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131.
Tea saponin (TS), a kind of green biosurfactant produced by plants, was added into the Cd–pyrene co-contaminated soils to evaluate its influence on phytoremediation of Cd and pyrene by Lolium multiflorum. The results showed that the accumulation of pyrene in L. multiflorum was significantly promoted by the TS. Compared with no TS treatments (PL and ML), the aboveground concentrations of pyrene in TS treatments (PLT and MLT) increased by 135 and 30%, respectively, and the underground concentrations of pyrene in TS treatments (PLT and MLT) increased by 40 and 25%. The concentrations of Cd in the aboveground and underground parts in single contaminated treatments were all significantly more than those in co-contaminated treatments, while the situation of pyrene was quite the reverse. Besides, the addition of TS enhanced activities of dehydrogenase and polyphenol oxidase in soils and increased the biomass of L. multiflorum. The micromorphology of L. multiflorum was not affected by TS. The study suggests that the use of L. multiflorum with TS is an alternative technology for remediation of Cd–pyrene co-contaminated soils.  相似文献   
132.
于2014年4-9月,研究我国一典型南方水源溶解性有机物(DOM)的荧光特性变化与去除情况,同时分析了DOM荧光组分与三氯乙醛生成势(CHFP)的相关性。结果表明,该水源DOM主要以芳香性蛋白质类物质组成,溶解性微生物代谢产物类物质、富里酸类物质和腐殖酸类物质含量逐渐增加;5个荧光区域的积分体积(ΦⅠ,n、ΦⅡ,n、ΦⅢ,n、ΦⅣ,n和ΦⅤ,n)所占总体积(ΦT,n)平均比例依次为:13.55%、27.53%、25.00%、16.02%和17.91%;原水DOM的CHFP范围为27.06~81.20μg/L,平均值为46.60μg/L,三氯乙醛(CH)前体物含量与水体中溶解性微生物代谢产物类物质相关性最好;与常规处理工艺相比,O3/BAC深度处理工艺对于溶解性微生物代谢产物类物质的去除率大幅提高,更有利于CH的控制。  相似文献   
133.
Three diesel fuels, one oil sand-derived (OSD) diesel serving as base fuel, one cetane-enhanced base fuel, and one oxygenate [diethylene glycol dimethyl ether (DEDM)]-blended base fuel, were tested for their emission characterizations in vehicle exhaust on a light-duty diesel truck that reflects the engine technology of the 1994 North American standard. Both the cetane-enhanced and the oxygenate-blended fuels were able to reduce regulated [CO, particulate matter (PM), total hydrocarbon (THC)] and nonregulated [polyaromatic hydrocarbons (PAHs), carbonyls, and other volatile organic chemicals] emissions, except for nitrogen oxides (NO(x)), compared with the base fuel. Although burning a fuel that contains oxygen could conceivably yield more oxygenated compounds in emissions, the oxygenate-blended diesel fuel resulted in reduced emissions of formaldehyde along with hydrocarbons such as benzene, 1,3-butadiene, and PAHs. Reductions in nitro-PAH emissions have been observed in both the cetane-enhanced and oxygenated fuels. This further demonstrates the benefits of using a cetane enhancer and the oxygenated fuel component.  相似文献   
134.
Remote sensing was used to assess the impacts of tourism development on temporal land-cover changes in the Lugu Lake region, home to the Mosuo people. The ecological and economic significance of the Lugu Lake area derives from the existence of a unique matriarchal system and the success of tourism development. Temporal land-cover changes between 1990 and 2005 were evaluated using digital interpretation of multitemporal Landsat TM images. Pairwise comparison methods were used to quantify changes in land-cover during three periods: 1990 to 1995, 1995 to 2001, and 2001 to 2005. The areas surveyed in each period were 10,226 ha, 7,727 ha and 9,344 ha, respectively. The annual rate of land-cover change for farmland, forest, grassland and wetland were 2.86%, 5.85%, 3.95%, 6.28%, respectively. Farmland and wetland have decreased, whereas forest, grassland and residential areas have increased. The land-cover changes could be explained by the success of tourism development and ecosystem management in Lugu Lake region. The impact of tourism on land cover and the community environment were assessed. The results show that most farmers actively left farms for off-farm jobs and took measures to protect forest, grassland and wetland by developing tourism in the study area. However, construction in residential areas has proceeded in a disorderly fashion. In future, the potential impacts of tourism on the lake ecosystem need to be re-assessed and monitored.  相似文献   
135.
Environmental Science and Pollution Research - This paper investigates volatility spillovers between the global crude oil market and the stock markets of the global oil stock markets (Russian,...  相似文献   
136.
Environmental Science and Pollution Research - Global prevalence trend and regional differences of coal worker’s pneumoconiosis (CWP) remain unclear. This study aimed to provide systematic...  相似文献   
137.
Environment, Development and Sustainability - Cyanobacteria are a group of diverse prokaryotes that are capable of oxygenic photosynthesis. They are ubiquitous in nature and have been reported to...  相似文献   
138.
Environmental Science and Pollution Research - Electricity generation is the largest sector with decarbonization potential for China and the world. Based on the new emission factors, this paper...  相似文献   
139.
Environmental Science and Pollution Research - The aerodynamic noise around the high-speed railway bridge is studied by the train-bridge-flow field numerical model and theory analysis. With the...  相似文献   
140.
Environmental Science and Pollution Research - The traditional mixing ventilation is not an energy effective approach to remove indoor air pollutants, maintain breath zone air quality, and control...  相似文献   
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