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1.
综述了芳香污染物、金属和金属纳米颗粒、抗生素等3种污水中常见微量污染物对厌氧氨氧化(Anammox)菌群的抑制效应,分析了导致Anammox活性丧失的抑制机理,指出抑制作用多表现为对细胞膜的损害,抑制效果受污染物在细胞质中扩散、溶解和摄入细胞能力的影响。针对不同的污染物提出了相应的应对策略,可以通过淘洗菌种、投加新鲜种群、添加促进剂等方式提高Anammox活性和胞外聚合物(EPS)含量,也可以利用驯化手段诱导抗性基因的产生,或采用生物膜法增强Anammox群落对污染物的耐受性。  相似文献   

2.
分析了环保行政主管部门监测站在污染源监测工作中的地位与作用,指出环保主管部门监测站的主要任务是对辖区内排污单位的污染物排放监测工作质量进行监督,以促进排污单位认真监测、如实申报,保障辖区内污染源监测工作的规范、有序运行,并负责了解、掌握辖区内的总体污染物排放情况。  相似文献   

3.
水污染源源解析研究最新进展   总被引:4,自引:2,他引:2  
采取有效措施监测监管污染物排放是实现污染减排目标的必要条件,而准确掌握流域内污染物的来源是实现污染源有效监管的技术依据,文章对水污染源源解析目标化合物选取、污染物扩散模型研究和污染区域受体模型研究的最新进展进行了评述,对其发展趋势进行了展望.  相似文献   

4.
居室内空气污染监测刻不容缓   总被引:1,自引:0,他引:1  
本文所指的居室包括了人们休息、睡眠、学习、工作以及公共场所等.1.居室内空气中的污染物和来源居室内的污染物除了来源于室外的大气污  相似文献   

5.
企业污染物排放达标率统计计算的探讨狄凌峰(浙江温岭市环境监测站,温岭3175)())本文提出企业污染物排放达标率为各污染物达标率的加权算术平均值,加权的大小取决于各污染物对环境的危害程度,其统计结果可综合体现治理和环境效果,表达式为:。。一,。一一、...  相似文献   

6.
公路隧道内运动汽车尾气污染扩散数值仿真研究   总被引:1,自引:0,他引:1  
利用计算流体力学(CFD)方法,结合标准k-ε湍流模型、Mixture混合多相流模型和动网格技术,数值仿真了公路隧道内运动汽车的尾气污染扩散,结果与实验测量值吻合较好。表明,在没有其他通风方式的公路隧道内,运动汽车排出的污染物主要分布在近地面;运动汽车后方会形成1条高速风带,对隧道内污染物纵向扩散具有关键作用。  相似文献   

7.
在污水处理效果评价过程中,确切计算污水去除率是评价污水处理效果的依据之一。用不同的评价模式及方法则得到不同的评价结论,给污水处理设施验收结果带来影响。因此,综合多方面的定性、定量因素,并将这些因素有机地结合起来,应用数理统计法建立一种污水去除率评价方法是十分必要的。1 评价方法的建立在常规去除率评价中,应用以下2种模式:方法一,在污水排放高峰时间取处理前、处理后水样,测定污染物浓度,计算去除率;方法二,在一段时间内每间隔相同的时间取处理前、处理后水样,测定污染物浓度,计算去除率。这2种方法均忽略…  相似文献   

8.
采用城市绿地和降雨系统模拟装置,研究绿地系统对径流污染物的净化机理。研究表明,模拟绿地对径流污染物的削减和污染物总量的控制有较好作用。降雨0.5h内污染物质主要被0cm-15cm层土壤所吸附,2h后各层对有机质、氮磷的吸附能力基本相同。绿地系统对径流污染物中COD、NH4^+ -N、NO3^- -N及TP去除率为37.6%~49.9%;降雨期间污染物的去除主要靠土壤和植物根系的截留、吸附和吸收作用,因此对土壤NH4^+ -N、NO3^- -N及TP的吸附过程用Langmiur方程进行拟和,发现土壤对NH4^+ -N及TP的吸附反应在常温下自发进行程度较强,对NO3^- -N的吸附反应在常温下较难进行。且降雨后微生物开始降解吸附于土壤颗粒表面和植物根系的污染物,降雨后第5d~8d,土壤中微生物数量达到最大值,说明雨后土壤中污染物的降解主要发生在降雨后第2d-8d内,且t4d~17d土壤污染物含量基本降到降雨前水平,土壤得到再生.  相似文献   

