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31.
隧道地质超前预报在隧道的开挖中的作用十分重要。选择有效的预报措施,对隧道开挖中的人员、设备的安全和隧道洞室的支护具有重要的意义。TSP2203是运用地震原理对隧道进行探测的仪器。该系统从数据采集、处理实现高度智能化。本次使用此仪器对大支坪隧道横洞掌子面HDKO 064里程处进行预报,结合实际开挖,证明了预报的可行性和准确性。 相似文献
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塔里木盆地区域沙尘气溶胶特征分析 总被引:1,自引:7,他引:1
沙尘天气是塔里木盆地地区常见的天气现象,对大气沙尘气溶胶的分析表明,沙尘暴期间,沙尘气溶胶浓度远大于非尘暴期间。由于两地地理环境的差异,沙尘暴期间,策勒站细颗粒质量百分比呈下降趋势;阿克苏站细颗粒质量百分比呈上升趋势。说明尘暴期间由于当地沙尘源丰富,细粒物质较多,当风速达到起沙风速时,细粒物质迅速被携带到高空,成为沙尘气溶胶的主要来源。阿克苏站大气气溶胶中Al等元素在不同高度的谱分布呈单峰型,浓度最大值出现在4.7-7.0μm范围内,说明当地大气气溶胶颗粒主要来源于地表沙源。富集因子分析表明,阿克苏站和策勒站沙尘暴和扬尘天气的各地壳元素含量均高于浮尘和背景大气,而且能见度愈小,高出的比例愈大;各种沙尘天气发生时,均以亲地元素的浓度为最高。 相似文献
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Giuseppe Montana Luciana Randazzo Ilaria A. Oddo Mariano Valenza 《Environmental Geology》2008,56(2):367-380
Chemical, mineralogical and isotopic composition (34S/32S) analyses were carried out on “black crusts” developed on the old buildings of Palermo (Sicily) with the aim to distinguish
between natural and anthropogenic sulphur sources. Furthermore individual samples of total suspended particulate (TSP) were
collected and analysed in order to estimate the influence of air pollution on the decay process of calcareous stones in a
typical southern Mediterranean coastal environment. SEM/EDS analysis, X-ray diffractometry, IR spectroscopy and liquid chromatography
led to the compositional characterization of “black crusts” and airborne particulate matter in the city. Sulphur isotopic
compositions of gypsum-bearing crusts showed a prevailing contribution of anthropogenic sources (vehicle exhaust and other
combustion processes). Natural sulphur and/or sulphate sources (biogenic and/or sea-spray) were shown to play a secondary
role. These data can be considered a starting point for the determination of the rate of growth of “black crusts” in a coastal
Mediterranean urban environment like Palermo. In the future, they might be useful to local authorities for planning more efficient
maintenance action in order to slow as much as possible the rate of decay of the monumental heritage of the city. 相似文献
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The concentrations of organic carbon (OC) and elemental carbon (EC)in total suspended particle (TSP) were investigated at Ny-(A)lesund, Svalbard in a two-week campaign. The levels of OC and EC are 0.86 ±0.27 μgm-3 (mean±standard deviation) and 0. 19±0.10 μgm-3 , respectively. Back trajectory analysis of air masses arriving at Ny-(A)lesund reveals that long-range transport of polluted air play insignificant role in OC and EC levels, to which the potential influence of the local contamination were ascribed. The average OC/EC ratio is 5.41,suggesting the presence of the secondary organic aerosols. The estimated secondary organic carbon (SOC) in TSP is 0.59 μg/m3 , accounting for 64% of the total organic carbon. 相似文献
38.
为了减少地质灾害对隧道施工的影响,采用TSP203超前地质预报系统对隧道掌子面前方进行探测,提供超前地质预报,为后续施工提供指导。但是,在实际应用中出现了很多误报、漏报或者准确性太低的情况,这些问题往往是由于数据采集和数据处理中的不足带来的。通过规范的数据采集和合理的数据处理,可以减少这些不足的不良影响,从而提高TSP203系统在超前地质预报应用中的准确性。 相似文献
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兰州西固区TSP污染的预测及烟尘排放总量控制研究 总被引:2,自引:2,他引:0
以复杂地形上的平流扩散模式和高斯扩散模式相结合,首先预测了由于污染源排放量的变化所引起的2000年兰州西固区TSP污染状况的变化。然后提出了以A-P限制为基础的区域总体优化的总量控制方案,计算了兰州西固区烟尘的基础、平权、优化三种允许排放量及相应的削减量。其结果可为兰州西固区TSP污染的控制和治理提供理论上的依据和参考 相似文献
40.
Based on Total Suspended Particulates (TSP) observations of Tazhong, Tikanli, Kashi and Minfeng in 2009, combined wa- ter-soluble inorganic ion analyses, this paper studied the spatial and temporal distribution of TSP in the Tarim Basin and analyzed concentration characteristics. The results are as follows: (1) monthly average TSP concentrations shows a similar trend in Tazhong, Tikanli, Kashi and Minfeng with peak values in April-May and low values in November-December. As for the quarter average mass concentration trends, spring has the highest value, followed by summer and autumn, and winter is the lowest; (2) total annual concentration trend of water-soluble inorganic ions in TSP is as follows: Tazhong 〉 Tikanli 〉 Minfeng 〉 Kashi. SO4^2- concentra- tions are 58%, 50%, 54% and 51% of total ion concentration; Ca^2+ concentrations are 13%, 16%, 16% and 11%; Na^+ concentra- tions are 12%, 13%, 10% and 12% and Cl^- concentrations are 12%, 16%, 11% and 22%, respectively. Therefore, sulfate, calcium, sodium and chloride ions are the main inorganic components of TSP in the Tarim Basin; (3) the correlation coefficients of anions and cations in Tikanli, Minfeng, Kashi and Tazhong are 0.99, 0.99, 0.25 and 0.91, respectively; the average anion concentrations are 2.57, 2.12, 2.15 and 3.02 times the average cation concentrations, indicating that ions were unbalanced; (4) SO4^2-/NO3^- ratio is much larger than the ratio of coal-fired emissions SO4^2-/NO3^-, thus the impact of fixed emission sources in the four regions on the atmosphere is far greater than that of mobile emission sources. 相似文献