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971.
Identification of optimal strategies for improving eco-resilience to floods in ecologically vulnerable regions of a wetland 总被引:4,自引:0,他引:4
In this study, a mixed integer fuzzy interval-stochastic programming model was developed for supporting the improvement of eco-resilience to floods in wetlands. This method allows uncertainties that are associated with eco-resilience improvement and can be presented as both probability distributions and interval values to be incorporated within a general modeling framework. Also, capacity-expansion plans of eco-resilience can be addressed through introducing binary variables. Moreover, penalties due to ecological damages which are associated with the violation of predefined targets can be effectively incorporated within the modeling and decision process. Thus, complexities associated with flood resistance and eco-resilience planning in wetlands can be systematically reflected, highly enhancing robustness of the modeling process. The developed method was then applied to a case of eco-resilience enhancement planning in three ecologically vulnerable regions of a wetland. Interval solutions under different river flow levels and different ecological damages were generated. They could be used for generating decision alternatives and thus help decision makers identify desired eco-resilience schemes to resist floods without causing too much damages. The application indicates that the model is helpful for supporting: (a) adjustment or justification of allocation patterns of ecological flood-resisting capacities, (b) formulation of local policies regarding eco-resilience enhancement options and policy interventions, and (c) analysis of interactions among multiple administrative targets within a wetland. 相似文献
973.
974.
文章利用三维荧光光谱技术和平行因子分析技术,识别并分析了西北地区皮里青河流域林地、耕地、草地及裸地4种典型利用类型土壤DOM特性,以期明晰该流域典型土地利用类型土壤DOM地化特征.结果 表明,4种土地利用类型均存在紫外类腐殖质荧光峰A、可见类富里酸荧光峰C、陆源腐殖质峰M,但强度有所不同.A、C、M峰荧光强度大小顺序均为林地>草地>耕地>裸地.所有样品DOM均由内外源共同产生,但是林地和裸地陆源特征更明显,林地腐殖化程度较高,并且存在更多的芳香性和疏水组分.研究发现,DOC和CDOM之间未出现相关性(P>0.5),FDOM和DOC之间存在低度正相关性(P<0.05,r2=0.22),FDOM和CDOM之间存在中等正相关性(P<0.05,r2=0.52).5个荧光光谱特征参数获取到了2个主成分,PC1和PC2分别反映了DOM结构特性、来源特性.平行因子分析发现,4种土地利用类型土壤DOM均存在C1组分,与EEMs图结果相比,林地产生较明显红移现象. 相似文献
975.
Meng Si Boxiong Shen George Adwek Lifu Xiong Lijun Liu Peng Yuan Hongpei Gao Cai Liang Qihai Guo 《环境科学学报(英文版)》2021,33(3):49-71
Due to the increasingly strict emission standards of NOx on various industries, many traditional flue gas treatment methods have been gradually improved. Except for selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) methods to remove NOx from flue gas, theoxidation method is paying more attention to NOx removal now because of the potential to simultaneously remove multiple pollutants from flue gas. This paper summarizes the efficiency, reaction conditions, effect factors, and reaction mechanism of NO oxidation from the aspects of liquid-phase oxidation, gas-phase oxidation, plasma technology, and catalytic oxidation. The effects of free radicals and active components of catalysts on NO oxidation and the combination of various oxidation methods are discussed in detail. The advantages and disadvantages of different oxidation methods are summarized, and the suggestions for future research on NO oxidation are put forward at the end. The review on the NO removal by oxidation methods can provide new ideas for future studies on the NO removal from flue gas. 相似文献
976.
利用粉煤灰合成沸石处理重金属污水研究 总被引:10,自引:0,他引:10
本研究中利用粉煤灰合成沸石对含有Cu^2 、Pb^2 、Cd^2 的制备水样进行批处理振荡实验,其吸附容量分别为9.56、0.89和0.25mg/l。实验证明,用合成沸石处理含重金属离子污水达到平衡所需的时间约为3h。对污水中重金属离子的去除率随pH值降低而降低,随沸石用量增加而增加。同等条件下,利用粉煤灰处理含Cu^2 的污水,其吸附容量仅为6.49mg/l,低于合成沸石。 相似文献
977.
978.
Ying Wang Ailing Zhu Yingying Fang Changjun Fan Yanli Guo Zhiqiang Tan Yongguang Yin Yong Cai Guibin Jiang 《环境科学学报(英文版)》2022,34(5):403-410
A simple and efficient dithizone-functionalized solid-phase extraction (SPE) procedure, online coupled with high-performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry, was developed for the first time for enrichment and determination of ultra-trace mercury (Hg) species (inorganic divalent Hg (Hg(II)), methylmercury (CH3Hg(II)) and ethylmercury (C2H5Hg(II)) in cereals and environmental samples. In the proposed method, functionalization of the commercial C18 column with dithizone, enrichment, and elution of the above Hg species can be completed online with the developed SPE device. A simple solution of 2-mercaptoethanol (1% (V/V)) could be used as an eluent for both the SPE and HPLC separation of Hg species, significantly simplifying the method and instrumentation. The online SPE method was optimized by varying dithizone dose, 2-mercaptoethanol concentration, and sample volume. In addition, the effect of pH, coexisting interfering ions, and salt effect on the enrichment was also discussed. Under the optimized conditions, the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(II), 0.07 ng/L for CH3Hg(II), and 0.04 ng/L for C2H5Hg(II) with recoveries in the range of 85%–100%. The developed dithizone-functionalized C18 SPE column can be reused after a single functionalization, which significantly simplifies the enrichment step. Moreover, the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis. This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples. 相似文献
979.
通过分析国内外研究,阐述了常规洗井和取样(以潜水泵洗井,提桶或贝勒管取样为例)过程的一些弊端,并介绍了一种国内文献中未见的方法—低流速法。该法所采得的样品在代表性方面优势更加明显,获得的数据更加准确。 相似文献
980.