间歇曝气SBR工艺脱氮除磷试验研究

采用间歇曝气序批式反应器(SBR)工艺,通过曝气时间、交替次数的调整对该系统的脱氮除磷效果进行了研究,最终将工艺确定为厌氧1.5 h、好氧1.0 h、缺氧1.0 h、好氧20 min、缺氧1.0 h、好氧20 min.同时进行批式试验,对不同阶段的反硝化除磷菌(DPAOs)占除磷菌(PAOs)的比例进行了计算.结果表明:该系统与最初的厌氧/好氧SBR相比节省了44%的曝气量,且对COD、总氮、氨氮和磷的去除率分别达88%、89%、100%和100%,系统中DPAOs所占比例为39%.     

新型非焚烧医疗废物处置技术:脉动高压蒸汽灭菌-破碎

本文介绍了高压蒸汽灭菌结合破碎的医疗废物处置技术的原理、技术特点以及处置过程中排放的废气废水的处理方法。从节能环保和经济可靠的角度，对高压蒸汽灭菌处置技术与焚烧技术进行了比较，结果表明高压蒸汽灭菌-破碎的医疗废物处置技术可以避免传统焚烧技术由于设计、操作等问题所引起的二噁[口英]二次污染等问题，无论是设备本身还是运行维护费用均要低于焚烧技术：其更加适合我国相对小规模的医疗废物的处理。     

扎龙湿地水环境质量分析与净化率研究

扎龙湿地是我国第一个以鹤类等大型水禽为主体的湿地生态型国家级自然保护区.它具有宝贵的动植物资源,对生态环境起着重要的调节作用.本文以扎龙湿地水环境为切入点,通过实测数据分析了扎龙湿地的水质状况并对影响因素进行了分析,同时对扎龙湿地的净化水质功能进行了研究.这对于改善湿地水环境,更好地维持湿地生物多样性,维护流域的生态安全和生产生活活动都具有重要意义.     

Molecular characterization of root exudates using Fourier transform ion cyclotron resonance mass spectrometry

The release of root exudates (REs) provides an important source of soil organic carbon. This work revealed the molecular composition of REs of different plant species including alfalfa (Medicago sativa L.), bean (Phaseolus vulgaris L.), barley (Hordeum vulgare L.), maize (Zea mays), wheat (Triticum aestivum L.), ryegrass (Lolium perenne L.) and pumpkin (Cucurbita maxima) using electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). The combination of positive ion mode (+ESI) and negative ion mode (-ESI) increased the number of the molecules detected by ESI FT-ICR MS, and a total of 8758 molecules were identified across all the samples. In detail, lipids and proteins and unsaturated hydrocarbons were more easily detected in +ESI mode, while aromatic compounds with high O/C were readily ionized in -ESI mode, and only 38% of the total assigned formulas were shared by -ESI and +ESI modes. Multivariate statistical analysis of the formulas indicated that the close related plants species secreted REs with similar molecular components. Moreover, the unsaturation degree and nitrogen content were the two key parameters able to distinguish the similarities and differences of molecular components of REs between plant species. The results provided a feasible analysis method for characterization of the molecular components of REs and for the first time characterized the molecular components of REs of a variety of plant species using ESI FT-ICR MS.     

医疗药品污染物减排项目成本控制策略研究

通过成本控制方法对医疗药品污染物减排,提出基于Hausman检验方法的医疗药品污染物减排项目成本控制模型,促进的医疗药品污染物减排项目转型升级的同时降低成本开销,提高环境污染治理水平。构建医疗药品污染物减排项目成本控制的约束参量模型,采用自适应均衡博弈控制方法进行成本控制数学建模,结合描述性统计量分析方法进行医疗药品污染物减排项目成本控制的统计分析和稳健性检验,采用Hausman检验方法实现成本控制优化,促进污染物减排项目的转型优化升级。     

Managed grassland alters soil N dynamics and N2O emissions in temperate steppe

Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen(N) dynamics and nitrous oxide(N_2O) emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N_2O emissions by field experiments in Hulunber in northern China. Soil(0–10 cm), nitrate(NO_3~-),ammonium(NH_4~+), and microbial N were measured in plots in a temperate steppe(Leymus chinensis grassland) and two managed grasslands(Medicago sativa and Bromus inermis grasslands) in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO_3~–-N, but did not change NH_4~–N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa(i.e., a legume grass) increased N_2O emissions by 26.2%, while the conversion to the B. inermis(i.e., a non-legume grass) reduced N_2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO?3~-+–N and NH_4~–N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N_2O emissions.     

