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981.
Environmental Science and Pollution Research - Thermal treatment of mercury (Hg)-contaminated soil was studied to investigate the desorption behavior of Hg at different temperatures. The soil...  相似文献   
982.
综合客观地评价城镇区域生态承载状况是中国快速城镇化进程中经济与环境协调发展的保障。传统生态承载力测度法仍偏向于将区域作为封闭系统来研究,但现实中区域生态系统是和外界相沟通的,区域对承栽力的需求可外部化。为综合测度城镇生态承栽力,以生态经济学理论为依据,结合快速城镇化地域特点,构建了快速城镇化地域生态承载力评价模型,并以义乌市为例,对2005年-2007年的生态承载力状况进行了评价与分析。评价结果表明,义乌2005年-2007年的生态承载力值均大于1,以东莞市和惠州市两个典型城镇的生态承载力值为参比值,与其相比较后说明义鸟的生态承载力状况良好;但逐渐以过高的生态成本来换取经济增长,生态承载力值逐年降低,生态承载力状况逐年变差。评价结果较准确地反映了区域的实际情况,所提出的评价方法能较准确客观地评价快速城镇化地域的生态承栽力状况。  相似文献   
983.
本文重点研究了清洁生产推进机制,对清洁生产运行机制、技术机制、管理机制、政策机制进行研究和分析,对清洁生产的产生理论和运行管理进行分析。结论是,政策机制的关键是成功地实施技术机制和内部管理机制,在中国清洁生产的实施应该主导的政府执法机制,辅之以必要的经济激励和支持机制应激机制。  相似文献   
984.
This study examines the monetary value of social costs—private costs and negative externalities—that could be avoided by energy conservation actions. A novel Air Resource Co-Benefits (ARCoB) model has been developed in this study to assess the comprehensive social benefits of greenhouse gas GHG mitigation policy. The rollback model is used to estimate changes in air pollutant concentrations attributed to the emission reductions. Change in ozone concentration is converted from non-methane hydrocarbons based on the maximum ozone increment reactivity. In addition to saved medical expenditure, years of potential life lost (YPLL) is estimated based on the exposure-response coefficients for mortality and is calculated with abridged life table. Two cases of energy efficiency improvement in different scales are analyzed to estimate the annual co-benefits of abatements of air pollutants and greenhouse gas in 2009: 1) the energy intensity reduction in the industrial sector and 2) energy saving at Taipei Taiwan City Hall. Results indicate the saved energy cost accounted for 66 % and 70 % in the first and second case, respectively, and was a major part of the total benefit from energy conservation. The saved air pollution fee was 7.8–8.5 times lower than the averted health cost of medical expenditure, which was US$10.34 million in the first case, in which there were also averted YPLL of 3,478 person-years or averted deaths of 311 persons per year.  相似文献   
985.
用食藻虫引导沉水植物生态修复工程技术对上海市临港新城果园镇里塘河道富营养化水体进行了工程治理和生态修复,辅以种植沉水植物,采取开放式生态修复和治理。每月水质跟踪检测结果表明:该工程治理方法具有显著生态修复效果,水质得到明显改善;CODMn、TN、TP在最低平均值时分别比生态修复前下降了60.67%、85.36%、88.74%;氨氮、亚硝态氮和叶绿素a在生态修复中的最低平均值分别为0.088 mg/L、0.024 mg/L和5.31 mg/m3;试验期间,修复区水体TN、TP、NO2-N、NH4-N和CODMn显著低于对照区,水体透明度(SD)平均为150~180 cm,水质达到国家Ⅱ~Ⅲ类地表水水质标准。  相似文献   
986.
Biotrickling filters (BTFs) for hydrophobic chlorobenzene (CB) purification are limited by mass transfer and biodegradation. The CB mass transfer rate could be improved by 150 mg/L rhamnolipids. This study evaluated the combined use of Fe3+ and Zn2+ to enhance biodegradation in a BTF over 35 day. The effects of these trace elements were analysed under different inlet concentrations (250, 600, 900, and 1200 mg/L) and empty bed residence times (EBRTs; 60, 45, and 32 sec). Batch experiments showed that the promoting effects of Fe3+/Zn2+ on microbial growth and metabolism were highest for 3 mg/L Fe3+ and 2 mg/L Zn2+, followed by 2 mg/L Zn2+, and lowest at 3 mg/L Fe3+. Compared to BTF in the absence of Fe3+ and Zn2+, the average CB elimination capacity and removal efficiency in the presence of Fe3+ and Zn2+ increased from 61.54 to 65.79 g/(m3?hr) and from 80.93% to 89.37%, respectively, at an EBRT of 60 sec. The average removal efficiency at EBRTs of 60, 45, and 32 sec increased by 2.89%, 5.63%, and 11.61%, respectively. The chemical composition (proteins (PN), polysaccharides (PS)) and functional groups of the biofilm were analysed at 60, 81, and 95 day. Fe3+ and Zn2+ significantly enhanced PN and PS secretion, which may have promoted CB adsorption and biodegradation. High-throughput sequencing revealed the promoting effect of Fe3+ and Zn2+ on bacterial populations. The combination of Fe3+ and Zn2+ with rhamnolipids was an efficient method for improving CB biodegradation in BTFs.  相似文献   
987.
德育教育是素质教育的核心内容,在整个素质教育中处于首要的地位。加强学校的德育工作,具有十分重要的意义。长期以来,教育界人士不断探索学校德育工作的新方法、新思路,本文仅就学生舍务管理,从加强管理队伍的素质,管理方法的科学化、人性化两个层面阐述舍务管理在学校德育中的重要作用。  相似文献   
988.
Aerosol composition change between dust storm and non duststorm periods is studied using the TSP (Total SuspendedParticulate) data measured at Gosan, Korea between 1992 and1999. The concentrations of elements measured between 1993and 1996 and those of ions between 1992 and 1999 duringdust storms are compared with those during non-dust stormperiods in spring (March, April, and May). Among theanalyzed ions, the concentrations of crustal species(potassium, calcium, magnesium, and chloride) andanthropogenic species (nitrate and non-sea salt (nss)-sulfate) increased when dust storm occurs while those ofammonium and sodium did not increase. Among the analyzedelements, the concentrations of crustal species (Fe, Al,Ca, Ti, and Zn) increased when dust storm occurs whilethose of anthropogenic species (Mn, V, Ni, Cu, Cd, and Cr)did not increase. The only anthropogenic element of whichconcentration increased during dust storm periods was Pb.It was found that the concentrations of nitrate and nss-sulfatewere highest during spring. Also, the ratio of theyearly average concentrations of nitrate to nss-sulfateincreases, probably due to the emission trend change innortheast Asia, especially, in China.  相似文献   
989.
990.
利用模拟除磷菌生存环境的两相法,设计厌氧-好氧两相交替条件,配合厌氧相含底物无磷培养基和好氧相含磷无底物培养基,进行高效除磷菌的筛选和菌株除磷能力检测.两相法包括前期富集、筛选、检测前驯化和检测共四个阶段.采用两相法从运行良好的SBR反应器中筛得15株菌,所有菌株均具有除磷能力,菌株除磷能力强.两相法筛选除磷菌具有针对性强,工作量小,筛选获得的菌株多样性好和高效除磷菌比例高等优点.  相似文献   
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