共查询到19条相似文献，搜索用时 734 毫秒
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针对目前主要的房屋材料--砖,进行了一系列室内模拟降雨径流实验,考察了不同污染物浓度、不同流量对实验结果的影响.结果表明:原水浓度越小,砖吸附径流污染物的效果越好;降雨强度越大,径流污染物削减率越好. 相似文献
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《绵阳师范学院学报》2016,(11):84-90
地表径流是引起坡面土壤和养分流失的主要动力,寻求有效途径对降雨径流进行科学预测,是陕南地区农业面源污染防治的基础.本文选取后沟小流域8个不同坡度和面积的径流小区,结合2011-2012年汛期的6场降雨产流的实测数据,评价陕南地区坡耕地基于SCS-CN模型的适用性,并考虑降雨量影响的基础上对径流曲线数CN和初损系数Iα进行修正.结果表明,陕南地区小流域坡耕地初损参数λ为0.10.4.随着Iα的变化对CN进行修正,确定CN值为58.选取的8个径流小区中,利用SCS-CN模型的模拟效果较好,径流量模拟值变化趋势与实测值一致,降雨径流量模拟值与实测值进行相关分析,计算得到两者的相关性均达到极显著相关.6场降雨事件径流模拟值与实测值分别为8 082.3 L和7 419.8 L,相对误差为8.8%.该研究结果可为陕南地区降雨径流预测及面源污染防治提供参考. 相似文献
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南方丘陵地区降雨径流和泥沙输出特征 总被引：1，自引：0，他引：1
张玉珍 《福建工程学院学报》2006,4(3):323-326
在南方丘陵地区选择了2个小流域。进行野外9场降雨事件径流量、泥沙量随时问变化的试验。结果表明：受季节差异影响，不同月份径流量差异明显；低强度的降雨，当降雨过程停止后，径流流量反而有增大的趋势，强度较大的降雨。在中间时段降雨停止后。径流流量仍保持在一个稳定的值；在连续的低强度降雨后土壤含水量已经接近饱和，当遇到大强度的降雨后，地表径流在径流中所占比例较大；降雨量与悬浮泥沙含量相关程度较高。最大悬浮泥沙含量出现时间明显落后于径流流量出现峰值的时间。下降幅度要比径流流量下降幅度大。 相似文献
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田运林 《临沂师范学院学报》2010,32(3):47-50
通过对延庆县上辛庄径流试验站两年监测数据的分析,结果表明,植被覆盖度的提高可以明显抑制径流、土壤的流失强度,并且可消弱坡度、降雨对水土流失的影响程度．同时,30％的植被覆盖可能是该区能有效控制水土流失的临界值;污染物的流失强度随植被覆盖度的变化规律与径流与植被覆盖度的变化规律一致,即随着植被覆盖度增加而降低,说明植被措施对污染物流失的控制主要是通过减少径流泥沙而起作用的,但植被措施对不同污染物的抑制效果存在差异． 相似文献
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《赣南师范学院学报》2020,(3):104-107
机场建设属点状型工程且具有扰动面积大等特点,开展水土流失实地监测存在诸多困难.本文以赣州黄金机场扩建工程为例,通过选择各防治分区汇水出口作为监测点,于降雨期间测定各出口地表径流流速和流量,采用浊度仪测定径流携带的土壤流失量.监测结果表明:2018年,项目区产生径流87.3万m3、径流系数为0.89;项目区因扰动地表等建设活动产生土壤流失1,524.8 t、侵蚀模数为2,609.1 t km3、径流系数为0.89;项目区因扰动地表等建设活动产生土壤流失1,524.8 t、侵蚀模数为2,609.1 t km(-2)a(-2)a(-1).以地表径流汇集出口作为监测点并采用相应的观测方法,对监测实践具有一定的指导意义. 相似文献
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本文阐述了垃圾渗滤液的污染特征和处理方法,总结了渗滤液污染物浓度高、持续时间长、流量小且不均匀、水质变化大等特征,厌氧-好氧生化处理效果明显,可达GB16889-1997一级排放标准. 相似文献
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多水塘湿地系统是我国特有的农业微景观结构，通过对巢湖六叉河小流域多水塘水生植被群落的组成和生物量及其对面源污染的截留作用进行研究，结果表明多水塘湿地系统内共有8种水生植被、5个优势群落，水生植被分布面积占多水塘系统总面积的12．6％；水生植被对氮磷面源污染负荷的截留率分别为12．0％和6．7％． 相似文献
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介绍了一种利用MBER土壤固化剂作为建筑材料的塑性施工工艺,并分析了利用该工艺施工的土壤固化剂蓄水装置的水体水质状况.试验于2012年7月收集集流面径流,并进行后期贮存.采集的集流面和窖水水样的监测指标包括浊度、COD、总氮、硝酸盐和氨氮.结果表明,集流面径流中污染物含量呈现出随降雨历时增加而逐渐减小的变化趋势,因此降雨初期阶段的雨水应该弃用.贮存窖水中硝酸盐浓度呈现随贮存时间增加而逐渐增大的变化趋势,而其余污染物浓度均呈现随贮存时间增加而逐渐减小的趋势.上述指标的监测结果均未超过国家饮用水卫生安全标准.研究表明该种装置可用于提供家庭用水. 相似文献
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许长谭 《临沂师范学院学报》2001,23(4):9-12
采用Holstein-Primakoff变换、相干态表示；含时微扰原理和多重标度方法，研究了Aharonov-Bohm(A-B)磁通对一维铁磁链中的磁隙孤子产生的影响，得到了在A－B磁通影响下的磁隙孤子的峰值、宽度、能量和自旋空间排列。 相似文献
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Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiveness were investigated in this open-air pot experiment. Cyperus rotundus was transplanted into soil contaminated with diesel at concentrations of 1 000, 5 000, 10 000, 15 000, 20 000 mg/kg. In order to better elucidate the biochemical and physiological responses to diesel pollutants, activity of the antioxidant enzymes peroxidase （POD）, catalase （CAT） and ascorbic acid oxidase （AAO） were determined in the plant tissue after 50 d treatment at the levels mentioned