洪水计算的新进展——古洪水研究

尽管中国有悠久历史，但利用历史洪水展延洪水频率曲线以求稀遇设计洪水，仍感困难和不可靠，古洪水研究可得到数千年的大洪水资料。使洪水的考证期大为扩展，因而得以从根本上避免现行数字外延洪水顺频率曲的弊端，成果稳定可靠，为洪水计算工辟了一条新的途径，本文论述了古洪水研究的原理方法和我国四大河流应用古洪水研究的经验与成果。     

Urban Plant Diversity in Relation to Land Use Types in Built-up Areas of Beijing

Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field survey was conducted using the tessellation-randomized plot method to assess the plant species and functional traits variability in greenspaces across eight land use types (LUTs) in the built-up areas of Beijing, China. Results showed that the woody plants in the built-up areas of Beijing comprised 85 non-native species (57%), 21 pollen-allergenic species (14%), and 99 resistant species (67%). Residential areas, community parks and institutional areas had higher woody plant species richness than other LUTs. Native and extralimital native species were more widespread than exotic species. Proportions of species with resistances were low except for cold- and drought-resistance; consequently, a high intensity of management and maintenance is essential for survival of plants in this urban area. Caution should be exerted in selecting plant species with resistance to harsh conditions in different LUTs. Housing prices, distances from the urban center, years since the establishment of LUTs and greening rate were strongly correlated with the plant functional traits and species diversity. Urban forest managers should consider plant functional traits and LUT-specific strategies to maximize both forest and human health.     

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Assessing the applicability of conceptual hydrological models for design flood estimation in small-scale watersheds of northern China

Natural Hazards - The estimation of design flood is mainly focused on the peak flow and the volume, ignoring the underlying surface factor and flood rising and falling process. Three basic...     

High Performance Concrete and Its Typical Mixes

- With the modern development of chemical and mineral admixtures, it is now possible to produce much higher performance concrete than before. Higher performance does not only mean higher strength, but also better durability, lower risk of thermal cracking and higher dimensional stability etc. The three most effective admixtures for producing high performance concrete are superplastieizer, pulverized fuel ash and condensed silica fume. This paper outlines the properties of these materials and presents some practical guidelines for their usage.     

广域实时精密定位技术与示范系统完好性监测结构设计

对广域实时精密定位技术与示范系统进行了介绍,并对系统中完好性监测功能进行了定义。通过对完好性监测体系结构的研究,分析了本系统中完好性监测的基本流程。最后提出了广域实时精密定位技术与示范系统中,完好性监测功能的基本结构设计方案。     

太湖流域宜溧河地区水体水质状况及营养状态评价

宜溧河流域是太湖的主要集水流域,流域水体的水质状况及营养状态与太湖的水质状况与营养状态密切相关,本研究根据2000年12月14-15日以及2001年4月18-19日两次大规模的水质同步监测结果,对流域平原河网地区水体的水质状况及营养状态进行了系统综合的评价,评价结果表明：不管是平水期还是枯水期,河网水体的水质状况都较差,营养水平较高;在枯水期间,受多种因素的综合影响,水体的水质状况呈现恶化趋势,营养盐含量也有所升高。     

基于生物信息学及分子对接探讨胃食管反流病和肠易激综合征重叠症发病机制及中药组方预测

目的：探讨胃食管反流病（GERD）和肠易激综合征（IBS）重叠症的中医病机及病理机制,为中药组方提供理论引鉴。方法：通过DisGeNET 数据库和人类基因注释数据库及蛋白质-蛋白质相互作用（PPI）网络分析筛选出与IBS和GERD共同相关的关键靶点,并对其进行基因本体（GO）功能与京都基因与基因组百科全书（KEGG）通路富集分析。根据口服生物利用度≥30%、类药性≥0.18、度值筛选出与靶点相关的候选化合物,对度值排名前3位的靶点与每一种候选化合物两两之间计算分子结合能以验证可靠性。通过TCMSP寻找与候选化合物相关的中药,并筛选出度值≥4的中药做靶点-化合物-中药网络,对所筛选出的中药进行药性、归经、功效频数分析。结果：共获得60个关键靶点,GO功能分析显示其与20个生物过程,13个细胞成分,15个分子功能有关;其中有28个关键靶点可被匹配,共收集到50个候选化合物,度值≥4的中药有71味;共制作150对分子对接,结果显示,靶点与化合物间结合活性较强,预测准确性较高;中药频数统计结果显示,可作用到疾病靶点的中药药性多为寒性,药味多苦、甘,多归肝、肺经,功效种类以清热、补虚为主。结论：本实验通过生物信息学手段和药物规律分析为GERD和IBS重叠症的中医病机理论和中药组方治疗引入了现代分子实验层面的数据支持,为中医现代病机及组方理论研究提供了新的切入点。     

基于Matlab的井水位反演含水层体应变可视化系统的研制

基于反演含水层体应变的数学模型,在Matlab GUI界面下研发1款高效、便捷的体应变反演软件,实现了规定时间阈内连续体应变值和实时体应变曲线的一键获得功能。软件的用户界面操作简便,经实例验证,其运算速度和结果均可满足计算和分析需求。