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981.
Source resolution and risk apportionment of emission source categories for risk reduction purposes can be used to enhance
the Bubble Policy of the Clean Air Act. This is performed by incorporating receptor modeling techniques of factor analysis
and chemical mass balances to assess noncarcinogenic and carcinogenic inhalation risks to a target population for certain
pollutants coming from major emission source categories in a steel plant air shed. Source resolution, using factor analysis,
statistically interprets a “source” from ambient data. By subsequently quantifying risks from identified metal emission sources
using chemical mass balances and risk apportionment, a total additive risk from main source contributors in the steel plant
is estimated. From this methodology, the Bubble Policy can be enhanced by targeting only main risk sources or by “risk-trading”
with minor impact sources to reduce the total risk (if deemed significant) without arbitrarily reducing risk for all sources
in an industrial source complex’s “bubble.” 相似文献
982.
活性碳纤维(PAN—ACF)对SO2的物理吸附、传质机理和扩散的探讨 总被引:6,自引:0,他引:6
本文研究PAN-ACF的主要结构参数,探讨了ACF对SO2的物理吸附、脱附性能以及传质机理,得出传质过程为内扩散控制,并计算出扩散系数D值约为活性炭D的50-170倍。 相似文献
983.
Ronald B. Zelt Jack T. Dugan 《Journal of the American Water Resources Association》1993,29(6):939-948
ABSTRACT: Soil-water conditions provide valuable insight into the hydrologic system in an area. A soil-water balance quantitatively summarizes soil-water conditions and is based on climatic, soil, and vegetation characteristics that vary spatially and temporally. Soil-water balances in the Great Plains of the central United States were simulated for 1951–1980. Results of the simulations were mean annual estimates of infiltration, runoff, actual evapotranspiration, potential recharge, and consumptive water and irrigation requirements at 152 climatic data stations. A method was developed using a geographic information system to integrate and map the simulation results on the basis of spatially variable climatic, soil, and vegetation characteristics. As an example, simulated mean annual potential recharge was mapped. Mean annual potential-recharge rates ranged from less than 0.5 inch in much of the north-central and southwestern Great Plains to more than 10 inches in parts of eastern Texas and southwestern Arkansas. 相似文献
984.
Paolo Leonelli Carlo Stramigioli Gigliola Spadoni 《Journal of Loss Prevention in the Process Industries》1994,7(6):443-450
This paper describes a mathematical model which calculates the time dependencies of the flow rate and composition of the vapour emerging from a pool. A large variety of accidental cases can be covered: continuous or instantaneous spills, on confined or unconfined ground, ideal or non-ideal liquid mixtures in boiling or evaporating conditions. The boiling, when present, is modelled through an equation system comprising the Rachford-Rice relation and the energy balance of the pool, which is assumed to be well-mixed. In the case of a volatile pool, interfacial mass rates are determined taking into account the Stefan flux, and the thermal resistance inside the liquid phase is also considered. In all situations, the energy balance includes the contribution of ground, sun and air. Known experimental data have been used to validate the model. 相似文献
985.
Leo M. Eisel Kimberly D. Mills Charles F. Leaf 《Journal of the American Water Resources Association》1988,24(4):815-820
ABSTRACT: Consumptive loss of water attributable to man-made snowmaking was estimated using an energy balance model and a mass balance procedure. Data from nine field experiments at Colorado ski areas were collected and used in these models. The mean consumptive loss using the energy balance model for the nine experiments was 6.0 percent and 5.8 percent for the mass balance model A thermodynamic relationship and a regression equation were developed to provide a procedure to estimate consumptive loss as a linear function of atmospheric temperature. 相似文献
986.
Dennis Nullet 《Journal of the American Water Resources Association》1987,23(6):1125-1132
ABSTRACT: This study presents an estimate of water balance components for Pacific atolls under average dimatological conditions. Figures show annual potential evapotranspiration, annual recharge for rain-fed and aquifer-fed vegetated areas, and the number of months that potential evapotranspiration exceeds actual evapotranspiration (indicating water stress) under average conditions. The method relies on the assumption that small islands have minimal influence on cloudiness and precipitation. The potential evapotranspiration is computed using the equilibrium evaporation concept, and estimates of monthly soil water storage and recharge follow Thornthwaite's bookkeeping method. Gradients in potential evapotranspiration run primarily north-south, though for the equatorial zone potential evapotranspiration declines from east to west, opposing the trend in rainfall. Recharge estimates range from 250 mm in the central Tuamotu Archipelago and zero in eastern Kiribati to over 2000 mm per year in the southern Caroline Islands (U.S. Trust Territory) and Solomon Islands. The sensitivity of the model to intra-month rainfall variability and a range of available soil moisture values is discussed. 相似文献
987.
William G. Guthe M. L. Shelton 《Journal of the American Water Resources Association》1987,23(5):767-775
ABSTRACT: Competition for water, concerns for maintaining ground water quality, and compliance with legislative action require quantification of the water resource for high elevation watersheds in the Sierra Nevada. However, meager hydroclimatic data frequently hinder runoff assessments needed for formulating water development policies, and the selection of watershed models for estimating the water resource is limited to those requiring a minimum of observational data. A climatic water budget model and an energy slope and aspect model are employed to estimate the water resource for a small watershed in Sierra Valley north of Lake Tahoe. The models employ different assumptions and computational procedures, but the total water available estimated by both models is very similar. Measured runoff is estimated satisfactorily by the models, but streamflow is not representative of the total water resource because a substantial portion of the available water enters the regional ground water system. This conclusion is supported by hydrologic and geochemical evidence, and ground water recharge is estimated to be at least as great as measured runoff during dry years and nearly twice as large during wet years. 相似文献
988.
蚯蚓有机废水土地处理试验研究 总被引:4,自引:0,他引:4
利用蚯蚓的有机废水土地处理是一种符合生态平衡的新的处理技术,在这种处理工艺中,含有蚯蚓的土壤对废水中的COD的吸附去除百分数和有机物负荷均比常规的污水土地处理高两倍以上。这一处理过程的机理符合吸附,再生过程的一级反应动力学。 相似文献
989.
990.
杨学亮 《中国环境管理干部学院学报》2007,17(1):56-58,64
地价与房价作为房地产市场的两个重要指标,其水平高低对房地产市场的正常、有序发展起者重要作用。房价与地价在一定范围内、一定条件下相互作用,相互影响。正确分析和处理房价与地价的关系,促进房地产业健康发展,可采取以下措施:土地交易信息公开、透明;土地及时开发,及时入市;加强对土地市场供需结构的宏观调控和经济适用房、廉租房体系的建设等。 相似文献