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71.
Photovoltaic (PV) power generation has high investment costs and long payback periods. Therefore, during early deployment, subsidies are fundamental and necessary to accelerate its development. We consider the question of how to promote PV industry development and which supporting policy is more efficient in accelerating adoption. Based on real options method, we establish a subsidy efficiency model for electricity price subsidies and carbon-trading subsidies under two sources of uncertainty power demand for PV and the investment cost-reduction probability. This study aims to compare the two forms of subsidies from the perspective of promoting immediate investment and maximizing the subsidy policy efficiency for the government (minimizing the unit carbon-mitigation cost) and advance relevant policy proposals. An example of China is provided to test the effectiveness of the model and to illustrate the implications of the solutions. The results show that a carbon-trading subsidy is better than an electricity price subsidy and that it is essential to improve the demand for the power produced by the PV power-generation projects. Lower market risk and driving technology progress are both conducive to improving the subsidy efficiency. This study also provides a meaningful reference for governments worldwide to formulate subsidy programs to support PV power-generation projects.  相似文献   
72.
73.
This study investigated the level of norovirus contamination in oysters collected at a lagoon receiving urban drainage from Hue City for 17 months (August 2015–December 2016). We also investigated the genetic diversity of norovirus GI and GII in oyster and wastewater samples by using pyrosequencing to evaluate the effect of urban drainage on norovirus contamination of oysters. A total of 34 oyster samples were collected at two sampling sites (stations A and B) in a lagoon. Norovirus GI was more frequently detected than GII (positive rate 79 vs. 41%). Maximum concentrations of GI and GII were 2.4 × 105 and 2.3 × 104 copies/g, respectively. Co-contamination with GI and GII was observed in 35% of samples. Norovirus GII concentration was higher at station A in the flood season than in the dry season (P = 0.04, Wilcoxon signed-rank test). Six genotypes (GI.2, GI.3, GI.5, GII.2, GII.3, and GII.4) were identified in both wastewater and oyster samples, and genetically similar or identical sequences were obtained from the two types of samples. These observations suggest that urban drainage and seasonal flooding contribute to norovirus contamination of oysters in the study area.  相似文献   
74.
In this study, an inventory of air pollutant emission estimates from major air polluting sources in Turkey for period between 1985 and 2005 with 5-year intervals were estimated. Inventory covers anthropogenic sources of five major air pollutants of particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides and non-methane volatile organic compounds. Their break-down with respect to main activity sectors were shown and their distribution by the largest industrial source categories were worked out as annual estimates. This inventory and its analysis point to serious environmental implications of air pollutants and a need to develop a policy plan for reducing these emissions.  相似文献   
75.
采用不同形态的PHAs薄膜(聚β-羟基丁酸(PHB)及β-羟基丁酸与β-羟基戊酸的共聚物(PHBV)膜),在各种环境(如土壤和水体)的不同条件下,对膜的生物降解性进行了研究,并对其降解机制作了初步探讨。结果表明:PHAs膜具有生物降解性,在无菌条件下不能被降解;在不同的环境中,如不同土壤和水体,PHAs膜的降解情况不同;不同的条件,如pH、温度,对环境中PHAs膜的降解率有着不同的影响;PHB膜的生物降解速度比PHBV膜快;PHAs膜的厚度对其降解能力有很大影响。  相似文献   
76.
UV/H2O2光化学氧化降解对氯苯酚废水的反应动力学   总被引:9,自引:3,他引:9  
陈琳  杜瑛珣  雷乐成 《环境科学》2003,24(5):106-109
研究了UV/H2O2体系降解对氯苯酚废水的过程及动力学结果表明,反应降解速率与双氧水加入量、污染物初始浓度及载气种类有关.在双氧水理论投加量一半的情况下,通入氧气或空气,总酚的降解率可达到96%,CODCr去除率接近50%.反应体系加入载气,显著影响污染物的去除率.在本实验中,总酚降解为拟一级反应.  相似文献   
77.
用萃取法处理含苯胺废水的研究   总被引:5,自引:0,他引:5  
本文介绍了以甲苯做萃取剂萃取硫化橡胶促进剂生产废水中苯胺类物质的方法,确定了萃取级数、萃取剂配比 和萃取时间等工艺参数。经过萃取,废水中的苯胺类物质与化学需氧量的去除率分别达95%和88%以上,萃取后的废水 可以进行生化处理。  相似文献   
78.
燃烧型煤排放可吸入尘中的成分分析   总被引:1,自引:0,他引:1  
主要运用X 射线荧光光谱的半定量分析方法 ,测量了民用炉灶燃烧型煤排放的可吸入尘中的主要成分 ,从而得出在可吸入尘中的主要元素为Cl、S、Na、K ,并研究了其产生的原因  相似文献   
79.
Understanding ozone (O3) formation regime is a prerequisite in formulating an effective O3 pollution control strategy. Photochemical indicator is a simple and direct method in identifying O3 formation regimes. Most used indicators are derived from observations, whereas the role of atmospheric oxidation is not in consideration, which is the core driver of O3 formation. Thus, it may impact accuracy in signaling O3 formation regimes. In this study, an advanced three-dimensional numerical modeling system was used to investigate the relationship between atmospheric oxidation and O3 formation regimes during a long-lasting O3 exceedance event in September 2017 over the Pearl River Delta (PRD) of China. We discovered a clear relationship between atmospheric oxidative capacity and O3 formation regime. Over eastern PRD, O3 formation was mainly in a NOx-limited regime when HO2/OH ratio was higher than 11, while in a VOC-limited regime when the ratio was lower than 9.5. Over central and western PRD, an HO2/OH ratio higher than 5 and lower than 2 was indicative of NOx-limited and VOC-limited regime, respectively. Physical contribution, including horizontal transport and vertical transport, may pose uncertainties on the indication of O3 formation regime by HO2/OH ratio. In comparison with other commonly used photochemical indicators, HO2/OH ratio had the best performance in differentiating O3 formation regimes. This study highlighted the necessities in using an atmospheric oxidative capacity-based indicator to infer O3 formation regime, and underscored the importance of characterizing behaviors of radicals to gain insight in atmospheric processes leading to O3 pollution over a photochemically active region.  相似文献   
80.
本研究基于实验室筛选、培养的硫酸盐还原菌(Sulfate-reducing bacteria,简称SRB)菌群,分别考察以麦芽糊精、污泥、乙醇、乳酸钠等为碳源时SRB的生长状况,同时模拟野外环境进行柱淋滤实验,分析在不同碳源作用下原位控制酸性矿山废水的效果.结果表明,采用这4种碳源时,SRB还原硫酸盐能力的大小依次为:...  相似文献   
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