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51.
梅娟  赵由才 《环境工程学报》2014,8(6):2548-2552
利用甲烷氧化菌菌液增加材料中甲烷氧化菌的数量,可以得到高甲烷氧化率的填埋场甲烷生物氧化覆盖材料。研究发现,渗滤液原水和渗滤液处理尾水均能促进甲烷氧化菌的生长,可利用渗滤液耦合矿化垃圾混合培养制备甲烷氧化菌菌液用于填埋场甲烷减排。填埋龄长的渗滤液原水有着较好的培养效果,得到的菌液在4 d内最高甲烷氧化速率达到2.68 mL/h,超过甲烷氧化菌培养液(nitrate minimal salt medium,NMS)的实验结果。渗滤液中总氮、无机碳、总有机碳和Ni元素的含量对甲烷氧化菌的培养过程影响较大,适用于甲烷氧化培养的渗滤液应满足:总氮1 400 mg/L,总有机碳55 mg/L,Ni元素0.4 mg/L,总磷含量较高。  相似文献   
52.
This paper's survey of the pollution of the Wujin'gang River is important because it is one of the main rivers flowing into Meiliang Bay of Lake Taihu in eastern China. Trace metals (TMs) in this paper are described according to their pollution index (P i). Cluster analysis and correlation analysis are utilized for group sites and to assess co-contamination. Toxicity effect analysis was conducted using individual sediment quality guideline quotients (SQGQs) and mean SQGQs. The results showed that sediment from the Wujin'gang River basin was affected by nutrients, heavy metals, and polycyclic aromatic hydrocarbons (PAHs), which are an essential contamination source for both Meiliang Bay and Zhushan Bay of Lake Taihu. The discharge of TMs has significant correlations to total nitrogen (TN) and total phosphorus (TP); however, no significant correlations were observed between the content of PAHs and TMs. Toxicity effect results show that sediment in the Wujin'gang River basin threatens sediment-dwelling organisms. The harmful effect was mainly caused by heavy metals especially Cd, Cr, Ni, and Cu. Sediment dredging is an effective way to control pollution from internal rivers especially for the pollution of TN and heavy metals in the Wujin'gang River basin.  相似文献   
53.
为解决我国废弃产品环境污染问题和再生资源循环利用的困境,加快生态文明建设和循环经济发展,国务院现已推行生产者责任延伸制度。该项制度的推行实施,可减轻环境治理负担,推动循环经济和清洁生产模式,促进企业技术升级,但该项制度在具体实施过程中尚存在一些问题。以铅蓄电池行业为例,存在的主要问题包括相关制度不健全、回收利用体系不完善、缺乏多部门联动监管机制和有效的经济激励政策等。针对上述问题,结合河南省的废铅蓄电池收集处理制度试点工作,提出铅酸蓄电池行业生产者责任延伸制实施的建议方案,为生产者责任延伸制度更好地推行和实施提供参考。  相似文献   
54.
Trichoderma spp. are among the most widely recognized biocontrol fungi used to inhibit pathogens and promote plant growth. These functions are related to primary and secondary metabolites. This study investigated the different metabolites in Trichoderma asperellum TJ01 cultured for 24 and 72?h using liquid chromatography with triple-quadrupole mass spectrometry. Compared to the 24?h culture of T. asperellum TJ01, the 72?h culture with amino acid metabolism tended to decrease while sugar and lipid metabolisms tended to increase. Furthermore, the 72?h culture had a higher proportion of upregulated flavonoids, in combination with a higher proportion of downregulated alkaloids, and equal proportions of upregulated and downregulated polyphenols and hormones. This study also identified a few valuable medicinal substances such as trigonelline and 5-hydroxytryptophan in T. asperellum TJ01 fermentation cultures.  相似文献   
55.
56.
