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31.
Li Chen Mengshuang Shi Suhuan Li Shuang Gao Hui Zhang Yanling Sun Jian Mao Zhipeng Bai Zhongliang Wang Jiang Zhou 《环境科学学报(英文版)》2017,29(7):33-40
In 2013,China issued "Air Pollution Prevention and Control Action Plan(Action Plan)" to improve air quality.To assess the benefits of this program in Beijing-Tianjin-Hebei(BTH)region,where the density of population and emissions vary greatly,we simulated the air quality benefit based on Ben MAP to satisfy the Action Plan.In this study,we estimate PM_(2.5) concentration using Voronoi spatial interpolation method on a grid with a spatial resolution of 1 × 1 km~2.Combined with the exposure-response function between PM_(2.5) concentration and health endpoints,health effects of PM_(2.5) exposure are analyzed.The economic loss is assessed by using the willingness to pay(WTP) method and human capital(HC) method.When the PM_(2.5) concentration falls by 25% in BTH and reached 60 μg/m~3 in Beijing,the avoiding deaths will be in the range of 3175 to 14051 based on different functions each year.Of the estimated mortality attributable to all causes,3117 annual deaths were due to lung cancer,1924 – 6318 annual deaths were due to cardiovascular,and343 – 1697 annual deaths were due to respiratory.Based on WTP,the estimated monetary values for the avoided cases of all cause mortality,cardiovascular mortality,respiratory mortality and lung cancer ranged from 1110 to 29632,673 to 13325,120 to 3579,1091 to 6574 million yuan,respectively.Based on HC,the corresponding values for the avoided cases of these four mortalities were 267 to 1178,161 to 529,29 to 143 and 261 million yuan,respectively. 相似文献
32.
The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers'' information and vehicles'' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model. 相似文献
33.
为了探讨AM(arbuscular mycorrhizal,丛枝菌根)真菌在Sb(锑)胁迫下对农作物生长及吸收Sb的影响,采用盆栽试验研究了在不同Sb添加量[即w(Sb)分别为0、500、1 000 mg/kg]下,接种AM真菌对玉米植株生物量以及N、P和Sb的吸收、膜脂过氧化[MDA(丙二醛)]和抗氧化酶活性的影响.结果表明:随着土壤中Sb添加量的增加,玉米植株的生物量、w(TN)和w(TP)均呈显著下降趋势,植株体内的w(Sb)和Sb积累量、MDA含量、CAT(过氧化氢酶)以及POD(过氧化酶)活性均显著上升.与未接种组相比,接种AM真菌显著促进了玉米植株的生长,提高了玉米植株地上部分的w(TN)和w(TP).在3个Sb添加量处理下,接种显著增加了玉米植株地下部分的w(Sb)、地上和地下部分的Sb积累量以及地上部分的CAT活性,增幅分别为8.90%~23.30%、18.87%~28.37%、27.68%~78.95%及14.92%~88.52%;同时,接种降低了玉米植株中Sb的转运率、玉米植株地上部分的w(Sb)和MDA含量,在1000 mg/kg Sb添加量下差异达显著水平,三者分别降低了36.35%、22.81%和24.29%.研究显示,在Sb污染环境下,接种AM真菌能够减轻玉米植株膜脂过氧化程度,在提高玉米植株地下部分w(Sb)的同时,也会降低Sb向地上部分的转运,减轻Sb对玉米的毒害作用. 相似文献
34.
应用时间破裂分析方程中表征地震距释放程度的m值,选取不同空间尺度进行时空扫描研究,得到震前1年以每2个月为时间间隔的空间m值随时间变化的分布图像,运用不同参数设置计算了地震前Benioff累积应变释放特征。通过对比这些变化找出研究区内m值空间分布搜索主震破裂点扫描效果较好的参数模型,尝试性地给出了"矩释放程度空间扫描"方法应用于地震预测的经验指标。并结合与矩加速释放具有相同物理机制的加卸载响应比(Load/Unload Response Ratio)方法进行综合分析,利用这两种方法对地震进行中短期预测,达到两种方法互相检验、相互辅助的目的。考虑到本文仅对6个震例进行研究,无法给出具有统计显著性的结论,所以仍需结合其他方法进行点、线、面的综合分析。 相似文献
35.
A pilot-scale study of cryolite precipitation from high fluoride-containing wastewater in a reaction-separation integrated reactor 总被引:2,自引:0,他引:2
Fluoride removal by traditional precipitation generates huge amounts of a water-rich sludge with low quality, which has no commercial or industrial value. The present study evaluated the feasibility of recovering fluoride as low water content cryolite from industrial fluoride-containing wastewater. A novel pilot-scale reaction-separation integrated reactor was designed. The results showed that the seed retention time in the reactor was prolonged to strengthen the induced crystallization process. The particle size of cryolite increased with increasing seed retention time, which decreased the water content. The recovery rate of cryolite was above 75% under an influent fluoride concentration of 3500 mg/L, a reaction temperature of 50℃, and an influent flow of 40 L/hr. The cryolite products that precipitated from the reactor were small in volume, large in particle size, low in water content, high in crystal purity, and recyclable. 相似文献
36.
37.
采用溶胶-凝胶法制备酞菁-TiO2光催化剂,并分别掺杂铁、铜、钴、镍元素。酞菁作为光敏化剂,提高TiO2在可见光下对有机染料的降解效果。采用SEM对催化剂进行表征,研究在可见光下酞菁-TiO2光催化剂对5种有机染料(甲基橙、甲基红、甲酚紫、亚甲基蓝和孔雀石绿)的降解效果,结果表明,酞菁铁-TiO2,酞菁钴-TiO2,酞菁铜-TiO2,酞菁镍-TiO2均能有效降解这几种有机染料,光催化反应300 min后降解率达92%。比较4种催化剂对甲基橙的降解率,酞菁钴-TiO2催化剂降解效果最明显,以下是酞菁铁、酞菁镍和酞菁铜-TiO2催化剂。 相似文献
38.
论述了输油泵站控制系统及微波通信系统遭受雷击的危害及原因,有针对性地采取了各种防雷的有效措施,完善微波通讯和站控及网络防雷保护系统,为确保输油安全生产提供了有利保证. 相似文献
39.
在硫酸系统中,通过水平衡分析计算烟气带入净化工序的SO2体积分数和含水量,确定净化工序的能力,控制干燥塔进口烟气温度,使干吸工序生产出合格产品;通过计算,烟气带入净化工序的水量小于产品带出的水量,制酸净化污水经过污水处理工序处理后返回到净化工序重复使用,实现净化污水零排放,消除对环境的污染. 相似文献
40.
Yanhui Li Bing Xi Quansheng Zhao Fuqiang Liu Pan Zhang Qiuju Du Dechang Wang Da Li Zonghua Wang Yanzhi Xia 《环境科学学报(英文版)》2011,23(3):404-411
Kaolin has been widely used as an adsorbent to remove heavy metal ions from aqueous solutions. However, the lower heavy metal
adsorption capacity of kaolin limits its practical application. A novel environmental friendly material, calcium alginate immobilized
kaolin (kaolin/CA), was prepared using a sol-gel method. The e ects of contact time, pH, adsorbent dose, and temperature on Cu2+
adsorption by kaolin/CA were investigated. The Langmuir isotherm was used to describe the experimental adsorption, the maximum
Cu2+ adsorption capacity of the kaolin/CA reached up to 53.63 mg/g. The thermodynamic studies showed that the adsorption reaction
was a spontaneous and endothermic process. 相似文献