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361.
基于OREMS的城市应急交通疏散研究   总被引:1,自引:1,他引:0  
以天津奥林匹克中心地区在突发事件下的疏散为例来研究城市中的应急交通疏散。由GIS提供天津奥林匹克中心地区的道路和人口数据,利用美国国家橡树岭实验室为美国联邦公路局开发的应急交通疏散仿真软件OREMS(Oak Ridge Evacuation Modeling System)对该地区的路网进行建模,并对人为交通控制策略下的疏散进行仿真模拟,得出疏散过程中疏散车辆数随时间的变化、瓶颈节点和路段以及完成疏散所需的时间等疏散效能参数,从而为制定应急策略提供相应的参考。  相似文献   
362.
浙江近岸海域有害赤潮发生区麻痹性贝毒素研究   总被引:4,自引:0,他引:4  
用小白鼠生物检测法和高效液相色谱法对采自浙江舟山海域和浙江中南部海域的麻痹性贝毒素进行了调查分析。结果表明,浙江舟山海域六横岛的西格织纹螺含有贝毒,其毒素为3,7Mu/g,舟山海域有毒贝类检出率为3.1%;浙江中南部海域南麂列岛的棒锥螺含有贝毒,其毒素〈1.7Mu/g,浙江中、南部海域有毒贝类检出率为9.1%。  相似文献   
363.
Sun  Hui  Zhang  Hengyuan  Mao  Huimin  Yu  Bin  Han  Jian  Bhat  Gajanan 《Environmental Chemistry Letters》2019,17(2):1091-1096
Environmental Chemistry Letters - Dyeing wastewaters present high hazards for the environment and human health. Advanced dye removal may be achieved by magnetic metal–organic frameworks...  相似文献   
364.
Mao  Lei  Pan  Lijian  Ma  Bomou  He  Yong 《Journal of Polymers and the Environment》2022,30(3):1072-1079
Journal of Polymers and the Environment - In this research, bio-based polyamide (bio-PA) was synthesized from dimethyl furan-2,5-dicarboxylate and 1,3-cyclohexanedimethanamine by melt...  相似文献   
365.
Environmental Science and Pollution Research - Spatio-temporal evolution of post-seismic landslides and debris flows provides a new perspective to understand post-earthquake evolution of geological...  相似文献   
366.
Environmental Science and Pollution Research - An increasing number of studies investigated the association between air pollution during pregnancy and the risk of eczema in offspring. However, no...  相似文献   
367.
基于博弈论的地铁车站恐怖袭击风险定量研究   总被引:3,自引:0,他引:3  
近年来发生的几起地铁重大恐怖袭击事件引起了各国政府、媒体和公众的广泛关注.地铁车站恐怖袭击可以看作博弈双方即袭击者和防御者之间的零和博弈.本文以某地铁线路上的22个车站为例,应用目标损失概率模型定量分析了恐怖袭击风险,通过防御资源变化得到了不同的目标损失概率.研究结果可以为地铁车站防御资源优化配置、防恐反恐预案编制等提供量化依据.  相似文献   
368.
茅坪河流域非点源污染负荷模拟   总被引:13,自引:1,他引:12  
许其功  刘鸿亮  沈珍瑶  冒亚明 《环境科学》2006,27(11):2176-2181
为定量化研究茅坪河流域农业非点源营养物质氮、磷的输出负荷,在茅坪河的亚流域陈家冲,利用2004-05~2004-10降雨期的监测数据,通过实测值和模拟值的比较对非点源污染模型SWAT(Soil and Water Assessment Tool)进行了率定和验证,采用Nash-Sutcliffe系数(R2)、均方根差(RMSE)和相对误差(CV)检验实测值和模拟值的拟合度.利用验证后的模型模拟了茅坪河流域营养物质氮、磷的输出负荷量.经验证径流、总氮和总磷的Nash-Sutcliffe系数分别为0.71、0.51和0.62,最小相对误差分别为1.8%、1.1%和10%,模型对氮和磷的输出模拟效果稍差,但对径流的模拟取得了较好的效果,表明该模型可运用于茅坪河流域非点源污染的模拟研究.模拟结果显示,2004-05~2004-10,茅坪河流域共有102.5 t氮和9.46 t磷流入长江,大量农业非点源污染的产生是造成茅坪河水质恶化的重要原因之一.  相似文献   
369.
A study was conducted to determine the adsorption/desorption of butachlor, myclobutanil and chlorpyrifos on five soils using a batch equilibration technique and to study the relationship between bioavailability to Allolobophora caliginosa and the adsorption/desorption of these three pesticides. The results showed that the adsorption/desorption processes of the tested compounds were mainly controlled by soil organic matter content (OM) and octanol/water-partitioning coefficient (K(ow)), and that the bioavailability of the pesticides was dependent on characteristics of pesticides, properties of soils, and uptake routes of earthworms. Bioconcentration of butachlor and myclobutanil was negatively correlated with Freundlich adsorption constant K(af) and K(df). However, only a slightly positive correlation between bioconcentration and K(af) and K(df) was observed for chlorpyrifos due to its high affinity onto soil.  相似文献   
370.
Liu Y  Qin X  Guo H  Zhou F  Wang J  Lv X  Mao G 《Environmental management》2007,40(6):966-980
Lake areas in urban fringes are under increasing urbanization pressure. Consequently, the conflict between rapid urban development and the maintenance of water bodies in such areas urgently needs to be addressed. An inexact chance-constrained linear programming (ICCLP) model for optimal land-use management of lake areas in urban fringes was developed. The ICCLP model was based on land-use suitability assessment and land evaluation. The maximum net economic benefit (NEB) was selected as the objective of land-use allocation. The total environmental capacity (TEC) of water systems and the public financial investment (PFI) at different probability levels were considered key constraints. Other constraints included in the model were land-use suitability, governmental requirements on the ratios of various land-use types, and technical constraints. A case study implementing the system was performed for the lake area of Hanyang at the urban fringe of Wuhan, central China, based on our previous study on land-use suitability assessment. The Hanyang lake area is under significant urbanization pressure. A 15-year optimal model for land-use allocation is proposed during 2006 to 2020 to better protect the water system and to gain the maximum benefits of development. Sixteen constraints were set for the optimal model. The model results indicated that NEB was between $1.48 × 109 and $8.76 × 109 or between $3.98 × 109 and $16.7 × 109, depending on the different urban-expansion patterns and land demands. The changes in total developed area and the land-use structure were analyzed under different probabilities (q i ) of TEC. Changes in q i resulted in different urban expansion patterns and demands on land, which were the direct result of the constraints imposed by TEC and PFI. The ICCLP model might help local authorities better understand and address complex land-use systems and develop optimal land-use management strategies that better balance urban expansion and grassland conservation.  相似文献   
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