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601.
J. B. Maynard W. N. Sanders 《Journal of the Air & Waste Management Association (1995)》2013,63(7):505-510
The quantitative data obtained with a capillary GLC method, which is used to determine the individual C3-C12 hydrocarbons in full-range motor gasolines, have been employed in a computer program to calculate the hydrocarbon composition of the vapor in equilibrium with a gasoline at 100°F, as well as the equilibrium vapor-pressure of the gasoline at that temperature. The method used for computation is similar to that previously described by McEwen, assuming the gasoline to behave as an ideal liquid. Also calculated is the potential atmospheric reactivity of this equilibrium vapor relative to that from other gasolines when specific reactivity weighting factors for the individual hydrocarbons are employed. Calculated total vapor-pressure data agree well with experimental Reid vapor-pressure data obtained for typical premium-grade gasolines. Definite differences were observed in the relative potential atmospheric reactivities calculated at 100°F for the equilibrium vapors from the test gasolines. 相似文献
602.
J.N. Driscoll A.W. Berger J.H. Becker J.T. Funkhouser J.R. Valentine 《Journal of the Air & Waste Management Association (1995)》2013,63(2):119-122
The nitrate ion selective electrode was investigated as an alternative approach to the present colorimetric determination of nitrate resulting from oxidative absorption of nitrogen oxides from combustion effluents. The electrode offers advantages of speed and relatively simple experimental procedure. Replicate measurements of 10?4–10?2M nitric acid solutions using bracketing standards show that the electrode approach is capable of good precision (coefficient of variation = ±4%). Comparison of a method utilizing the nitrate electrode with the more laborious phenol disulfonic acid method for the measurement of nitrogen oxides in both oil and gas fired combustion effluents showed agreement within 4% of the mean even in the presence of high levels of SO2. The correlation coefficient found for PDS vs nitrate electrode is 0.987. 相似文献
603.
N.C.G. Freeman T. Wainman P.J. Lioy A.H. Stern S.I. Shupack 《Journal of the Air & Waste Management Association (1995)》2013,63(8):604-605
Honorary Memberships are conferred by the Air Pollution Control Association on persons of widely recognized eminence in some part of the field of air pollution control or who have rendered especially meritorious service to the Association. Honorary Memberships were awarded this year to Dr. Leonard Greenburg and Mr. Milton Reizenstein, both past presidents of APCA. 相似文献
604.
V.N. Finelii M. Karaffa M. Malanchuk R.M. Danner L. McMillan S.D. Lee 《Journal of the Air & Waste Management Association (1995)》2013,63(3):231-233
The introduction of oxidizing catalytic converters in the exhaust system of automobiles has been found to be effective in reducing carbon monoxide, total hydrocarbons, and some other components of tailpipe emissions. The utilization of these converters, however, has also caused further oxidation of sulfur compounds producing an increased amount of sulfur trioxide (SO3) which yields sulfuric acid and sulfates.1 Studies on the biological effects of these sulfur compounds are in progress in our laboratory and preliminary findings are reported separately. This paper compares the biological effects of exposure to whole emissions from engines with and without converter and exposure to carbon monoxide alone. 相似文献
605.
James N. Galloway Ellis B. Cowling 《Journal of the Air & Waste Management Association (1995)》2013,63(3):229-235
Precipitation is one of the most important factors determining the nature and productivity of terrestrial and aquatic ecosystems. Detailed historical and contemporary records are available indicating the amount of water deposited at thousands of locations throughout the world. Comparatively, however, knowledge of the changing chemistry of precipitation has developed only recently and is still very fragmentary. Our present ignorance of the total impact of changes in precipitation quality on the productivity and stability of ecosystems is especially profound. This paper has a fourfold purpose: (1) to describe the myriad of trace chemical constituents transferred from the atmosphere into the biosphere of the earth; (2) to define the range of beneficial and injurious ecological effects of perturbations in atmospheric deposition; (3) to explain the concepts of sensitive areas, life stages, and life forms; and (4) to describe briefly plans for a National Deposition Network and associated research on the terrestrial and aquatic ecosystems of the United States. 相似文献
606.
607.
608.
Robert N. Roop Leo Pflug Jr. 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1239-1242
The United Power Association’s dry FGD system at Stanton, North Dakota was the first utility-operated lime spray dryer to be put into service in the United States. At 60 MW in size, it utilizes a single spray dryer vessel with three rotary atomizers and a ten-compartment fabric filter. It is currently operating at better than expected efficiency and Is meeting state and federal air quality requirements. Start-up and operation have shown that certain areas of design and operating conditions are critical to reliable operation. Flue gas, slurry, and water distribution and mixing must be carefully controlled if reliable, long term operation is to be achieved. Likewise, water chemistry Is Important in the reagent preparation equipment. Start-up of the system was accomplished In a step-wise fashion to bring the baghouse on line first, followed by the spray dryer. The spray dryer was operated at gradually lower outlet temperatures until design conditions were met. Measures taken since start-up to ensure reliable operation, and operation over an eighteen month period are discussed. Both particulate and SO2 emission performance are evaluated. 相似文献
609.
耐低温贫营养好氧反硝化菌群脱氮特性及安全性 总被引:1,自引:0,他引:1
针对微污染水体强化原位生物脱氮技术同时面临低温、贫营养及好氧问题,对实验室已分离筛选的贫营养好氧反硝化菌和耐低温好氧反硝化菌进行菌源重组,构建出高效耐低温贫营养好氧脱氮功能菌群T1(Y3+F3+H8)和T2(Y3+F4)。研究不同投菌量条件下菌群的脱氮特性,结果表明,投菌量对T1脱氮效果有一定影响,0.1、0.2和1.0 mg/L投量对NO3--N去除率为71%、91%和100%,总氮去除率为56%、34%和52%;T2菌群,当投量为0.2 mg/L时,对NO3--N、总氮去除率最大可达66%和59.48%。对菌群T1、T2进行生物安全性分析,采用次氯酸钠进行消毒,其生物灭活率均达到99.9%以上。 相似文献
610.
Long-term (1860–2010) catchment mass balance calculations rely on models and assumptions which are sources of uncertainty
in acidification assessments. In this article, we report on an application of MAGIC to model acidification at the four Swedish
IM forested catchments that have been subject to differing degrees of acidification stress. Uncertainties in the modeled mass
balances were mainly associated with the deposition scenario and assumptions about sulfate adsorption and soil mass. Estimated
base cation (BC) release rates (weathering) varied in a relatively narrow range of 47–62 or 42–47 meq m−2 year−1, depending on assumptions made about soil cation exchange capacity and base saturation. By varying aluminum solubility or
introducing a dynamic weathering feedback that allowed BC release to increase at more acidic pHs, a systematic effect on predicted
changes in acid neutralizing capacity (ΔANC ca. 10–41 μeq l−1) and pH (ca. ΔpH = 0.1–0.6) at all sites was observed. More robust projections of future changes in pH and ANC are dependent
on reducing uncertainties in BC release rates, the timing, and extent of natural acidification through BC uptake by plants,
temporal changes in soil element pools, and fluxes of Al between compartments. 相似文献