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1.
We study the fundamental modes of radiation hydrodynamic linear waves that arise from one-dimensional small-amplitude initial fluctuations with wave number k in a radiating and scattering grey medium by taking into account the gravitational effects. The equation of radiative acoustics is derived from three hydrodynamic equations, Poisson’s equation, and two moment equations of radiation, by assuming a spherical symmetry for the matter and radiation and by using the Eddington approximation. We solve the dispersion relation as a quintic function of angular frequency ω, the wave number k being a real parameter. Numerical results reveal that wave patterns of five solutions are distinguished into three types: the radiation-dominated, type 1, and type 2 matter-dominated cases. In the case of no gravitaional effects (Kaneko et al., 2005), the following wave modes appear: radiation wave, conservative radiation wave, entropy wave, Newtonian-cooling wave, opacity-damped and cooling-damped waves, constant-volume and constant-pressure diffusions, adiabatic sound wave, cooling-damped and drag-force-damped isothermal sound waves, isentropic radiation-acoustic wave, and gap mode. Meanwhile, the gravitaional effects being taken into account, the growing gravo-diffusion mode newly arises from the constant-pressure diffusion at the point that k agrees with Jeans’ wave number specified by the isothermal sound speed. This mode changes to the growing radiation-acoustic gravity mode near the point that k becomes Jeans’ wave number specified by the isentropic radiation-acoustic speed. In step with a transition between them, the isentropic radiation-acoustic wave splits into the damping radiation-acoustic gravity mode and constant-volume diffusion. The constant-volume diffusion emerges twice if the gravitational effects are taken into account. Since analytic solutions are derived for all wave modes, we discuss their physical significance. The critical conditions are given which distinguish between radiation-dominated and type 1 matter-dominated cases, and between type 1 and type 2 matter-dominated cases. Waves in a self-gravitating scattering grey medium are also analyzed, which provides us some hints for the effects of energy and momentum exchange between matter and radiation. 相似文献
2.
Near-surface upward irradiances within each band of the MSS (multi spectral scanner) of LANDSAT, were computed from observed spectral upward irradiances measured just beneath the sea surface. Computation of these irradiances is a useful first step in the analysis of remotely-sensed radiance because the data are not affected by the effects of the atmosphere and sea surface. The computed irradianceE in LANDSAT bands 4, 5 and 6 was normalized by forming ratios,i.e., R
45=E4/E5, R46=E4/E6, andR
56=E5/E6, and then the relationship between these ratios and chlorophylla plus phaeopigment concentration (C) observed simultaneously at 59 stations was examined by linear regression analysis. The observedC ranged over nearly three orders of magnitude, and there is a close to linear relationship between log10-R
45 and log10
C. This suggests that it may be possible to evaluateC from LANDSAT data, if an appropriate atmospheric correction is made. The relationship between suspended solids determined at 35 stations and the same ratios of upward irradiance is also presented and discussed. 相似文献
3.
提出了一种用于处理多高光谱卫星数据的UPDM分析方法。研究结果证明.该方法应用干Landsat/TM(ETM^-)、Terra/MODIS和ADEOS—II/GLI等高光谱卫星传感器时.光谱重构均方根误差小于0.029适用于研究高光谱卫星遥感数据。 相似文献
4.
Preparation of a New Geological Survey of Japan Geochemical Reference Material: Coral JCp-1 总被引:2,自引:0,他引:2
Takashi Okai Atsushi Suzuki Hodaka Kawahata Shigeru Terashima Noboru Imai 《Geostandards and Geoanalytical Research》2002,26(1):95-99
A new geochemical reference material, coral Porites sp. JCp-1 has been prepared by the Geological Survey of Japan (GSJ). Provisional values for twenty one major, minor and trace elements are presented. The homogeneity tests showed that all elements studied are considered to be homogeneously distributed. 相似文献
5.
This paper deals with an analysis method for the response and motion of soil-like rigid-plastic bodies under seismic loading conditions. A continuity condition to determine the acceleration distribution within the rigid-plastic body when the failure occurs during seismic motions is proposed. Combining this continuity condition of acceleration and the ‘Generalized Limit Equilibrium Method (GLEM)’, the responses of the earth structure during seismic motions as well as the permanent displacements can be obtained, where GLEM is one of the limit equilibrium methods proposed by the authors for static problems and providing the approximate solution for Kötter's equation. The theoretical formulation of the method, the illustrative examples, and some comparisons between the analytical and experimental results are demonstrated. 相似文献
6.
7.
Shigeru Terashima 《Geostandards and Geoanalytical Research》1984,8(1):13-16
The cadmium and lead contents of seventy-seven geological reference samples have been determined by atomic absorption spectrometry using an air-acetylene flame or a carbon tube atomizer, after extraction of cadmium and lead as iodides with methylisobutylketone (MIBK). The agreement between the present results and published data is generally good. 相似文献
8.
Akimasa Masuda Noboru Nakamura Tsuyoshi Tanaka 《Contributions to Mineralogy and Petrology》1971,32(4):295-306
Two foliated metagabbros from the Mid-Atlantic Ridge near 30° N were analyzed for rare earth elements. The chondrite-normalized rare earth pattern for one of them is quite similar to those for abyssal tholeiites. The pattern for another sample, however, is somewhat different from the above one. A new set of bulk partition coefficients for rare earth elements has been estimated correspondingly. This set throws a new light on the interpretation that many alkali olivine basalts were produced by a zone melting or partial melting of primary-liquid-type material. Also the same partition coefficients lead us to an inference that the high-temperature peridotite intrusion in the Lizard area, Cornwall, England, is a secondary-solid-type material which was once in equilibrium with a primary-solid-type material, whereas the pyroxenite, Canyon Mountain, Oregon, is a primary-solid-type material.Both of the metagabbros studied show positive europium anomaly. 相似文献
9.
Summary The spectra of Matsushiro micro-earthquakes were studied using a spectrum analyser and discussed in relation to their magnitude and the epicentral distance. It was found that the spectra of seismic waves by Matsushiro micro-earthquakes did not depend upon the epicentral distance since the sonagrams showed a peak around 5 cps at Matsushiro as well as Suzaka. The spectrum also failed to show any distinct peak for micro-earthquakes of magnitude lower than 1.0 due to the decrease of signal to noise ratio. 相似文献
10.