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171.
基于GIS的松花江干流暴雨洪涝灾害风险评估   总被引:12,自引:1,他引:11  
以黑龙江省内的松花江干流流域作为研究区,从现代灾害风险理论出发,综合运用GIS空间分析和灾害风险评估数学方法,对松花江干流流域的暴雨洪涝灾害风险进行了定量评价.研究利用遥感数据和社会经济数据,在空间分析基础上,通过对暴雨洪涝灾害的危险性、承灾体的暴露性、脆弱性以及区域防灾减灾能力的分析,确定影响各个县市暴雨洪涝灾害风险的具体方面.并将因子集成为洪涝灾害风险指数(FDRI),在此基础之上绘制出松花江干流流域的洪涝灾害风险区划图,结果表明松花江干流洪涝灾害风险以哈尔滨和佳木斯两市最大,上游洪涝灾害风险大于下游.  相似文献   
172.
Na He  Peijun Li  Yuncheng Zhou  Shuxiu Fan  Wanxia Ren   《Chemosphere》2009,76(11):1491-1497
The reductive dechlorination and biodegradation of 2,24,5,5-pentachlorobiphenyl (PCB#101) was investigated in a laboratory-scale. Palladium coated iron (Pd/Fe) was used as a catalytic reductant for the chemical degradation of 2,24,5,5-pentachlorobiphenyl, and an aerobic bacteria was used for biodegradation following the chemical reaction in this study. Dechlorination was affected by several factors such as Pd loading, initial soil pH and the amount of Pd/Fe used. The results showed that higher Pd loading, higher dosage of Pd/Fe and slightly acid condition were beneficial to the catalytic dechlorination of 2,2,4,5,5-pentachlorobiphenyl. In laboratory batch experiments, 2,24,5,5-pentachlorobiphenyl was reduced in the presence of Pd/Fe bimetal, which was not further degraded by aerobic bacteria. 2,2,4-trichlorobiphenyl (PCB#17), a reduction product from 2,24,5,5-pentachlorobiphenyl, was readily biodegraded in the presence of a aerobic bacterial strain. It is suggested that an integrated Pd/Fe catalytic reduction-aerobic biodegradation process may be a feasible option for treating PCB-contaminated soil.  相似文献   
173.
传统的评价方法费时费力,效率低下.将计算机技术与评价方法相结合是评价工作发展的趋势.介绍了为世界各国石油化工企业所广为接受的美国道化学公司(DOW)火灾、爆炸危险性指数评价法,以及根据该法的评价思路所开发的辅助软件的设计思路和功能.  相似文献   
174.
为研究紫外吸收剂2-羟基-4-甲氧基二苯甲酮-5-磺酸(BP-4)的最大生物降解能力,采用欧洲经济合作与发展组织(OECD)生物降解测试标准方法——303A模拟试验-污水好氧处理:活性污泥单元法,建立并进行了城市污水处理厂曝气池环境模拟试验。研究结果表明:在单一新鲜活性污泥作为接种物条件下,BP-4在第47天达到降解稳定期,溶解性有机碳(DOC)去除率平均值为36.90%±5.68%(n=18)。在以10种不同来源混合接种物条件下,BP-4在第41天达到降解稳定期,去除率平均值为33.11%±4.87%(n=17)。研究结果表明BP-4在环境中的降解能力有限,在本模拟方法试验条件下只能部分降解。  相似文献   
175.
禾草灵是一种广泛使用的除草剂,在土壤中大量残留,对非靶标生物产生危害。为探究除草剂对环境生物的毒性作用,本研究模拟水稻自然生长的环境,评估禾草灵对水稻及土壤微生物的影响。研究结果表明,低浓度禾草灵(200 μg L-1)处理4 d对土壤微生物量没有显著影响(P>0.05);8 d时,水稻生长没有明显变化,但土壤微生物量较对照组显著升高(P<0.05)。高浓度禾草灵(1 000 μg L-1)处理4天后,土壤脲酶、酸性磷酸酶和过氧化氢酶的活性显著下降(P<0.05),下降幅度分别为8.9%,16.6%和10.2%;处理8 d后,水稻幼苗鲜重显著降低(P>0.05),叶绿素a和叶绿素b含量分别下降了13.5%和13.3%。本研究证实高浓度的禾草灵残留会对植物和土壤微生物产生不良的影响。  相似文献   
176.
The noncooperative air pollution reduction model (NCRM) that is currently adopted in China to manage air pollution reduction of each individual province has inherent drawbacks. In this paper, we propose a cooperative air pollution reduction game model (CRM) that consists of two parts: (1) an optimization model that calculates the optimal pollution reduction quantity for each participating province to meet the joint pollution reduction goal; and (2) a model that distribute the economic benefit of the cooperation (i.e., pollution reduction cost saving) among the provinces in the cooperation based on the Shapley value method. We applied the CRM to the case of SO2 reduction in the Beijing–Tianjin–Hebei region in China. The results, based on the data from 2003–2009, show that cooperation helps lower the overall SO2 pollution reduction cost from 4.58% to 11.29%. Distributed across the participating provinces, such a cost saving from interprovincial cooperation brings significant benefits to each local government and stimulates them for further cooperation in pollution reduction. Finally, sensitivity analysis is performed using the year 2009 data to test the parameters’ effects on the pollution reduction cost savings.

