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 共查询到18条相似文献,搜索用时 125 毫秒
1.
对上海市6个监测点位2001年-2004年不同月份环境空气中的TSP和PM10的变化趋势进行了分析。并使用数理统计模式,就环境空气中TSP和PM10之间的相关性进行了探讨,得到了较为理想的结果。  相似文献   

2.
浅析环境空气中颗粒物TSP、PM10的相关性   总被引:1,自引:0,他引:1  
对上海市6个监测点位2001年~2004年不同月份环境空气中的TSP和PM10的变化趋势进行了分析.并使用数理统计模式,就环境空气中TSP和PM10之间的相关性进行了探讨,得到了较为理想的结果.  相似文献   

3.
辽宁省典型城市大气中颗粒物污染状况及分布特征研究   总被引:2,自引:0,他引:2  
研究了辽宁省典型城市大气中不同粒径颗粒物污染状况及分布特征,结果表明大气中TSP、PM10、PM2.5三种不同粒径颗粒物污染较重,颗粒物中PM10及以下细小颗粒所占比例较高.  相似文献   

4.
针对常用大气颗粒物监测系统稳定性差,集成度低,测试耗时,TSP、PM10及PM2.5数据"倒挂"等问题,提出一种基于PLC的三通道β射线大气颗粒物连续自动监测系统。系统以β射线吸收原理为基础,采用PLC控制技术,以HMI为人机界面,实现了TSP/PM10及PM2.5 3种颗粒物质量浓度同时检测。监测系统三通道共用动态加热系统,减少了高湿度差异情况下的数据"倒挂"现象。使用称重法作为参比方法对样机进行比对测试,TSP、PM10及PM2.5质量浓度与称重法质量浓度的相关系数均大于0.95,能够准确地反映测试环境的颗粒物实际水平。  相似文献   

5.
气溶胶细粒子与能见度的相关性   总被引:7,自引:1,他引:6  
为了分析气溶胶粒子特别是细粒子(PM2.5)对能见度的影响,从理论上建立了气溶胶细粒子与能见度的关系,分析了谱分布的变化对PM2.5/PM10和细粒子消光所占总消光比重的影响.对测量数据与理论计算结果进行了对比分析,结果表明:所建立的气溶胶细粒子与能见度的关系是合理的,理论计算的误差小于30%,这对治理污染和提高城市能见度具有指导意义.  相似文献   

6.
气溶胶细粒子与能见度的相关性研究   总被引:1,自引:0,他引:1  
李学彬 《光学精密工程》2008,16(7):1177-1180
为了分析气溶胶粒子特别是细粒子(PM2.5)对能见度的影响,本文从理论上建立了气溶胶细粒子与能见度的关系,分析了谱分布、PM2.5/PM10和细粒子消光所占总消光比重的关系。利用2004年8月在北京的测量数据与理论计算对比表明:建立的气溶胶细粒子与能见度的关系是合理的。这对治理污染提高城市能见度是很有指导意义的。  相似文献   

7.
为研究厦门市大气颗粒物的污染特征及其对酸雨的影响,于2012年12月至2013年7月在厦门市各区分别采集大气中TSP、PM10、PM2.5颗粒物样品,利用离子色谱法分析了其中的水溶性离子成分含量。结果表明,厦门市大气颗粒物中水溶性离子成分分布特征为:Na+和Ca2+离子主要主要分布在TSP、PM10中,而SO42-离子则主要分布在PM10和PM2.5中。说明Na+和Ca2+离子更容易富集在粗颗粒物粒子上,而SO42-离子主要存在于细颗粒物粒子中。厦门市大气颗粒物中对雨水酸度有重要缓冲作用的Ca2+、Mg2+离子浓度处于较低水平,说明厦门市大气颗粒物对雨水酸度缓冲作用较低,这是厦门地区酸雨发生率较高的原因之一。  相似文献   

