Characterization of particle number concentrations and PM<Subscript>2.5</Subscript> in a school: influence of outdoor air pollution on indoor air

Background, Aim and Scope  

The impact of air pollution on school children’s health is currently one of the key foci of international and national agencies. Of particular concern are ultrafine particles which are emitted in large quantities, contain large concentrations of toxins and are deposited deeply in the respiratory tract.     

玉裂废水粘度对二氧化锰臭氧催化氧化处理特性的影响

通过FT-IR和GC—MS检测分析，表明了压裂废水中有机物主要以苯环结构为主的芳香类化合物和其他杂环化合物，苯环及杂环上的主要官能团包括酮、酯、羧酸、醛、酚、氨基等。同时，压裂废水中的粘度为常规水粘度的2～3倍。针对压裂废水高粘度和高COD污染水质特征，实验研究了压裂废水二氧化锰臭氧催化氧化处理特性以及粘度对处理效果的影响，研究结果表明，在粘度较高（2．2×10-3 Pa·s）压裂废水中，投加的化学药剂很难扩散，羟基自由基·OH的利用效率较低，处理效果较差。通过投加过硫酸钾（5g／L）降粘后，可在很大程度上提高二氧化锰臭氧催化氧化的处理效果。通过对压裂废水中有机物分子量分布、FT-IR分析以及GC—MS分析可知，二氧化锰臭氧催化氧化处理压裂废水是通过激发羟基自由基，破坏水中有机物极性和有机物化学构造，将复杂长链有机物转变为简单有机物，其出水COD可达到国家污水综合排放标准中的二级排放标准。     

关于推动青海省环境会计工作的若干思考

随着人口的剧增和社会需求的臌胀，环境问题日渐引起各国政府普遍关注。进入20世纪90年代，越来越多的西方国家把环境损益核算纳入会计研究的领域，逐步出现和形成了环境会计。环境会计制度也是近年来国内会计学界热议的话题。文章在把握我国环境会计概念的基础上，对环境会计在推动青海省环境保护的必要性进行了阐述，提出了建立环境会计促进青海省社会经济可持续发展的几点建议。     

Nitrous oxide emissions from an intensively managed greenhouse vegetable cropping system in Northern China

Nitrous oxide (N₂O) emissions from a typical greenhouse vegetable system in Northern China were measured from February 2004 to January 2006 using a close chamber method. Four nitrogen management levels (NN, MN, CN, and SN) were used. N₂O emissions occurred intermittently in the growing season, strongly correlating with N fertilization and irrigation. No peak emissions were observed after fertilization in the late Autumn season due to low soil temperature. 57-94% of the seasonal N₂O emissions came from the initial growth stage, corresponding to the rewetting process in the soil. The annual N₂O emissions ranged from 2.6 to 8.8 kg N ha⁻¹ yr⁻¹, accounting for 0.27-0.30% of the annual nitrogen input. Compared with conventional N management, site-specific N management reduced N fertilization rate by 69% in 2004 and by 76% in 2005, and consequently reduced N₂O emissions by 51% in 2004 and 27% in 2005, respectively.     

医疗废弃物焚烧挥发性氯含量与热值测试与估算

通过测定上海某医疗废弃物处置公司设定燃烧工况条件下某时间段内烟气中HC l的平均排放速率,估算出上海地区医疗垃圾废物中的可燃烧转化氯含量在2.33%~2.64%左右;通过测定各较小采样时间段(2 m in)的烟气HC l浓度测定发现批次进料造成烟气中HC l浓度近4倍的波动,通过初步的热平衡估算得到医疗废弃物的热值大致在21.8 M J/kg,得到的结果可为我国医疗废弃物的焚烧工艺设计提供基础依据。     