above. The results showed that CAT and AAO of stem and leaf exhibited peak enzyme activities on 15 000 mg/kg soil and 10 000 mg/kg soil respectively, and declined at higher concentrations. Additionally, the increment of biomass and the content of soluble protein, as well as chlorophyll content were affected by diesel. The highest restoration effectiveness appeared at the level of 5 000 mg/kg. Collectively, Cyperus rotundus is a potential plant which can be used for restoring the diesel-contaminated soil. 相似文献
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以丹江口水库临近三个省份的5个市的调查数据为依据,建立相关的污染物排放估算模型,采用参数计算、对比分析的研究方法,对污染物中所含化学物质(如氨、氮、COD)及其入河量进行估算.结果发现:入库污染总量中,面源污染占绝对优势;在空间分布上,以南阳盆地和十堰地区贡献占绝对优势,库区区间贡献率较小;在化学元素的形态特征上,对水体的影响主要是以溶解态为主的氮和以颗粒状为主的磷.从面源污染的源头来看,不合理的土地利用造成的土壤侵蚀,薄弱的生态环境所造成的污染物转移,都是造成面源污染步步加深的原因.针对以上对汉中、南阳等5个市之间面源污染总量差异的分析,因地制宜地提出未来丹江口水库农业面源污染治理的科学对策,为丹江口库区的环境保护提供科学依据和借鉴. 相似文献
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采用自助溶剂固态反应法制备出Bi2212及其Ijb和Y掺杂单晶。X射线衍射图表明,除001峰外,没有杂相峰;其晶体结构参数计算表明,随着Pb和Y掺杂量的增加,晶体c-轴常数减小。c-轴方向的电阻-温度曲线则显示其超导转变温度为90K左右。 相似文献
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We established a hydrodynamic model to simulate the pollutant transport and decay process in the case of a pollution incident in the sections of the Yangtze and the Jialing passing through the city area of Chongqing. The Boussinesq assumptions and the Navier-Stokes equations of incompressible fluid were applied to setting up the pollutant diffusion equations and the equations for the decay process. E. coli was taken as the example pollutant, and chloride dosage, light, temperature and ultraviolet intensity were considered in the equations for bacterial decay process. The calculated values of the fluid velocities in the two rivers agree well with corresponding measured results, indicating an ideal accuracy of the model. In simulation, the concentration of E. coli in water was assumed to be zero before the accident. The upriver boundary velocity was ?1.35 m/s for the Jialing flow and 1.75 m/s for the Yangtze flow, and the downriver boundary was water depth set at 0. Simulation results show that the bacteria are transported downstream along the riverbank. A long and narrow pollutant belt develops at 12 h after the start of the accident ascribed to the quick longitudinal transfer. After the pollution sources are cut off, the pollutant concentration decreases slowly, mostly by advection and diffusion, suggesting inadequate self-purification ability of the rivers and the necessity of effective decontaminating measures in the case of a pollution incident. The model can be a useful tool for understanding the polluting situations of an improper discharge incident and evaluating the effects of decontaminating measures for the water body of the Three Gorges Reservoir. 相似文献
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SI Hu BI Hai-pu 《重庆大学学报(英文版)》2008,7(1):1-7