9.
中国中东部一次大范围重污染过程特征分析   总被引:1,自引:1,他引:0  
采用嵌套网格空气质量预报模式(NAQPMS)模拟与气象、污染物观测资料相结合的方式,分析了2016年12月影响中国中东部地区的一次重污染过程中PM_(2.5)时空分布特征及来源成因。结果表明,重污染过程中PM_(2.5)具有较明显的时空变化规律,污染呈现一定程度的区域性分布特点,不同地理位置条件下,污染物浓度的累积和传输方式表现出不同的特征,细颗粒物快速二次生成及不利扩散条件下的持续积累可能是此次污染过程的主要原因,不利于污染物扩散的高低空天气形势的配合抑制了污染物的快速消散,为大气污染的形成及维持提供了稳定的大气环境背景,形成了此次污染过程污染浓度高、影响范围大的态势。  相似文献   

10.
利用2017—2019年滁州市6种空气污染物质量浓度和AQI资料、气象要素及ECMWF数值预报作为输入参数,构建基于随机森林算法的污染物质量浓度和AQI预报模型,其中AQI预报按季节划分为4个模型。结果表明:6种污染物中O3的预报效果最好,相关系数为0.84,PM2.5、PM10和NO2相关系数分别为0.76、0.72和0.72,SO2和CO预报效果略差;基于分季节模型AQI的24 h预报结果TS评分为0.77,空报率(FAR)和漏报率(PO)分别为15%和12%,相较于非季节模型预报效果更好;春季和秋季的TS评分分别为0.88和0.86,相较于冬季和夏季预报效果更好。  相似文献   

11.
空气净化器可有效改善雾霾天气下室内空气质量,颗粒物去除效果与洁净空气量(CADR)是衡量其性能的主要参数。在典型室内环境下,以香烟源颗粒物为目标,开展空气扰动对净化器去除颗粒物效果和CADR的影响实验与评价分析。结果显示,在室内空气扰动下,净化器对粒径≥5μm的颗粒物去除率为75.6%,在无空气扰动情况下的去除率为46.6%。空气净化器对粒径0.3μm^5μm的颗粒物有较好的去除效果,而对于粒径10μm的较大颗粒物,空气扰动造成CADR增加。空气扰动在一定程度上提升了空气净化器的净化能力,同时在性能方面也存在影响。  相似文献   

12.
南京市一次连续空气污染过程的气象条件分析   总被引:1,自引:0,他引:1  
利用空气污染资料、常规气象观测资料、NCEP每6h一次2.5°×2.5°再分析资料及NOAA(美国国家海洋和大气管理局)的GDAS(全球同化数据)资料,对2009年10月16日—30日南京市出现一次连续15d的空气污染过程的天气特征进行诊断分析,同时使用HYSPLIT-4后向轨迹模式对污染物来源进行模拟。结果表明:不利于污染物扩散的大气环流形势和气象要素是造成此次污染的主要原因。南京污染物的来源可以大致分为3类:一类是海上来源;一类是南京本地的局地污染来源;还有一类是北方污染物的输送。这为进一步研究长三角地区城市的空气污染来源和成因提供理论依据。  相似文献   

