PCR-DGGE技术对城市餐厨垃圾堆肥中细菌种群结构分析

使用基于16S rDNA的PCR-DGGE(变性梯度凝胶电泳)技术对城市餐厨垃圾堆肥过程中细菌种群结构随时间的变化进行了研究.在堆肥不同时间取样,进行了堆肥温度、pH、含水率、有机质、C/N的变化分析和DGGE分析.结果显示,堆肥温度高于50℃的天数为7d,最高达65℃,可有效杀灭致病菌;最终pH值接近7.5;C/N为20.04.PCR-DGGE图谱显示,不同时间堆肥样中细菌DGGE图谱有着明显的差异性;堆肥升温期细菌种群丰富,优势种群不明显;高温期细菌种群减少,优势种群明显;降温期细菌种群结构基本保持稳定.温度对堆肥过程中细菌种群具有明显的筛选作用.堆肥各阶段DGGE图谱相似性Cs值比较低,堆肥处理后细菌种群结构与堆肥原料之间存在明显差异.     

壳聚糖改性粘土去除城市湖泊中藻类的研究

对壳聚糖改性粘土用于城市湖泊中藻类的絮凝去除进行了研究。实验表明,粘土经过壳聚糖改性后,对高藻水中藻细胞的去除效能得到很大的提高。相比单独投加壳聚糖,粘土的加入增加了絮体密实度,减少了絮体体积,并使絮体分布更均匀。在壳聚糖与粘土配比为1∶20时,叶绿素的去除率和浊度的去除率均为最佳。粘土的种类对除藻效果有一定影响,其中以高粘凹凸棒石为最佳,在最佳投加量28 mg.L-1时,对叶绿素的去除率达到96.2%;粘土的粒径对絮凝效果基本没有影响,在粒径为60μm与300μm之间改性粘土对藻细胞的凝聚效果是一致的。经壳聚糖改性的粘土在酸性条件下絮凝效果较好,当pH值大于7时,其絮凝能力迅速下降。     

Environmental flows and its evaluation of restoration effect based on LEDESS model in Yellow River Delta wetlands

Due to freshwater supplement scarcity and heavy human activities, the fresh water wetland ecosystem in Yellow River Delta is facing disintegrated deterioration, and it is seriously affecting the health of the Yellow River ecosystem. This paper identifies the restoration objectives of wetland aiming to protect ecological and economic values and development as well as the water resources of the Yellow River. The hydraulic and groundwater coupling model and Landscape Ecological Decision and Evaluation Support System (LEDESS) of the Yellow River Delta were established to calculate environmental flows of degraded wetlands. LEDESS is a computer-based model developed and used to assess and evaluate the effects of land-use changes on nature. In this study, LEDESS is used to assess and evaluate the ecological effects and the restoration possibilities considering several environmental flows’ supplement scenarios. This included the changes of suitable habitat conditions and its ecological carrying capacities for indicator species, e.g., Red-crowned crane (Grus japonensis), Oriental stork (Ciconia boyciana), and Saunder’s gull (Larus relictus), and changing of ecological patterns. The results showed that replenishing fresh water to wetlands is one of the effective adaptive measures to mitigate wetland degradation and improve its habitat quality and carrying capacities. This study indicated that landscape ecology approach is not only considered as a good way to solve complex problems in ecosystem management but also can be used to decide on the environmental flows and assess its ecological effects in large-scale wetland rehabilitation. This integrated method could make environmental flows estimated and assessment more rational than the results of hydrologic methods. It could assist decision makers to “see” the ecological effects after water supplementing and so alleviate the contradictions between environmental flows and production water demands, and can facilitate the implementation of environmental flows in most countries with water resources shortage.     

