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利用滤波分析法对山东泰安地震台重力固体潮观测的分析表明，重力观测中存在大量高频扰动信号.通过与气象观测实况资料的对比发现，这些异常扰动信号除了受台风等热带气旋影响外，还明显与“冷空气”过境等区域强对流天气有关. 对泰安台JCZ-1甚宽频带地震仪观测资料的频谱分析和滤波处理进一步表明，区域强对流天气及台风对重力仪的影响频段均在1—8 s范围内，其中2—6 s区间影响最为显著； 强对流天气过程触发的扰动信号范围可以在1—16 s，但8 s后扰动信号对重力仪观测基本不造成影响，即重力仪对高频扰动信号的响应存在8 s的截止周期.JCZ-1甚宽频带地震仪的波谱分析还反映出扰动信号的动态特征，即强对流天气产生的扰动信号在发展、传播过程中，首先出现的信号频率较高，随着时间推移信号逐渐向低频演化，揭示了干扰信号传播的多普勒效应以及扰动信号激发源的移动特性. 相似文献
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济南市玉符河多水源回灌岩溶水水质风险评价 总被引：1，自引：1，他引：0
济南以泉城而闻名，保泉和供水安全问题是其面临的巨大挑战，利用多水源进行岩溶水回灌是解决问题的有效措施之一，但是补给水源水质相对岩溶水而言较差，回灌到地下可能存在一定健康和环境风险，需要对回灌系统的水质进行风险评价。本文对比地下水质量标准和地下水水质背景值，重点选择地表源水超标和劣于背景值的风险源监测指标，借鉴澳大利亚含水层补给管理指南，对玉符河多水源回灌岩溶含水层工程运行期的水质风险进行评价。2015年对黄河水、卧虎山水库两种水源多次回灌期间的源水、孔隙水和岩溶水的22项指标进行水质监测和指标分析，风险残余评价结果表明黄河水回灌补源期间，平均浊度的标准指数源水是1.4，孔隙水1.7，岩溶水0.93，硫酸盐平均含量的标准指数源水是0.93，孔隙水0.9，岩溶水0.73，氯离子虽没有超过地下水III类标准，但是在源水中含量是地下水含量的2倍多；卧虎山水库水回灌补源期间，平均浊度的标准指数源水是2.4，孔隙水1.1，岩溶水0.43，硫酸盐平均含量的标准指数在源水0.75，孔隙水0.84，岩溶水0.66，氨氮的平均含量的标准指数源水1.14，孔隙水1.47，岩溶水1.35。因此，浊度、硫酸盐和溶质在裂隙岩溶含水层迁移较快为两种水源玉符河回灌补源工程的共同高风险项和关键控制点。此外，黄河水补源还需注意盐度，卧虎山水库水补源还需控制营养物的污染风险。基于以上评价，还提出了限制回灌量占区域岩溶水资源量比例等建议。 相似文献
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基于日本K-NET和KiK-net台网的4 695条俯冲带板内地震记录,采用最小二乘法对阻尼修正系数（DMF）的几何均值进行关于阻尼比和谱周期的回归拟合,分场地类别建立了考虑阻尼比和谱周期的竖向加速度谱DMF模型。为探究震源、路径和场地效应对该模型残差分布的影响,采用随机效应模型将残差分离得到各类残差及相应的残差标准差,在此基础上进行DMF模型残差分析。研究结果表明,DMF可以采用阻尼比对数值的三次多项式、周期对数值的四次多项式来模拟。由于规范设计反应谱并非针对某一特定地震,规范提出的DMF模型并不包含震源和路径参数,但事件间和事件内残差关于矩震级、断层距离和断层深度的分布表明,在给定地震事件下,包含地震动参数的DMF模型将会改善模型的预测能力。 相似文献
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Yang Zhou Tao Wang Xiaomei Gao Likun Xue Xinfeng Wang Zhe Wang Jian Gao Qingzhu Zhang Wenxing Wang 《Journal of Atmospheric Chemistry》2009,64(2-3):107-127
Near real-time measurements of PM2.5 ionic compositions were performed at the summit of the highest mountain in the central-eastern plains in the spring and summer of 2007 in order to characterize aerosol composition and its interaction with clouds. The average concentrations of total water soluble ions were 27.5 and 36.7 μg?m?3, accounting for 44% and 62% of the PM2.5 mass concentration in the spring and summer, respectively. A diurnal pattern of SO 4 2- , NH 4 + and NO 3 - was observed in both campaigns and attributed to the upslope/downslope transport of air mass and the development of the planetary boundary layer (PBL). The average SO2 oxidation ratio (SOR) in summer was 57% (±27%), more than twice that in spring 24% (±16%); the fine nitrate oxidation ratio (NOR) was comparable in the two seasons (9?±?6% and 11?±?10% in summer and spring, respectively). This result indicates strong summertime production of sulfate aerosol. A principal component analysis shows that short-range and long-range transport of pollution, cloud processing, and crustal source were the main factors affecting the variability of the measured ions (and other trace gases and aerosols) at Mt. Tai. Strong indications of biomass burning were observed in summer. Cloud scavenging rates showed larger variations for different ions and in different cloud events. The elevated concentrations of the water soluble ions at Mt. Tai indicate serious aerosol pollution over the North China plain of eastern China. 相似文献
