On-line enrichment and determination of polycyclic aromatic hydrocarbons in atmospheric particulates using high performance liquid chromatography with fluorescence as detector

Seven polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulates were determinated by high performance liquid chromatography (HPLC) with fluorescence detector using direction injection and an on-line enrichment trap column.The method simplified the sample pretreatment,saved time and increased the efficiency.With the on-line trap column,PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency.The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample.The limit of detection was 15.3-39.6 ng/L (S/N=3.3).There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970.Furthermore,it also indicated that the method is available to determine PAHs in atmospheric particulates well.     

双曲线自然通风冷却塔噪声治理设计

发电厂闭式循环冷却水系统是采用钢筋混凝土结构自然通风冷却塔,其噪声污染治理是一个难题。本文以攀钢电厂双曲线自然通风冷却塔为例,介绍其噪声特性、控制措施及治理效果。     

提高循环冷却水系统浓缩倍数的措施

根据水量平衡原则和水中溶解含盐量的平衡,从理论上对浓缩倍数的选择进行了探讨。结合实际情况,从设计、水质因素、管理等方面分析了影响浓缩倍数提高的原因,提出了提高浓缩倍数的措施、方法和水质稳定技术。     

热电冷联供系统在海上平台的应用

文章介绍热电冷联供系统的设备组成及其设计注意事项;介绍以燃气轮机为发电机组的热电冷联供系统案例。在热电冷联供系统中配置溴化锂吸收式制冷机,可充分发挥其利用低品位能源的优势;设计热电冷联供系统前,应进行必要的经济性分析,合理确定设备配置方案和配置容量;以燃气轮机发电机组和烟气型溴化锂吸收式冷热水机组为主要设备组成的热电冷联供系统,烟气系统的设计和安装连接是关键。文章可为燃气轮机热电冷联供系统的设计和建造提供技术参考。     

新型杀生剂与阻垢剂组合在城市污水回用中的应用

针对城市污水处理厂二级出水回用作循环冷却水补充水的工艺,采用新型杀生剂与阻垢剂组合进行了动态试验。加入药剂后腐蚀速率为0.00087g/（m^2·h）和0.00116g/（m^2·h）,缓蚀率在80%左右,表明该药剂能较好地控制铜管腐蚀。     

Preparation, characterization, and photocatalytic activities of boron- and cerium-codoped TiO2

Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribution （PSD）, diffuse reflectance spectra （DRS）, and Brunauer-Emmett-Teller （BET）. The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B （ARB）. The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B1.6Ce1.0-TiO2 prepared at 500℃ showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce^3＋ and Ce^4＋, and the atomic ratio of Ce^3＋/Ce^4＋ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range （〈526 nm）. As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels （Ce/Ti=2.0）. The particles size ranged from 122 to 255 nm with a domain at 168 nm （39.4%）. The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 （a standard TiO2 powder）. The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.     

海洋环境腐蚀模拟试验装置的优化设计与研制

本文介绍了基于GB/T 19746—2005/ISO 11130:1999等材料腐蚀性能试验标准的试验装置设计要求以及试验装置的主要组成。重点是添加了温度控制系统,优化了潮差控制系统,模拟了海洋波浪。本试验装置是一种结构简单、能够较真实模拟海洋环境腐蚀的试验装置。该试验装置研制成功,为研究海洋用材料的腐蚀行为与机理提供重要的技术设备支持。     

沸石生物滤池处理低浓度生活污水的工艺性能及影响因素

为将电厂低浓度生活污水处理后回用于循环冷却水,开发了沸石滤料曝气生物滤池(ZBAF)工艺,在直径0.2m、滤料高3m的ZBAF装置中处理低浓度生活污水.结果表明,在温度为12℃～17℃,停留时间1.4h,气水比4:1,进水浊度、BOD₅、COD_Cr和NH₄⁺-N分别为59NTU、30mg/L、81mg/L和16mg/L时,相应的出水指标为3.2NTU、3.2mg/L、14.5mg/L和0.5mg/L,满足再生水用作循环冷却补充水的水质标准.改变水力停留时间和气水比对BOD₅、COD_Cr和浊度去除率影响不大,但对NH₄⁺-N去除率影响较大.生物相观察发现:反应器内脱碳/硝化区(C/N区)生物相很丰富,其中固着型纤毛虫很多;而硝化区(N区)生物相比较单一,主要为硝化菌.固着型纤毛虫数量明显减少处为2个区的分界线.     

宽域灰色聚类法在土壤环境质量评价中的应用

利用宽域灰色聚类法评价土壤环境质量,先构造白化函数,引入修正系数,确定污染物权重,再计算聚类系数实现土壤样本的环境质量等级评判与排序。将此方法应用于太原市5个区县,8项指标的土壤质量评价,并与综合指数法、模糊综合评判法相比较,结果表明模糊综合评判法与宽域灰色聚类法对于5个区县的污染级别的评价结果是一致的,而综合指数法对前四个评价点级别均比上述两种方法低一个级别,三种方法的质量排序大致相同,只有模糊综合评价中认为小店区优于万柏林区。     

人工神经网络结构对径流预报精度的影响分析

建立了基于径流形成机理的以时段降水量与前期径流量为预报因子的前向多层人工神经网络径流预报模型；分析了网络结构对月径流预报精度的影响，发现随网络结构的复杂化，网络训练误差减小，模型评定的确定性系数增大，并均趋于稳定，预报检验的确定性系数总趋势是减小；发现影响模型精度的决定因素是网络输入单元数，亦即径流影响因素；提出了以模型评定与预报检验共同高效或等效的模型选择的折衷方法，以及按模型适宜预报域进行多模型组合预报的最佳预报域组合法。