常温UASB装置设计与运行控制

五粮液集团白酒生产销售居全国同行业之首，根据白酒生产的工艺技术和水质特性选择UASB－UBF－SRB工艺处理，运行效果达到国家规定的排放标准，文章着重介绍五粮液集团某车间废水处理站厌氧处理系统四季中各种参数的协调运行控制。     

21世纪城市生活垃圾生态化处理展望

我国目前由于管理,经济,技术以及公众环境意识的薄弱,城市生活垃圾已成为污染环境的一大公富,大致使大量有用资源浪费,就生态城市建设中垃圾生态化处理的重要性和对策进行了探讨,以期推动我国城市生活垃圾生态化处理和生态城市建设工作的开展。     

采用絮凝—接触氧化法处理酿酒行业废水

采用絮凝-接触氧化法处理酿酒行业废水,原废水CODcr浓度为1627-2334mg/L,SS浓度为2095-2301mg/L,BOD5浓度为981-1005mg/L,色度为80-110倍,用絮凝-接触氧化法处理后,CODer浓度为280-295mg/L,SS浓度为178-199mg/L,CODcr浓度为145-150mg/L,色度为20-25倍,CODcr平均去除率为85%。悬浮物平均去除率为91%,BOD5平均去除率为85%,色度平均去除率为77%,各项指标符合国家排废标准。     

阻尼降噪材料的研究进展

阻尼降噪材料作为一类功能环保材料,因其优越的减振、抗冲击、隔噪声性能而获得广泛应用,介绍了阻尼降噪材料的作用机理,综述了聚合物基阻尼降噪材料、金属类阻尼降噪材料、阻尼降噪复合材料及其他阻尼降噪材料的研充进展,分析了阻尼降噪材料住未来的发展趋势。     

阴离子表面活性剂测量因素的探讨

针对亚甲蓝分光光度法测定阴离子表面活性剂较难处理的乳化现象,采用破乳剂－异丙醇消除,方法回收率良好,准确度为95％－105％。     

Characteristics and sources of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Shanghai, China

A field campaign was conducted to measure and analyze 13 polycyclic aromatic hydrocarbons (PAHs) in six major zones in the city of Shanghai, P.R. China from August 2006 to April 2007. Ambient air samples were collected seasonally using passive air samplers, and gas chromatography–mass spectroscopy was used in this field campaign. The results showed that there was a sequence of 13 PAHs at Phen > FA > Pyr > Chr > Fl > An > BaA > BbFA > BghiP > IcdP > BkFA > BaP > DahA and the sum of these PAHs is 36.01 ± 10.85 ng/m³ in gas phase. FL, Phen, FA, Pyr, and Chr were the dominant PAHs in gas phase in the city. They contributed 90% of total PAHs in the gas phase. Proportion of measured PAHs with three, four, five, and six rings to total PAHs was 53%, 42%, 3%, and 2%, respectively. The highest concentration of ΣPAHs (the sum of 13 PAHs) occurred in the wintertime and the lowest was in the summer. This investigation suggested that traffic, wood combustion, and metal scrap burn emissions were dominant sources of the concentrations of PAHs in six city zones compared with coal burning and industry emissions. Further, the traffic emission sources of PAHs in the city were attributed mostly to gasoline-powered vehicles compared with diesel-powered vehicles. It was revealed that the seasonal changes in PAHs in the city depended on different source types. Metal scrap burn was found to be the major source of PAHs during the autumn, while the PAH levels in the atmosphere for winter and spring seasons were mainly influenced by wood and biomass combustion. Comparisons of PAHs among different city zones and with several other cities worldwide were also made and discussed.     

Investigation of indoor environmental quality in Shanghai metro stations, China

A field study was carried out in Shanghai metro stations to gather and evaluate information about the real environment. The thermal environment and particulate matter levels were monitored in this study. The mean thermal sensation vote in metro stations was 0.91, and the mean thermal neutral temperature was 20.6°C. Although 92.1% of subjects voted that the thermal environment was acceptable, the condition of air quality in Shanghai metro stations was not good. The mean levels of PM1.0, PM2.5, and PM10 were 0.231 ± 0.152, 0.287 ± 0.177, and 0.366 ± 0.193 mg/m³, respectively. The contribution of PM1.0 to PM2.5 and PM2.5 to PM10 was up to 79% and 76%, respectively. This means that fine particles or ultrafine particles constituted the preponderant part of metro station particulate matter.