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441.
采用含固定化微生物的曝气生物滤池(G-BAF)处理炼油厂高浓度废水。当G-BAF池进水COD为298~11 278 mg/L时,出水COD为33.0~94.3 mg/L,COD平均去除率为97%;当G-BAF池进水ρ(NH_3-N)为12.1~188.0 mg/L时,出水ρ(NH_3-N)为0.9~49.4 mg/L,NH_3-N平均去除率为83%。经G-BAF处理后出水水质完全达到GB8978—1996《污水综合排放标准》第二类污染物的二级排放标准。  相似文献   
442.
Biodiversity maintenance and soil improvement are key sustainable forestry objectives. Research on the effects of bamboo forest management on plant diversity and soil properties are therefore necessary in bamboo-growing regions, such as southeastern China’s Shunchang County, that have not been studied from this perspective. We analyzed the effects of different Phyllostachys pubescens proportions in managed forests on vegetation structure and soil properties using pure Cunninghamia lanceolata forests as a contrast, and analyzed the relation between understory plants and environmental variables (i.e., topography, stand and soil characteristics) by canonical correspondence analysis (CCA). The forest with 80% P. pubescens and 20% hardwoods (such as Phoebe bournei, Jatropha curcas, Schima superba) maintained the highest plant diversity and best soil properties, with significantly higher plant diversity than the C. lanceolata forest, and better soil physicochemical and biological properties. The distribution of understory plants is highly related to environmental factors. Silvicultural disturbance strongly influenced the ability of different bamboo forests to maintain biodiversity and soil quality under extensive management, and the forest responses to management were consistent with the intermediate-disturbance hypothesis (i.e., diversity and soil properties were best at intermediate disturbance levels). Our results suggest that biodiversity maintenance and soil improvement are important management goals for sustainable bamboo management. To achieve those objectives, managers should balance the inputs and outputs of nutrients and protect understory plants by using appropriate fertilizer (e.g., organic fertilizer), adjusting stand structure, modifying utilization model and the harvest time, and controlling the intensity of culms and shoots harvests.  相似文献   
443.
矿山尾矿酸性废水源头控制技术研究进展   总被引:1,自引:0,他引:1  
胡鸿  王峰  杨海真 《四川环境》2010,29(3):98-101,109
矿山尾矿酸性废水的治理是采矿行业关注的一个热点问题。作者在论述矿山尾矿酸性废水的成因、水质特征及危害的基础上,评述了主要的源头控制技术方法,包括尾矿脱硫技术、施用T.f菌杀菌剂技术、覆盖法、表面钝化处理技术,指出了各种源头控制技术方法在实际应用中面临的一些问题,提出源头控制技术和末端治理技术的联合使用将会是未来研究的重点。  相似文献   
444.
低SO_2氧化率脱硝催化剂的开发   总被引:1,自引:0,他引:1  
介绍了SCR脱硝催化剂中V2O5对SO2的氧化及SO2氧化对脱硝催化剂及其下游设备的危害,分析了脱硝催化剂中V2O5对SO2氧化的原理和影响因素,探讨了低SO2氧化率脱硝催化剂开发方面的研究成果。  相似文献   
445.
清洁发展机制在石油行业的潜力分析   总被引:1,自引:1,他引:0  
系统分析了石油行业清洁发展机制项目的潜力,并提出了建议。在统计与石油行业相关的清洁发展机制方法学及其注册项目和温室气体减排量的基础上,给出了各方法学与石油行业的相关性。从勘探与生产、天然气与管道、炼油与化工三大领域,分析了石油行业潜在的清洁发展机制项目领域。最后,提出了对石油行业开展清洁发展机制相关工作的建议。  相似文献   
446.
区域间产业结构的同构与异构取决于在市场调节和宏观调控中生产要素的结构与流动特征,其特征量的相似性导致产业结构的同构,产业同构在一定时空条件下具有合意性。随着区域经济一体化进程的加快,其非合意性愈显突出。区域产业同构优化的本质动力在于生产要素结构及其流动特征量的变化,通过不同层级区域产业规划战略和区域间经济合作实现生产要素的合理组合与流动,以产业集群化之路实现区域产业结构的高级化,使区域产业结构朝着优化、持续方向发展。  相似文献   
447.

Background, aim, and scope  

Polybrominated diphenyl ethers (PBDEs) and their metabolites are toxic to animals, and concentrations of the PBDEs metabolites can exceed those of the parent materials. But no information was available on concentrations of PBDEs metabolites in the lower Yangtze River in the region around Jiangsu Province of China, which is heavily urbanized and industrialized area. The aims of this study were to determine whether PBDEs and their methoxylated PBDEs (MeO-PBDEs) were accumulated in Coilia sp. in this area and to investigate the potential sources for these two kinds of brominated organic pollutants.  相似文献   
448.

Background, aim, and scope  

Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves.  相似文献   
449.
Atmospheric deposition of phthalate esters in a subtropical city   总被引:1,自引:0,他引:1  
In Chinese cities, air pollution has become a serious and aggravating environmental problem undermining the sustainability of urban ecosystems and the quality of urban life. Bulk atmospheric deposition samples were collected two-weekly, from February 2007 to January 2008, at three representative areas, one suburban and two urbanized, in the subtropical city, Guangzhou, China, to assess the deposition fluxes and seasonal variations of phthalate esters (PAEs). Sixteen PAE congeners in bulk deposition samples were measured and the depositional fluxes of ∑16PAEs ranged from 3.41 to 190 μg m?2 day?1, and were highly affected by local anthropogenic activities. The significant relationship between PAEs and particulate depositional fluxes (correlation coefficient R2 = 0.72, P < 0.001) showed PAEs are associated primarily with particles. Temporal flux variations of PAEs were influenced by seasonal changes in meteorological parameters, and the deposition fluxes of PAEs were obviously higher in wet season than in dry season. Diisobutyl phthalate (DiBP), Di-n-butyl phthalate (DnBP), and Di(2-ethylhexyl) phthalate (DEHP) dominated the PAE pattern in bulk depositions, which is consistent with a high consumption of the plasticizer market in China. PAE profiles in bulk deposition showed similarities exhibited in both time and space, and a weak increase of high molecular weight PAE (HMW PAE) contribution in the wet season compared to those in the dry season. Average atmospheric deposition fluxes of PAEs in the present study were significantly higher than those from other studies, reflecting strong anthropogenic inputs as a consequence of rapid industrial and urban development in the region.  相似文献   
450.
树脂固载纳米铁对偶氮染料直接湖蓝5B的脱色性能研究   总被引:4,自引:1,他引:3  
以FeSO4和NaBH4水溶液为前驱溶剂,以聚苯乙烯型阳离子交换树脂为载体,制备了树脂固载的纳米铁,室温下用于对偶氮染料直接湖蓝5B水溶液进行脱色研究。研究结果发现,脱色反应遵循准一级反应动力学,在初始pH为3~10的范围内,反应进行14 m in时,50 mg/L的染料溶液脱色率均能达到83%以上。固载的纳米铁材料可多次重复利用,溶液中释放的铁离子浓度不超过0.1 mg/L。  相似文献   
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