8.
大气气溶胶碳组分存在形式多样,其化学和光学特征明显不同;因此基于不同的热和光行为的假设和分析步骤的碳组分分析方法导致碳组分测量结果的差异。本文基于文献调研与实验室分析介绍气溶胶碳组分分析仪器的基本性能指标,分析不同分析方法导致气溶胶碳组分的差异和成因。为了了解北京有机气溶胶特征,本文描述北京PM2.5中有机碳(OC)和元素碳(EC)变化特征并对北京秋、冬季PM,(大气中空气动力学直径≤1μm的颗粒物)中有机气溶胶进行了来源解析。结果表明,北京OC和EC在秋冬季呈现出较高的水平,采暖期OC浓度是非采暖期的1.2—1.8倍,EC浓度是非采暖期的1.1倍左右;秋季北京PM,中有机气溶胶(OA)主要来源于二次转化产生的氧化性有机气溶胶(OOA),机动车排放的烃类有机气溶胶(HOA)和餐饮排放有机气溶胶(COA);而冬季北京PM1中有机气溶胶主要来源于高度氧化的低挥发性的OOA,“新鲜”氧化的半挥发性的OOA,燃煤源有机气溶胶(CCOA)、烹饪源排放的COA和机动车排放的HOA。  相似文献   

9.
为了从相干多普勒测风激光雷达的微弱气溶胶后向散射信号中高效、准确地提取多普勒频移信息,得到最接近CRB极限的无偏估计,利用气溶胶后向散射信号统计特性,建立了相干多普勒激光雷达仿真模型,并用最大概似法(ML)推导了在功率谱宽度已知情况下多普勒频率的估计算法。利用1.54μm全光纤相干激光雷达系统获得风场测量数据,用ML算法进行多普勒频移估计,并将结果与传统的周期图最大值法(PM)所得结果进行比较。对比表明,ML算法与PM算法的数据处理结果有较好的一致性,并且ML算法的多普勒频率探测能力更优。  相似文献   

10.
文章利用淮安、泰州和太仓3地的气溶胶激光雷达、风廓线雷达及探空等综合观测资料,根据观测期间的气象特征和大气能见度与近地面PM10观测数据,从卫星观测结果、激光雷达组网以及沙尘传输路径三方面分析了江苏地区2017-04-17~2017-04-19的1次浮尘天气过程中气溶胶的垂直结构,为大气重污染成因研究提供立体观测数据,为重污染天气应对提供数据支撑。  相似文献   

11.
在北京空气重污染期间,以石英膜采集的PM2.5为样本,采用飞行时间二次离子质谱(TOF-SIMS)结合质量高分辨模式与正负离子成像模式表征了PM2.5-铵。实验观察到了硫酸氢铵(NH4HSO4)单颗粒物,未见硝酸铵或氯化铵。实验验证了正、负离子成像之间微米级偏差的人工校正方法,同时阐明了TOF-SIMS表征PM2.5水溶性无机盐等成分的特点、优势和应用潜力。  相似文献   

12.
Atomic force microscopy (AFM) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) have been used for both morphological and elemental mass analysis study of atmospheric particles. As part of the geometrical particle analysis, and in addition to the traditional height profile measurement of individual particles, AFM was used to measure the volume relative to the projection area for each particle separately, providing a particle shape model. The element identification was done by the EDS analysis, and the element mass content was calculated based on laboratory calibration with particles of known composition. The SEM-EDS mass measurements from two samples collected at 150 and 500 m above the surface of the Mediterranean Sea were found to be similar to mass calculations derived from the AFM volume measurements. The AFM results show that the volume of most of the aerosols that were identified as soluble marine sulfate and nitrate aerosol particles can be better estimated using cylindrical shapes than spherical or conical geometry.  相似文献   

13.
This article reviews current scientific literature focusing on Raman spectroscopy modalities that have been successfully applied to the detection of biological samples in aqueous suspensions and in aerosols. Normal Raman, surface enhanced Raman scattering, coherent anti-stokes Raman scattering, resonance Raman and UV-Raman spectropies, allow the detection of biological samples in situ in the near field and as well as in the far field at standoff distances. Applications span from fundamental studies to applied research in areas of defense and security and in monitoring of environmental pollution. A primary focus has been placed on biological samples including bacteria, pollen, virus, and biological contents in these specimens, in suspensions, and in aerosols. Several Raman spectroscopy studies have been reviewed to show how various modalities can achieve detection in these biosystems. Current data generated by our group is also included. Necessary parameters used to accomplish the detection and data analysis, which could also be used to interpret the results and to render the methodologies robust and reliable, are discussed.  相似文献   

