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971.
A yearly maximum sea level simulator for Stockholm is presented. The simulator combines extreme sea level estimates and mean sea level rise projections into a joint probabilistic framework. The framework can be used, for example, to assess the risk that new structures placed at the current minimum allowed height above the sea level can become flooded in the future. Such assessments can be used to underpin future building free levels, which would be a great improvement over the much more arbitrary criteria in use today. Another strong point of the framework is that it can be used to quantify the influence of uncertainties in mean sea level projections, estimates of sea level extremes and future emission scenarios on the risk of flooding. For Stockholm mean sea level uncertainty is found to be much more important than extreme sea level uncertainty. The framework is also set-up to test adaptation measures. It is found that protections that are built once the mean sea level has risen above some given threshold can be very efficient. Lastly, the framework is embedded into a simple decision problem that can be used to calculate risk/reward ratios for land development as a function of height above today’s mean sea level.  相似文献   
972.
抽水对地壳形变观测影响的研究   总被引:2,自引:0,他引:2  
抽水引起地面沉降问题早已引起世界各国的关注,是目前世界上许多取用地下水的国家共同面临的严重环境保护问题。我国地面沉降研究工作的开展已有10多年的历史,主要方法是利用沉降模型进行模拟推测,其弊端较多。由于缺少地下水水位和地面沉降的实际观测资料,难以进行细致的研究.蓟县地震台进行地形变监测已有十几年的历史,在长期的地形变观测中,不仅能监视到抽水引起地面倾角的地变化(经换算可得地面垂直方向的变化),还能监视地面因抽水引起地面水平方向的变化.为具体研究人工抽水与地壳形变的关系进行抽水实验。  相似文献   
973.
曹建  施式亮  陈晓勇  李岩  曹华娟 《安全》2019,40(5):30-33,39
为有效控制与降低危化品管道运输风险,以国家安全生产法和危化品输送管道安全管理规定为基础依据,与我国危化品管道运输现状相结合,建立以危化品管道运输安全等级为目标层的评价指标体系后,基于层次分析法(AHP)理论与模糊数学综合评价法(FUZZY),构建其综合评价模型。通过实例验证表明,该模型对危化品管道运输安全等级的确立科学且有效,所得结论对于提升危化品管道运输安全等级有较好的理论和实践指导作用。  相似文献   
974.
Sun Y  Luo X  Wu J  Mo L  Chen S  Zhang Q  Zou F  Mai B 《Chemosphere》2012,89(4):445-451
Little data is available on the bioaccumulation of Dechlorane Plus (DP) in terrestrial organisms. Three terrestrial passerine bird species, light-vented bulbul, long-tailed shrike, and oriental magpie-robin, were collected from rural and urban sites in the Pearl River Delta to analyze for the presence of DP and its dechlorinated products in muscle and liver tissues. The relationships between trophic level and concentration and isomeric composition of DP in birds were also investigated based on stable nitrogen isotope analysis. DP levels had a wide range from 3.9 to 930 ng g−1 lipid weight (lw) in muscle and from 7.0 to 1300 ng g−1 lw in liver. Anti-Cl11-DP and syn-Cl11-DP, two dechlorinated products of DP, were also detected in bird samples with concentrations ranged between not detected (nd)-41 and nd-7.6 ng g−1 lw, respectively. DP preferentially accumulated in liver rather than in muscle for all three bird species. Birds had significantly higher concentrations of DP in urban sites than in rural sites (mean, 300 vs 73 ng g−1 lw). The fractions of anti-DP (fanti) were higher in birds collected in rural sites than in urban sites. Significant positive correlation between DP levels and δ15N values but significant negative correlation between fanti and δ15N values were found for birds in both urban and rural sites, indicating that trophic level of birds play an important role in determining DP level and isomeric profile.  相似文献   
975.
In this paper we synthesise the findings from the papers in this special issue on Organising productive science-policy interactions for sustainable coastal management. Lessons from the Wadden Sea. We first briefly discuss some relevant theoretical debates, and then present our main insights and lessons from the empirical evidence reported in the papers. We conclude the paper with suggestions for further research.  相似文献   
976.
In the present study the concentrations of cobalt, copper, iron, manganese, zinc were analysed and the speciation of copper and zinc performed, with a summer and winter sampling, for two areas in the Northern Adriatic Sea and crossing at the farthest zones of the Po river-sea water interface. Results show that when salinity increases the concentrations of all investigated metals (with the exception of cobalt) present some degree of biogeochemical cycling. Copper is the element whose dissolved phase has the highest importance in metal transport across the salinity gradient. Results of speciation analysis demonstrate that the presence of excess amounts (5-8 fold) of unbound ligands confers a buffering capacity for potential inputs of dissolved metals into the Northern Adriatic Sea. The speciation of both copper and zinc in the dissolved phase was dominated by organic complexation.  相似文献   
977.
978.
通过研究实际操作中汽包水位的变化趋势,对锅炉灭火后水位变化情况进行分析,得出锅炉灭火后汽包水位升降的3个阶段,指导实际操作。  相似文献   
979.
延迟焦化焦粉夹带的原因及应对措施   总被引:1,自引:0,他引:1  
详述了焦炭塔发生焦粉夹带的危害、原因及预防措施,描述了分馏系统焦粉的处理措施。  相似文献   
980.
成都市大气PM2.5中有机磷阻燃剂的污染水平及来源   总被引:2,自引:1,他引:1  
应用气相色谱-质谱联用仪定量分析成都市大气PM2.5中有机磷酸酯阻燃剂(OPEs)的质量浓度水平,讨论了其分布特征,并采用后向气流轨迹模型及相关性分析探析PM2.5中OPEs的来源.结果表明,成都市市区采样点大气PM2.5中Σ7OPEs年平均质量浓度为6.46 ng·m-3,郊区采样点为9.38 ng·m-3.受郊区废旧物质拆解产业和常年主导风向的影响,郊区采样点大气PM2.5中OPEs的质量浓度高于市区采样点(P=0.013).大气混合程度影响郊区和市区OPEs的分布,外源污染对成都市OPEs贡献小,OPEs质量浓度高低可能主要受采样点周围局地源的影响.  相似文献   
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