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2009年3月济南市发生严重CO中毒事件,中毒人数达78例,中毒患者绝大部分出现在15日夜间至16日早晨,具有暴发性特征。对CO中毒事件发生期间的天气形势、气团性质和气象要素等进行了分析。结果表明:此次CO中毒事件发生在一次冷空气过后天气异常转暖的过程中;气团干暖、中低层大气层结稳定;气温呈明显大幅持续升温,气压呈现大幅持续下降等特征;弱风速时段与中毒人数的激增时段相吻合。分析影响此次事件的不良气象条件主要有:500 hPa暖脊的东移发展,引导我国西北地区干燥暖气团东移控制济南地区,造成气温、气压剧烈变化,导致空气密度显著降低,使济南较长时间处在低密度气团中,严重影响室内的自然通风和烟囱的抽吸效应,造成室内CO积聚引发中毒事件;夜间在弱风速与低密度气团对室内通风、烟囱抽吸效应产生的双重负面作用,是引发中毒人数激增的重要原因。 相似文献
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利用双差定位方法对2017年2月~2018年5月长岛震群进行重定位, 根据重定位结果计算长岛震群地震集中活动区域b值在深度上的变化分布。 结果显示: 长岛震群重定位的结果主要表现为北、 南两个地震活动区域。 北部地震活动区域的地震数量多, 时间跨度长; 南部地震活动区域的地震数量较少, 形成时间较晚, 震源深度主要集中在地壳深度4~25 km之间; 长岛震群北、 南两个地震活动区域的b值总体上均随深度增大而减小, 在8.5 km深度左右均存在转折上升的情况。 长岛震群b值的深度变化特征表明, 其应力主要受围岩静压力影响, 受断裂活动影响较小。 相似文献
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More and more deep-seated long submarine tunnels are under construction, which greatly promotes the development of tunneling technology. The complex geological conditions and frequent geological disasters have become great challenges during submarine tunnel excavation. Among them, casualties and economic losses caused by water inrush are on the top levels in all kinds of tunnel geological disasters. Escape routes after water inrush from the working face during submarine tunnel excavation are investigated and optimized in the present study. Numerical simulations are performed using the FLUENT software to probe water flow characteristics after inrush. Two common cases of water inrush during double-line submarine tunnel excavation are researched. The variation rules of velocity and pressure in the tunnels after inrush are analyzed and discussed. The optimized escape routes are achieved. Finally, the water movement laws after inrush from the working face under different excavation situations are further discussed by comparing the two case studies. Water inrush of high velocity occurs on one working face of the double-line submarine tunnel, and the research results are as follows: (1) The velocity close to the tunnel side wall is the minimum, while it is the maximum in the middle position. (2) The pressure changes greatly at the intersection area of the cross passage and the tunnels. (3) The velocity and pressure nearby the working face without water inrush are both small. (4) The velocity at the high location of the cross passage is relatively small. 相似文献
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Countermeasures of heavy metal pollution 总被引：2，自引：0，他引：2
This article gives a review on heavy metal pollution prevention and control,and it also discusses heavy metal pollutant discharge,prediction and evaluation of environmental impact,and pollution prevention and monitoring. 相似文献