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1984年10月26日22点22分19秒(格林威治时间)在治尔加塔尔(南天山)发生了5.9级地震。乌兹别克斯坦境内的费尔干纳实验场位于最活动的地震带,实验场的综合预报台网离这次地震的震中最近。 该台网综合观测了水文地质地震参数和形变测量参数、地球物理场和可以作为地震前兆的其它指标的变化。 多年的研究结果表明,在天山造山带M≥5的壳下地震和帕米尔—兴都库什M≥6的深源地震之前,都发生了水文地球化学异常和流体地球动力学异常。 流体地球动力学前兆:在奇米昂构造区利用Ⅺ、ⅩⅤ和OⅡ-Ⅰ号井观测了动态,这三口 相似文献
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Bredehoeft JD 《Ground water》2003,41(5):571-577
Today, models are ubiquitous tools for ground water analyses. The intent of this paper is to explore philosophically the role of the conceptual model in analysis. Selection of the appropriate conceptual model is an a priori decision by the analyst. Calibration is an integral part of the modeling process. Unfortunately a wrong or incomplete conceptual model can often be adequately calibrated; good calibration of a model does not ensure a correct conceptual model. Petroleum engineers have another term for calibration; they refer to it as history matching. A caveat to the idea of history matching is that we can make a prediction with some confidence equal to the period of the history match. In other words, if we have matched a 10-year history, we can predict for 10 years with reasonable confidence; beyond 10 years the confidence in the prediction diminishes rapidly. The same rule of thumb applies to ground water model analyses. Nuclear waste disposal poses a difficult problem because the time horizon, 1000 years or longer, is well beyond the possibility of the history match (or period of calibration) in the traditional analysis. Nonetheless, numerical models appear to be the tool of choice for analyzing the safety of waste facilities. Models have a well-recognized inherent uncertainty. Performance assessment, the technique for assessing the safety of nuclear waste facilities, involves an ensemble of cascading models. Performance assessment with its ensemble of models multiplies the inherent uncertainty of the single model. The closer we can approach the idea of a long history with which to match the models, even models of nuclear waste facilities, the more confidence we will have in the analysis (and the models, including performance assessment). This thesis argues for prolonged periods of observation (perhaps as long as 300 to 1000 years) before a nuclear waste facility is finally closed. 相似文献
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Relationship between structures of substituted indolic compounds and their degradation by marine anaerobic microorganisms 总被引：1，自引：0，他引：1
Degradation of selected indolic compounds including indole, 1-methylindole, 2-methylindole, and 3-methylindole was assessed under methanogenic and sulfate-reducing conditions using the serum-bottle anaerobic technique and marine sediment from Victoria Harbour, Hong Kong as an inoculum. Our results showed that indole degradation was achieved in 28 days by a methanogenic consortium and 35 days by a sulfate-reducing consortium. During degradation under both conditions, two intermediates were isolated, purified and identified as oxindole and isatin (indole-2,3-dione) suggesting that both methanogenic and sulfate-reducing bacteria use an identical degradation pathway. Degradation processes followed two steps of oxidation accomplished by hydroxylation and then dehydrogenation at 2- and then 3-position sequentially prior to the cleavage of the pyrrole ring between 2- and 3-positions. However, none of 1-methylindole or 2-methylindole was degraded under any conditions. 3-Methylindole (3-methyl-1H-indole, skatole) was transformed under methanogenic conditions and mineralized only under sulfate-reducing conditions. It is clear that methyl substitution on 1- or 2-position inhibits the initial attack by hydroxylation enzymes making them more persistent in the environment and posing longer toxic impact. 相似文献