Characterization of aircraft emissions and air quality impacts of an international airport

Beijing Capital International Airport(ZBAA) is the world's second busiest airport. In this study, the emissions of air pollutants from aircraft and other sources at ZBAA in 2015 were estimated using an improved method, which considered the mixing layer height calculated based on aircraft meteorological data relay(AMDAR), instead of using the height(915 m)recommended by ICAO. The yearly emissions of NO_x, CO, VOCs, SO_2, and PM_(2.5) at the airport were 8.76 × 10~3, 4.43 × 10~3, 5.43 × 10~2, 4.80 × 10~2, and 1.49 × 10~2 ton/year, respectively. The spatial–temporal distribution of aircraft emissions was systematically analyzed to understand the emission characteristics of aircraft. The results indicated that NOxwas mainly emitted during the take-off and climb phases, accounting for 20.5% and 55.5% of the total emissions. CO and HC were mainly emitted during the taxi phase, accounting for 91.6%and 92.2% of the total emissions. Because the mixing layer height was high in summer, the emissions of aircraft were at the highest level throughout the year. Based on the detailed emissions inventory, four seasons simulation using WRF-CMAQ model was performed over the domain surrounding the airport. The results indicated that the contribution to PM_(2.5) was relatively high in winter; the average impact was about 1.15 μg/m~3 within a radius of1 km around the airport. Meanwhile, the near surroundings and southwest areas of the airport are the most sensitive to PM_(2.5).     

某炼铁厂炉顶除尘系统的风量调整与仿真分析研究

某炼铁厂炉顶除尘设备运行中各吸尘点风量失衡,造成除尘系统不能发挥应有的作用.通过对除尘系统各吸尘点风量及阻力、除尘器性能、风机性能等参数进行测试,并利用Fluent对系统内流场分布进行仿真与评估、对系统阻力平衡点进行分析,重新调整各个调节阀的开度,优化系统各吸尘点风量分布.调整后,不仅使系统达到现有条件下最佳除尘效果,而且找出了除尘系统设计及运行缺陷,提出了可行的解决方案.     

活性炭吸附二硫化碳解析气相色谱法测定废气中乙酸乙酯和乙酸丁酯研究

采用活性炭管吸附废气中的乙酸乙酯和乙酸丁酯,经二硫化碳萃取解析,使用DM-1色谱柱分离后FID检测.实验结果表明:(1)采用活性炭管吸附废气中的目标组份,富集效率良好,二硫化碳解析率可达92％以上;(2)当乙酸乙酯和乙酸丁酯的含量为6.8～102 ng时,测定结果的相对标准偏差分别在1.8％ ～4.2％和3.2％ ～6.1％之间(n=6);(3)当样品采集量为30 L时,方法检出限分别为0.02 mg·m-3和0.02 mg·m-3.因此,方法能满足实验对空气废气中的乙酸乙酯和乙酸丁酯的检测要求.     

烟台市环境空气自动监测中PM10与PM2.5数据异常情况分析研究

根据2014年烟台市范围内全部环境空气自动监测点位的PM 10和PM2.5数据,分析了不同监测仪器组合下PM10和PM2.5的倒挂情况,选取了倒挂率较高的4种监测仪器组合,将监测数据分为不同季节和时段比较分析,结果表明:大气湿度较高的季节倒挂率高于其他季节,夜间倒挂率高于昼间,雾霾等重污染天气时高于其他时段.数据采集频率、监测方法、监测仪器、采样管加热方式不同以及测量误差等都是产生倒挂现象的因素.