We established a hydrodynamic model to simulate the pollutant transport and decay process in the case of a pollution incident in the sections of the Yangtze and the Jialing passing through the city area of Chongqing. The Boussinesq assumptions and the Navier-Stokes equations of incompressible fluid were applied to setting up the pollutant diffusion equations and the equations for the decay process. E. coli was taken as the example pollutant, and chloride dosage, light, temperature and ultraviolet intensity were considered in the equations for bacterial decay process. The calculated values of the fluid velocities in the two rivers agree well with corresponding measured results, indicating an ideal accuracy of the model. In simulation, the concentration of E. coli in water was assumed to be zero before the accident. The upriver boundary velocity was (1.35 m/s for the Jialing flow and 1.75 m/s for the Yangtze flow, and the downriver boundary was water depth set at 0. Simulation results show that the bacteria are transported downstream along the riverbank. A long and narrow pollutant belt develops at 12 h after the start of the accident ascribed to the quick longitudinal transfer. After the pollution sources are cut off, the pollutant concentration decreases slowly, mostly by advection and diffusion, suggesting inadequate self-purification ability of the rivers and the necessity of effective decontaminating measures in the case of a pollution incident. The model can be a useful tool for understanding the polluting situations of an improper discharge incident and evaluating the effects of decontaminating measures for the water body of the Three Gorges Reservoir. 相似文献
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Investigation of migration of pollutant at the base of Suzhou Qizishan landfill without a liner system 总被引：1，自引：0，他引：1
Hai-jian Xie Yun-min Chen Liang-tong Zhan Ren-peng Chen Xiao-wu Tang Ru-hai Chen Han Ke 《浙江大学学报(A卷英文版)》2009,10(3):439-449
We investigated migration of pollutant at the base of the Suzhou landfill after it had been operated for 13 years. The investigation was carried out by performing chemical analyses on the soil samples taken from the silty clay deposit. Concentrations of chloride, chemical oxygen demand （COD） and the heavy metals in the soil samples were determined using the standard methods. The experimental data showed that the maximum migration depth of chloride was more than 10 m, while the maximum migration depth of COD varied between 1 and 3.5 m. It is believed that the difference is attributed to the variation in diffusion rate and leachate-soil interaction. The chloride profiles also indicated that adveetion may be the dominant contaminant transport mechanism at this site. The total contents ofCu, Pb and Cr are very close to the background levels and the concentration values of these metals mainly are lower than the threshold values specified by the Chinese soil quality standard and the European one. The water-extractable concentrations of COD in the surface of the silty clay generally exceed the limit value specified by the Chinese standard. The concentrations of copper and chromium in pore water are 1-2 orders of magnitude less than the total concentrations of these heavy metals within the soils, implying that heavy metals are mainly adsorbed by the soil particles. Finally, remediation methods were suggested for this landfill site. 相似文献