崇明典型水生生物中雌激素含量和分布特征

采用超高效液相色谱串联质谱系统(UHPLC-MS2)检测崇明岛9种典型水生生物体中5种典型雌激素的含量,包括雌酮(E1)、雌二醇(E2)、雌三醇(E3)、炔雌醇(EE2)和双酚A(BPA).并探讨其分布特征,进行初步健康风险评价.结果表明,9种典型水生生物中雌激素总量(以dw计)为1.1~7.38 ng·g-1,平均为4.25 ng·g-1.雌激素脂肪含量(以lw计)在5.01~83.41 ng·g-1之间,平均值为40.75 ng·g-1,雌激素脂肪含量水平表现为鱼类>虾类>蟹类.鱼类和蟹类,虾类之间雌激素脂肪含量差异性显著,蟹类和虾类之间不存在显著差异性.从检出率和检出含量看,甾醇类雌激素(E1、E2、E3和EE2)的残留明显低于酚类雌激素(BPA).E1、E2、E3和EE2的检出率小于66.67%,平均干重含量为0.17~0.69ng·g-1,而BPA的检出率高达100%,检出的平均干重含量为2.60 ng·g-1.健康风险评估结果表明,崇明岛水产品中雌激素对健康影响不大.     

工业锅炉PM2.5产排特性试验研究

采用荷电低压颗粒撞击器(ELPI)对哈尔滨市两台燃用烟煤的工业锅炉PM2.5排放特性进行了研究.研究结果表明:PM2.5的粒数和质量浓度分布曲线均呈现单峰分布,前者峰值出现在0.12~0.2μm粒径范围内,这部分粒子主要是由无机物气化-凝结形成的亚微米颗粒物和挥发分未完全燃烧形成的炭黑粒子,而后者峰值出现在0.32μm处,粒子主要是由炭黑粒子形成的亚微米颗粒和残灰粒子形成的超微米颗粒.同时发现,旋风除尘和湿法除尘对PM2.5各级颗粒均有一定的去除效果,采用多管旋风和冲击水浴除尘器联合除尘效率比单种水膜除尘器除尘效率高;湿法脱硫系统对PM2.5的脱除也有明显的作用,由于除雾器不能全部去除小雾滴,这些雾滴中固体颗粒被干燥和水溶性物质结晶析出,PM0.32颗粒物粒数浓度有所增加,而PM0.32~2.5的颗粒物粒数浓度有所减少,但总质量浓度降低.     

污水处理厂絮凝剂最佳浓度的小试实践

聚丙烯酰胺作为絮凝剂在污水处理行业使用已很普遍,使用前通过精确小试更准确把握其使用浓度及使用量,可节约生产成本。本文介绍了一种简易的试验装置,用其测定得到污水处理厂絮凝剂的最佳使用浓度。     

利用3 nm~20 μm颗粒物粒径分布测量仪对南宁市大气颗粒物粒径分布特征进行研究

利用颗粒物粒径分布测量仪(particle size distribution system,PSD)对南宁市2016年11月15日—12月4日大气颗粒物进行实时监测,分析颗粒物数浓度、粒径分布特征及其与颗粒物质量浓度的关系.结果表明,南宁市3 nm~20μm颗粒物平均数浓度为3269个·cm-3,粒径呈双峰分布,主峰值出现在28 nm左右,次峰值出现在100 nm左右.颗粒物数浓度随时间变化呈现一定规律,即早上8:00—10:00和晚上18:00—20:00左右出现浓度高值,这与早晚高峰有关.新粒子一般在16:00~18:00左右开始生成,18:00—20:00左右逐渐长大,并在夜间至凌晨保持较高的浓度.南宁市监测期间新粒子生成与机动车尾气排放有关.颗粒物质量浓度越大对应的数浓度也相应较高,较大粒径颗粒物对质量浓度贡献较大.降雨和风速加大过程对颗粒物数浓度下降有影响;温度和湿度对颗粒物数浓度影响不明显.     

煤气生产车间CO气体浓度监控技术的研究

根据某化工厂煤气生产工艺流程,研究预防CO气体泄漏引起的火灾、爆炸和中毒事故的监控系统,分析监控系统的工作原理及电路图,对CO监控技术的研究和气体传感器的研制有重要的参考价值.     

