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111.
室内空气中污染物的检测技术   总被引:3,自引:0,他引:3  
室内环境空气污染对人体健康影响很大,文中指出了影响人体健康的致病因子,分析了单个微粒的光通量和粒径之间的关系。鉴于单下颗粒的散射光信号很弱,本文提出一种方法,把激光器的内腔作为颗粒注入区,利用激光器的内腔功率谱密度远大于腔外功率密度的特点,结合先进的激光散控制理论,对空气中的颗粒进行检测。  相似文献   
112.
Pollution distribution maps of copper (Cu), zinc (Zn) and lead (Pb) for Erzurum province were developed on the basis of chemical analysis of Scots pine (Pinus sylvestris L.) needles collected from randomly selected sampling points during 2 years. The maps show deposition zones for the studied elements and could help in identification of sources and directions of air pollution dispersion. This study indicated that vegetation in Erzurum was greatly endangered by sulphur dioxide (SO(2)), whereas Zn does not pose an immediate threat to vegetation in most of the country's territory. However, in the city center, main and secondary road agglomeration, very high pollution with Pb and Cu could limit growth. Higher levels of SO(2) measured in some areas of Erzurum might be harmful for human and animal health. Results of this study indicated that Scots pine needles were not contaminated by Zn.  相似文献   
113.
114.
Q1, an organochlorine component with the molecular formula C(9)H(3)Cl(7)N(2) and of unknown origin was recently identified in seal blubber samples from the Namibian coast (southwest of Africa) and the Antarctic. In these samples, Q1 was more abundant than PCBs and on the level of DDT residues. Furthermore, Q1 was more abundant in seals from the Antarctic than the Arctic. To prove this assumption, gas chromatography-electron-capture negative ion mass spectrometry (GC/ECNI-MS), which is sensitive and selective for Q1, allowed for screening of traces of Q1 even in samples with particularly high levels of other organochlorine contaminants. Q1 was isolated by high-performance liquid chromatography (HPLC) from a skua liver sample. A 1:1 mixture with trans-nonachlor in electron-capture detectors (ECDs) was used to determine the relative response factor with ECNI-MS. The ECNI-MS response of Q1 turned out to be 4.5 times higher than that of trans-nonachlor in an ECD. With GC/ECNI-MS in the selected ion-monitoring mode, four Antarctic and four Arctic air samples were investigated for the presence of Q1. In the Antarctic air samples, Q1 levels ranged from 0.7 to 0.9 fg/m(3). In Arctic air samples, however, Q1 was below the detection limit (<0.06 fg/m(3) or 60 ag/m(3)). We also report on high Q1 levels in selected human milk samples (12-230 microg/kg lipid) and, therefore, suggested that the unknown Q1 is an environmental compound whose origin and distribution should be investigated in detail. Our data confirm that Q1 is a bioaccumulative natural organochlorine product. Detection of a highly chlorinated natural organochlorine compound in air and human milk is novel.  相似文献   
115.
The body of information presented in this paper is directed to air pollution engineers who are concerned with the effect of indirect sources on ambient concentrations of carbon monoxide (CO). Data taken under controlled conditions are used to empirically derive and calibrate a model for predicting CO concentrations in the vicinity of roadway intersections and other points of possible vehicular congestion. Since the predicted free flow CO contribution of vehicles traveling at normal road speeds is relatively low, it is concluded that idling vehicles at points of congestion are the major cause of CO violations, and that state and federal programs should place more emphasis on relieving congestion and reducing idling emission rates in new vehicles.  相似文献   
116.
Relative to manufacturing, service activities are often considered by planners and officials to generate considerably less environmental pollution. This hypothesis is tested by means of an examination of the economic linkages of both manufacturing and service activities and of the resulting direct and indirect emissions of five air pollutants per dollar of output in the California statewide air basin and in four regional basins within the state. Overall acceptance or rejection of the hypothesis depends in part on the particular pollutant and air basin considered but, most importantly, on the judgement as to what activities are to be considered as service activities.This paper is based on research sponsored by the California Air Resources Board under Agreement A7-143-30.  相似文献   
117.
