曝气对潜流人工湿地污染物沿程降解规律的影响

通过构建曝气及未曝气潜流人工湿地小试实验系统,研究曝气对人工湿地床体中污染物沿程变化规律的影响。实验结果表明,曝气对污染物沿程降解规律的影响与污染物种类有关,在净化COD和氨氮时,曝气人工湿地污染物主要以水平推流式降解为主,未曝气系统床体中则出现分层现象,深度为40 cm以上的床体区域中污染物以水平推流式降解为主,40 cm以下区域则以垂直梯度降解方式为主。对于磷来说,两对比系统均以水平推流降解方式为主,但不同深度上的降解速率有所差异,曝气系统30~50 cm的床体中间层降解速率较快,而未曝气系统50 cm以下的床体底层降解速率较快。将对比系统总体净化效果进一步比较发现,对于COD的去除来说,温度的影响大些,而对于氨氮和TP的去除来说,曝气的影响则更为显著。     

曝气对水平潜流人工湿地水力特性的影响

通过构建曝气及未曝气潜流人工湿地小试实验系统,以NaCl为示踪剂开展示踪实验,研究曝气对人工湿地水力特性的影响。实验结果表明,两对比系统均存在不同程度的短流及死区现象,短流主要发生在床体表层,而死区则存在于床体底层。其中未曝气人工湿地系统的流场分布不均匀现象较为严重,示踪剂滞留在床体底层难以回收,系统水力效率较低(0.56)。比较而言,由于气流对水体的扰动作用,曝气对人工湿地系统水力效率有明显改善作用,减缓了床体表层水流速度,提高了示踪剂回收率,缩小了死区的范围,曝气人工湿地系统的水力效率为0.75。     

机械活化对CRT锥玻璃浸出动力学的影响

通过研究CRT锥玻璃经机械活化后在硝酸溶液体系中浸出反应动力学规律,考察了机械球磨转速、浸出温度以及硝酸初始浓度对锥玻璃中铅的浸出效果影响。研究结果表明,锥玻璃经机械活化预处理后,反应活性显著增强,锥玻璃中铅浸出率大幅度提高。浸出反应的表观活化能和反应级数由109.4 kJ/mol和0.79降至54.3 kJ/mol和0.51。     

转轮式洗轮机对车轮带泥的冲洗效果简

施工车辆车轮带泥是我国道路扬尘污染控制面临的共性和突出问题。为在国内推广使用洗轮机提供技术依据,通过检测工地出口外道路积尘负荷来估算转轮式洗轮机对车轮带泥的冲洗效率,并以该洗轮机作为车轮带泥检测设备,检测和统计北京市车轮带泥量。结果表明,（1）转轮式洗轮机可以将工地出口外100 m道路积尘负荷增量由64.4 g/m²降至5.9 g/m²,转轮式洗轮机对车轮带泥的冲洗效率大于90%;（2）渣土车和混凝土车车轮带泥量的平均值分别为5.1和2.2 kg/车;（3）北京市未来车轮带泥量将超过8.8万t/a,施工车辆全部经过转轮式洗轮机冲洗后,车轮带泥量可削减7.9万t/a。建议在相关法律法规中以强制性条款落实施工车辆车轮带泥机械化冲洗要求。     

医疗垃圾管理与处置方法研究

医疗垃圾是一类成分复杂并有特殊危害的废物，按照“从摇蓝到坟墓”的理论，分析探讨医疗垃圾产生、运输和处置各环节的管理方法和处理对策，并介绍焚烧法、高压消毒法等６种处理方法。     

高浓度O_3水研究

介绍了臭氧水溶液研究的进展及其广泛诱人的应用前景 ,同时阐叙了产生高浓度臭氧、高效率溶解臭氧及制取臭氧水溶液等方法。利用这些方法 ,臭氧水溶液的臭氧浓度达 8g/m3,臭氧溶解率达 98%以上     

