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51.
对江苏省环境空气质量自动监测的数采平台现状进行了分析,并就省控中心统一软件采集中心站数据平台,省控中心统一软件采集子站数据平台,以及省控中心统一子站数采软、硬件平台方案进行了比较,指出为实现对全省各子站数据的有效质量管理,省环境空气质量自动监测平台的集成必须实现从子站直接采集原始分析数据,而要实现真正意义上的空气监测子站广域网连接,应由目前的省控中心统一软件采集子站数据的平台向省控制中心统一子站数采软、硬件平台过渡。  相似文献   
52.
应用环境噪声主观反应调查和现场实地测试调查的统计结果,根据心理学确定阈值的原则,提出我国风景旅游区两种区域类型的环境噪声标准的建议,并对标准的可行性和代表性进行了分析和讨论.  相似文献   
53.
本文通过对和平区近几年环境空气监测数据的分析,评价了和平区“八·五”期间的环境空气质量状况及变化趋势。  相似文献   
54.
用离子色谱法测定环境空气中低浓度氯化氢,是通过测定氯离子质量浓度间接测定氯化氢的质量浓度,测定过程极易受外来氯离子的干扰,使空白值偏高。通过试验确定测定过程中可能存在氯离子干扰的环节,并采取一系列方法消除前期准备、采样和分析全过程中的干扰,以降低空白值。  相似文献   
55.
简述了原有广州市环境空气自动监测网络情况,通过对环境空气自动监测网络的集成优化,增设站点、扩展监测项目和引入新技术,建立了一个"金字塔形"的集天地空一体化的环境空气监测网络,弥补了原有监测网络在反映环境空气质量总体水平、污染来源解析、预报预警所需的环境质量信息、对环境空气质量的评估等方面的不足,该网络已成功应用于广州亚运会的空气质量保障。  相似文献   
56.
In this study, ammonia emissions characteristics of typical light-duty gasoline vehicles were obtained through laboratory vehicle bench test and combined with New European Driving Cycle (NEDC) condition and Worldwide Harmonized Light Vehicles Test Cycle (WLTC) condition. The influence of ambient temperature on ammonia emissions is mainly concentrated in the cold start stage. The influence of ambient temperature on ammonia emission is shown that the ammonia emissions of light-duty gasoline vehicles under ambient temperature conditions (14 and 23°C) are lower than those under low ambient temperature conditions (?7°C) and high ambient temperature conditions (35 and 40°C). The influence of TWC on ammonia emission is shown that ammonia is a by-product of the catalytic reduction reaction of conventional gas pollutants in the exhaust gas in the TWC. Under NEDC operating conditions and WLTC operating conditions, ammonia emissions after the catalyst are 45 times and 72 times that before the catalyst, respectively. In terms of ammonia emissions control strategy research, Pd/Rh combination can reduce NH3 formation more effectively than catalyst with a single Pd formula. Precise control of the engine's air-fuel ratio and combination with the optimized matched precious metal ratio TWC can effectively reduce ammonia emissions.  相似文献   
57.
The concentration of short-chain polychlorinated paraffins(SCCPs) in the urban air of Dalian,China was monitored from September 2016 to August 2017 with a self-developed passive sampler(PAS1) and an active high-volume sampler, simultaneously. PAS1 successfully collected the entire target SCCPs in the ambient air. Air SCCPs sampled by PAS1 were found be in the linear uptake stage during 181 days of sampling. Passive and active samples showed comparable congener profiles, and the dominant contributors of SCCPs in the two kinds of samples were similar. A significant linear correlation was observed between the total concentration of SCCPs sampled by PAS1 and active sampler in the four seasons. The passive sampling rates of the PAS1 for the gas and particulate phases of SCCPs were measured. The quantitative structure–property relationship of the sampling rate of PAS1(Rair) for gas-phase SCCPs was studied. From the molecular point of view, Rairwas mainly affected by the molecular weight and sub-cooled liquid vapor pressure of SCCPs. In general, SCCPs in the urban air of Dalian mainly existed in gas phase,lower molecular weight SCCPs primarily occurred in the gas phase, whereas higher molecular weight SCCPs were predominately adsorbed or absorbed on airborne particles. The air concentration of SCCPs in the four seasons were different, the correlation of the concentration of SCCPs in the air with the meteorology parameters was conducted. The exposure risk by intake air SCCPs of the residents around the sampling sites was evaluated according to the European risk assessment standards.  相似文献   
58.
The total concentrations and component profiles of polycyclic aromatic hydrocarbons (PAHs) in ambient air, surface soil and wheat grain collected from wheat fields near a large steel-smelting manufacturer in Northern China were determined. Based on the specific isomeric ratios of paired species in ambient air, principle component analysis and multivariate linear regression, the main emission source of local PAHs was identified as a mixture of industrial and domestic coal combustion, biomass burning and traffic exhaust. The total organic carbon (TOC) fraction was considerably correlated with the total and individual PAH concentrations in surface soil. The total concentrations of PAHs in wheat grain were relatively low, with dominant low molecular weight constituents, and the compositional profile was more similar to that in ambient air than in topsoil. Combined with more significant results from partial correlation and linear regression models, the contribution from air PAHs to grain PAHs may be greater than that from soil PAHs.  相似文献   
59.
利用2001年至2010年沈阳市大气自动监测数据进行分析得出:除夕夜间集中燃放大量烟花爆竹可造成空气污染,特别是人口集中的主城区尤为严重。其中可吸入颗粒物浓度升幅最大、污染最严重,最大浓度出现在凌晨1时到2时,主城区平均浓度达到0.625 mg/m3,超过国家二级日均值标准3.2倍;二氧化硫浓度升高明显,最大浓度出现零时到1时,一氧化碳浓度略有升高,二氧化氮浓度没有明显变化。  相似文献   
60.
我国南北方城市空气环境质量对比分析   总被引:2,自引:0,他引:2  
依据国家环境监测部门公布的空气环境质量日报,对27个省会城市、4个直辖市城市的2004年-2006年空气质量数据进行分析。结果显示:我国城市空气污染指数(API)时空差异明显,冬、春季节API值高于夏季和秋季,北方城市的API均值高于南方城市;PM10是大气环境的主要污染物,作为首要污染物出现所占比例南、北方城市分别是66.64%和83.97%;SO2为首要污染物所占比例南、北方城市分别是7.28%和6.19%;北方城市平均Ⅰ级和Ⅱ级天数所占百分比之和为77.00%,重污染级天数所占比例达到1.02%;南方城市平均Ⅰ级和Ⅱ级天数所占百分比之和为87.24%,重污染天数所占百分比是0.04%;城市空气质量优、良天数呈增加趋势。  相似文献   
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