长沙市夏季大气颗粒物中重金属的形态及其源解析

对长沙市高开区、经开区、开福区以及马坡岭4个采样点夏季的大气颗粒物(TSP)浓度以及颗粒物中的重金属元素Cu、Zn、Mn、Pb和Cd的浓度和形态分布进行了研究分析,利用污染因子(Cf)对重金属元素的可保持能力进行了评价,并利用因子分析方法(PCA)分析TSP中重金属元素的主要来源。结果显示长沙市夏季TSP平均浓度为220.7μg/m3,表明长沙市颗粒物污染较严重。TSP中重金属元素浓度大小顺序为:ZnPbCuMnCd。从形态分布来看,大约63.3%~89.0%的Cu主要存在于可氧化态(F3),而Mn在这一态中分布最少。元素Zn、Cd则主要分布在弱酸提取态,分别占了70%和35%。Pb主要分布在残渣态,大约为24%~43%。由污染因子计算可知Cu、Cd和Zn比Mn、Pb有更高的迁移性。     

4种人工湿地填料对磷的吸附特性分析

采用等温吸附、吸附动力学、填料饱和吸附后磷素释放实验,研究了紫色土、河沙、页岩、石灰岩对磷的吸附特征,结果表明Langmuir和Freundlich等温吸附方程均能很好地拟合各填料对磷的吸附特征,各填料对磷的最大吸附量大小顺序依次为石灰岩(666.67 mg/kg)河沙(500.00 mg/kg)页岩(434.78 mg/kg)紫色土(416.67 mg/kg);从反应速率来看,吸附过程都可分为快、中、慢3个阶段;相对一级动力学方程、双常数方程而言,Elovich方程对4种填料的吸附动力学特征拟合最好,决定系数R~2在0.831～0.966之间;从磷的解吸率来看,各填料释磷大小顺序依次为河沙(4.257%)页岩(3.803%)石灰岩(3.638%)紫色土(2.134%)。综合考察得出,石灰岩更适合作为人工湿地污水除磷的填料。     

Flexible interval mixed-integer bi-infinite programming for environmental systems management under uncertainty

A number of inexact programming methods have been developed for municipal solid waste management under uncertainty. However, most of them do not allow the parameters in the objective and constraints of a programming problem to be functional intervals (i.e., the lower and upper bounds of the intervals are functions of impact factors). In this study, a flexible interval mixed-integer bi-infinite programming (FIMIBIP) method is developed in response to the above concern. A case study is also conducted; the solutions are then compared with those obtained from interval mixed-integer bi-infinite programming (IMIBIP) and fuzzy interval mixed-integer programming (FIMIP) methods. It is indicated that the solutions through FIMIBIP can provide decision support for cost-effectively diverting municipal solid waste, and for sizing, timing and siting the facilities’ expansion during the entire planning horizon. These schemes are more flexible than those identified through IMIBIP since the tolerance intervals are introduced to measure the level of constraints satisfaction. The FIMIBIP schemes may also be robust since the solutions are “globally-optimal” under all scenarios caused by the fluctuation of gas/energy prices, while the conventional ones are merely “locally-optimal” under a certain scenario.     

电除尘器伏安特性规律研究

对以480C型板为阳极板、不同阴极线类型、不同极距、不同极线距以及不同辅助电极配置的共计384组典型极配的伏安特性进行了全面系统的试验分析。提出了以I=aV^b幂函数的形式来数学表征常规极配的伏安特性曲线，并给出了对应极配的a、b值，对比结果表明,实测值与函数计算值的符合度均在99.5％以上。     

垃圾渗滤液处理工艺中有机污染物的三维荧光光谱

利用荧光发射和三维荧光光谱研究了三峡库区某垃圾堆场的渗滤液及其处理工艺出水溶解性有机质(DOM)的荧光光谱特性。堆场渗滤液的DOM含有类酪氨酸、色氨酸及紫外区类富里酸，特征荧光峰中心位于E_x/E_m=275 nm/305 nm，为高激发波长类酪氨酸，与前人的研究结果并不一致，这可能与垃圾的堆放期有关。渗滤液和各处理工艺出水的荧光指数f_450/500均大于1.9，表明腐殖质主要为微生物源。渗滤液在处理前后荧光峰特征和强度均发生明显改变，类蛋白荧光强度与DOC值变化趋势基本一致。生化处理工艺中，类蛋白荧光强度降低了66.4%～95.5%，紫外区类富里酸荧光强度只降低了28.8%，显示类蛋白质具有良好的可生化性，而类富里酸相对较难生化降解。三维荧光光谱能反映渗滤液处理过程中污染物的种类、性质和数量等变化信息，能快速地进行定性分析、定量评价。