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161.
Epidemiological research underlying US air quality regulations documents significant associations between measures of fine particles and premature mortality. Recent studies examine potential mechanistic pathways, related to heart and lung functioning, that may contribute to the observed deaths. Our results support these pathophysiological analyses. We examine whether the onset of serious health conditions, consistent with disease pathways, is related to current and long-term exposure to particulate matter and ozone. Associations between air pollution and alternative indicators of health status are also evaluated. The 1996 wave of the Health and Retirement Study is used with a two-step estimator acknowledging limitations in our ability to measure individual exposures. The findings suggest significant current and long-term effects of particulates on new cases of heart attacks and angina, reinforcing the disease pathways identified in epidemiological studies. Long-term air pollution exposure is also a determinant of recently diagnosed chronic lung conditions and reports of shortness of breath. 相似文献
162.
Over the last three decades, ambient concentrations of sulfur dioxide (SO2) air pollution have declined by approximately 80%. This paper tests whether the 1970 Clean Air Act and its subsequent amendments caused this decline. The centerpiece of this legislation is the annual assignment of all counties to SO2 nonattainment or attainment categories. Polluters face stricter regulations in nonattainment counties. There are two primary findings. First, regulators pay little attention to the statutory selection rule in their assignment of the SO2 nonattainment designations. Second, SO2 nonattainment status is associated with modest reductions in SO2 air pollution, but a null hypothesis of zero effect generally cannot be rejected. This finding holds whether the estimated effect is obtained with linear adjustment or propensity score matching. Overall, the evidence suggests that the nonattainment designation played a minor role in the dramatic reduction of SO2 concentrations over the last 30 years. 相似文献
163.
Atmospheric air pollution turbulent fluxes can be assumed to be proportional to the mean concentration gradient. This assumption,
along with the equation of continuity, leads to the advection-diffusion equation. Moreover, large eddies are able to mix scalar
quantities in a manner that is counter to the local gradient. We present a general solution of a two-dimension steady state
advection-diffusion equation, considering non-local turbulence closure using the General Integral Laplace Transform Technique.
We show some examples of applications of the new solution with different vertical diffusion parameterisations. 相似文献
164.
A.?LebedevEmail author N.?Sinikova S.?Nikolaeva O.?Poliakova M.?Khrushcheva S.?Pozdnyakov 《Environmental Chemistry Letters》2003,1(1):107-112
To estimate air pollution snow samples were collected in March 2001 at six sites in the vicinity of the Kostomuksha factory
in Karelia. Seventy-two chemical elements and more than 200 individual organic compounds were identified by inductively coupled
plasma mass spectrometry (ICP-MS) and gas chromatography mass spectrometry (GC-MS). It was found that the levels of Li, B,
Al, Fe, Ni, Cu, Zn, Hg, Mn, Mo as well as hydrocarbons, phthalates and phenols exceeded the existing maximum allowable concentrations.
A list of toxicants emitted with the factory exhausts and a list of priority pollutants for Kostomuksha were compiled. The
impact of the exhausts of the Kostomuksha factory on the environment in Finland is relatively small.
Electronic Publication 相似文献
165.
Simple Spatial Modeling Tool for Prioritizing Prescribed Burning Activities at the Landscape Scale 总被引:1,自引:0,他引:1
J. KEVIN HIERS†† STEPHEN C. LAINE J. J. BACHANT† JAMES H. FURMAN‡ WELDON W. GREENE JR. § VERNON COMPTON† 《Conservation biology》2003,17(6):1571-1578
Abstract: Resources for prescribed fire are frequently insufficient to manage public lands for all conservation and resource management objectives, necessitating prioritization of the application of fire across the landscape within any given year. Defining tradeoffs when applying prescribed fire to large landscapes is problematic not only because of the complexity of weighing competing management objectives at the landscape scale, but also because of the difficult nature of independently applying need-to-burn criteria to large areas. We present a case study of a simple modeling process implemented at Eglin Air Force Base in the Florida Panhandle (U.S.A.) to prioritize the application of prescribed fire. In a workshop setting, managers and biologists identified key conservation criteria and landscape management objectives that drive the application of prescribed fire. Remote sensing and other spatial data were developed to directly or indirectly represent all these criteria. Using geographic information system software, managers and biologists weighted each criterion according to its relative contribution to overall burn prioritization, and individual values for the criterion were scored according to how they influence the need to burn. Subsequently, this process has been validated and modified through ecological monitoring. This modeling process has also been applied to the 77,400-ha Blackwater River State Forest, public land adjacent to Eglin Air Force Base, demonstrating its applicability to lands with varying management priorities. The advantages of this model-based approach for prioritizing prescribed fire include the reliance on accessible, inexpensive software, the development of spatially explicit management objectives, the ease of transferability, and clearly stated assumptions about management that may be tested and reviewed through monitoring and public comment. 相似文献
166.
本文就某金矿区在对非法开采的平硐进行毁闭爆破时产生的空气冲击波的效应进行了分析评价,指出空气冲击波对附近村庄民房不构成破坏,只是由于强烈的爆破噪音给人以恐怖感,干扰了附近居民宁静正常的生活和生产。 相似文献
167.
介绍了组合式空气消声过滤器的用途、结构、工作原理和使用效果,它是空气压缩机前级的专用理想设备,推广使用后可获得良好的综合效益。 相似文献
168.
沙尘天气对环境空气中PM_(10)影响分析 总被引:4,自引:1,他引:4
利用2002年沈阳市沙尘天气时的环境监测资料和气象资料进行分析得出浮尘天气时环境空气中PM10浓度最大,空气污染最严重,空气中的尘主要来源于我国西北沙漠地区;沙尘暴出现频率低,持续时间短,但强度大,空气中PM10主要来源科尔沁沙漠、省内荒漠地带及本市地表沙尘;扬沙天气污染相对较轻,空气的PM10以本地地表尘为主。 相似文献
169.
大气环境质量功能体系及其评价中的系统观 总被引:2,自引:0,他引:2
应用系统理论,论证了环境质量作为一种功能体系存在的客观性,并分析了该体系的基本特点及与人类需求层次相协调的性质,从而将环境质量拓展为一种广义的概念以顺应经济、社会发展和环境科学发展的要求.进而就大气环境质量功能体系,探讨了认识和评价环境质量的一般方法以及系统科学在环境科学领域中的应用. 相似文献
170.
郑州大气氮氧化物污染与灰色分析 总被引:2,自引:0,他引:2
通过对郑州市大气中NOx的监测和分析,初步揭示了NOx变化的规律。同时,运用灰色关联度分析,定量地分析了影响郑州市NOx变化的因素。并建立了该市的NOx产生量的GM(1,1)预测模型。结果表明:(1)影响NOx污染的主要因子是家庭用气普及率;(2)NOx在大气中的浓度呈逐年下降的趋势,2002年预测值为0.043mg/m^3。 相似文献