烷基膦酸为载体的液膜中Pb(Ⅱ)的迁移

研究了在以烷基膦酸为载体的液膜中Pb(Ⅱ)的液膜迁移行为.探讨了料液相pH值、温度、载体浓度、金属离子浓度对Pb(Ⅱ)迁移率的影响实验结果表明,Pb(Ⅱ)的迁移率随温度和载体浓度的升高而逐渐增大当外水相pH值控制在2.8～4.0、温度为289K～303K、载体浓度为5.00%～7.00%时,Pb(Ⅱ)即可快速并完全迁移.     

含油污水处理技术应用实例

介绍了油田伴生气处理厂对含油污水进行处理的方法,采用新型油水分离技术对含油污水进行油水分离,使污水达标排放,解决了含油污水直接排放至原燃烧池的安全、环保问题,同时回收轻油,增加了经济效益。     

柱色谱法批量分离N-甲基-2-(3-硝基苯基)吡咯烷[3’,4’:1,2][60]富勒烯研究

经C60、N-甲基甘氨酸和间硝基苯甲醛反应得到N-甲基-2-(3-硝基苯基)吡咯烷[3′,4′∶1,2][60]富勒烯(MNPF)反应液,旋转蒸发干燥得质量分数为23%的MNPF粗品,采用柱色谱法批量分离其中的MNPF。确定了柱色谱法批量分离MNPF的最佳工艺条件:二硫化碳为流动相,柱层析用硅胶(37~48μm)为固定相,色谱柱直径5cm,高径比为6∶1,最大上样量为23 g。此时分离所得MNPF纯度达99%,回收率为92.3%。     

农田土壤中汞的吸附分配行为研究

汞是环境中毒性最强的重金属之一,由于具有持久性、长距离迁移性和生物累积性被列为全球性污染物。土壤是汞重要的源和汇,在汞的生物地球化学循环中发挥关键作用,其理化性质可以显著影响汞的吸附分配行为。本文基于采自全国各地的131份农业土壤样品考察了汞(Hg2+)在土壤中的吸附分配行为,测定了Hg2+的固液分配系数(Kd),并探讨其与p H、有机质(OM)、粒度组成、溶解性有机质(DOM)和总硫等土壤理化性质的关系。利用逐步多元线性回归的方法分析发现旱地土壤对汞Kd的主要影响因素是DOM和土壤粒度,而水田的主要影响因素是总硫。通过淹水实验,进一步探究了土壤氧化还原对Hg2+分配的影响。研究发现,旱地土壤中,大部分土壤在淹水30 d后Kd呈明显增大趋势,继续淹水至60 d的Kd表现为稳定或下降的趋势;大部分水田土壤在淹水条件下Kd未表现出增大的趋势,且随淹水时间呈稳定或下降的趋势。     

大型空分装置中空气透平压缩机的自动安全控制

简述大型空分装置的空气透平压缩机的自动控制原则,实施方法,着重介绍其防喘振保护及电机过载保护等方面的自动安全控制,以确保机组安全、可靠运行。     

Hydrophilic/underwater superoleophobic graphene oxide membrane intercalated by TiO2 nanotubes for oil/water separation

GO/TiO₂ membrane was prepared by assembling GO nanosheets and TiO₂ nanotubes. The intercalation of TiO₂ nanotubes enlarged the space of GO interlayers and modified the surface morphology. Hydrophilic/underwater superoleophobic property of GO/TiO₂ membrane was obtained. Water permeability, hydrophilicity, oleophobicity and antifouling ability of GO-based membrane were all enhanced by intercalating TiO₂ nontubes. Membrane technology for oil/water separation has received increasing attention in recent years. In this study, the hydrophilic/underwater superoleophobic membrane with enhanced water permeability and antifouling ability were fabricated by synergistically assembling graphene oxide(GO) nanosheets and titanium dioxide (TiO₂) nanotubes for oil/water separation. GO/TiO₂ membrane exhibits hydrophilic and underwater superoleophobic properties with water contact angle of 62° and under water oil contact angle of 162.8°. GO/TiO₂ membrane shows greater water permeability with the water flux up to 531 L/(m²·h·bar), which was more than 5 times that of the pristine GO membrane. Moreover, GO/TiO₂membrane had excellent oil/water separation efficiency and anti-oil-fouling capability, as oil residual in filtrate after separation was below 5 mg/L and flux recovery ratios were over 80%.The results indicate that the intercalation of TiO₂ nanotubes into adjacent GO nanosheets enlarged the channel structure and modified surface topography of the obtained GO/TiO₂ membranes, which improved the hydrophilicity, permeability and anti-oil-fouling ability of the membranes, enlightening the great prospects of GO/TiO₂ membrane in oil-water treatment.     

火场残留助燃剂的提取分离及气相色谱/质谱分析

本文总结了从火灾现场提取样品中分离残留助燃剂的常用方法,比较了各种不同分离方法的优缺点及主要适用对象,并介绍了常见助燃剂的典型气相色谱/质谱图特性,为火灾调查识别的研究提供理论指导。     

Source separation recycling schemes: A survey

Municipal waste arisings continued to increase during the 1970s in all the industrialized economies. Currently, in the midst of a severe international economic recession, the continuing escalation in the costs of waste disposal poses significant problems for municipal authorities. With the data constraints firmly in mind, this paper estimates the secondary materials supply potential of the municipal waste stream. The calculations suggest that a significant supply potential remains to be utilized despite ‘respectable’ overall recycling rates in most industrial economies. Resource recovery options can be divided into ‘low technology’ source separation schemes and ‘high technology’ mechanical separation schemes. The authors concentrate on the former option and appraise (on the basis of social cost-benefit analysis) a number of schemes that have operated in both Europe and North America.     

AVERAGE DISCHARGE,PERENNIAL FLOW INITIATION,AND CHANNEL INITIATION ‐ SMALL SOUTHERN APPALACHIAN BASINS1

ABSTRACT: Regional average evapotranspiration estimates developed by water balance techniques are frequently used to estimate average discharge in ungaged streams. However, the lower stream size range for the validity of these techniques has not been explored. Flow records were collected and evaluated for 16 small streams in the Southern Appalachians to test whether the relationship between average discharge and drainage area in streams draining less than 200 acres was consistent with that of larger basins in the size range (> 10 square miles) typically gaged by the U.S. Geological Survey (USGS). This study was designed to evaluate predictors of average discharge in small ungaged streams for regulatory purposes, since many stream regulations, as well as recommendations for best management practices, are based on measures of stream size, including average discharge. The average discharge/drainage area relationship determined from gages on large streams held true down to the perennial flow initiation point. For the southern Appalachians, basin size corresponding to perennial flow is approximately 19 acres, ranging from 11 to 32 acres. There was a strong linear relationship (R²= 0.85) between average discharge and drainage area for all streams draining between 16 and 200 acres, and the average discharge for these streams was consistent with that predicted by the USGS Unit Area Runoff Map for Georgia. Drainage area was deemed an accurate predictor of average discharge, even in very small streams. Channel morphological features, such as active channel width, cross‐sectional area, and bankfull flow predicted from Manning's equation, were not accurate predictors of average discharge. Monthly baseflow statistics also were poor predictors of average discharge.     

水力旋流沉淀器在精对苯二甲酸废水处理中的应用

阐述了新型SXD水力旋流沉淀器的工作原理及结构特点，并从理论和实际应用两方面分析了影响水力旋流器处理效果的因素，评价了其在精对苯二甲酸废水处理中的性能。