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41.
王涛  李杨  周勇  吕庆  刘大炜 《岩土力学》2011,32(Z2):407-412
磷石膏尾矿库是以磷石膏渣堆积起来形成的尾矿库,其安全问题一直是磷化工企业及安全生产管理部门非常关心的问题。根据《尾矿库安全监督管理规定》,尾矿库工程在设计阶段应该编写安全专篇,需要对尾矿库及尾矿坝稳定性、尾矿库防洪能力及排洪设施和安全观测设施的可靠性进行充分论证。3个方面的内容紧密联系,其是否安全可靠决定着尾矿库是否安全运行。针对磷石膏尾矿库的安全专篇问题,分析了专篇中的关键技术内容,对防洪计算、稳定性计算和安全监测分析等方面的本质问题进行了探讨,并将这三者作为一个系统进行分析总结。通过对湖北某磷石膏尾矿工程安全专篇的编写与分析,对具体的技术方法给出了说明。目前尾矿库工程安全问题受到了广泛的关注,其结果提供了比较完整的具体经验,采用的方法和得出的结论对相关工程可以起一定的借鉴作用。  相似文献   
42.
The Slumgullion landslide in the San Juan Mountains of southwestern Colorado has been moving for at least the last few hundred years and has multiple ponds on its surface. We have studied eight ponds during 30 trips to the landslide between July 1998 and July 2007. During each trip, we have made observations on the variability in pond locations and water levels, taken ground‐based photographs to document pond water with respect to moving landslide material and vegetation, conducted Global Positioning System surveys of the elevations of water levels and mapped pond sediments on the landslide surface. Additionally, we have used stereo aerial photographs taken in October 1939, October 1940 and July 2000 to measure topographic profiles of the eight pond locations, as well as a longitudinal profile along the approximate centerline of the landslide, to examine topographic changes over a 60‐ to 61‐year period of time. Results from field observations, analyses of photographs, mapping and measurements indicate that all pond locations have remained spatially stationary for 60–300 years while landslide material moves through these locations. Water levels during the observation period were sensitive to changes in the local, spring‐fed, stream network, and to periodic filling of pond locations by sediment from floods, hyperconcentrated flows, mud flows and debris flows. For pond locations to remain stationary, the locations must mimic depressions along the basal surface of the landslide. The existence of such depressions indicates that the topography of the basal landslide surface is irregular. These results suggest that, for translational landslides that have moved distances larger than the dimensions of the largest basal topographic irregularities (about 200 m at Slumgullion), landslide surface morphology can be used as a guide to the morphology of the basal slip surface. Because basal slip surface morphology can affect landslide stability, kinematic models and stability analyses of translational landslides should attempt to incorporate irregular basal surface topography. Additional implications for moving landslides where basal topography controls surface morphology include the following: dateable sediments or organic material from basal layers of stationary ponds will yield ages that are younger than the date of landslide initiation, and it is probable that other landslide surface features such as faults, streams, springs and sinks are also controlled by basal topography. The longitudinal topographic profile indicated that the upper part of the Slumgullion landslide was depleted at a mean vertical lowering rate of 5.6 cm/yr between 1939 and 2000, while the toe advanced at an average rate of 1.5 m/yr during the same period. Therefore, during this 61‐year period, neither the depletion of material at the head of the landslide nor continued growth of the landslide toe has decreased the overall movement rate of the landslide. Continued depletion of the upper part of the landslide, and growth of the toe, should eventually result in stabilization of the landslide. Published in 2008 by John Wiley & Sons, Ltd.  相似文献   
43.
Chlorophyll pigments (CHL), primary productivity (PP) and particulate nitrogen (Np) in relation to several environmental factors were monitored during planktonic colonization of an aquaculture pond (Layo, Côte d'Ivoire). How interactions between the organisms are established in an initially azoic environment were investigated. From March, 15 (D1) to March, 31 (D16), the system transformation went through three stages. First, a precolonization by heterotrophic microbial community from D1 to D2 (Np < 1 m maximum at D2: 243 mg m–2; CHL around 0). Then, a pioneer microalgal community developped from D3 to D7 (maximum CHL on D6: 19 mg m–2; PP: 1.0 g C m–2 d–1) with a significant contribution of picoplankton (CHL and PP < 3 m: 33 and 23% of the total, respectively). Finally, a second microalgal colonization was noticed from D9 to D12 (maximum CHL: 55 mg m–2, PP: 2.8 g C m–2 d–1), largely dominated by nanoplankton (CHL and PP > 3 m: 95 and 99% of the total, respectively). Overall, photosynthetic activity appeared to be closely linked to algal biomass. The study of autotrophic biomass and activity in different size classes in relation to the other parameters allowed us to precise the origin of the biomass fluctuations. The first bloom appeared to be controlled by selective grazing on small algae. The second algal development ended when N requirement represented at least 69% of N supply (in the N — NH4 form). This control was enhanced by the appearance of rotifers, leading to a more complex equilibrium.  相似文献   
44.
