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361.
重庆市区灰霾天气变化及特征分析   总被引:1,自引:0,他引:1  
分析了近15年重庆市区灰霾的时间变化特征以及主要大气污染物与能见度的相关性。1997—2012年,灰霾天气占41.2%,发生天数没有明显变化,严重程度有所减缓。灰霾在冬季发生的天数最多,持续时间长,且容易发生重度的持续灰霾。夏季灰霾天数最少,程度最轻。PM10、PM2.5、SO2、NO2浓度随灰霾的加重而增加,其中PM2.5浓度增幅最大,O3浓度随灰霾的加重而降低。灰霾对能见度的影响大于降水天气对其的影响。灰霾天气下能见度受PM2.5的影响较大,非灰霾天气下,能见度主要受O3的影响。  相似文献   
362.
Endocrine-disrupting compounds (EDCs) are exogenous substances that cause adverse health effects in an intact organism, or its progeny, subsequent to the changes in endocrine function. Recent studies have shown that wastewater treatment plant effluents play an important role in the release of EDCs into aquatic environments. Therefore, in this study, influent and effluent samples from three different wastewater treatment plants (WWTPs) in Istanbul were analysed for the presence of the principal EDCs. These chemicals include steroids and synthetic organic chemicals. Thus, the occurrence and fate of EDCs of great health concern were monitored at three WWTPs in Istanbul. Furthermore, these WWTPs are employing different treatment processes. Therefore, the EDC removal performances of different treatment regimes were also evaluated. Phytosterol was the most abundant EDC in the influent samples. Second group of compounds at high influent levels were alkyl phenols. Pesticide levels of all three WWTP influent samples were low. Pasakoy Advanced WWTP is more effective at eliminating EDCs. Kadikoy Primary WWTP exhibits the lowest EDC elimination efficiencies. To the best of our knowledge, this work comprises the first detailed report on the occurrence and behaviour of both natural and synthetic EDCs in WWTPs of Istanbul and Turkey. The steroid estrogen levels of this study are higher than the previously documented values, except the levels given for Gaobeidian WWTP in Beijing, China. This is attributed to higher population densities of Beijing and Istanbul and as well as to lower individual water consumption rates in the two cities.  相似文献   
363.
嗜热菌生物过滤技术处理高温废气的研究进展   总被引:2,自引:1,他引:1  
张馨月  王灿  季民 《化工环保》2011,31(1):34-37
介绍了嗜热菌的特点及其潜在优势,针对高温废气中的主要污染物(硫化氢气体、芳香族挥发性有机物(VOCs)、脂肪族VOCs),详细阐述了嗜热菌生物过滤技术对高温废气的处理性能及研究进展.分析了嗜热菌生物过滤技术有待进一步研究的科学问题,并展望了嗜热菌生物过滤技术的发展方向及前景.  相似文献   
364.
山东省水泥行业CO_2减排关键技术的实施分析   总被引:1,自引:1,他引:0  
由于社会对水泥需求的不断增长,多年来山东省水泥工业一直处于快速发展时期。作为国民经济的基础工业同时也是高耗能行业,山东省水泥行业面临着巨大的CO2减排压力。同时,技术自身的先进性决定了其相应的减排潜力,而减排效果的实现程度则取决于技术的推广度。在技术的推广过程中,其减排潜力、减排成本以及相关的政策支持都是关键性的影响因素,针对技术实施障碍进行深入的分析和探讨对实际减排效果的预测具有重要的意义。本研究利用长期能源替代规划系统软件建立了LEAP-Shandong Cement模型,对山东省水泥行业的CO2排放量及相应的减排潜力进行了模拟评估。到2020年,相对于基准情景,政策情景和技术情景下的减排潜力分别为8.2%和15.6%。山东省水泥行业实现减排主要依靠窑型的替代和相应技术的进步,其中余热发电技术改进为近期的重点减排技术,在水泥行业减排兼具显著的环境、经济和社会效益。  相似文献   
365.
用振荡平衡方法,研究了非离子表面活性剂Brij35和Brij30在沉积物上的吸附行为及其对甲基对硫磷在三种沉积物上吸附的影响.结果表明:Brij35的吸附符合Langmuir型吸附等温线;Brij30的吸附符合S型吸附等温线.对于有机质含量高的沉积物,Brij35抑制甲基对硫磷的吸附,Brij30在加入浓度大于CMC时能促进甲基对硫磷的吸附,低于CMC时则抑制甲基对硫磷的吸附.对于有机质含量低的沉积物,Brij35和Brij30均能使甲基对硫磷的吸附量增加.表面活性剂对甲基对硫磷吸附行为的影响机理为吸附态和溶解态的表面活性剂对甲基对硫磷的吸附和增溶共同作用的结果,表面活性剂吸附态对甲基对硫磷吸附的贡献主要来自于吸附并集聚于沉积物表面的表面活性剂,通过分配作用进入沉积物有机质的表面活性剂吸附态贡献率小.  相似文献   
366.