典型木材燃料层流扩散火焰碳黑生成特性研究

为了对木材燃料层流扩散火焰碳黑生成特性进行研究,搭建了基于消光法原理的轴对称层流火焰碳黑浓度测量平台,选用马尾松针、柚木以及红橡木三种典型木材燃料粉碎成针状试样,并堆成直径3.5 cm堆垛,利用酒精引燃后可获得稳定的层流扩散火焰,同时通过电热丝辅助加热延长稳定燃烧。通过对三种典型木材燃料层流燃烧过程的质量损失和火焰碳黑浓度的测量和对比分析,结果显示三种燃料中马尾松针碳黑生成能力最大,这说明木材的碳黑生成能力可能与其碳元素和氧元素的含量有关。     

Prediction of Pb speciation in concentrated and dilute nutrient solutions

Despite the presence of numerous studies in the literature examining the phytotoxicity of Pb, there is a lack of precise quantitative data on limiting concentrations of Pb for plant growth. Using the PhreeqcI chemical equilibrium model, simulations were conducted to examine the speciation of Pb in concentrated and dilute nutrient solutions. Due to the higher P concentration of Hoagland's solution (1000microM), precipitation of chloropyromorphite (Pb5(PO4)3Cl) was predicted to occur at lower pH values, and at lower Pb concentrations, than for a dilute nutrient solution (2microM P). Although nutrient solutions prepared in the glasshouse were supersaturated (and Pb concentrations were substantially higher than predicted by modeling), they confirmed the importance of the P concentration in influencing the precipitation of Pb. Given the low solubility of Pb-phosphates, nutrient solutions with low P concentrations should be utilized, and plant growth should be related to measured Pb concentrations rather than to the quantity of Pb initially added.     

污水厂污泥一体化竖式强化渗滤浓缩自然干化与消化研究

针对目前国内污泥处理处置存在的问题,为实现污泥浓缩消化一体化,开发了污泥一体化强化渗滤浓缩自然干化与消化新工艺反应器,并进行了城市水厂污泥处理试验.结果表明,在有机负荷为0.8 kg VSS/(m3·d)、平均水力停留时间为8.3 d、污泥停留时间为120 d的条件下,污泥有机物去除率可达到44.4%,排泥含水率达到79.1%,污泥消化与浓缩过程起到了相互促进的作用.渗滤液须抽回至污水处理厂处理.     

Trends in airborne particulates in Stuttgart, Germany: 1972-2005

Since 1972, at the University of Hohenheim in Stuttgart, Germany, airborne particulate matter (PM12 and then PM10) was continuously collected on filters and analyzed for environmentally relevant elements by X-ray fluorescence analysis. The resulting long-term time series are suitable for the investigation of trends and of seasonal variation. For the period 1972-2005, monthly and annual concentration mean values of 13 elements (Br, Ca, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Ti, V, and Zn) in the air are presented. Trend curves were fitted and the mean yearly variation of the concentration for these elements was calculated and represented graphically. All trend curves show a diminution of the air pollution during this period, but to different extents. Mean trends in percent per year were calculated for each element both for the entire investigation period and for three data subsets of 10-11 years. Possible explanations are discussed in detail.     

Seasonal variation in dissolved gaseous mercury and total mercury concentrations in Juam Reservoir, Korea

Dissolved gaseous mercury (DGM) and total mercury (TM) concentrations were measured in Juam Reservoir, Korea. DGM concentrations were higher in spring (64+/-13pgL(-1)) and summer (109+/-15pgL(-1)), and lower in fall (20+/-2pgL(-1)) and winter (23+/-6pgL(-1)). In contrast, TM concentrations were higher in fall (3.2+/-0.1ngL(-1)) and winter (3.3+/-0.1ngL(-1)) than in spring (2.3+/-0.1ngL(-1)) and summer (2.2+/-0.4ngL(-1)). DGM concentrations were correlated with water temperature (p<0.0001), ORP (p<0.0001), UV intensity (UV-A: p=0.008; UV-B: p=0.003), and DOC concentration (p=0.0107). DGM concentrations varied diurnally with UV intensity. The average summer DGM (109+/-15pgL(-1)) and TM (2.2+/-0.4ngL(-1)) concentrations in Juam Reservoir were higher than the averages for North American lakes (DGM=38+/-16pgL(-1); TM=1.0+/-1.2ngL(-1)), but lower than levels reported for Baihua Reservoir in China.