The Information Content of a Scalar Plume – A Plume Tracing Perspective

The ability of many animals and insects to track a plume to its source is a particularly impressive feat when the fluid dynamics is considered. Inspired by this observation this research seeks to identify the information in a passive scalar plume suitable for developing robust and efficient plume tracing algorithms. The subject of this study is a scalar plume emanating from a point source in a turbulent boundary layer which has been modeled in a laboratory facility built specifically for this purpose. A coupled PIV-LIF technique is used to measure the velocity and scalar field in a time resolved fashion. This data set is analyzed and the convergence rates of five single-point statistics, suitable as kernels of plume tracing algorithms, are investigated. The experimental data shows that the scalar fluctuations over long downstream distances from the source are characterized by filamentary structures that lead to relatively slow convergence rates for any statistic that is based on mean concentrations. The scalar intermittency, however, converges rapidly toward its true value, in fact converging to a testable hypothesis for source location direction faster than the time scale of the larger scale plume meander.     

排污单位自行监测检查中发现的典型问题及改进建议

排污单位自行监测的质量管理,是环境管理部门关注的重点。针对排污单位自行监测工作中存在的质控措施不规范;监测结果公开不完整;样品交接记录、原始采样记录、样品分析原始记录不齐全;流量计未检定或过期等问题。从自行监测方案的制定、自行监测信息公开、企业手工监测、企业自动监测等4个方面提出:应实施具体的质控措施;将污染物排放方式及排放去向、未开展自行监测的原因等方面的内容全部公开;通过计量认证第三方环境监测机构制订相关的记录单;将流量计送至计量单位实验室检定或者请计量单位现场检定等建议,对今后促进排污单位提高自行监测工作水平有指导意义。     

论水污染物排放统计指标体系

水污染物排放统计指标体系包括水污染物排放统计指标以及排放管理指标,统计对象主要是规模以上点源。实施统计的污染源的规模应当是全国统一的。统计指标区分为指标、主要参数和辅助参数,既便于理解也便于管理;将排放指标细化为污染源排放量、入河排放量和通量使得排放概念更加清晰,有利于水环境管理。对入河排放量和污染源排放量的比较,可以确定纳入统计范围的污染源的代表性,对通量和入河排放量的比较可以推断非点源污染物排放状况。以流域为单元的,以通量、入河排放量和污染源排放量为主要概念的排放统计管理方式,有助于提高流域水污染防治的确定性和一致性。     

杭嘉湖地区淡水水产养殖污染物排放总量的研究

对杭嘉湖地区各种养殖模式选择有代表性的养殖品种,在养殖周期内分不同养殖阶段对其养殖水域进行CODCr、氨氮、总磷等有机污染物浓度测试,结合养殖池塘的产量、排水量等基本情况确定杭嘉湖地区水产养殖污染物排放系数。根据排放系数和区域水产养殖产量,计算得出杭嘉湖地区淡水水产养殖CODCr、氨氮、总磷等污染物的排放量。     

Rapid measurement of indoor mass-transfer coefficients

Indoor air pollutant concentrations can be influenced by how rapidly species are transported to and from surfaces. Consequently, a greater understanding of indoor transport phenomena to surfaces improves estimates of human exposure to indoor air pollutants. Here, we introduce two methods of rapidly and directly measuring species fluxes at indoor surfaces, allowing us to evaluate the transport-limited deposition velocity, v_t (a mass-transfer coefficient). The deposition velocity sensor (DeVS) method employs a small microbalance coated with a pure hydrocarbon, preferably octadecane. We quantify flux (or evaporation rate) of the hydrocarbon into a room by observing the rate of mass loss on the microbalance. The transport-limited deposition velocity, v_t,octadecane, is then obtained by combining the flux with the vapor pressure of the hydrocarbon. Simultaneously, v_t,ozone is quantified using the deposition velocity of ozone (DeVO) method, which acts as a standard to calibrate and evaluate DeVS. Specifically, DeVO evaluates ozone transport to surfaces by quantifying the conversion by ozone of nitrite to nitrate on a glass fiber filter. Simultaneous laboratory chamber experiments demonstrates that v_t for octadecane and ozone are strongly correlated, with the values for ozone 1.5 times greater than that for octadecane. In an office experiments, the DeVS method responds within minutes to step changes in conditions such as occupancy, activities and ventilation. At present, the results are in order-of-magnitude agreement with predicted indoor mass-transfer coefficients.     

环境监测在污染物总量控制中的作用

通过对湖北化肥厂生产装置全面达标，环保考核项目的各种监测分析，全面阐述了环境监测在污染物总量控制中的重要作用。     

抓好环保基础工作 创“清洁生产工厂”

通过创建“清洁生产工厂”活动化肥厂的环保工作上了一个新台阶，工业污染源得到治理，污染物排放总量大大降低，同时促进了资源综合复，提高了经济和环保效益。     

制服CO2排放的新探索

介绍了全球ＣＯ２排放的概况，反映了世界各国对温室效应所致的全球性气温上升极为关注，在这样的背景下，科学家对ＣＯ２排放的收集方法，包括生物吸收和化工利用等方法，做了许多有效的探索和试验，有的已接近工业实验阶段，如挪威石油界的见解，能源界对ＣＯ２排放更为关注，正在对各种矿物发电方式，结合环保意识，进行深入的方案性比较，并提出初步倾向性的意见，如荷兰科研界的见解。     

藻类抗毒性效应研究现状

污染物的毒性大小决定其在环境中的安全浓度，大力开展各类污染物对藻类毒性的研究，了解各种污染物在生态系统的迁移、转化及整体生态效应以及其生态风险评价无疑具有重要的理论意义和应用价值。本文综述了近年来我国在有机污染物对单种藻类和藻类群落的毒性效应的研究成果。     

上海市全面实行排污许可证交易的可行性探讨

排污许可证交易系统应建立在一个完善和有效的排污许可证管理体制基础上。文章认为上海市现有排污许可证体制的经济内涵、产权、初始分配方式、基价体系等方面必须进行改革和完善。与发达国家实行的排污许可证体制相比，上海市实行的排污许可证体制缺乏相应的经济内涵，只是排污许可“执照”体制，上海市的排污许可证交易实际上是排污许可“执照”交易。根据上海市现行排污许可证体制的经济内涵及实施现状来看，近期内全面推行真正意义上的排污许可证交易所必需的条件还未成熟。目前应当继续在黄浦江上游地区进行排污许可证交易，并在各方面进行探索，进一步积累经验。