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861.
污染物总量控制制度是我国环境保护制度的重要组成部分。结合污染物总量控制制度的实施现状,分析实施过程中减排基数、核算体系、责任主体等方面存在的问题。提出,改革现行污染物总量控制制度,将总量控制与改革中的排污许可制相融合,落实企业主体责任,将总量指标与环境质量改善挂钩,建立差异化的减排核算体系,并加强日常监管,达到改善环境质量的目标。 相似文献
862.
介绍了燃煤电厂超低排放气态污染物监测系统的采样系统和分析单元,分析了其各自的优缺点。对稀释抽取式、冷干抽取式和热湿抽取式3种采样方法,以及非分散红外吸收法(NDIR)、非分散紫外吸收法(NDUV)、紫外差分吸收法(DOAS)、紫外荧光法(UVF)和化学发光法(CL)5种分析方法进行对比。结果表明,冷干抽取式+紫外差分法以及稀释抽取式+紫外荧光法+化学发光法可以较好地符合燃煤电厂超低排放监测的要求。 相似文献
863.
TiO2在碳纳米管上的复合材料可以增加材料的光催化性能,已成为新的研究热点.本文采用低温液相法成功地合成了TiO2/CNTs复合材料,并用TEM、XRD和UV-vis对材料进行了表征,结果表明,TiO2很好地分散在CNTs上,具有显著的催化效果,有很好的应用前景. 相似文献
864.
Spectroscopic Distribution of Dissolved Organic Matter in a Dam Reservoir Impacted by Turbid Storm Runoff 总被引:1,自引:0,他引:1
Spectroscopic characteristics of dissolved organic matter (DOM) in a large dam reservoir were determined using ultraviolet
absorbance and fluorescence spectroscopy to investigate spatial distribution of DOM composition after turbid storm runoff.
Water samples were collected along a longitudinal axis of the reservoir at three to four depths after a severe storm runoff.
Vertical profiles of turbidity data showed that a turbid water layer was located at a middle depth of the entire reservoir.
The spectroscopic characteristics of DOM samples in the turbid water layer were similar to those of terrestrial DOM, as demonstrated
by the higher specific UV absorbance (SUVA) and the lower fluorescence emission intensity ratio (F
450/F
500) compared to other surrounding DOM samples in the reservoir. Synchronous fluorescence spectroscopy revealed that higher content
of humic-like DOM composition was contained in the turbid water. Fluorescence excitation–emission matrix (EEM) showed that
lower content of protein-like aromatic amino acids was present in the turbid water DOM. The highest protein-like fluorescence
was typically observed at a bottom layer of each sampling location. The bottom water DOM exhibited extremely high protein-like
florescence near the dam site. The particular observation was attributed to the low water temperature and the isolation of
the local bottom water due to the upper location of the withdrawal outlet near the dam. Our results suggest that the distribution
of DOM composition in a dam reservoir is strongly influenced by the outflow operation, such as selective withdrawal, as well
as terrestrial-origin DOM inputs from storm runoff. 相似文献
865.
调查分析蔷薇河非点源废水排放情况,结合相关统计资料,核算出蔷薇河非点源废水污染物的排放量。结论表明,农田回归水污染是蔷薇河水体非点源污染的主要因素。 相似文献
866.
867.
上海浦东国际机场飞机尾气排放对机场附近空气质量的影响 总被引:1,自引:0,他引:1
统计2012年10月和11月浦东机场飞机机型和航班架次,根据各类飞机起降的污染物排放设计工作参数,估算出2012年浦东机场飞机起降时排放的NO2、SO2、CO和HC的估算值。利用浦东新区13个空气监测子站二氧化氮和二氧化硫数据绘制等值线图。结果显示,机场所在的江镇点位和祝桥点位二氧化氮浓度变化受飞机影响很大,而飞机排放的二氧化硫对两个点位的影响可以忽略不计。建议采用改进飞机滑行路线、探讨征收飞机碳排放税等措施减少飞机尾气排放对空气质量的影响。 相似文献
868.
The contribution of Korean forests to carbon sequestration for anthropogenic carbon emissions was evaluated. In addition,
monitoring of carbon species released from forest fires was conducted. Despite a high carbon uptake by Korean forests, a tremendous
increase in fossil fuel burning resulted in a small contribution by forests to carbon removal. The removal efficiency had
a 5–31% range with an average of 12% during the period 1973–2002. In 2000, the amount of carbon released from burned trees
corresponded to 1.6% of carbon uptake by forests. The distribution of surface CO concentration (ppb) derived from MOPITT (Measurement
of Pollution in the Troposphere) showed high CO levels over the East/Japan Sea on April 10, 2000 when the largest forest fires
occurred along the east coast of Korea. Trajectory analysis and ground CO measurements also indicated that CO levels over
the East/Japan Sea were influenced by forest fires. This study suggests that continuous monitoring of carbon emissions from
forest fires is needed for a more reliable estimate of carbon flux in the environment. 相似文献
869.
Krzysztof Brzozowski 《Environmental Modeling and Assessment》2006,11(4):371-380
The paper presents a new method of air pollution modelling on a micro scale. For estimation of concentration of car exhaust pollutants, each car is treated as an instantaneous moving emission source. This approach enables us to model time and spatial changes of emission, especially during cold and cool start of an engine. These stages of engine work are a source of significant pollution concentration in urban areas. In this work, two models are proposed: one for the estimation of emission after cold start of the engine and another for the prediction of pollutant concentration. The first model (defined for individual exhaust gas pollutants) enables us to calculate the emission as a function of time after the cold or cool start, ambient temperature and average speed of motion. This model uses the HBEFA database. The second mathematical model is developed in order to calculate the pollutant dispersion and concentrations. The finite volume method is applied to discretise the set of partial differential equations describing wind flow and pollutant dispersion in the domain considered. Models presented in this paper can be called short-term models on a small spatial scale. The results of numerical simulation of pollutant emission and dispersion are also presented. 相似文献
870.
为验证二氧化碳排放量的测试技术适用性及可行性,获取燃煤电厂机组碳排放特征,系统比较不同测试方法之间碳排放量的差异,对某典型火电机组二氧化碳排放开展测试,结果表明,不同测试原理及设备二氧化碳排放实测体积分数均较为接近。测试机组CO2实测体积分数为11.28%~14.21%,与负荷变化呈一定的正相关关系,不同负荷下基准氧含量(体积分数6%)基本无变化。测试机组排放量与负荷正相关,使用了缺省值的指南排放量最高,与其他方法排放量相对偏差均值为31.6%;使用入炉煤实测数据的指南排放量差异不大,相对偏差为0.1%;使用入炉煤实测数据的2版指南排放量高于直接测量法,相对偏差均值为4.9%;直接测量各类方法间相对偏差均值为1.0%,其中在线法与手工法间相对偏差均值为1.2%。CO2排放强度与负荷负相关,实验条件下,机组负荷越高,碳排放强度越低。 相似文献