Acidic and basic properties and buffer capacity of airborne particulate matter in an urban area of Beijing

Particles with aerodynamic diameters <10  $\upmu $ m (PM₁₀) and particles with aerodynamic diameters <2.5  $\upmu $ m (PM_2.5) were sampled during summer 2006 in Beijing and mass concentrations, water-soluble ionic compounds concentrations, and acidic buffer capacity were analyzed. Results show that the mass concentration ranges of PM₁₀ and PM_2.5 were from 56.4 to 226.6  $\upmu $ g/m³ and from 31.3 to 200.7  $\upmu $ g/m³ during sampling days, respectively. Concentrations of F^???, Cl^???, NO $_{3}^{\,\,-}$ , NO $_{2}^{\,\,-}$ , SO $_{4}^{\,\,2-}$ , Ac^???, Ca^2?+?, Na^?+?, K^?+?, Mg^2?+?, and NH $_{4}^{\,\,+}$ in particles were analyzed by ion chromatography. Microtitration was adapted to determine the acidic?Cbasic property and the change of the buffering systems in different pH of the aqueous solution in which the PM is suspended. The major alkalinity and buffer capacity of particles were analyzed and calculated. The average carbonate buffer capacity was 0.3 mmol/g in PM_2.5 and 0.7 mmol/g in PM₁₀. The average acetic acid buffer capacity was 0.1 mmol/g in PM_2.5 and 0.3 mmol/g in PM₁₀. Carbonate and acetic acid are the main species for the buffer capacity in the particle phase. The average mass of carbonate was 71.0 mg/g in PM₁₀ and 46.7 mg/g in PM_2.5. The average mass of acetic acid was 11.2 mg/g in PM_2.5 and 20.0 mg/g in PM₁₀.     

松花江依兰江段地表水监测断面污染状况分析

在连续三年监测数据基础上,用单项污染指数,综合污染指数和污染负荷分担率及历史数据均值偏差估算等方法,对五个监测断面的污染状况进行评价,得出科学的评价结论.     

大气中碳氢化合物来源的分析研究

1989年秋至1990年春夏季,对北京城郊大气进行了非甲烷总烃(NMHC)及C2—C11分类测定。测点以交通路口为主,对汽车尾气排放情况作了重点研究,观测了典型路口西单安全岛空气中NMHC等浓度日变化;分析了这些路口空气中总烷烃(甲烷除外)与总烯烃等比值(Alkane/Alkene),并与某些固定源及郊区清洁点的比值进行了比较。一般而言,北京环境大气中Alkane约占NHHC60％,与世界主要大城市相当;Alkene约占21％,略高;总芳香烃(Alkyne)约占19％,比上述城市都低。      

Assessment for Salinized Wasteland Expansion and Land Use Change Using GIS and Remote Sensing in the West Part of Northeast China

Due to human impact under climatic variations, western part of Northeast China has suffered substantial land degradation during past decades. This paper presents an integrated study of expansion process of salinized wasteland in Da’an County, a typical salt-affected area in Northeast China, by using Geographic Information Systems (GIS) and remote sensing. The study explores the temporal and spatial characteristics of salinized wasteland expansion from 1954 to 2004, and land use/cover changes during this period. During the past 50 years, the salinized wasteland in study area have increased by 135,995 ha, and in 2004 covers 32.31% of the total area, in the meantime grassland has decreased by 104,697 ha and in 2004 covers only 13.15% of the study area. Grasslands, croplands and swamplands were found the three main land use types converted into salinized wasteland. Land use/cover changes shows that between 1954 and 2004, 48.6% of grasslands, 42.5% of swamplands, and 14.1% of croplands were transformed into salinized wasteland, respectively. Lastly, the major factors influencing salinized wasteland expansion and land use/cover changes were also explored. In general, climatic factors supplied a potential environment for soil salinization. Human-related factors, such as policy, population, overgrazing, and intensified and unreasonable utilization of land and water resources are the main causes of salinized wasteland expansion.