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61.
定量研究经济社会发展对地区能源消费碳足迹的影响对区域实现低碳发展具有重要意义。论文计算了江苏省苏锡常地区1991-2008年能源消费碳足迹,采用岭回归函数对STIRPAT模型进行了拟合,采用脱钩指数分析了经济发展与能源消费碳足迹之间的关系。结果表明:①1991-2008年能源消费碳足迹平均增长速度为15.30%,能源消费碳足迹分配率以煤炭为主,石油所占比例呈波动下降趋势,天然气所占比例上升较快,能源消费碳足迹产值总体呈波动下降趋势;②经济增长是能源消费碳足迹的主要影响因素,两者关系模型拟合未出现环境库兹涅茨曲线;③经济增长与能源消费碳足迹之间处于相对脱钩与复钩的波动状态,从另一侧面验证了目前两者之间不存在库兹涅茨曲线假说的结论。  相似文献   
62.
北京转河河岸带生态修复对河流水质的影响   总被引:8,自引:5,他引:3  
李婉  张娜  吴芳芳 《环境科学》2011,32(1):80-87
以北京转河为例,探讨一系列河岸带生态修复措施(尤其是河漫地和护岸的改造)对河流水质的影响.于2009年7~9月进行实地调查,沿河岸选取13个采样点,并定期采集水样,测定其中营养物质和溶解氧(DO)等的浓度.结果表明,转河氨氮(NH4+-N)、硝氮(NO3--N)、总磷(TP)和DO的浓度均有非常明显的季节变化.在居民用...  相似文献   
63.
介绍了部分湿式氧化法的基本原理,指出COD去除率是判断是否部分湿式氧化的重要指标。用高压反应釜进行污泥处理,在一定的温度、压力和适合氧气量的条件下,考察了COD去除率、有机物降解率、pH值、过滤性能等随反应时间的变化。试验结果表明,通过控制反应时间,可以实现污泥的部分湿式氧化。考察了污泥经过部分湿式氧化后产物的性质,包括颗粒分布、有机物含量、养分含量和重金属等项目,分析结果表明,产物具有良好的资源化前景。  相似文献   
64.
试验考察了东阿县污水处理厂一期A2/O工艺厌氧池去除有机污染物效能,当进水ρ(COD)为548.3 mg/L时,厌氧池平均去除率达78.7%。同时探讨了几种常见数学模型模拟厌氧池去除有机物规律情况,根据实际工程监测数据确定有机底物降解动力学常数,得出Grau模型、Stover-kincannon模型和改进的Monod模型较适合模拟厌氧池去除有机物的规律,并对模型进行了检验。  相似文献   
65.
A new type of sponge iron sphere (NSIS) with 1-5 mm diameter, made of concentrated iron powder and possessed high activity and intension, was prepared by mini-pellet sintering integrated with H2 direct reduction. Static state experiment has been carried on to investigate the Cd2+ removal efficiency from wastewater by the NSIS and to explore the Cd2+ removal reaction kinetics. It was suggested that initial pH value and Cd2+ original concentration had significant influence on Cd2+ removal percentage. Cd2+ removal percentage decreased significantly with the increasing of Cd2+original concentration whether the original pH value be adjusted to 3.0 or without adjustment. The results showed that the Cd2+ removal process followed the first order reaction because the reaction order was from 0.803 to 0.996. The apparent reaction rate constant between Cd2+ and NSIS was from 0.0025 to 0.1000 (mg·L?1)1-n·min?1. Compared with SIS reduced by charcoal reduction, NSIS deoxided by hydrogen possessed higher activity, and could remove the same quantity of Cd2+ within a shorter period of time.  相似文献   
66.
