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961.
考虑到企业和消费者的低碳策略往往受到政府补贴政策的影响,构建了消费者、消费领域相关企业和政府的三方演化博弈模型,探讨多种因素对各主体策略选择的影响机制.研究表明:企业低碳生产的概率与政府补贴力度、消费者低碳偏好、放弃低碳生产的机会成本和市场损失正相关,与生产方式转变成本负相关;消费者低碳消费的概率与政府补贴力度、低碳偏... 相似文献
962.
城市绿地是城市生态系统的重要组成部分,在改善城市生态系统方面有重要作用。现今交通是城市环境中的主要噪声来源,城市道路绿地是交通噪声治理的有效方式之一。本文选取杭州市西湖区不同等级的三条道路(紫金港路、天目山路和丰潭路)作为研究对象,利用手持噪声测量仪测量实时噪声对不同道路等级和距离的绿地降噪效果进行分析。研究发现,杭州市三条道路存在以下问题:(1)噪声距离道路越远越低,且噪声平均衰减率表明绿地降噪效果为主干道次干道快速路;(2)配置模式为乔木+灌木+地被的绿地植物群落的降噪效果最佳,且乔木和灌木交错的种植形式在降噪效果上优于灌木在前、乔木在后的排列式种植;(3)当道路绿地宽达到15m时,植物群落降噪效果会有大幅度提升,且快速路与次干道在距离为15m处,植物群落降噪能力最佳。 相似文献
963.
964.
OECD国家经验对我国排污收费制度的启示 总被引:2,自引:0,他引:2
我国现行排污收费制度虽发挥了筹集污染治理经费的功能,但未能达到促进污染物减排的功效。针对这一问题,借鉴OECD国家经验,提出国内应将排污收费标准提高至不低于治理成本;同时需根据成本的有效性确定收费对象。 相似文献
965.
冯爱 《中国环境管理干部学院学报》2009,19(2):92-94
基于经济和社会等方面的原因,土地所有权的价格一般会不断上涨,固定年期土地使用权价格也会随之上升。但受让土地使用权价格存在类似折旧的现象。投资人能否从地价普遍上涨中获得增值收益,取决于土地所有权增值比率、土地还原利率、剩余使用年期等多种因素。 相似文献
966.
Detlef Hinneburg Eberhard Renner Ralf Wolke 《Environmental science and pollution research international》2009,16(1):25-35
Background, aim, and scope The fraction of ambient PM10 that is due to the formation of secondary inorganic particulate sulfate and nitrate from the emissions of two large, brown-coal-fired
power stations in Saxony (East Germany) is examined. The power stations are equipped with natural-draft cooling towers. The
flue gases are directly piped into the cooling towers, thereby receiving an additionally intensified uplift. The exhausted
gas-steam mixture contains the gases CO, CO2, NO, NO2, and SO2, the directly emitted primary particles, and additionally, an excess of ‘free’ sulfate ions in water solution, which, after
the desulfurization steps, remain non-neutralized by cations. The precursor gases NO2 and SO2 are capable of forming nitric and sulfuric acid by several pathways. The acids can be neutralized by ammonia and generate
secondary particulate matter by heterogeneous condensation on preexisting particles.
Materials and methods The simulations are performed by a nested and multi-scale application of the online-coupled model system LM-MUSCAT. The Local
Model (LM; recently renamed as COSMO) of the German Weather Service performs the meteorological processes, while the Multi-scale
Atmospheric Transport Model (MUSCAT) includes the transport, the gas phase chemistry, as well as the aerosol chemistry (thermodynamic
ammonium–sulfate–nitrate–water system). The highest horizontal resolution in the inner region of Saxony is 0.7 km. One summer
and one winter episode, each realizing 5 weeks of the year 2002, are simulated twice, with the cooling tower emissions switched
on and off, respectively. This procedure serves to identify the direct and indirect influences of the single plumes on the
formation and distribution of the secondary inorganic aerosols.
Results and conclusions Surface traces of the individual tower plumes can be located and distinguished, especially in the well-mixed boundary layer
in daytime. At night, the plumes are decoupled from the surface. In no case does the resulting contribution of the cooling
tower emissions to PM10 significantly exceed 15 μgm−3 at the surface. These extreme values are obtained in narrow plumes on intensive summer conditions, whereas different situations
with lower turbulence (night, winter) remain below this value. About 90% of the PM10 concentrations in the plumes are secondarily formed sulfate, mainly ammonium sulfate, and about 10% originate from the primarily
emitted particles. Under the assumptions made, ammonium nitrate plays a rather marginal role.
