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931.
我国环保基础设施建设融资的ABS方式 总被引:1,自引:0,他引:1
本文阐述了我国环保基础设施建设资金短缺的情况,指出必须利用金融创新为环保融资服务,ABS融资就是其中的一种方法。本文介绍了ABS融资方式的涵义,并提出了其在环保基础设施融资方面所具有的优势,即保障国家安全、降低融资风险、降低融资成本、筹资前景广阔和改善公司财务状况,同时,也指出了使用ABS方式进行融资的所应当注意的一些问题,即保障可预期的现金流问题以及风险管理问题,并针对这些问题提出了相应的解决对 相似文献
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Tao X Tang C Wu P Han Z Zhang C Zhang Y 《Journal of environmental monitoring : JEM》2011,13(11):3269-3276
Occurrence, variation and behaviour of nonylphenol (NP) and octylphenol (OP) were studied in surface water and groundwater in Guiyang, Guizhou Province, southwestern China. Discharge of wastewater from Guiyang City was the main source of alkylphenols (APs) entering the aquatic environment. The concentrations of NP and OP in river water ranged from 40 to 1582 ng L(-1) and from below the lowest limit of detection (LOD) to 67 ng L(-1), respectively. NP and OP were also detected in groundwater. Both NP and OP exhibited spatial and temporal variations in river water and groundwater. It was found that concentrations of NP and OP in river water was low upstream and dramatically increased downstream, and higher concentration of NP was found in winter compared to that in summer. Proportions of NP and OP were trapped by suspended particulate matter (SPM), which accounted for 7.6-50.0% and 3.4-25.6% of their total concentration in the river water system, respectively. Seasonal changes in water flow were responsible for the temporal variations of APs. To determine the behaviour of APs along the river, a mass balance equation based on chloride was used. The results showed that a mixing process was the predominant factor to determine upstream APs concentrations; while the discharge of wastewater controlled the concentrations of APs downstream. Considering the adverse effect of APs on organisms, combined effect modeling was used to assess the toxicity to fish. It was found that the predicted mixture effect for APs in river water on fish vitellogenin induction was low upstream and medium downstream, respectively. 相似文献
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Li Y Zhang X Krasner SW Shang C Zhai H Liu J Yang M 《Journal of environmental monitoring : JEM》2011,13(10):2851-2857
Total organic bromine (TOBr) is a collective parameter representing all the brominated organic disinfection byproducts (DBPs) in water samples. TOBr can be measured using the adsorption-pyrolysis method according to Standard Method 5320B. This method involves that brominated organic DBPs are separated from inorganic halides and concentrated from aqueous solution by adsorption onto the activated carbon (AC). Previous studies have reported that some commonly known brominated DBPs can partially penetrate through the AC during this adsorption step. In this work, the penetration of polar brominated DBPs through AC and ozone-modified AC was explored with two simulated drinking water samples and one chlorinated wastewater effluent sample. Polar brominated DBPs were selectively detected with a novel precursor ion scan method using electrospray ionization-triple quadrupole mass spectrometry. The results show that 3.4% and 10.4% of polar brominated DBPs (in terms of total ion intensity) in the chlorinated Suwannee River fulvic acid and humic acid samples, respectively, penetrated through the AC, and 19.6% of polar brominated DBPs in the chlorinated secondary wastewater effluent sample penetrated through the AC. The ozone-modification of AC minimized the penetration of polar brominated DBPs during the TOBr analysis. 相似文献
939.
Black carbon (BC) is known as a strong sorbent for the sorption of planar hydrophobic organic compounds (HOCs), but there is very little information about the sorption of nonplanar HOCs on BC. In this study, the sorption of di-(2-ethyl-hexyl) phthalate (DEHP), one kind of nonplanar phthalate acid ester (PAE), by environmental BC collected from river sediments and pure BC (char-wood, char-stalk and soot-ash) was investigated. Strong and nonlinear sorption was observed for the sorption of DEHP on both pure BC and environmental BC with the Freundlich exponent ranging from 0.55 to 0.75 except for soot-ash, and the measured K(BC) (BC-water partition coefficient) of DEHP was about one order of magnitude higher than its organic carbon-water partition coefficient. There was a significant difference in sorption capacity among the environmental and pure BC. The presence of di-methyl phthalate (DMP) could significantly decrease the sorption of DEHP on BC, especially for environmental BC. In addition, the contribution of BC to the total sorption of DEHP on original river sediments was more than 50% when the equilibrium concentration of DEHP was less than 10 μg L(-1). This study indicated that ortho-substituted nonplanar PAEs could also be strongly sorbed by BC, and the difference in sorption among the BC samples revealed that it is important to take the source of BC into account when assessing its effects on the fate of HOCs in aquatic environment. 相似文献
940.
Xu P Wang W Yang L Zhang Q Gao R Wang X Nie W Gao X 《Environmental monitoring and assessment》2011,179(1-4):443-456
Aerosol size distributions, trace gas, and PM(2.5) concentrations have been measured in urban Jinan, China, over 6 months in 2007 and 2008, covering spring, summer, fall, and winter time periods. Number concentrations of particles (10-2,500 nm) were 16,200, 13,900, 11,200, and 21,600 cm(?-3) in spring, summer, fall, and winter, respectively. Compared with other urban studies, Jinan has higher number concentrations of accumulation-mode particles (100-500 nm) and particles (10-2,500 nm), but lower concentrations of ultrafine particles (10-100 nm). The number, surface and volume concentrations, and size distributions of particles showed obvious seasonal variation and are also influenced by traffic emissions. Through correlation analysis, traffic emissions are proposed to be a more important contributor to Atkien-mode and accumulation-mode particles than coal firing. Around midday, the presence of nanoparticles and new particle formation is limited to pre-existing particles from traffic emissions and the mass transport of particles from suburban and rural areas. Compared with other studies in urban areas of Europe and the USA, the variation of particle number concentration and related gas concentration in Jinan between weekdays and weekends is smaller and the reasons has been deduced. 相似文献