Atmospheric Environment (1967)最新文献

A review of recent field tests and mathematical modelling of atmospheric dispersion of large spills of Denser-than-air gases 最近现场试验的回顾和比空气密度大的气体泄漏在大气中扩散的数学模型

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90475-7

Ronald P. Koopman, Donald L. Ermak, Stevens T. Chan

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引用次数: 43

Background trends of pH of precipitation over India 印度降水pH值的背景趋势

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90476-9

G.S. Varma

引用次数: 22

A simulation of wind and air pollution over complex terrain using a hydrostatic numerical model 用流体静力数值模式模拟复杂地形上的风和空气污染

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90474-5

Fujio Kimura

引用次数: 3

Separation and determination of organics in air particulate matters using a new technique, low-volume liquid chromatography 用小体积液相色谱法分离测定空气颗粒物中的有机物

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90492-7

Shi-Wei Zhou ∗, Gai-Ying Ren, Shu-Yi Yu

引用次数: 2

Initial efficiencies of air cleaners for the removal of nitrogen dioxide and volatile organic compounds 空气净化器去除二氧化氮和挥发性有机化合物的初始效率

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90514-3

J.M. Daisey, A.T. Hodgson

{"title":"Initial efficiencies of air cleaners for the removal of nitrogen dioxide and volatile organic compounds","authors":"J.M. Daisey, A.T. Hodgson","doi":"10.1016/0004-6981(89)90514-3","DOIUrl":"10.1016/0004-6981(89)90514-3","url":null,"abstract":"<div>The objective of this research was to measure the initial effective cleaning rates (ECRs) of selected air cleaners for removing nitrogen dioxide (NO2) and six representative volatile organic compounds (VOC) from air. Four portable air cleaners, representing different principles of particle removal and incorporating activated carbon, were investigated. Experiments were conducted in a closed room-size environmental chamber using analyte concentrations similar to those reported in residences. Effects of relative humidity, temperature, filter particle loading and saturation of the adsorbents on the ECRs were not investigated in this preliminary study. However, the effect of extended usage was investigated for one air cleaner.Two of the air cleaners were found to be reasonably effective initially in removing NO2 and five of the six VOC. These two devices had relatively high flow rates and the greatest amounts of activated carbon. None of the devices removed dichloromethane, the VOC with the highest vapor pressure. One air cleaner emitted 1,1,1-trichloroethane and formaldehyde. After being used in a residence for 150 h, the ECRs for the air cleaner which had the highest initial values decreased to 50% or less of the initial ECRs. This use was only about 15% of the recommended filter lifetime. Conversion of NO2 to NO was also observed for this device but only after it had been used in the residence.</div>","PeriodicalId":100138,"journal":{"name":"Atmospheric Environment (1967)","volume":"23 9","pages":"Pages 1885-1892"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0004-6981(89)90514-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"52835996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

A principal component analysis of SO2−4 precipitation concentrations over the eastern United States 美国东部SO2−4降水浓度的主成分分析

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90554-4

Brian K. Eder

引用次数: 51

A note on subgrid-scale processes in photochemical modelling 光化学模拟中亚网格尺度过程的注释

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90567-2

G.D. Hess , M.E. Cope

引用次数: 7

Ozone concentrations above a Douglas-fir forest canopy in western Washington U.S.A. 美国华盛顿西部道格拉斯冷杉林冠层上方的臭氧浓度

