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LevelofcoordinateddevelopmentineconomyandenvironmentZhangQide,WangYuxiu,RenJinsongLiaoningInstituteofEnvironmentProtectionSci... 相似文献
97.
A result that application of sodium selenite or fly ash to some of soilin loess plateau can increase Se content in wheat grain has been demonstrated by the pot and field experiments, and added Se in soil can last its availability for 3 years. So this is a good measure for improving the low Se soils and preventing the Kaschin-Beck disease. 相似文献
98.
任于翎 《辽宁城乡环境科技》2004,24(5):41-43,46
通过对顺城河北地区地表水环境现状特点及其污染状况的调查详细分析了各支流的纳污量,了解河北地区各支流对浑河主河道的“污染贡献”,运用科学的方法确定各功能水质目标,提出水污染总量、控制削减方案和治理方案。 相似文献
99.
Effect of leachate recycling and inoculation on the biochemical characteristics of municipal refuse in landfill bioreactors 总被引:2,自引:0,他引:2
Activity development of key groups of enzymes involved in municipal refuse decomposition was measured in laboratory landfill bioreactors with and without leachate recycling and inoculation for about 210 days.The results showed that the enzymes(amylase,protease,cellulase,lipase and pectinase)were present in fresh refuse but at low values and positively affected by leachate recycling and refuse inoculation.The total average of cellulase activity in digesters D3 operated with leachate recycling but no inoculation,D4 and D5 operated with leachate recyling and inoculation was much higher than that in digesters D1 and D2 without leachate recycling and inoculation by 88%-127%,117%-162%and 64%-98%.The total average of protease activity was higher in digester D4 than that in digesters D1,D2,D3and D5 by 63%,39%,24%and 24%,respectively,and the positive effect of leachate recycling and inoculation on protease activity of landfilled refuse mainly was at the first two months.The total average of amylase activity was higher in digesters D3,D4 and D5 than that in digesters D1 and D2 by 83%-132%,96%-148%and 81%-129%.During the early phase of incubation,the stimulatory effect of inoculation on lipase activity was measured,but refuse moisture was the main factor affecting lipase activity of landfilled refuse.The inoculation,initial and continuous inoculation of microorganisms existing in leachate,was the mainly stimulatory factor affecting pectinase activity of landfilled refuse. 相似文献
100.
Wu Rui Li Guangyi Zhang Zongyi Ren Yulong Han Weijian 《Frontiers of Environmental Science & Engineering in China》2007,1(3):292-298
Road transport produces significant amounts of emissions by using crude oil as the primary energy source. A reduction of emissions
can be achieved by implementing alternative fuel chains. The objective of this study is to carry out an economic, environmental
and energy (EEE) life cycle study on natural gas-based automotive fuels with conventional gasoline in an abundant region of
China. A set of indices of four fuels/vehicle systems on the basis of life cycle are assessed in terms of impact of EEE, in
which natural gas produces compressed natural gas (CNG), methanol, dimethylether (DME) and Fischer Tropsch diesel (FTD). The
study included fuel production, vehicle production, vehicle operation, infrastructure and vehicle end of life as a system
for each fuel/vehicle system. A generic gasoline fueled car is used as a baseline. Data have been reviewed and modified based
on the best knowledge available to Chongqing local sources. Results indicated that when we could not change electric and hydrogen
fuel cell vehicles into commercial vehicles on a large scale, direct use of CNG in a dedicated or bi-fuel vehicle is an economical
choice for the region which is most energy efficient and more environmental friendly. The study can be used to support decisions
on how natural gas resources can best be utilized as a fuel/energy resource for automobiles, and what issues need to be resolved
in Chongqing. The models and approaches for this study can be applied to other regions of China as long as all the assumptions
are well defined and modified to find a substitute automotive energy source and establish an energy policy in a specific region. 相似文献