生态文明制度体系研究——以江苏省为例   总被引:2,自引:1,他引:1       下载免费PDF全文
生态文明制度体系是由制度构成的一个相互配合、有机联系的整体。本文基于文献统计分析与实地调研咨询,从广义和狭义层面,分别对生态文明制度进行梳理。根据国家生态文明建设需求与省级层面实际情况,本文将广义的生态文明制度体系分为源头保护制度体系、损害赔偿与激励体系、追责考评制度体系和污染治理制度体系四大板块,并针对国家与省级重点生态文明制度,构建生态资源保护制度链与污染防治制度链。同时,对制度地位、制度衔接、相互关系及其优化选择进行分析,以提高环境管理效能,推进生态文明研究纵深发展。  相似文献   
57.

Copper ions were first adsorbed by zeolite 4A synthesized from bauxite tailings, the desorption of Cu(II) using Na2EDTA solutions was performed, and the recycling of zeolite 4A in adsorption and desorption was systematically investigated. It was observed that the Cu(II) removal efficiency was directly dependent on the initial pH value. The maximum removal efficiency of Cu(II) was 96.2% with zeolite 4A when the initial pH value was 5.0. Cu(II) was completely absorbed in the first 30 min. It was also observed that the desorption efficiency and zeolite recovery were highly dependent on the initial pH and concentration of Na2EDTA in the solution. The desorption efficiency and percent of zeolite recovered were 73.6 and 85.9%, respectively, when the Na2EDTA solution concentration was 0.05 mol L?1 and the pH value was 8. The recovered zeolites were pure single phase and highly crystalline. After 3 cycles, the removal efficiency of Cu(II) was as high as 78.9%, and the zeolite recovery was 46.9%, indicating that the recovered zeolites have good adsorption capacity and can repeatedly absorb Cu(II).

  相似文献   
58.
Protected areas are a cornerstone for forest protection, but they are not always effective during times of socioeconomic and institutional crises. The Carpathian Mountains in Eastern Europe are an ecologically outstanding region, with widespread seminatural and old‐growth forest. Since 1990, Carpathian countries (Czech Republic, Hungary, Poland, Romania, Slovakia, and Ukraine) have experienced economic hardship and institutional changes, including the breakdown of socialism, European Union accession, and a rapid expansion of protected areas. The question is how protected‐area effectiveness has varied during these times across the Carpathians given these changes. We analyzed a satellite‐based data set of forest disturbance (i.e., forest loss due to harvesting or natural disturbances) from 1985 to 2010 and used matching statistics and a fixed‐effects estimator to quantify the effect of protection on forest disturbance. Protected areas in the Czech Republic, Slovakia, and the Ukraine had significantly less deforestation inside protected areas than outside in some periods; the likelihood of disturbance was reduced by 1–5%. The effectiveness of protection increased over time in these countries, whereas the opposite was true in Romania. Older protected areas were most effective in Romania and Hungary, but newer protected areas were more effective in Czech Republic, and Poland. Strict protection (International Union for Conservation of Nature [IUCN] protection category Ia‐II) was not more effective than landscape‐level protection (IUCN III‐VI). We suggest that the strength of institutions, the differences in forest privatization, forest management, prior distribution of protected areas, and when countries joined the European Union may provide explanations for the strikingly heterogeneous effectiveness patterns among countries. Our results highlight how different the effects of protected areas can be at broad scales, indicating that the effectiveness of protected areas is transitory over time and space and suggesting that generalizations about the effectiveness of protected areas can be misleading.  相似文献   
59.
60.
基于主成分分析法的山东省水资源承载力评价   总被引:3,自引:0,他引:3  
根据水资源承载力评价指标体系研究,从4个方面确定了山东省水资源承载力综合评价指标分级标准.利用2008年<山东省统计年鉴>的数据,运用主成分分析法和统计分析软件SPSS16.0对山东省水资源承载力进行了综合评价,并在主成分得分基础上通过聚类分析将其划分为4种类型.  相似文献   
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