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111.
本文利用1979—1981年气象资料用统计方法分析了城市热岛效应对主要气象要素时空分布特征的影响(例如:温度、无霜期、风速、日照、云量、降水量、雷暴、雨日、雾日和土壤温度),结果表明:城市效应对市区大气环境的影响是明显的。 相似文献
112.
M. W. Kress R. Baker S. J. Ursic 《Journal of the American Water Resources Association》1990,26(5):747-756
ABSTRACT: The deposition and chemistry of precipitation were estimated for one year in two forest ecosystems in the South-Central United States. Precipitation, throughfall, litter leachate, and soil leachate were analyzed for a small catchment of pine-hardwoods in southeastern Oklahoma and for a catchment of loblolly pines (Pinus taeda L.) in northern Mississippi. In the pine-hardwood forest, 98 percent of the acid deposition was neutralized, 50 percent in the forest canopy, and 48 percent in the forest floor. In the pine forest, 75 percent of the acid deposition was neutralized, all in the forest floor. The pine-hardwood ecosystem accumulated sulfate, nitrate, and ammonia ions, and lost base cations. During seasons of deficient precipitation, dry deposition appeared to enrich the concentrations of hydrogen, nitrate, sulfate, and ammonia ions in throughfall samples at both locations. 相似文献
113.
对油炉法炭黑生产过程烟气的来源,组成,发生量,特性作了介绍,着重研究了炭黑烟气余热的加收及利用。结果表明,采用余热锅炉串联多级空气预热器,是目前我国炭黑烟气余热回收及利用的最佳方法,采用这种方法,不仅可将高温炭黑烟气的余热量最大限度地回收及利用,同时可满足炭黑收集及烟气净化系统设备对炭黑烟气温度的要求,采用该法,炭黑烟气余热利用率可提高20%以上,经济效益十分可观。 相似文献
114.
韶钢新石灰窑烟气除尘系统要用旋风除尘器、金属管式换热器、高效陶瓷多管除尘器的组合方式。介绍了该系统的设计参数、工艺流程、主要设备及其功能。 相似文献
115.
116.
本文通过采用催化法和直燃法两种工艺处理印铁涂装生产的有机废气的工业实践,对设计和运行中的一些要点进行分析和探讨。 相似文献
117.
118.
Ahmed I. El-Seesy Mohamed Nour Ali M. A. Attia Hamdy Hassan 《International Journal of Green Energy》2020,17(3):233-253
ABSTRACTThis article aims to study the influence of the addition of graphene oxide nanoparticles (GO) to diesel/higher alcohols blends on the combustion, emission, and exergy parameters of a CI engine under various engine loads. The higher alcohols mainly n-butanol, n-heptanol, and n-octanol are blended with diesel at a volume fraction of 50%. Then, the 25 and 50 mg/L concentrations of GO are dispersed into diesel/higher alcohols blends using an ultrasonicator. The GO structures are examined using TEM, TGA, XRD and FTIR. The findings show that there is a reduction in pmax. and HRR when adding higher alcohols with diesel fuel. Regarding engine emission, there is a significant improvement in emissions formation with adding higher alcohols. The addition of GO into diesel/higher alcohols blends improves the brake thermal efficiency by 15%. Moreover, the pmax. and HRR are both enhanced by 4%. The CO, UHC and smoke formation are reduced considerably by 40%, 50 and 20%, respectively, while NOx level is increased by 30% with adding GO. Finally, adding high percentages of n-butanol, n-heptanol, and n-octanol with diesel fuel with the presence of GO has the potential to achieve ultra-low CO, UHC, and smoke formation meanwhile keeping high thermal efficiency level. 相似文献
119.
Altamash Ahmad Baig Farshad Kimiaghalam Rakesh Kumar JuanLi Ma Alan S. Fung 《International Journal of Green Energy》2020,17(8):476-487
ABSTRACT An eQUEST model was developed to conduct a simulation study of a natural gas engine-driven heat pump (GEHP) for an office building in Woodstock, Ontario, Canada. Prior to the installation of the GEHP, the heating and cooling demands of the office building were provided by rooftop units (RTUs), comprising of natural gas heater and electric air conditioner. Energy consumption for both GEHP and RTUs were monitored for operation in alternating months. These recorded energy consumptions along with weather data were used in the regression analysis. The developed eQUEST models were validated and calibrated with the regression analysis results with respect to the ASHRAE Guideline 14–2014. The eventual models were then applied to investigate the potential annual energy consumption, greenhouse gas (GHG) emission and energy cost savings achieved by using the GEHP in Woodstock, and other cities in Canada, particularly in Ontario. 相似文献
120.
Hiroshi Mitomo Kazunobu Sasada Kenji Nishimura Fumio Yoshii Naotsugu Nagasawa 《Journal of Polymers and the Environment》2004,12(2):95-103
Poly(-caprolactone) (PCL) was blended with diatomaceous earth (diatomite) and irradiated with -rays to introduce cross-linking between PCL molecules or both components. The unwashed diatomite containing a little of a volatile component showed high efficiency of introduction of cross-linking, whereas that with no volatile component showed low efficiency of introduction of cross-linking. Elongational viscosity, melt viscosity, and modulus of PCL/diatomite blend irradiated at various doses were significantly improved. Enzymatic degradation of the PCL/diatomite blend became faster than that of the PCL, though that of the blend irradiated became slower. 相似文献