基于ArcGIS Engine的地质灾害信息管理与应用

以地质灾害风险信息管理与应用为例,运用AE技术实现多源灾害信息统一管理、快速提取、专题图输出,揭示了GIS技术在此领域应用的可行性和广阔前景。     

基于WMM2010地磁模型的微卫星姿态确定

概述了微卫星的特点和发展应用概况,简述了微卫星借助单个磁强计完成三轴姿态确定的原理;并以WMM2010模型为研究对象,介绍了确定卫星姿态的统计性方法;分析了几种不同截断阶数的地磁模型与地磁场真值的差异,指出对于定姿精度要求不高的中低轨道(数百千米)卫星,可将低阶模型作为磁场真值存储在卫星处理器中,有助于提高卫星定姿的实时性。     

真实地震情况下人群疏散特征与模拟演练的差异:2008年汶川地震监控录像的分析

真实地震情况下人群疏散特征与模拟演练的差异是应急疏散的统计物理研究中的一个关键问题.本文通过互联网收集和分析了2008年5月12日汶川MS8.0地震中一些记录到地震时人群疏散的监控录像.这些监控录像不仅为真实地震情况下人员疏散行为的研究提供了目前仍十分稀缺的实例.而且可用于约束紧急情况下人群疏散的统计物理模型.对条件相似的真实地震情况下和模拟演练情况下的疏散人数一疏散时间进行研究,发现出口处的疏散人数和疏散时间呈显著的非线性关系,这与通过模拟演练所得出的线性关系具有明显的差异.     

PI算法用于川滇-安达曼-苏门答腊地区7.0级以上强震危险性预测的回溯性检验

作为一个中长期地震预测方法,基于复杂系统统计物理的图象信息学PI算法近年来广受关注．针对7级以上强震成组和突发交替的川滇地区,考虑将与其构造和地震活动关系密切,且强震频发的安达曼-苏门答腊地区作为统一的强震预测研究区,使用PI算法进行MW7.0及以上预测ldquo;目标震级rdquo;的地震危险性分析．计算中使用了1973年以来的NEIC目录,采用10年尺度的地震活动ldquo;异常学习rdquo;时段和3年尺度ldquo;预测时间窗rdquo;,对预测效果进行了ROC检验．回溯性研究显示,PI预测效果较好,表明将川滇-安达曼-苏门答腊地区作为统一的7以上强震PI预测研究区在统计上具有合理性．从统计物理角度,研究区组合前后的各态遍历性曲线显示,组合后的研究区对PI的适用程度虽不优于单独考虑川滇地区,但优于安达曼-苏门答腊地区．PI图象显示,2008震前可能存在中长期尺度的ldquo;前兆性rdquo;地震活动异常．      

Nitrous oxide (N<Subscript>2</Subscript>O) emissions from a mesotrophic reservoir on the Wujiang River,southwest China

Aquatic ecosystems have been identified as a globally significant source of nitrous oxide (N₂O) due to continuous active nitrogen involvement, but the processes and influencing factors that control N₂O production are still poorly understood, especially in reservoirs. For that, monthly N₂O variations were monitored in Dongfeng reservoir (DFR) with a mesotrophic condition. The dissolved N₂O concentration in DFR displayed a distinct spatial–temporal pattern but lower than that in the eutrophic reservoirs. During the whole sampling year, N₂O saturation ranging from 144% to 640%, indicating that reservoir acted as source of atmospheric N₂O. N₂O production is induced by the introduction of nitrogen (NO₃ ^?, NH₄ ⁺) in mesotrophic reservoirs, and is also affected by oxygen level and water temperature. Nitrification was the predominate process for N₂O production in DFR due to well-oxygenated longitudinal water layers. Mean values of estimated N₂O flux from the air–water interface averaged 0.19 µmol m^?2 h^?1 with a range of 0.01–0.61 µmol m^?2 h^?1. DFR exhibited less N₂O emission flux than that reported in a nearby eutrophic reservoir, but still acted as a moderate N₂O source compared with other reservoirs and lakes worldwide. Annual emissions from the water–air interface of DFR were estimated to be 0.32 × 10⁵ mol N–N₂O, while N₂O degassing from releasing water behind the dam during power generation was nearly five times greater. Hence, N₂O degassing behind the dam should be taken into account for estimation of N₂O emissions from artificial reservoirs, an omission that historically has probably resulted in underestimates. IPCC methodology should consider more specifically N₂O emission estimation in aquatic ecosystems, especially in reservoirs, the default EF5 model will lead to an overestimation.     

Electro‐Catalytic Degradation of Phenol Organics with SnO2‐Sb2O3/Ti Electrodes

The effect of extraordinary degradation of phenol organics on the SnO₂‐Sb₂O₃/Ti electrode is investigated through experimental research and theoretical analysis. The phenol organics contained 4‐chloro‐phenol, 4‐bromo‐phenol, and 2‐iodo‐phenol. At a current density of 4 mA cm^–2 and an electrolysis time of 12 h, the degradation efficiency of the phenols was over 98% with a relatively short degradation time, whereas the degradation time of the PbO₂/Ti electrode surpassed 40 h while delivering 100% disposal efficiency. Therefore, the effectiveness of electrochemical (EC) oxidation by the SnO₂‐Sb₂O₃/Ti was superior to that of the PbO₂/Ti electrode. At the same time, the SnO₂‐Sb₂O₃/Ti had higher oxygen generation potential and lower electron consumption than the other electrodes. This was mainly due to the effect of the middle Sb₂O₃ layer, which due to its high porosity and good catalytic effect, contributed to a better catalysis than the SnO₂ part.     

The Upper Limit Size of Reservoir-Induced Earthquakes

We showed the relation between the magnitude of induced earthquake and the reservoir storage and dam height based on the global catalog from 1967 to 1989 compiled by Ding Yuanzhang （1989）. By multiplying reservoir storage with dam height, we introduced a new parameter named EE. We found that the cases with specific EE and magnitude do not exceed a limit. Based on the discussion of its physics, we called EE the equivalent energy. We considered this limit as the upper limit of magnitude for reservoir-induced earthquakes. The result was proved by the recent cases occurring in China. This size limitation can be used as a helpful consideration for reservoir design.     

长江中下游水阳江流域BZK0402孔多重地层划分及其冰后期海平面变化的沉积响应

[研究目的]开展水阳江流域标准孔BZK0402孔多重地层划分,探讨长江支流水阳江流域冰后期海平面变化的沉积响应以及古丹阳湖的成因和形成时代.[研究方法]以岩石地层为基础,在磁性地层和年代地层的双重约束下,对BZK0402孔进行多重地层划分.对比分析BZK0402孔和长江河谷、长江三角洲等邻区钻孔.[研究结果]BZK04...