对开封市城区夏季噪声进行了监测,发现开封城区区域噪声污染严重,昼间57%的区域处在“重度污染”,夜间较昼间好,交通道路噪声所有监测路段均超标,尤其在交通主干道上污染严重,昼间有40个测点超标10dB以上。在开封城区噪声现状分析的基础上,运用G1S软件Mapinfo6.0绘制出开封市城区夏季噪声评价图,结果表明:开封市城区区域噪声污染南部比北部严重,交通噪声分布有城区向城市边缘逐渐恶化的趋势,且交通噪声与区域噪声没有明显的相关性。这主要是由于城市规划不合理、城市道路过窄、路况不好以及城市交通管理落后等原因造成的。最后提出了开封噪声污染防治的一些措施。  相似文献   
367.

The variations of phytoplankton functional groups and their correlation with environmental factors, as well as the applicability of phytoplankton functional groups to serve as biological water quality indicator in the Pearl River, South China, were studied in the present study. A total of 96 samples were collected and divided into 21 functional groups from September 2016 to July 2017. The phytoplankton functional groups P and G were dominant during the investigation, and their biomass contributing was ranged 0.06 to 89.07%, the average 30.73%, and ranged 1.47 to 62.40%, the average 9.33% of the total biomass, respectively. The results showed environmental estrogens—BPA (bisphenol A), E2 (17β-estradiol), E1 (estrone), 4-t-OP (4-tert-octylphenol), 4-NP (nonylphenol), TCS (triclosan), and TCC (triclocarban)—in the Pearl River were significantly different, and with average values of 269.30 ng L?1, 2.76 ng L?1, 4.24 ng L?1, 53.68 ng L?1, 952.72 ng L?1, 16.79 ng L?1, and 8.61 ng L?1, respectively. This was likely responsible for the differences in the phytoplankton functional groups. We observed positive correlations between P and A, and G and J. Functional groups P biomass decreased significantly with functional groups LM increased, and functional groups M and J with X2. We found positive correlations between functional group G and concentrations of E1 and TCC; functional group A and total nitrogen (TN), 4-NP, 4-t-OP, and E2; functional groups LM and L1 and total suspended particles, BPA, and TCS; and functional group G and negative total phosphorus (TP), pH, and TCS. The study showed that TN, TP, and the environmental estrogens in the aquatic ecosystems were correlation with phytoplankton functional groups type, and affected the ecological balance in aquatic environments.

  相似文献   
368.
The aim of this study is to increase biogas production and methane yield from landfill leachate in anaerobic batch reactors by using low frequency ultrasound as a pretreatment step. In the first part of the study, optimum conditions for solubilization of organic matter in leachate samples were investigated using various sonication durations at an ultrasound frequency of 20 kHz. The level of organic matter solubilization during ultrasonic pretreatment experiments was determined by calculating the ratio of soluble chemical oxygen demand (sCOD) to total chemical oxygen demand (tCOD). The sCOD/tCOD ratio was increased from 47% in raw leachate to 63% after 45 min sonication at 600 W/l. Non-parametric Friedman’s test indicated that ultrasonic pretreatment has a significant effect on sCOD parameter for leachate (p < 0.05). In the second part of the study, anaerobic batch reactors were operated for both ultrasonically pretreated and untreated landfill leachate samples in order to assess the effect of sonication on biogas and methane production rate. In anaerobic batch reactor feed with ultrasonically pretreated leachate, 40% more biogas was obtained compared to the control reactor. For statistical analysis, Mann–Whitney U test was performed to compare biogas and methane production rates for raw and pretreated leachate samples and it has been found that ultrasonic pretreatment significantly enhanced biogas and methane production rates from leachate (p < 0.05) in anaerobic batch reactors. The overall results showed that low frequency ultrasound pretreatment can be potentially used for wastewater management especially with integration of anaerobic processes.  相似文献   
369.
砷污染土壤磷酸盐淋洗修复技术研究   总被引:5,自引:2,他引:3  
淋洗修复技术是治理砷污染土壤的一种高效快速方法.本研究通过砷污染土壤批量振荡淋洗实验,筛选出环境友好且高效的淋洗剂磷酸钾,系统分析液固比、淋洗时间、淋洗液浓度、p H对土壤中砷的去除效果的影响,确定磷酸钾的最佳淋洗条件.进一步以磷酸钾为基本淋洗剂,采用不同试剂和磷酸钾进行组合二步淋洗,探究最佳复合淋洗组合.结果表明,磷酸钾在浓度为0.5 mol·L-1、液固比为4 m L·g-1、淋洗时间为8 h及p H为4.3的淋洗条件下,单独使用磷酸钾进行淋洗时,土壤砷的去除率达到74.03%.当采用0.5 mol·L-1Na OH+0.5 mol·L-1KH2PO4进行复合二步淋洗时,可使土壤中砷的去除率提高到82.60%.  相似文献   
370.
通过对比研究尼罗河三角洲与长江三角洲重金属污染特征,结果发现前者多数重金属含量高于后者,且尼罗河三角洲富集指数EF值约为长江三角洲3倍。此外,两者重金属分布格局差异明显,尼罗河三角洲呈东西高、中间低的"马鞍形"分布。自阿斯旺建坝后,干旱气候条件和人类活动使得尼罗河三角洲泻湖演变为重金属沉积中心。与之相反,长江三角洲重金属含量向海沿程降低,季风降水和巨量水沙对污染物扩散能力较强,污染水平较低。与世界其他地区河口相比,尼罗河三角洲重金属污染属于中等水平,而长江三角洲属于中下水平。对比研究表明两三角洲重金属物污染分布规律差异与其独特的流域自然条件和人类活动方式有密切关系。  相似文献   
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