Implications: China is increasingly facing unprecedented pressure for immediate air pollution control. The current air pollution reduction policy does not allow cooperation and is less efficient. In this paper we developed a cooperative air pollution reduction game model that consists of two parts: (1) an optimization model that calculates the optimal pollution reduction quantity for each participating province to meet the joint pollution reduction goal; and (2) a model that distributes the cooperation gains (i.e., cost reduction) among the provinces in the cooperation based on the Shapley value method. The empirical case shows that such a model can help improve efficiency in air pollution reduction. The result of the model can serve as a reference for Chinese government pollution reduction policy design.  相似文献   
177.
不同流量分配比对多级A/O工艺去除有机物及脱氮的影响   总被引:1,自引:0,他引:1  
采用三级A/O工艺分段进水工艺处理低碳源生活污水,考察了进水流量分配比对系统去除有机物、硝化反硝化能力以及去除TN的影响。通过对水质指标沿程监测结果表明,不同流量分配比(4∶3∶3,5∶3∶2,6∶3∶1)对系统去除有机物及硝化效率影响不大,出水COD、氨氮分别均在30 mg/L、1 mg/L以下。但反硝化效果受流量分配比的影响较大,在流量比为5∶3∶2时,有效利用原水中碳源进行反硝化,反硝化效果最好。在流量比为5∶3∶2的情况下,TN出水为5.7 mg/L去除率为82.9%,优于流量分配比为6∶3∶1和4∶3∶3时的脱氮效果。总体而言,分段进水工艺在对碳源的有效利用及能耗节省方面优于单点进水。  相似文献   
178.
微生物法适用于海上钻井含油废弃物的处理。通过多次对菌株采集、分离、纯化和培养驯化,选育得到了3株对石油烃类有很好降解效果的石油类降解菌;确定了石油类降解菌适宜的生化处理条件:最佳生长及原油降解温度为50℃、最佳生长及原油降解酸碱性环境为pH=6.0、最佳菌株接种量2%、最佳原油初始浓度为500mg/L。处理后的含油废弃钻井液含油量基本稳定在2mg/L以下,降解率达98%以上。  相似文献   
179.
Yu DJ  Lai BS  Li J  Ma YF  Yang F  Li Z  Luo XQ  Chen X  Huang YF 《Chemosphere》2012,86(1):70-75
Triclosan is used as an antibacterial agent in household items and personal care products. Since this compound is found in maternal milk of humans and bodies of wild animals, there is growing concern among some consumer groups and scientific community that triclosan is adverse for humans and wild animals. In order to estimate adverse actions of triclosan, the effects of triclosan on intracellular Zn2+ concentration and cellular thiol content were studied in rat thymocytes by the use of flow cytometer with appropriate fluorescent probes. Triclosan at 1-3 μM (sublethal concentrations) increased the intensity of FluoZin-3 fluorescence (intracellular Zn2+ concentration) and decreased the intensity of 5-chloromethylfluorescein (5-CMF) fluorescence (cellular thiol content). Negative correlation (r = −0.985) between triclosan-induced changes in FluoZin-3 and 5-CMF fluorescences was found. Removal of external Zn2+ did not significantly affect the triclosan-induced augmentation of FluoZin-3 fluorescence, suggesting an intracellular Zn2+ release by triclosan. These actions of triclosan were similar to those of H2O2 and triclosan significantly potentiated the cytotoxicity of H2O2. Therefore, the results may suggest that triclosan at sublethal concentrations induces oxidative stress that decreases cellular thiol content, resulting in an increase in intracellular Zn2+ concentration by Zn2+ release from intracellular store(s). Since recent studies show many physiological roles of intracellular Zn2+ in cellular functions, the triclosan-induced disturbance of cellular Zn2+ homeostasis may induce adverse actions on the cells.  相似文献   
180.
Fan W  Jia Y  Li X  Jiang W  Lu L 《Chemosphere》2012,88(6):751-756
A microorganism was isolated from oil field injection water and identified as Rhodobacter sphaeroides. It was used for the remediation of simulated cadmium-contaminated soil. The phytoavailability of Cd was investigated through wheat seedling method to determine the efficiency of remediation. It was found that after remediation, the accumulation of Cd in wheat roots and leaves decreased by 67% and 53%, respectively. The Cd speciation in soil was determined with Tessier extraction procedure. It was found that the total Cd content in soil did not change during the experiments, but the geo-speciation of Cd changed remarkably. Among the five fractions, the concentration of exchangeable phases decreased by 27-46% and that of the phases bound to Fe-Mn oxides increased by 22-44%. The decrease of Cd accumulation in wheat showed significant positive correlation with the decrease of exchangeable phases. It could be concluded that the remediation of R. sphaeroides was carried out through the conversion of Cd to more stable forms. The decrease of sulfate concentration in supernatant indicated that the R. sphaeroides consumed sulfate.  相似文献   
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