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991.
Renhua?ZhangEmail author Zhaoliang?Li Xiaomin?Sun Zhilin?Zhu Weimin?Wang 《中国科学D辑(英文版)》2005,48(1):53-64
This paper proposes a basic equation of thermal radiation interaction between surface objects on the basis of the principle
of heat balance in the interface. The solution of this equation takes account of the contribution of sensible heat flux and
latent heat flux more completely, compared with traditional solution for surface cooling and heating processes. By the aid
of the experimental data conducted in the Xiaotangshan experimental site, Beijing, both the non-applicability of Kirchoff’s
law and the measurability of surface emissivity in a non-isothermal system have been highlighted. Two methods called ventilation
and time-delay compensations have been proposed to reduce the error induced by change of surface temperatures of non-isothermal
objects during the measurement of emissivity. Based on the solution of the basic equation, this paper has analyzed and pointed
out the misunderstanding in comprehension and application of Kirchoff’s law published in literature. 相似文献
992.
In this paper, authors obtain the spectral peaks of the earth free oscillation and check all normal modes from 0S0 to 0S48 accurately, with the Fourier analysis and the maximum entropy spectrum method dealing jointly with six groups of the observational
residual data from five international superconducting gravimeter stations. By comparing the observational results in this
paper with three former groups of observations or models, authors notice an extra discrepancy between two observational 0S2 modes excited separately by Peru earthquake and Alaska earthquake, which probably mirrors the anisotropy of the Earth’s inner
core. The analysis on the splitting 1S2 mode shows that the asymmetric factor of rotationwise spectral splitting is possible to be different from that of anti-rotationwise
spectral splitting. 相似文献
993.
Francisco Carrasco Bartolom Andreo Cristina Lin Jacques Mudry 《Comptes Rendus Geoscience》2006,338(16):1203-1212
We analysed the stable isotopes (18O and 2H) of rainwater and drip water within a cave (Nerja Cave) located in the unsaturated zone of a carbonate aquifer. Rainfall is more abundant and presents lower isotopic content in winter, while the volume of drip water is greater and its isotopic content is lower in summer. The flow analysis of 18O through the unsaturated zone confirms the seasonal lag between rainfall and the appearance of drip water in the cave and reveals that the unsaturated zone of the aquifer, in the sector of the cave, behaves like an inertial system with a strong capability to modulate the input signal. To cite this article: F. Carrasco et al., C. R. Geoscience 338 (2006). 相似文献
994.
P. Rajitha R.P. Chhabra N.E. Sabiri Jacques Comiti 《International Journal of Mineral Processing》2006
The free settling velocity of cylinders and disks falling in quiescent Newtonian and power law liquids has been measured over wide ranges of experimental conditions of the particle Reynolds number (10− 5–∼300), power law flow behaviour index (0.31–1) and the length-to-diameter ratio, ∼0.4–∼14. The corresponding range of sphericity is 0.62 to 0.86. An existing drag expression which has been tested extensively for spherical particles falling in Newtonian and in power law fluids has been slightly modified here for non-spherical particles. In particular, the use of this drag expression necessitates a knowledge of an equal volume sphere diameter (to evaluate the Reynolds number and drag coefficient) and the ratio of the surface area to the projected area of a non-spherical particle. With these modifications, the approach outlined here reproduces the present and the literature data for a wide range of non-spherical particles including cones, prisms, needles, cylinders settling in both Newtonian and power law fluids with reasonable levels of accuracy. 相似文献
995.
K. Miyazaki 《Journal of Metamorphic Geology》2001,19(2):155-164
This paper examines the spatial statistics of matrix minerals and complex patterned cordierite porphyroblasts in the low‐pressure, high‐temperature (low P/T) Tsukuba metamorphic rocks from central Japan, using a density correlation function. The cordierite‐producing reaction is sillimanite + biotite + quartz = K‐feldspar + cordierite + water. The density correlation function shows that quartz is distributed randomly. However, the density correlation functions of biotite, plagioclase and K‐feldspar show that their spatial distributions are clearly affected by the formation of cordierite porphyroblasts. These observations suggest that cordierite growth occurred through a selective growth mechanism: quartz adjacent to cordierite has a tendency to prevent the growth of cordierite, whereas other matrix minerals adjacent to cordierite have a tendency to enhance the growth of cordierite. The density correlation functions of complex patterned cordierite porphyroblasts show power‐law behaviour. A selective growth mechanism alone cannot explain the origin of the power‐law behaviour. Comparison of the morphology and fractal dimension of cordierite with two‐dimensional sections from a three‐dimensional diffusion‐limited aggregation (DLA) suggests that the formation of cordierite porphyroblasts can be modelled as a DLA process. DLA is the simple statistical model for the universal fractal pattern developed in a macroscopic diffusion field. Diffusion‐controlled growth interacting with a random field is essential to the formation of a DLA‐like pattern. The selective growth mechanism will provide a random noise for the growth of cordierite due to random distribution of quartz. Therefore, a selective growth mechanism coupled with diffusion‐controlled growth is proposed to explain the power‐law behaviour of the density correlation function of complex patterned cordierite. The results in this paper suggest that not only the growth kinetics but also the spatial distribution of matrix minerals affect the progress of the metamorphic reaction and pattern formation of metamorphic rocks. 相似文献
996.
This paper identifies imbalanced columns (or rows) as a significant source of ill‐conditioning in the preconditioned coefficient matrix using the standard Jacobi preconditioner, for finite element solution of Biot's consolidation equations. A simple and heuristic preconditioner is proposed to reduce this source of ill‐conditioning. The proposed preconditioner modifies the standard Jacobi preconditioner by scaling the excess pore pressure degree‐of‐freedoms in the standard Jacobi preconditioner with appropriate factors. The performance of such preconditioner is examined using the symmetric quasi‐minimal residual method. To alleviate storage requirements, element‐by‐element iterative strategies are implemented. Numerical experiment results show that the proposed preconditioner reduces both the number of iteration and CPU execution time significantly as compared with the standard Jacobi preconditioner. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
997.
陈伟斌 《广东海洋大学学报》2002,22(2):58-62
市场经济的发展为法治与德治的统一提供了社会条件。全面加强社会主义法制建设和道德建设对于发展社会主义市场经济 ,建设有中国特色的社会主义具有重大的意义 相似文献
998.
The Ekman boundary-layer model is extended analytically for a gradually varying eddy diffusivity K(z) ≥ 0, z ≥ 0. A solution for the Ekman layer is provided having similar structure to the constant-K case; that is, exponentially decaying sine functions for the two horizontal wind components. The analytical asymptotic solution compares well with its numerical counterpart for various K(z). The result can be useful in theoretical studies such as Ekman pumping, for efficient estimation of the Ekman layer profiles in various analyses with near-neutral stratifications, or for a rapid initialization of mesoscale models. 相似文献
999.
1000.
从实践出发,总结了如“人治”等传统势力的影响、“小不管大”、条块分割、政出多门等是导致矿政执法难的重要原因,特别是“长官”意志、地方保护评论的干扰,常常使矿政执法成为一句空话。因此,做好矿管行政执法工作,必须建立建全矿管机构并赋予其执法主体地位,不断完善法律法规,加强法制宣传,加大矿政执法力度,正视工作中遇到的各种困难,研究对策,不断寻求矿管工作的新思路,新举措。 相似文献