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从评价指标看增量效果对总量效果的影响
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作者 韩宇才 《化工技术经济》 2004年第1期32-34,共3页
通过对净现值、内部收益率、投资利润率等指标的分析,阐述增量效果与总量效果的关系,指出决定增量效果对总量效果影响程度的因素。
关键词 评价指标 增量效果 总量效果 净现值 内部收益率 投资利润率
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技术改造项目经济评价的原理与方法 被引量:2
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作者 王丽燕 陈久云 于颖 《技术经济》 1998年第2期43-46,共4页
关键词 技改项目 项目经济评价 总量效果 技术改造 增量效果 净收益 评价法 净现值NPV 互斥方案 效果检验
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Research on optimal design of wastewater reclamation and reuse for a university
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作者 LIU Jin-song CHEN Gen-rong LIU Xin-yao ZHANG Mei-li YANG Xiu-fang 《Journal of Environmental Science and Engineering》 2009年第3期7-11,共5页
An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the tre... An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the treatment process was chosen by building a cost-benefit model; and the modeling test was performed about the operation effect of the proposed project and the recommended water quality of reclaimed water. It is estimated that 3.4×10^5 m^3/a tap water and 6.1×10^5 Yuan/a will be saved if the project was put into operation and the proposed project will reduce the total quantity of pollutant efficiently and bring lots of social and economic benefits. 展开更多
关键词 treatment process reclaimed water reuse design cost-benefit system tech-economic analysis
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Hydrologic implications of the isotopic kinetic fractionation of open-water evaporation 被引量:1
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作者 Wei XIAO Yufei QIAN +10 位作者 Xuhui LEE Wei WANG Mi ZHANG Xuefa WEN Shoudong LIU Yongbo HU Chengyu XIE Zhen ZHANG Xuesong ZHANG Xiaoyan ZHAO Fucun ZHANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第10期1523-1532,共10页
The kinetic fractionation of open-water evaporation against the stable water isotope H_2 ^(18)O is an important mechanism underlying many hydrologic studies that use ^(18)O as an isotopic tracer. A recent in-situ meas... The kinetic fractionation of open-water evaporation against the stable water isotope H_2 ^(18)O is an important mechanism underlying many hydrologic studies that use ^(18)O as an isotopic tracer. A recent in-situ measurement of the isotopic water vapor flux over a lake indicates that the kinetic effect is much weaker(kinetic factor 6.2‰) than assumed previously(kinetic factor14.2‰) by lake isotopic budget studies. This study investigates the implications of the weak kinetic effect for studies of deuterium excess-humidity relationships, regional moisture recycling, and global evapotranspiration partitioning. The results indicate that the low kinetic factor is consistent with the deuterium excess-humidity relationships observed over open oceans.The moisture recycling rate in the Great Lakes region derived from the isotopic tracer method with the low kinetic factor is a much better agreement with those from atmospheric modeling studies than if the default kinetic factor of 14.2‰ is used. The ratio of transpiration to evapotranspiration at global scale decreases from 84±9%(with the default kinetic factor) to 76±19%(with the low kinetic factor), the latter of which is in slightly better agreement with other non-isotopic partitioning results. 展开更多
关键词 Kinetic fractionation factor Craig-Gordon model Moisture recycling Evapotranspiration partitioning Deuteriumexcess
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