14.
This paper introduces the use of temperature-sensitive paint (TSP) to obtain the whole-field temperature distributions in heat transfer enhancement applications. Knowing the surface temperatures in such applications is important to quantify the heat transfer, as well as to obtain insight into the flow physics. Applying the TSP to a flat plate with and without a vortex generator showed that the TSP Nusselt number distribution over the flat plate alone matched the Blasius solution with less than 10% error. The TSP temperature distribution of the flat plate with the delta wing vortex generator showed a local heat transfer enhancement of about 30% and the locations of temperature extremes. This paper also provides a detailed guideline for the application, image acquisition, and image processing procedures for TSP along with its calibration surfaces.  相似文献   

15.
本文通过采用膜去溶进样系统与 ICP-MS联用技术和同位素稀释质谱法定量分析了大气气溶胶样品中 fg量级的钚。方法对大气中 2 39Pu的定量限达到了 5 .7× 1 0 -8Bq/ m3。膜去溶系统的使用提高了样品的利用效率 ,并有效降低了复合离子 2 38U1H+对 2 39Pu测定的影响 ,使仪器的分析灵敏度 (相对 )提高了近一个数量级 ,对 2 39Pu的检出限达到了 0 .4 fg/ m L。  相似文献   

16.
Real-time single particle mass spectrometry, or continuous aerosol mass spectrometry, was originally developed in the 1970s for the purpose of identifying the chemical composition of airborne particulate matter in real-time. Although this technique has continued to evolve throughout the following decades, the fundamental characteristic of this method remains the same, involving the continuous introduction of solid particle or liquid droplets directly into the ion source region of a mass spectrometer. Continuous sample introduction allows for the chemical analysis of single airborne particles in real-time. A number of mass analyzers have been employed in real-time single particle mass spectrometry. The original real-time single particle mass spectrometer used a magnetic sector mass analyzer. Quadrupole, double-focusing, and ion trap mass spectrometers have also been utilized. The majority of the current real-time single particle mass spectrometry techniques use time-of-flight mass spectrometry. In the literature, a variety of general names have been applied to real-time single particle mass spectrometry methods. These names include direct-inlet mass spectrometry, on-line laser microprobe mass spectrometry, particle analysis by mass spectrometry, particle beam mass spectrometry, and rapid-single particle mass spectrometry. This review covers real-time single particle mass spectrometry techniques that were developed from 1973 through 1998, specifically for analyzing airborne particulate matter, including environmental aerosols, biological aerosols, and clean-room aerosols. Because the majority of the historical and current real-time single particle mass spectrometers have been employed for atmospheric aerosols, this topic is the primary focus of this review. This review does not include on-line mass spectrometry methods that are employed as a detector for other instrumental methods, such as liquid chromatography.  相似文献   

17.
研制了一种高灵敏度在线膜进样真空紫外电离源飞行时间质谱仪(MI-SPI-TOF MS)用于检测低浓度挥发性有机物(VOCs)。仪器包括真空系统、膜进样接口、真空紫外单光子电离源、垂直加速反射式飞行时间质量分析器和数据采集系统等。该仪器使用聚二甲基硅氧烷(PDMS)膜作为大气压下直接进样的接口,膜的选择透过性能直接、快速地富集大气中VOCs,可实现快速在线进样检测。真空紫外单光子灯作为电离源,能将电离能低于10.6 eV的VOCs电离,形成分子离子峰。结果表明,该仪器的分辨率优于750 FWHM,对苯、甲苯、二甲苯和氯苯的检测限达10-12 mol/mol级别,检测速度达秒级,可用于低浓度VOCs的实时在线检测。  相似文献   

18.
厦门大气可吸入颗粒物离子成分特征研究   总被引:4,自引:0,他引:4  
采集厦门冬、春、夏三季大气颗粒物PM10,冬、夏两PM2.5样品,用IC进行离子成分分析,结果表明:厦门大气颗粒物水溶性离子成分呈春冬季高、夏季低的季节变化特征。二次离子SO4^2-、NO3^-与NH4^+占PM10的近40%,海盐离子占7%;二次离子占PM2.5的48%,海盐离子占3%。二次离子污染是影响厦门环境空气质量的主要因子。  相似文献   

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