Recommendations and perspectives The analyzed results depend on the specific emission data of power plants with flue gas emissions piped through the cooling
towers. The emitted fraction of ‘free’ sulfate ions remaining in excess after the desulfurization steps plays an important
role at the formation of secondary aerosols and therefore has to be measured carefully. 相似文献
967.
CO_2 Emissions Embodied in China-U.S.Trade 总被引:1,自引:0,他引:1
After the Kyoto Protocol was implemented, carbon leakage exerts great influences on international trade and economy. Trade creates a mechanism for consumers to shift environmental pollution associated with their consumption to other countries. China has overtaken the U.S. as the world's biggest CO2 emitter since 2006. As China's second largest trade partner, the U.S. has the biggest trade deficit with China which has aroused a lot of disputes between the two parties. But so far the assessments of the trade imbalance of China-U.S. have paid little attention to environmental impacts associated with the trade imbalance. Applied an input-output approach, the article estimates the amount of CO2 embodied in China-U.S. trade during 1997-2007. It was found that through trade with China, the U.S. reduced its CO2 emissions compared with a non-trade scenario. Due to the greater carbon-intensity and relatively less efficient production processes of Chinese industry, China-U.S. trade resulted in more CO2 emissions in China and the world. In the end, the article gives some suggestions: it is equal and sustainable that the international accounting methodologies should be improved, for CO2 emissions responsibility must be designed to account for the dynamic nature of international trade. 相似文献
968.
M. El-Fadel L. Abi-Esber T. Ayash 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5015-5026
The use of regulatory and compliance-based modeling for air quality impact assessment is invariably relied upon to predict future air quality under various management scenarios particularly where air quality monitoring data are limited. This paper examines the dispersion from a multi-stack cement manufacturing complex with associated quarries and transport activities for regulatory compliance under uncertain emission and meteorological conditions. The concentrations of CO, NOx, SO2 and PM at sensitive receptor locations were used as indicators in comparison to World Health Organization (WHO) interim guidelines. Exceedance exposure areas were delineated under bounded uncertainties in input emission factors and meteorological parameters. Planning and management initiatives were tested to control/minimize potential exposure. Compared to the case of low emissions and actual meteorological conditions, the consideration of worst emissions coupled to worst meteorological conditions enlarged the boundaries of the exceedance exposure areas considerably. The implementation of best available technologies and enforcement of emission standards improved air quality in the region significantly and lowered the exposure at many population centers to below health standards. Uncertainty in the output of atmospheric dispersion models continues to play a significant role to be considered at the point where science is translated into political decision making. 相似文献
969.
C.S. Cheung Lei Zhu Zhen Huang 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):4865-4872
Experiments were carried out on a diesel engine operating on Euro V diesel fuel, pure biodiesel and biodiesel blended with methanol. The blended fuels contain 5%, 10% and 15% by volume of methanol. Experiments were conducted under five engine loads at a steady speed of 1800 rev min−1 to assess the performance and the emissions of the engine associated with the application of the different fuels. The results indicate an increase of brake specific fuel consumption and brake thermal efficiency when the diesel engine was operated with biodiesel and the blended fuels, compared with the diesel fuel. The blended fuels could lead to higher CO and HC emissions than biodiesel, higher CO emission but lower HC emission than the diesel fuel. There are simultaneous reductions of NOx and PM to a level below those of the diesel fuel. Regarding the unregulated emissions, compared with the diesel fuel, the blended fuels generate higher formaldehyde, acetaldehyde and unburned methanol emissions, lower 1,3-butadiene and benzene emissions, while the toluene and xylene emissions not significantly different. 相似文献
970.
Yan Zhang Donghui Chen Liang Chen Stephanie Ashbolt 《Journal of environmental management》2009,91(1):222-226
Rainwater is a traditional but underutilized water resource that has today had a resurgence due to the worldwide water crisis. This paper demonstrates the outcomes of research on the feasibility of rainwater use in high-rise residential envelopes for four Australian cities of Melbourne, Sydney, Perth and Darwin. Different climate patterns and various levels of water demand management were established for determination of storage dimensions; annual tank water use; reduction in both imported water flow and stormwater disposal; and water spillage from tanks. High level water demand management was a profoundly effective tool for reducing potable water supply, especially in combination with rainwater use. The economic feasibility of rainwater use systems were estimated; with Sydney having the shortest payback period compared to other cities either both with 3A rated appliances (8.6 years) or 5A ones installed (10.4 years). That was due to the higher and more consistent rainfall in Sydney. An outcome of this study was that Sydney was likely most suited to rainwater use, followed by Perth, Darwin, and then Melbourne. The objective of this study was to fill in the gap in estimating feasibility of rainwater use in various Australian cities. This investigation endeavors to provide assistance to water authorities and urban planners of Australian cities with the consideration of the potential of rainwater harvesting. 相似文献