基于GIS的保险防灾信息系统构建

从分析保险防灾业务的特点出发，提出利用MapGIS强大的二次开发功能构建保险防灾信息系统。作者结合自己的开发实践，比较全面的介绍了如何利用GIS技术来管理保险防灾业务的空间信息，并对这些关键的技术进行较全面阐述，对基于地理信息的信息系统的开发提供了许多有益的解决方案     

基坑开挖与土钉支护的数值模拟

运用FLAC程序对深基坑土钉墙支护设计进行了数值模拟,分析了边壁土体的变形大小和土钉应力分布,并与现场实测结果对比,得出基坑顶的水平位移值与实测值相差不大,并对差值进行了分析。在应力方面,改善了土体内应力集中的现象,从而制约了土体的变形。剪应力在支护结构和坡角处有集中现象,在坡角处较为严重。     

Energetic Particles Observed in the CUSP Region During a Storm Recovery Phase

In this paper we report energetic ion behavior and its composition variations observed by the Cluster/RAPID instrument when the spacecraft was travelling in the high latitude magnetospheric boundary region on the day of the 31 March, 2001, strongest magnetic storm in the past 50 years. The Dst index reached −360 nT at about 09:00 UT. During its early recovery phase, large amounts of oxygen and helium ions were observed; the ratio of oxygen to hydrogen in the RAPID energy range reached as high as 250%, which suggests that the observed energetic particles might be of magnetospheric origin. The observations further show that enhanced energetic electron fluxes are confined in a very narrow region, while protons have occupied a larger region, and heavy ions have been observed in an even larger region. The flux of energetic electrons show a slight enhancement in a region where the magnetic field magnitude is around zero. These observed energetic ions could be quasi-trapped by the current sheet in the stagnation region of the cusp.     

The Magnetospheric cusps: A Summary

The polar cusps of the magnetosphere are key regions for the transfer of mass, momentum, and energy from the solar wind into the magnetosphere. Understaning these key regions and the dynamical interactions that occur there are fundamentally important to determining the physical nature of the magnetosphere. In this paper we try to summarize many of the conclusions reached in the papers of this special issue emphasizing the present concepts and definition of the cusp, what variations could be temporal structures and what could be spatial structures. We address the need for further measurements and the role of present and planned projects to address these needs.     

1996-2022年黄河三角洲行水河口岸线稳定性研究

黄河清八汊现行河口自改汊以来发生了巨大变化,监测其岸线变化,探讨其稳定程度对海岸带可持续发展以及海岸带韧性评估具有重要意义。本研究利用GPS、GIS、RS技术从1996—2022年黄河三角洲行水河口的220幅遥感影像中推断出年平均海岸线位置,同时根据行水河口摆动次数划分为5个阶段,并以此为基础对海岸线变迁及其稳定性进行定量分析。结果表明：行水河口岸线长期处于动态变化过程中,整体呈淤进状态,各岸段岸线时空变化特征不同,最大侵蚀（-73.89m/a）区出现在两丁坝之间,最大淤积（393.20m/a）区出现在河口区附近。研究区90%的岸线表现为较强淤积至严重淤积,稳定性指数由两丁坝之间（0.135）、2007年出汊前旧河口（0.068）、2007年出汊后新生河口（0.006）依次降低。入海水沙量、河口位置变迁以及沿岸输沙是影响岸线稳定性出现时空差异的主要原因。     

Role of the warming trend in global land surface air temperature variations

Global warming and its climatic and environmental effects have mainly been investigated in terms of the absolute warming rate. Little attention has been paid to the contribution of absolute warming rate to variability on various time scales of surface air temperature(SAT), which may be a more direct index for measuring the ecoclimatic effect of warming trend. The present study analyzed the role of secular warming trend in the variations of global land SAT for 1901–2016. Less than one-third of annual SAT variations were contributed by the warming trend over large parts of the globe generally. The ratios were up to two-thirds over eastern South America, parts of South Africa and the regions around the southwestern Mediterranean and Sunda islands where the absolute warming rate was moderate but the endemic species were undergoing exceptional loss of habitat. The ratios also exhibited smallest seasonal difference over these regions. Therefore, the ratio of the warming trend to the SAT variations may be a better measure compared to the absolute warming rate for the local ecoclimate. We should also pay more attention to the regions with high ratio, not only the regions with the high absolute warming rate.     

湿法处理荧光法测定空气中的微量铀

用过滤集尘法过滤的空气取样滤膜采用冷浸消化处理,在硝酸介质中UO22+与高效抗干扰的荧光增强剂络合成具有高荧光效率的单一络合物,该络合物受波长为在337.1nm的紫外激光脉冲辐射产生明亮的绿色荧光,可直接用标准加入法测定其铀的含量。研究了pH对其测定条件的影响,实验表明pH最佳值为4.5,测定结果相对偏差小于5%,回收率为94.5%~100%。此方法操作简单易行,分析结果稳定可靠。     

盐胁迫下梭梭幼苗膜脂过氧化和保护酶活性

使用0、50、100、200、350、500 mmol/L NaCl处理梭梭幼苗,分三次取样,并测其相应指标,结果表明梭梭幼苗细胞膜透性在10天时保持稳定;当胁迫到20天、30天时,同化枝膜透性随盐浓度的增加及胁迫时间的延长逐渐增加.整个试验过程中,丙二醛含量逐渐增加,但前期增加幅度不大,后期梭梭幼苗同化枝的丙二醛含量在NaCl胁迫30天时为2.569 μmol·g-1.SOD和POD活性在整个试验过程中相对于对照而言整体呈增加趋势,但在前期增加得较快,后期较慢.CAT活性在整个过程中则一直呈增加趋势.     

LAS在西北干旱区荒漠均匀下垫面的观测研究

利用“古浪非均匀近地层观测试验”的仪器平行对比观测部分试验数据,首先分析荒漠均匀下垫面大孔径闪烁仪(Large Aperture Scintillometer,LAS)光径线上等间距架设的4台涡动相关仪(Eddy Covariance System,EC)观测的摩擦速度和感热通量的一致性.然后,基于4种不同下垫面建立稳定度普适函数分析,利用4台EC观测摩擦速度平均值,计算了LAS观测区域的感热通量,进而比较了LAS和EC两者观测值的差异.结果表明,4台EC观测的摩擦速度与感热通量一致性好,摩擦速度的差别＜10％,感热通量的差别在10％左右.4种稳定度普适函数计算的LAS区域感热通量在白天、夜晚与EC观测平均值变化趋势一致,但计算值偏大;TAG (Thiermann and Grassl)稳定度普适函数计算值与EC观测平均值较接近.其主要原因除不同下垫面试验所得稳定度普适函数的差异外,Kipp&Zonen LAS所测感热通量的系统性偏高不可忽视.     

铁岭莲花湖湿地湖心岛建设探讨

为解决人为活动对城市湿地公园内鸟类的影响,对铁岭莲花湖湿地公园湖心岛建设进行调查分析,湖心岛建设在保护湿地鸟类资源及丰富湿地景观多样性等方面起到了重要作用。根据城市湿地公园建设理念,提出了湿地公园中湖心岛建设的原则,初步探讨了湿地湖心岛建设过程中的基础填筑、岛上生物栖息地建设及岸边护坡等关键技术方案。