻尼器系统来说明),跷振稳定性矩阵算法,单传判别法和估算法。通过算例分析指出这些方法的适用性。在讨论跷振稳定性分析中有关重要参数之后,还介绍跷振稳定性可靠性算法及其标准。   << 更多相关文摘 
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