13.
Air inside poultry houses must be removed on a regular basis to prevent excess of heat, particles and noxious gases that can imperil animals. To cope with this issue, natural ventilation could be an effective method when assisted by accurate predictions. This study investigates air discharges caused by natural ventilation of a poultry house by means of a three-dimensional computational fluid dynamics (CFD) model. It solves the governing equations of momentum, heat and mass transport, radiative transfers and animal-generated heat. Wind directions of 0°, 36° and 56° (0° corresponds to a wind blowing perpendicular to the ridgeline) were investigated; the CFD model predictions achieved a RMSE of 1.2 °C and 0.6 g[H2O] kg?1 [dry air] for internal temperature and absolute humidity, respectively, when air blew with an angle of 36°. Air renewal rates (ARR) were 39.5 (±?1.9), 34.9 (±?2.2) and 33.6 (±?1.7) volumes of the building per hour, when air blew at 0°, 36° and 56°, respectively. Such ARR predictions served to know how the gases contained in air would likely spread downstream from the building in order to define regions of potentially high gas concentration that could endanger neighbouring habitable facilities.  相似文献   

14.
The microbiological quality in dental unit waterlines (DUWLs) is considered to be important because patients and dental staff with suppressed immune systems are regularly exposed to water and aerosols generated from dental units (DUs). Opportunistic pathogens like Pseudomonas, Legionella, Candida, and Aspergillus can be present in DUWLs, while during consultations, bioaerosols can be dispersed in the air, thus resulting in effects on microbiological quality of indoor air. This present study represents microbiological air and water quality in dental offices (DOs) and also concerns the relationship between the quality of DO air and dental unit water. This study aimed to assess both the microbial quality of dental unit water and the indoor air in 20 DOs and to survey the effect on the quality of the indoor air with the existing microorganisms in dental unit water. Fourteen out of 20 (70 %) DUWLs were found to be contaminated with a high number of aerobic mesophilic heterotrophic bacteria. In terms of bacterial air contamination levels, in 90 % of DOs, a medium level (<500 colony-forming units (CFU)/m3) of contamination was determined, while in terms of microfungal air contamination, in all DOs, a low level (<100 CFU/m3) of contamination was determined. Potential infection or allergen agents, such as Pseudomonas, Micrococcus, Staphylococcus, Alternaria, Cladosporium, Penicillium, Aspergillus, and Paecilomyces were isolated from water and air samples. This study’s determination of contamination sources and evaluation of microbial load in DOs could contribute to the development of quality control methods in the future.  相似文献   

15.
杭州主城区大气臭氧对空气污染指数API的影响   总被引:10,自引:8,他引:2  
利用2004年至2007年空气污染监测数据,比较现行API指数和修正后API指数的差异,分析修正后O3污染的变化状况,研究O3污染的季节变化。结果表明,O3作为一种新的空气污染指标,对修正后API指数的影响很大。与现行API指数相比,4年来修正后API指数的污染率大幅度增加,并且各季节的污染率越来越接近,2007年污染率在25%左右。2007年各季节修正后API指数污染天数中O3污染天数所占百分比分别是春季为52%、夏季91.6%、秋季20.8%、冬季O3,未出现污染。  相似文献   

16.
Surface data of meteorological parameters (wind speed, wind direction, and mixing height) and air pollutant concentrations (O3, NO, and NO2) were collected for a 92-day period associated with typhoon formation in 2005. The influence of typhoons on O3 concentration were defined by azimuth and distance from Taiwan, and Types A, B, and C correspond to typhoons less than 1,500 km from Taiwan and located between azimuths 45° and 135°, 135° and 225°, and 225° and 45°, respectively. Type D corresponds to typhoons more than 1,500 km from Taiwan. Titration reactions were conducted at three temporal phases: 2000–0700, 0800–1100, and 1200–1400 LST (Local Standard Time). The air pollution model (TAPM) was used to simulate wind fields and trajectories of air masses. It was determined that typhoon position affected O3 concentration, temporal and spatial patterns of O3 titration and vertical meteorological characteristics, which were not all at the statistically significant level.  相似文献   

