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建筑物下采煤技术的研究现状与发展趋势 总被引:10,自引:0,他引:10
我国建筑物下采煤的研究从20世纪60年代开始,先后在本溪、鹤壁、抚顺、枣庄、峰峰、蛟河等矿区进行试验,取得了成功的经验和宝贵的监测资料。在综合分析大量文献的基础上,从协调开采法、充填开采方法、条带开采、覆岩离层注浆等多种开采技术对建筑物下开采方法进行了研究和论述;展望了我国建筑物下开采的发展趋势,认为覆岩离层注浆、矸石充填、条带开采、原地重建抗变形房将是我国建筑物下采煤技术的发展方向。 相似文献
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Radon-222 and carbon dioxide concentrations have been measured during several years at several points in the atmosphere of an underground limestone quarry located at a depth of 18 m in Vincennes, near Paris, France. Both concentrations showed a seasonal cycle. Radon concentration varied from 1200 to 2000 Bq m−3 in summer to about 800-1400 Bq m−3 in winter, indicating winter ventilation rates varying from 0.6 to 2.5 × 10−6 s−1. Carbon dioxide concentration varied from 0.9 to 1.0% in summer, to about 0.1-0.3% in winter. Radon concentration can be corrected for natural ventilation using temperature measurements. The obtained model also accounts for the measured seasonal variation of carbon dioxide. After correction, radon concentrations still exhibit significant temporal variation, mostly associated with the variation of atmospheric pressure, with coupling coefficients varying from −7 to −26 Bq m−3 hPa−1. This variation can be accounted for using a barometric pumping model, coupled with natural ventilation in winter, and including internal mixing as well. After correction, radon concentrations exhibit residual temporal variation, poorly correlated between different points, with standard deviations varying from 3 to 6%. This study shows that temporal variation of radon concentrations in underground cavities can be understood to a satisfactory level of detail using non-linear and time-dependent modelling. It is important to understand the temporal variation of radon concentrations and the limitations in their modelling to monitor the properties of natural or artificial underground settings, and to be able to assess the existence of new processes, for example associated with the preparatory phases of volcanic eruptions or earthquakes. 相似文献
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S. V. Khizhnyak I. V. Tausheva A. A. Berezikova E. V. Nesterenko D. Yu. Rogozin 《Russian Journal of Ecology》2003,34(4):231-235
The natural microflora of Middle Siberian karst cavities, which comprises psychrotolerant bacteria and fungi capable of growing at 3–15 and 3...+28°C, respectively, has been studied. Bacteria are ubiquitous in caves, their count varying from 103 to 107 cells/g ground. The bacteria have been identified as Pseudomonas, Arthrobacter, Bacillus, and coryneform bacteria. Fungi have been found in places exposed to increased anthropogenic impact, their count being as large as 106 to 107 cells/g ground. Mucor, Penicillium, and Chrysosporium were dominant fungal genera. 相似文献
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