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991.
992.
Chan-Wei Wu Rong-Horng Chen Jen-Yung Pu Ta-Hui Lin 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):7093
Ethanol–gasoline-blended fuel was tested in a conventional engine under various air–fuel equivalence ratios (λ) for its performance and emissions. The amount of fuel injection was adjusted manually by an open-loop control system using a CONSULT controller. It was found that without changing throttle opening and injection strategy, λ could be extended to a leaner condition as ethanol content increased. The results of engine performance tests showed that torque output would increase slightly at small throttle valve opening when ethanol–gasoline-blended fuel was used. It was also shown that CO and HC emissions were reduced with the increase of ethanol content in the blended fuel, which resulted from oxygen enrichment. At an air–fuel equivalence ratio slightly larger than one, the smallest amounts of CO and HC and the largest amounts of CO2 resulted. It was noted that under the lean combustion condition, CO2 emission was controlled by air–fuel equivalence ratio; while under the rich combustion condition, CO2 emission is offset by CO emission. It was also found that CO2 emission per unit horse power output for blended fuel was similar or less than that for gasoline fuel. From the experimental data, the optimal ethanol content in the gasoline and air–fuel equivalence ratio in terms of engine performance and air pollution was found. 相似文献
993.
Akiko Furuno Hiroaki Terada Masamichi Chino Hiromi Yamazawa 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):6989
Japan Atomic Energy Research Institute has developed an emergency response system WSPEEDI to forecast long-range atmospheric dispersions of radionuclides discharged into the atmosphere. The latest version of WSPEEDI consists of an atmospheric dynamic model MM5 for calculating meteorological fields and a particle random-walk model for atmospheric dispersion. The performance of WSPEEDI was evaluated by data obtained from a field tracer experiment over Europe (ETEX) in this paper. The model validation was done with respect to the following points: (1) the dependence of model accuracy on the temporal and spatial resolutions of the meteorological fields and (2) the superiority of an atmospheric dynamic model over a mass-consistent wind model. Regarding (1), it was shown that the calculation accuracy of the new version with high temporal resolution was improved, especially at the edge of the plume. Moreover, although the increase in horizontal spatial resolution of the old version had no substantial effect on the model performance, increase in horizontal resolution of the new version contributed to the significant improvement of the calculation accuracy. These results showed that the dynamically calculated meteorological field with the spatial resolution of the meso-β–γ scale greatly improved calculation accuracy. 相似文献
994.
针对LIFAC法脱硫效率低的问题,从吸收剂的涡流循环喷钙装置、增强吸收剂的活性、抑制脱硫产物硫酸钙的高温分解等几个方面进行了剖析,并自制LIFAC法廉价喷钙剂,在佛山华丰纸业有限公司进行中试,取得了脱硫率平均90%以上的效果,最后,作者对该技术的优越性进行了评估。 相似文献
995.
Fuster G Schuhmacher M Domingo JL 《Environmental science and pollution research international》2001,8(2):91-94
The present study was intended to establish an inventory of PCDD/F emissions in Tarragona Province (Catalonia, NE Spain), as a preliminary phase in the development of a flow analysis of PCDD/Fs in this Province. In 1999, global PCDD/F emissions reached a value of 2.24 g I-TEQ/y, which means a density of 3.8 micrograms I-TEQ/inhabitant/y. The low amount of PCDD/Fs emitted to air by the only municipal solid waste incinerator in the Province (approximately 0.04% of the total) has been one of the most notable results. As a reflection of uncertainties in the estimates for individual sources, the 90th percentiles of PCDD/F releases for 1999 ranged up to 4.1 g I-TEQ/y. 相似文献
996.
农作物农药污染评价及其应用 总被引:3,自引:1,他引:3
通过对农药在作物上的消解规律和农药起始残留浓度的研究建立了农作物农药污染程度的评价方法,其评价因素选用农药起始残留浓度,农药消解速度,最后一次施药至收获的间隔期和评价标准等4个参数。应用此方法评价了常用农药以及不同类型作物的污染程度,得到了一些重要结果。 相似文献
997.
998.
Assessing environmental performance by combining life cycle assessment, multi-criteria analysis and environmental performance indicators 总被引:1,自引:0,他引:1
We present a new analytical tool, called COMPLIMENT, which can be used to provide detailed information on the overall environmental impact of a business. COMPLIMENT integrates parts of tools such as life cycle assessment, multi-criteria analysis and environmental performance indicators. It avoids disadvantages and combines complementary aspects of these three tools. The methodology is based on environmental performance indicators, expanding the scope of data collection towards a life cycle approach and including a weighting and aggregation step. A case study on the Thai pulp industry illustrates the usefulness of COMPLIMENT. 相似文献
999.
1000.
张文生 《石油化工环境保护》2000,(3):48-52
本文主要介绍双室以浮档除盐工艺应用于我厂除盐水站改造工程的设计及运行经验,说明了强、弱型树脂联合除盐工艺和双室双层浮动床的技术经济优越性,并且在实践中检验了双室双层浮动床的体内清洗技术和除盐装置的程序控制系统。 相似文献