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101.
基于PROMETHEEⅡ法的污染场地土壤修复技术筛选及应用   总被引:5,自引:0,他引:5  
依据当前污染场地土壤修复技术特点以及场地特征,构建4层12指标21方案的污染土壤修复技术决策分析结构,运用多属性决策分析方法——PROMETHEEⅡ偏好排序法,对当前场地修复技术以及典型场地条件进行了客观分析和综合评价,实现基于具体修复目标的污染场地土壤修复技术择优筛选,并采用该方法对虚拟特定污染场地的土壤修复技术筛选进行了实例应用。这为污染场地的治理和修复提供了方法依据和理论参考。  相似文献   
102.
The efficiency of aided phytostabilization using organic amendments such as ramial chipped wood (RCW) and composted sewage sludge (CSS) was studied on contaminated techno-soils, on nine experimental plots. The objective was to characterize the role of fulvic (FA) and humic acids (HA) on the mobilization of trace elements, specifically As, Cu, Mo, Pb and Zn. Results showed that the addition of CSS increased the total organic carbon and nitrogen content more than with RCW and as a result, the C/N ratio in the CSS soil was higher than in the RCW and non-amended (NE) soil, reflecting the high decomposition of soil organic matter in the CSS soil compared with the other soils. The RCW and CSS amendments increased the hydrogen index (HI) values and the oxygen index (OI) values compared with the NE soil, especially for the soil treated with CSS which contained more aliphatic than aromatic compounds. The addition of CSS to the techno-soil significantly increased the percentage of C org associated with the HA fractions compared with the RCW and NE soils. The soil amended with CSS showed the highest E 4/E 6 ratio and the lowest E 2/E 3 ratio of FA. Zn and As were more abundant in the FA fraction than in the HA fraction, whereas Pb, Cu and Mo were more associated to HA than to FA in the treated and untreated soils, which may explain the difference in their mobility and availability.  相似文献   
103.
A comparative study on Fe/Al, Fe/Al/Cu, and Fe/Al/Ni catalysts in high-temperature water–gas shift reaction (HT–WGS) using simulated waste-derived synthesis gas has been carried out. The metal oxide (Cu and Ni) and aluminum incorporated Fe catalysts were designed to get highly active HT–WGS catalysts. Despite the high CO concentration in the simulated waste-derived synthesis gas, Fe/Al/Cu catalyst exhibited the highest CO conversion (84 %) and 100 % selectivity to CO2 at a very high gas hourly space velocity (GHSV) of 40,057 h?1. The outstanding catalytic performance is mainly due to easier reducibility, the synergy effect of Cu and Al, and the stability of the magnetite.  相似文献   
104.
通过水培实验,研究钙对铬胁迫下李氏禾幼苗生理生化、草酸分泌及铬吸收量的影响,考察钙对李氏禾体内草酸合成的调控,进而促进李氏禾的铬耐性富集能力的作用。结果显示,不同浓度Cr3+胁迫下缺钙处理,李氏禾生长受抑制及质膜过氧化作用加剧,体内总草酸含量为对照处理的113%~169%,且主要表现为水溶性草酸含量显著高于对照,水溶性草酸含量为对照处理的135%~197%;高钙处理,李氏禾细胞膜透性、丙二醛(MDA)含量低于对照,李氏禾叶部总草酸含量为对照处理的125%~155%,且主要表现为不溶性草酸含量显著高于对照,其含量为对照处理的181%~270%。低浓度(0.2、0.4 mmol/L)铬胁迫下,高钙处理总铬含量分别为对照处理的175%和215%,高浓度(0.8、1.0 mmol/L)铬胁迫下,总铬含量与对照处理无显著差异(P>0.05)。可见,添加Ca2+能在一定Cr3+浓度胁迫下,有效缓解铬对李氏禾的毒害,且能通过提高植物体内不溶性草酸含量达到促进植物富集和耐受铬的能力。  相似文献   
105.
Photochemical degradation of fluoroquinolone ciprofloxacin (CIP) in water by UV and UV/H2O2 were investigated. The degradation rate of CIP was affected by pH, H2O2 dosage, as well as the presence of other inorganic components. The optimized pH value and H2O2 concentration were 7.0 and 5 mM. Carbonate and nitrate both impeded CIP degradation. According to liquid chromatography–tandem mass spectrometry analysis, four and 16 products were identified in UV and UV/H2O2 system, respectively. Proposed degradation pathways suggest that reactions including the piperazinyl substituent, quinolone moiety, and cyclopropyl group lead to the photochemical degradation of CIP. Toxicity of products assessed by Vibrio qinghaiensis demonstrated that UV/H2O2 process was more capable on controlling the toxicity of intermediates in CIP degradation than UV process.  相似文献   
106.
Release of domestic sewage leads to accumulation of xenoestrogens in holding waters, especially in closed or semi-enclosed waters such as lakes. In the study, the occurrence, distribution, estrogenic activity and risk of eight xenoestreogens were evaluated in Lake Donghu, China. Nonylphenol (NP), octylphenol (OP), and bisphenol A (BPA) were identified as the main xenoestrogens ranging from tens of ng L−1 (in the surface water) or ng g−1 dw (in the suspended particles and sediment) to tens of μg L−1 or μg g−1 dw. The sum of 17β-estradiol equivalents (∑EEQs) ranged from 0.32 to 45.02 ng L−1 in the surface water, 0.53 to 71.86 ng g−1 dw in the suspended particles, and 0.09 to 24.73 ng g−1 dw in the sediment. Diethylstilbestrol (DES) was determined as the main contributor to ∑EEQs followed by NP. The risk assessment showed a higher risk in the surface water than in the suspended particles and sediment in such domestic sewage-holding lake.  相似文献   
107.
诺氟沙星作为一种抗生素广泛应用于人类日常生活,并大量进入水体环境,给水环境质量和生态系统安全带来隐患。研究了由3种不同填料组成的水平流和复合垂直流生物活性滤床对诺氟沙星的去除效果,结果表明,在水力负荷为0.1m^3/(m^2·d)、进水诺氟沙星浓度为392.11—686.17μg/L(平均浓度为500.97μg/L)条件下,复合垂直流滤床对诺氟沙星去除效果普遍好于水平潜流滤床,以沸石为填料的复合垂直流生物活性滤床对诺氟沙星的去除效果最好,平均去除率为80.61%,说明选择合适填料和合适类型的生物活性滤床可以作为去除诺氟沙星的一种有效方法。  相似文献   
108.
光污染已经成为继水污染、大气污染、噪声污染、固体废物污染之后的第五大污染.是21世纪直接影响人类健康的又一环境杀手!  相似文献   
109.
对承德市热电厂CG35/3.82-MX型循环流化术锅炉的脱硫除尘系统进行了改造,解决了原水膜除尘器效率低,烟法排放严重超标的问题,取得了良好的环境效益,社会效益和经济效益。  相似文献   
110.
影响马尾松毛虫虫灾发生类型因素的重要性分析   总被引:4,自引:1,他引:3  
运用列联表分析方法探讨了小班的林地起源、优势树种、地理、生长等因素对小班的马尾松毛虫虫灾发生类型的影响。分析结果表明:小班的海拔高度和坡度是决定小班的马尾松虫灾发生类型的关键因素。小班的优势种结构、平均树高及郁闭度对小班的马尾松毛虫虫灾发生类型也有较大的影响。图12表1参2  相似文献   
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