17.
洛阳市空气微生物污染初步调查   总被引:2,自引:0,他引:2  
采用平皿沉降法对洛阳市空气微生物浓度进行了初步测定。结果表明:空气细菌、真菌和总菌的浓度分别为7448CFU/m^3、782CFU/m^3和9063CFU/m^3,真菌与总菌的浓度比值为8.64%,空气质量处于微污染水平;空气微牛物浓度空间差异显著,可分为中度污染、轻度污染、微污染和较清洁4个等级;从功能区划看,商业交通混合区污染最重,生活区和工业区空气质量最好;空气污染微生物主要为G^+球菌和交链孢,其次还有少量芽孢杆菌和青霉、曲霉、毛霉等。  相似文献   

18.
In the summer of 2003, ambient air concentrations of volatile organic compounds (VOCs) were measured at 12 sites within a 3-km radius in Deer Park, Texas near Houston. The purpose of the study was to assess local spatial influence of traffic and other urban sources and was part of a larger investigation of VOC spatial and temporal heterogeneity influences in selected areas of Houston. Seventy 2-h samples were collected using passive organic vapor monitors. Most measurements of 13 VOC species were greater than the method detection limits. Samplers were located at 10 residential sites, a regulatory air monitoring station, and a site located at the centroid of the census tract in which the regulatory station was located. For residential sites, sampler placement locations (e. g., covered porch vs. house eaves) had no effect on concentration with the exception of methyl tertiary-butyl ether (MTBE). Relatively high correlations (Pearson r > 0.8) were found between toluene, ethylbenzene, and o,m,p-xylenes suggesting petroleum-related influence. Chloroform was not correlated with these species or benzene (Pearson r < 0.35) suggesting a different source influence, possibly from process-related activities. As shown in other spatial studies, wind direction relative to source location had an effect on VOC concentrations.  相似文献   

19.
利用2015年10月福州市国控点位空气质量常规6项参数(SO_2、NO_2、CO、O_3、PM_(10)、PM_(2.5))、NCEP/NCAR再分析逐日高度场、风场资料、温度场资料(垂直方向为17层,分辨率为2.5°×2.5°),对10月及福州第一届青年运动会(以下简称"青运会")期间空气质量进行分析与评价,并结合采取的相关管控措施和气象条件情况,分析福州市空气质量变化原因。结果表明,2015年10月福州市空气质量达到优良水平,各项污染物指标均达到一级标准,浓度较2014年同期明显下降,同时青运会期间污染物浓度较10月显著降低,这与对重点工业源、流动源、扬尘源等采取的管控措施密不可分,而且青运会前期受台风"巨爵"外围气流影响,福州温度较常年偏高,有利于空气垂直湍流运动,青运会后期的降水清洁过程,易于污染物清除。  相似文献   

20.
Abstract Industrial development and consumption of petroleum products leads to increase air pollution levels especially in urban and industrial areas. Heavy metal components associated with air pollutants have far reaching effects with respect to economic and ecological importance of pollens. The pollens are male reproductive organs of the plant and travel through air from flower to flower for pollination purpose. During this period they are exposed to air pollutants. Present investigation thus pertains to study of effect of air pollutants on pollens especially biosorption and bioaccumulation of heavy metals. The pollens of three commonly occurring plants namely Cassia siamea, Cyperus rotundus, Kigelia pinnata have been studied from the NH-6 of Nagpur city, India. The pollens exposed to polluted air showed the presence of higher concentrations of Ca, Al and Fe as compared to unexposed pollens. Higher concentration of these metals was observed in Cyperus rotundus followed by Cassia siamea and Kigelia pinnata. These results indicate that pollens act as good indicator of air pollution giving results in short time of exposure of 5–10 h. Apart from this, it is also reported that some of these metals play crucial role in the metabolic activity in pollens for example Calcium is necessary for growth of pollen tube and other metabolic activities in pollens. The presence of these metals in pollens may also enhance the allergenicity of the pollens. Similarly accumulation of heavy metals may also deteriorate the quality of pollen for their economical use. The viability of pollen is also affected by these pollutants in sensitive species leading to impairment of their fertility.  相似文献   

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