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90011-5

Robert L. Edmonds, F.A. Basabe

{"title":"Ozone concentrations above a Douglas-fir forest canopy in western Washington U.S.A.","authors":"Robert L. Edmonds, F.A. Basabe","doi":"10.1016/0004-6981(89)90011-5","DOIUrl":"10.1016/0004-6981(89)90011-5","url":null,"abstract":"<div>Ozone concentrations were monitored above a 30 m Douglas-fir canopy at Cedar River, Washington from 1 April to 30 September in 1986 and 1987. Maximum average hourly ozone concentrations were similar in both years. Ozone concentrations exceeded 0.12 ppm on 2 days in 1986 and 1 day in 1987. Fifteen and 14 days had ozone concentrations greater than or equal to 0.08 ppm in 1986 and 1987, respectively. Ozone concentrations were positively related to daily radiation and maximum daily air temperature. However, only 46 per cent of the variance in ozone concentration in 1986 could be explained by solar radiation and even less was explained by maximum temperature (26%). In 1987, 51 and 54 per cent of the variation in ozone concentration was explained by solar radiation and temperature, respectively. Maximum average hourly ozone concentrations peaked near 1500 h (Pacific Standard Time) for days > 0.06 ppm with minimum values near 0600 h. Highest concentrations were observed when the wind was blowing from the northwest from the Seattle area indicating that photochemical oxidation of NOx was a major source of elevated ozone. If the data represent current levels of ozone some potential for forest damage exists in Puget Sound forests.</div>","PeriodicalId":100138,"journal":{"name":"Atmospheric Environment (1967)","volume":"23 3","pages":"Pages 625-629"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0004-6981(89)90011-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"52832577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14

Simulation of photochemical smog in the melbourne airshed: Worst case studies 墨尔本空气棚内光化学烟雾的模拟:最坏案例研究

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90014-0

G.D. Hess

{"title":"Simulation of photochemical smog in the melbourne airshed: Worst case studies","authors":"G.D. Hess","doi":"10.1016/0004-6981(89)90014-0","DOIUrl":"10.1016/0004-6981(89)90014-0","url":null,"abstract":"<div>The impact of a large NOx point source on photochemical smog in Melbourne is examined through the use of a numerical model described by Hess. Over most of the Melbourne Airshed the NMHC/NOx ratio is found to be less than 10, in agreement with the results of Evans et al. For these cases trajectories passing through the Newport Power Station exhibit a decrease in ozone (compared to background values) of about 0.02 ppm and an increase in nitrogen dioxide of about the same amount due to Newport's emissions. This result confirms a preliminary finding by Form and Substance (1982).However, worst case scenarios have not been previously studied. Measurements indicate that any trajectory that links the high NOx from Newport and the high NMHC from Pt Cook will result in a worst case. The windfield observations reported here show the existence of a topographically generated mesoscale eddy in the airshed, as proposed by Spillane (1978, Clean Air12, 50–56.), and its location tends to link Newport and Pt Cook. Simulation of two cases indicates that under worst case conditions Newport's emissions increase the ozone concentration by 0.01–0.04 ppm. These conditions are estimated to occur on one day in four to one day in three of high oxidant days in Melbourne.</div>","PeriodicalId":100138,"journal":{"name":"Atmospheric Environment (1967)","volume":"23 3","pages":"Pages 661-669"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0004-6981(89)90014-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"52832614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Content of quartz and mullite in some selected power-plant fly ash in Czechoslovakia 捷克斯洛伐克电厂粉煤灰中石英和莫来石的含量

Atmospheric Environment (1967) Pub Date : 1989-01-01 DOI: 10.1016/0004-6981(89)90018-8

David Havlíček, Rudolf Přibil, Bohumil Kratochvíl

{"title":"Content of quartz and mullite in some selected power-plant fly ash in Czechoslovakia","authors":"David Havlíček, Rudolf Přibil, Bohumil Kratochvíl","doi":"10.1016/0004-6981(89)90018-8","DOIUrl":"10.1016/0004-6981(89)90018-8","url":null,"abstract":"<div>This study was performed primarily to account for the differences between ice forming activity of fly ashes from different sources.Ten samples of fly ash from ten various power plants on our territory were examined by X-ray powder diffraction to determine the contents of quartz, mullite and hematite. The quartz content varied in the range 5–17% depending on the type of coal and mullite contents varied from 0 to 22%.The amounts of crystalline phases were compared with data about composition of ashes obtained by elemental chemical analysis. The distribution of silica and aluminia between crystalline phases and amorphous phase is discussed in connection with the origin of fly ash and with the differences observed in the ice forming activity. A direct relationship between the freezing temperatures and the contents of crystalline fractions in the samples does not exist but the presence of mullite and/or hematite in the concentrations found in samples could account for the observed freezing temperatures of droplets containing some of the samples.</div>","PeriodicalId":100138,"journal":{"name":"Atmospheric Environment (1967)","volume":"23 3","pages":"Pages 701-706"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0004-6981(89)90018-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"52832656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8