酵母融合菌对Cr的吸附性能及机理分析   总被引:1,自引:0,他引:1  
研究了酵母融合菌R32对Cr的吸附性能及机理.结果表明,该菌对Cr(Ⅵ)有着很好的吸附效果,最佳吸附条件为pH≤3,投菌量为l0g/L(含水率(78±2)%),吸附温度30~35℃,Cr(Ⅵ)的初始浓度≤20mg/L.当Cr(Ⅵ)的初始浓度为10mg/L时,总铬及Cr(Ⅵ)的去除率达93.7%和96.5%,总铬的残留浓...  相似文献   
67.
利用空气质量自动监测系统分析了2011年春节期间鄂尔多斯市东胜区的SO2、NO2及PM10的浓度值,发现烟花爆竹的燃放对它们的浓度有较大影响。  相似文献   
68.
Organic acids as important constituents of organic aerosols not only influence the aerosols' hygroscopic property, but also enhance the formation of new particles and secondary organic aerosols. This study reported organic acids including C14–C32fatty acids, C4–C9dicarboxylic acids and aromatic acids in PM2.5collected during winter 2009 at six typical urban, suburban and rural sites in the Pearl River Delta region. Averaged concentrations of C14–C32fatty acids, aromatic acids and C4– C9 dicarboxylic acids were 157, 72.5 and 50.7 ng/m3, respectively. They totally accounted for 1.7% of measured organic carbon. C20–C32fatty acids mainly deriving from higher plant wax showed the highest concentration at the upwind rural site with more vegetation around, while C14–C18fatty acids were more abundant at urban and suburban sites, and dicarboxylic acids and aromatic acids except 1,4-phthalic acid peaked at the downwind rural site. Succinic and azelaic acid were the most abundant among C4–C9dicarboxylic acids, and 1,2-phthalic and 1,4-phthalic acid were dominant aromatic acids. Dicarboxylic acids and aromatic acids exhibited significant mutual correlations except for 1,4-phthalic acid, which was probably primarily emitted from combustion of solid wastes containing polyethylene terephthalate plastics. Spatial patterns and correlations with typical source tracers suggested that C14–C32fatty acids were mainly primary while dicarboxylic and aromatic acids were largely secondary. Principal component analysis resolved six sources including biomass burning, natural higher plant wax, two mixed anthropogenic and two secondary sources; further multiple linear regression revealed their contributions to individual organic acids. It turned out that more than 70% of C14–C18fatty acids were attributed to anthropogenic sources, about 50%–85% of the C20–C32fatty acids were attributed to natural sources, 80%–95% of dicarboxylic acids and 1,2-phthalic acid were secondary in contrast with that 81% of 1,4-phthalic acid was primary.  相似文献   
69.
Removal of noxious dyes is gaining public and technological attention. Herein grafting polymerization was employed to produce a novel adsorbent using acrylic acid and carboxymethyl cellulose for dye removal. Scanning electron microscopy and Fourier-transform infrared spectroscopy verified the adsorbent formed under optimized reaction conditions. The removal ratio of adsorbent to Methyl Orange, Disperse Blue 2BLN and malachite green chloride reached to 84.2%, 79.6% and 99.9%, respectively. The greater agreement between the calculated and experimental results suggested that pseudo second-order kinetic model better represents the kinetic adsorption data. Equilibrium adsorptions of dyes were better explained by the Temkin isotherm. The results implied that this new cellulose-based absorbent had the universaiity for removal of dyes through the chemical adsorption mechanism.  相似文献   
70.
生态经济城市通过城市生态、经济与社会系统的动态协调,形成一个生态高度有效保护、经济良性高效发展、人与自然和谐相处的整体功能系统,代表了现代和未来城市发展的方向.作为全国首批六个生态文明建设试点地区之一和广东省的生态发展区,韶关市加快生态经济城市建设符合这一发展潮流和趋势.根据SWOT分析方法,对韶关市生态经济城市建设面临的优势、劣势、机遇和挑战进行分析,不仅为韶关生态经济城市建设提供策略依据,而且为其它类似地区的生态经济城市建设提供借鉴.  相似文献   
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