Evaluating the effect of active ions on the early performance of soft clay solidified by modified biomass waste-rice husk ash

Acta Geotechnica - Soft clay generally cannot be directly used as subgrade material due to its poor engineering characteristics. The application of rice husk ash (RHA) for the solidification of...     

东山湾表层沉积物中8项化学要素的地球化学特征

本文根据1988年泰山湾调查资料,对该湾表层沉积物中有机质、重金属等8项化学要素进行了地球化学研究.结果表明,该湾表层沉积物的化学成分主要来源于(?)江径流携带的陆源物质,其分布呈北部和西部高,并向东南部递减的趋势。潮流是影响该湾化学要素分布的重要因素.有机质与多数元素有明显的正相关.污染物质含量较低.     

东山湾海水盐度,温度和溶解氧的分布特征

1988年5月、8月、11月和1989年2月东山湾海水的盐度范围分别为20.81～33.89、30.43～34.24、26.76～30.59和30.27～31.57;水温范围分别为23.4～25.0、22.5～30.8、18.1～20.7和14.5～17.3℃;溶解氧体积分数分别为(4.12～4.91)×10~(-3)、(3.50～5.10)×10~(-3)、(5.21～6.68)×10~(-3)和(5.64～6.00)×10~(-3);氧饱和度分别为85.1%～104%、73.3%～116%、99.6%～124%和102%～104%。春、夏季东山湾受高盐外海水的影响明显,其中夏季可能还受到上升流的影响.秋季浮游植物大量生长和繁殖,成为溶解氧含量和氧饱和度的主要影响因素。     

Temporal trend in surface water resources in Tianjin in the Haihe River Basin,China

Considering the highly stochastic nature of the hydrological process, wavelet transform was used to analyse the characteristics, trends and causes of variations in annual run‐off (1917–2006) into Tianjin in the Haihe River Basin. Run‐off was steadily declining due to climate change and human activity and a significant decrease in run‐off along the time series was discovered around the 1960s; however, the change in precipitation was insignificant. The time series of run‐off was heavily influenced by a nonlinear feature and mainly influenced by the natural climate before the 1960s, but after the 1970s the change remained steady, with an annual run‐off that fluctuated between 0·2 and 48·4 mm and was maintained at a low level (9·3 mm). The main cause of the run‐off decline in the 1960s was that more than 1900 reservoirs with a total holding capacity of up to 83 mm were constructed in the upper and middle reaches, which controlled 85% of the total run‐off. These projects have played an active role in the reservoir action and water conservation since they were implemented. At the beginning of the 1980s, the demand for water resources increased with the rapid growth of the population and the large‐scale development of industry and agriculture in the Haihe River Basin, which caused a reduction in run‐off into Tianjin. Overall, the hydrological effects of water storage projects regulating river run‐off were beneficial to flood control, but might cause a serious reduction in river run‐off into Tianjin and the lower reaches of the basin. In addition, a decrease in annual precipitation and changes in temperature in Northern China have also had an adverse effect on natural run‐off, which caused a greater decline in water resources, but this did not have a powerful influence on the overall decline in the run‐off. Copyright © 2011 John Wiley & Sons, Ltd.     

河道信息系统关键技术的研究

介绍了长江河道信息系统研制背景、系统主要功能，对断面计算、槽蓄量计算及分析过程可视化等关键技术问题进行了研究。     

南大线金矿床控矿劈理带

南大线金矿床为劈理带控制，发育在燕山期岩浆岩中，研究控矿劈理带的一系列特点有助于找矿勘探和矿山地质工作。     

中性大气折射的映射函数

在球对称大气模型下，我们导出了与余误差函数形式相联系的中性大气折射改正的母函数，并进一步讨论了它的几种数学展开形式。由此方法建立的映射函数可以对各类大气模型直接进行参数拟合。     

广州中心城区基本医疗服务等级区域分布及其特征

以广州市最新一轮行政区划结果与医疗机构相关数据为基础,运用ARCGIS和SPSS软件,通过构建基本医疗服务优势度模型,对3项子指标(距离、质量、频率)在各个优势度等级区域进行对照分析.发现广州中心城区基本医疗服务等级区域分布具有如下特征:以老城区(越秀区、荔湾区、海珠区)组成团块状的高优势度区域为中心,优势度分值自中心向外围区域呈环状递减,且优势度高分值区域有向市区东部及北部延伸的趋势.基本医疗服务等级区域指标具有如下特征:①极高值区、高值区与极低值区3项子指标得分均衡;②中高值区、中值区和中低值区存在质量低下型特征,低值区尤甚:③在基本医疗服务良好区域,区域内医疗服务条件差异显著,具有距离低下型特征.