A hydrological simulation in the Huaihe River Basin(HRB) was investigated using two different models: a coupled land surface hydrological model(CLHMS), and a large-scale hydrological model(LSX-HMS). The NCEP-NCAR reanalysis dataset and observed precipitation data were used as meteorological inputs. The simulation results from both models were compared in terms of flood processes forecasting during high flow periods in the summers of 2003 and 2007, and partial high flow periods in 2000. The comparison results showed that the simulated streamflow by CLHMS model agreed well with the observations with Nash-Sutcliffe coefficients larger than 0.76, in both periods of 2000 at Lutaizi and Bengbu stations in the HRB, while the skill of the LSX-HMS model was relatively poor. The simulation results for the high flow periods in 2003 and 2007 suggested that the CLHMS model can simulate both the peak time and intensity of the hydrological processes, while the LSX-HMS model provides a delayed flood peak. These results demonstrated the importance of considering the coupling between the land surface and hydrological module in achieving better predictions for hydrological processes, and CLHMS was proven to be a promising model for future applications in flood simulation and forecasting.  相似文献   
45.
舟山虾塘纹藤壶种群结构研究   总被引:1,自引:0,他引:1  
应用挂板试验,研究了挂板浸水时间、挂板角度和对虾养殖塘内外环境差异等因素对附着于挂板上纹藤壶种群结构的影响.  相似文献   
46.
室外采用玻璃缸装置研究了抚仙湖常见的9种沉水植物氧化塘对澄江县污水厂尾水营养盐的去除效果及机制.结果表明:氧化塘中沉水植物的光合作用导致水体较高的DO和pH值,从而提高氧化塘总氮和总磷的去除率,但沉水植物叶片的腐烂分解则提高了水体氮磷的含量.沉水植物氧化塘对总氮和总磷的去除率分别介于19.44%-64.71%和28.13%-98.33%.沉水植物的直接吸收对总氮和总磷量去除的贡献比较低,占氧化塘总氮和总磷量的0.26%-1.54%和0.47%-1.77%.沉水植物氧化塘内DO、pH变化,促进了氮的降解及氧化还原分解,使其对氮的去除占氧化塘总氮量的30.71%-65.25%,而磷的去除则主要通过化学沉淀及基质吸附,占氧化塘总磷量的73.37%-93.34%.最终,选出蓖齿眼子菜、苦草、黑藻、金鱼藻和光叶眼子菜对氧化塘中氮磷具有较高的去除率.  相似文献   
47.
本文以丹江口水源区某磁铁矿尾矿库为例,采用高密度电法对尾矿库进行了三维电阻率结构探测,圈定了尾矿砂分布范围,实现了尾矿体三维地球物理建模,查明了尾矿库内部结构特征,通过电阻率差异圈定了4处重金属元素聚集区.验证了拟三维高密度电法在尾矿库三维结构探测中的可行性,为研究尾矿库内部污染物运移机理和污染防治提供了一种有效的技术手段.  相似文献   
48.
对虾病毒病与化学需氧量相关关系研究   总被引:19,自引:0,他引:19  
通过对虾池内主要环境因子与对虾病毒病相关关系的研究,发现虾池内化学需氧量(COD)太高是诱发对虾病毒病暴发流行的主要环境因子之一。利用多级S型净化池可以大幅度消除水体中的COD,有效预防对虾病毒病的暴发流行。  相似文献   
49.
虾池长竹蛏肥满度的研究   总被引:2,自引:0,他引:2  
王云  郑升阳 《台湾海峡》2001,20(Z1):57-59
本文作者于1997年4月至1998年3月期间,对幸福洋垦区虾池生长的长竹蛏进行了周年肥满度测定研究.结果表明长竹蛏5~9月份较肥,肥满度在60%~80%之间,11月至翌年4月份较瘦,肥满度在55%~47%之间;根据肥满度的测定,长竹蛏的繁殖期为6~8月份.  相似文献   
50.
移植大叶藻提高池养对虾产量的研究   总被引:6,自引:0,他引:6  
本实验首次用移植的方法在虾池内栽培大叶藻。结果表明,大叶藻可以净化虾池水质,改善虾池底质条件,丰富了饵料生物,促进了对虾的生长,提高了产量,每亩虾池的产量提高26.6%,纯利润提高190.5%。文章讨论了提高产量的原因。  相似文献   
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