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91.
易江 《干旱环境监测》1995,9(3):165-166,182
论述了我国燃煤固定污染源二氧化硫排放总量监测工作中存在的问题,开展了完成的研究课题,实测方法,研制的采样和测试仪器设备等有关大气环境监测管理中一些重要的实际问题。  相似文献   
92.
我国SO2排放总量控制方法探索与初步评估   总被引:10,自引:2,他引:10  
介绍了我国SO3排放总量的控制方法以及大气网络输送理论在总量控制研究中的应用,并对大气SO2总量控制方法的研究结果做了初步评估,给出了我国2010年SO2排放总量控制的目标(甘肃、新疆、青海和西藏的大部分地区除外)。  相似文献   
93.
论述了大气监测分析方法标准化研究的特点,内容,样品采集方法和保存条件,样品预处理方法和测定条件,干扰检验,方法的基本特征参数第一轮测定,实际样品的测定等问题。  相似文献   
94.
BP网络模型在朝阳地区大气污染预报中的应用   总被引:1,自引:0,他引:1  
厚春华 《环境保护科学》2007,33(5):53-54,67
目前,人工神经网络理论发展迅速,并在模式识别和系统辨识中得到广泛应用。而其中采用误差反向传播方法(Back Error Propagation)的BP网络模型是目前应用最为广泛的神经网络模型之一,它是一种简单而又非常有效的算法。本文应用人工神经网络方法,在模拟人脑的思维方式下,建立了大气污染物浓度的神经网络预报模型,并将计算结果与监测值进行了对比验证,计算结果表明,BP模型应用于大气污染物浓度预报具有较高的预报精度。  相似文献   
95.
Airborne particulate matter (PM) with an aerodynamic size cutoff of 10 µm (PM10) has been collected using a high volume air sampler at two locations (urban and residential) in the city of Ahvaz, Iran, for sixteen 24-hour periods over four months (late summer to early winter). Microplastics (MPs) in the PM were isolated after sample digestion and were subsequently characterised by established techniques. All MPs sampled (n = 322) were of a fibrous nature, with polyethylene terephthalate, nylon and polypropylene being the dominant polymers and consistent with textiles and fabrics as the principal source. Despite a distinct seasonality (temperature and wind) over the study period, the abundance, size and colour of the fibres exhibited no clear temporal trend, and no clear differences were observed between the two sites. Concentrations of MPs ranged from none detected to about 0.017/m3 (median = 0.0065/m3) and are at the low end of ranges reported in the recent literature for various urban and remote locations. While some MPs may have a local origin, the weathering of other MPs and their acquisition of extraneous geosolids and salts suggests that long-range transport is also important. Back-trajectory calculations indicate that regional sources are mainly to the north and west of Ahvaz, but a southerly, maritime source is also possible in late autumn. Although concentrations of MPs in the atmosphere are well below those encountered in indoor air, further studies are required to elucidate their potential ecological impacts.  相似文献   
96.
通过连续多年的系统监测和分析,研究了小型铅盐生产企业对周边大气、水、土壤、河流底质和农作物等生态环境的影响.研究发现,生产车间和距其100 m以外的居民区大气中铅尘分别超标548倍和4倍;500 m以外的农田土壤中铅超标1.26倍;雨水排放口附近河道水质中铅超标1.08倍;雨水排放口附近及下游800 m处的河道底质中铅分别超标1.99倍和1.33倍;500 m以外种植的小麦籽粒中铅超标16.5倍.环境污染的程度与距污染源的空间距离呈负相关.在此,还对小型重金属生产企业的环境监测和防止污染的转移提出了建议.  相似文献   
97.
In recent years, haze has posed a serious threat to the global climate change, ecological balance and human health. In this study, the laboratory experiments and field observations were performed and a possible charging mechanism was proposed to investigate the space charge properties in haze events. The laboratory experiments showed that the charge polarity of primary aerosol is determined by species of combustion fuels while the magnitude is dependent on the combustion completeness. The field observations revealed that the space charge of atmosphere aerosol in haze events differs from that of fair weather and is closely related to PM2.5 concentration when Relative Humidity (RH)?<?60%, with 1 to 2 orders of magnitude less than the case when RH?≥?60%. The analysis of equivalent charge-to-mass ratio (ECTM) suggested that in haze events the space charge is governed by primary aerosol emitted by combustion of fossil fuel in a low relative humidity, whereas it is manipulated by the secondary chemical reaction of atmosphere aerosol in a high relative humidity. And we can identify the main pollutants in haze events according to the polarity of atmosphere aerosol and quickly take measures when RH?<?60%. Accordingly, the dust-haze of RH?<?80% can be divided into dry-dust-haze when RH?<?60% and wet-dust-haze when 60%?≤?RH?<?80%. Our study firstly elucidated the space charge properties of atmosphere aerosol in haze events and can provide a new perspective for the prevention and control of air pollution.  相似文献   
98.
云贵高原1961-2006年大气能见度和消光因素变化趋势及原因   总被引:2,自引:0,他引:2  
根据云贵高原203个气象台站1961—2006年大气能见度、降水、相对湿度、风速和天气现象等观测资料,采用倾向率方法对能见度和大气消光系数的变化趋势进行了分析。还应用Mann-Kendall方法对19km能见度、霾日数和消光系数的多年变化进行了气候突变检验。结果表明,有84.2%台站出现了能见度减少趋势。减少最多为-11km·10a-1,最少为-1km·10a-1。减少的平均气候倾向率在1961—1979年为0.96km·10a-1,1980—2006年为1.6km·10a-1,高原平均能见度从60年代的约34km下降到目前的约27km。另一方面,有15.8%台站能见度有增加趋势,且多集中在人类活动较为稀少的高海拔山区。有71%的台站19km能见度频率出现减少的趋势,平均倾向率为-2%·10a-1,主要出现在高原东部和中部人口和工业稠密区。该地区同时也出现霾日增加的现象。Mann-Kendall检测结果表明,19km能见度频率减少和霾日数增加现象出现突变的时间相同。年平均消光系数发生突变的时间稍推后。认为能见度下降、消光因素增加的原因与人为排放污染物浓度增加有密切关系。  相似文献   
99.
二氧化硫光谱检测技术   总被引:2,自引:0,他引:2  
介绍了二氧化硫的性质,综述了紫外荧光分析检测技术、长程吸收光谱检测技术、激光红外吸收检测技术和遥感傅里叶变换红外光谱检测技术的原理及在二氧化硫检测中的应用。  相似文献   
100.
For the first time in Hong Kong, atmospheric radon concentration was continuously monitored between November 2007 and October 2008. This paper presents the results obtained during the 12-month period. The annual mean atmospheric radon concentration in Hong Kong was found to be 9.3 Bq m−3 which was close to the level at neighbouring places like Guangdong and Taiwan. An estimation of the dose arising from atmospheric radon to the Hong Kong population was made. The meteorological effects on the variation of atmospheric radon concentration were discussed. It was found that the origin of the airmass and stability of the local atmosphere played vital roles in the seasonal and diurnal variations respectively, whereas precipitation caused abrupt changes in rainy days. An attempt was also made to find out the contribution of atmospheric radon to the ambient gamma dose rate.  相似文献   
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