Climate change mitigation and air quality management are mostly addressed separately in South African legal acts and policies. This approach is not always coherent, especially in the context of other serious issues South Africa is facing, such as poverty alleviation. Policies implemented to mitigate climate change might increase negative health affects due to unanticipated outcomes (e.g. increased local air pollution), and these indirect consequences must therefore be taken into account when devising mitigation strategies. However, greenhouse gas mitigation policies can also have co-benefits and positive impacts on local air pollution. An evidence-based approach that takes into account greenhouse gas emissions, ambient air pollutants, economic factors (affordability, cost optimisation), social factors (poverty alleviations, public health benefits), and political acceptability is needed tackle these challenges. A proposal is made that use of an integrated climate/air pollution techno-economic optimising model, such as the Greenhouse Gas and Air Pollution Synergies (GAINS) model, may provide a rational decision support tool to guide policy makers into effective strategies for combined Climate Change and Air Quality mitigation measures.  相似文献   
118.
Ecosystem functions can be understood as the quantified amount of an ecosystem’s role in a natural process, while ecosystem services are the requantification of the ecosystem functions by factoring in environmental conditions and human needs based on social perspectives. In this study, differences between ecosystem functions and services were presented in terms of air purification of a forest ecosystem. Forest volume growth was employed to quantify the pollutant absorption capacity of a forest and was indicated by the natural functions (NF) for air purification by a forest ecosystem. Forest ecosystem services can be requantified from the forest functions by adding the air pollutant and population densities. Air pollutant density was applied to the assessment of the environmental services (ES) of forest ecosystems. Furthermore, the environmental social services (ESS) of forest ecosystems were assessed by including population density considerations. We simulated differences in NF, ES, and ESS in relation to pollutant and population density; while NF was spatially quantified without a close relationship to air pollutant and population density, ES and ESS reacted to environmental and social condition more sensitively. These results imply that the ecosystem services of forest resources for air purification are high where the pollutant and population densities are high, while the ecosystem functions of forest resources for air purification depend solely on forest conditions and not on the density changes of air pollutants and population. This study suggests that the differences in NF, ES, and ESS are important factors to be understood and considered in the decision-making process for ecosystem services. When considering human needs and surrounding environmental conditions, the results suggest that decision makers should utilize the ES and ESS concepts, which reflect both population and pollutant density along with additional human-related factors.  相似文献   
119.
A plenty of studies on the utilization of biomass alcohol fuels have been conducted, but combustion efficiency and stability of this fuels still need to be improved. Based on biomass alcohol fuels (bio-methanol and bio-ethanol), this paper studied auto-adaptive air distribution characteristics and optimum structure parameters of an ejector burner by numerical simulation method. Also, an experiment was conducted to verify the numerical results. The results show that the mole air entrainment ratio (MAER) keeps almost constant when the ejector fuel nozzle exit locates at the segment between the ejector throat and the suction chamber entrance, but a bigger ratio α would lead to a higher MAER till the α is bigger than 8.5 for bio-methanol and 11.5 for bio-ethanol. The bio-ethanol fuel is more beneficial for air carrying role because of its big molecular weight. Operation pressure (Pw) has a little impact on MAER of the two fuels, but the rise of back pressure (Pb) would lead to rapid decrease of MAER for the two fuels. For the optimum structure burners, the MAER can be maintained at the value of theoretical complete combustion. Its changing rate is less than 2.3% for bio-methanol and 2.5% for bio-ethanol when the burner load changes from 30% to 120%, which is highly consistent with the experimental results. The optimum burner can distribute air supply automatically with the changing of burner load.  相似文献   
120.
The concentrations of phthalate esters(PAEs) in Chinese hospitals were investigated by simultaneously determining concentrations of gas- and particle-phase PAEs. PAEs were detected in two third-class first-grade hospitals, two second-class first-grade hospitals, and a community health service center. Hospital drugstores had the highest concentration(24.19 μg/m3), which was 1.54 times that of newly decorated houses. The second highest concentration was found in the transfusion rooms, averaging 21.89 μg/m3; this was followed by the concentrations of PAEs in the nurse's workstations, the wards, and the doctor's offices, with mean concentrations of 20.66, 20.0, and 16.92 μg/m3, respectively. The lowest concentrations were found in the hallways(16.30 μg/m3). Of the six different kinds of PAEs found, major pollutants included diethyl phthalates, dibutyl phthalates, butylbenzyl phthalates and di(2-ethylhexyl) phthalates, comprising more than 80% of all PAEs present.Meanwhile, a comparison between different wards showed that PAE concentrations in the maternity wards were 1.63 times higher than in the main wards. Based on known health hazards, our results suggest that the PAEs seriously influence the health of the pregnant women and babies; therefore, it is of great importance to take the phthalate concentrations in hospitals into consideration. In addition, hospital indoor air was more seriously contaminated than the air of newly decorated houses.  相似文献   
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