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51.
引入时间序列分析进行危岩体监测数据的处理,建立了危岩体变形的动态模型,取得了较好的拟会与预报精度。 相似文献
52.
53.
1932年甘肃昌马发生了7.5级地震。我们沿此破裂带对13个剖面进行了电测深勘探。调查的結果可用来研究这次地震破裂带的分布及其与第四纪断层分布的关系。本文主要分析了该地区的构造条件及构造应力的作用方式。 相似文献
54.
Eugene Yee R. Chan P. R. Kosteniuk G. M. Chandler C. A. Biltoft J. F. Bowers 《Boundary-Layer Meteorology》1995,73(1-2):53-90
The statistics of level crossings and local extremes in concentration fluctuations in plumes dispersing in the atmosphere have been investigated. A set of concentration fluctuation tracer experiments has been utilized to measure the statistical propertics of the upcrossing interval (inter-arrival time between consecutive concentration bursts), excursion duration (persistence or width of concentration bursts), and concentration amplitude (difference between the maximum and minimum concentrations between successive upcrossings) with respect to a range of concentration crossing levels. In particular, the effect of downwind distance and atmospheric stratification on the level-crossing statistics has been studied in detail. It is shown that the effect of increasing atmospheric stability on level-crossing statistics is similar to the effect of increasing distance from the source in the sense that level-crossing statistics of concentration fluctuations in stable stratification resemble those in neutral stratification, but at a greater downwind distance. It is also found that the distribution of the interval between consecutive upcrossings of a concentration level, as well as the duration of an excursion across a concentration level, can be approximated by a lognormal distribution, whereas the distribution of the concentration amplitude is best characterized by a gamma distribution. Some implications of these results for the modeling of level-crossing statistics of concentration fluctuations are discussed. 相似文献
55.
I. Iwasaki T. Ozawa M. Yoshida T. Katsura Chan Kuk Kim M. Aoyagi Y. Yoshiike 《Bulletin of Volcanology》1982,45(2):81-85
Many examples of mixed magmas in banded lavas have been studied. Another type of mixed magmas or inhomogeneity of magma reservoir found in the 1962 lava flows of Miyake-zima Volcano erupted from fissures is reported. 相似文献
56.
The counter-current gas-fluidized cascade (CFC) is a novel pneumatic device for separating mixed granular solids according to specific gravity. The possible utility of the CFC for beneficiation of coal in all size-ranges is presently under investigation, and in this paper some results are reported on pyrite beneficiation of synthetic pyrite-coal mixtures, and also on pyrite and ash beneficiation of as-received coal. The (geometric) mean particle size, by weight, of the coal used with added pyrite was 153 μm, and of the natural coal 233 μm. Preliminary results on the concentration of pyrite and ash in the reject streams indicate that CFC has some potential of being a simple and low-cost device for coal beneficiation. 相似文献
57.
D.J. Henry I.D.R. Mackinnon I. Chan A. Navrotsky 《Geochimica et cosmochimica acta》1983,47(2):277-282
A calorimetric study has shown that glasses along the albite-diopside join in the system albiteanorthite-diopside have positive enthalpies of mixing. Thermodynamic calculations based on these data describe a nearly symmetric, metastable, subliquidus irascibility gap along the join with a critical temperature at 910 K. The existence of the miscibility gap was tested experimentally by annealing an Ab50Di50 glass at 748 K and 823 K. Annealed glasses were examined by optical microscopy and by scanning and transmission electron microscopy. The glasses showed morphological and chemical features consistent with unmixing of two glass phases. The apparent mechanism of phase separation involves initial spinodal decomposition followed by coarsening to produce 0.1 μm–0.3 μm spherical glass phases. 相似文献
58.
Liu Qingsheng Department of Geophysics China University of Geosciences Wuhan The State Key Laboratory of Oil/Gas Reservoir Geology Exploitation of China Institute of Chengdu Technology Chengdu Wu Qifan Li Haixia Department o 《中国地质大学学报(英文版)》2001,12(2)
INTRODUCTIONThepresenceofmagneticanomaliesoveroilandgasfieldshasbeenknownforseveraldecades,butitisonlyinrecentyearsthatthephenomenonhasbeencriticallyinvestigated .Themag neticcharacteristicsofsoilandsedimentarecloselyrelatedtosomegeochemicalprocesses,s… 相似文献
59.
新疆北山地区区域重、磁场特征及其地质意义 总被引:1,自引:0,他引:1
本文在探讨新疆北山地区区域重、磁场特征的基础上,系统地叙述了北山裂谷内发育的白地洼、磁海重力高异常特征和基性、超基性岩体群重、磁场特征。指出坡北、笔架山岩带处于EW、NEE、NNW三组断裂所控制的三角形重力高的梯度带和负磁异常带上。提出通过这一特点,可以在北山地区寻找新的基性、超基性岩体群和拔矿靶区圈定。 相似文献
60.