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211.
In terms of today, one may argue, throughout observations from energy literature papers, that (i) one of the main contributors of the global warming is carbon dioxide emissions, (ii) the fossil fuel energy usage greatly contributes to the carbon dioxide emissions, and (iii) the simulations from energy models attract the attention of policy makers to renewable energy as alternative energy source to mitigate the carbon dioxide emissions. Although there appears to be intensive renewable energy works in the related literature regarding renewables’ efficiency/impact on environmental quality, a researcher might still need to follow further studies to review the significance of renewables in the environment since (i) the existing seminal papers employ time series models and/or panel data models or some other statistical observation to detect the role of renewables in the environment and (ii) existing papers consider mostly aggregated renewable energy source rather than examining the major component(s) of aggregated renewables. This paper attempted to examine clearly the impact of biomass on carbon dioxide emissions in detail through time series and frequency analyses. Hence, the paper follows wavelet coherence analyses. The data covers the US monthly observations ranging from 1984:1 to 2015 for the variables of total energy carbon dioxide emissions, biomass energy consumption, coal consumption, petroleum consumption, and natural gas consumption. The paper thus, throughout wavelet coherence and wavelet partial coherence analyses, observes frequency properties as well as time series properties of relevant variables to reveal the possible significant influence of biomass usage on the emissions in the USA in both the short-term and the long-term cycles. The paper also reveals, finally, that the biomass consumption mitigates CO2 emissions in the long run cycles after the year 2005 in the USA.  相似文献   
212.
In order to examine whether the leaves of the Colorado blue spruce (Picea pungens) are damaged or not by traffic pollution, the traits of the anatomy and physiology of its leaves are investigated by exposure to vehicle exhausts in a laboratory experiment lasting 30 days. The results show that both the anatomical structures and physiological traits of the leaves are significantly affected by vehicle exhausts. The anatomical structures, including epidermis, cuticle, palisade, and spongy parenchyma are modified when exposed to the high concentrations (≥0.4 mg/m3) of vehicle exhausts. However, physiological traits such as total chlorophyll content are not changed when exposed to different concentrations of vehicle exhaust. Unlike the total chlorophyll content, the electrical conductivities increased, whereas the POD activities decreased when presented in vehicle exhausts. The present study indicates that the Colorado blue spruce changes its anatomical structures and physiological traits to avoid possible damage by vehicle exhausts.  相似文献   
213.
为了深入认识石油烃的厌氧降解过程,利用分子生物学技术分析了大庆油田采油废水处理系统厌氧池和进水中的微生物群落特征。基于DGGE和克隆文库的分析结果均表明,厌氧生物膜中存在的古菌源自于采油废水。厌氧生物膜和采油废水中的古菌主要是产甲烷菌,包括嗜甲基的Methanomethylovorans thermophila和利用氢和甲酸的Methanolinea tarda。值得注意的是,氢营养型的M.tarda在厌氧生物膜中得到了富集。进水和厌氧生物膜中的细菌群落结构明显不同。进水中的主要细菌类群为Epsilonproteobacteria,而生物膜中的主要类群为Nitrospira和Deltaproteobacteria。在厌氧生物膜中发现许多与产甲烷古菌(尤其是氢营养型产甲烷菌)协同降解石油烃类物质的细菌相关克隆:其中一个克隆与Syntrophus具有较高的同源性,该类菌是产甲烷菌介导的厌氧烃降解微生物区系中的关键细菌;许多Deltaproteobacteria克隆属于group TA类群,该类群细菌主要参与芳香族化合物产甲烷菌介导的厌氧降解过程。这些结果表明,在大庆油田采油废水厌氧处理系统中已经建立起由产甲烷菌所介导的厌氧石油烃降解的微生物区系。  相似文献   
214.
215.
污染源在线监测系统的应用是环境执法、科学管理的重要手段。概述了大港油田区域在线监测系统建设现状及管理现状。分析管理中发现的典型问题,提出应对措施。针对实时数据与COD实测数据偏差较大,提出通过计算显示值与数采仪数据之差,手动调节在线监测仪的输出电流,从而有效降低数据传输偏差;针对COD在线监测仪受氯离子干扰而导致数据异常现象,从三方面提出解决办法:强化对前段来液的处理水平,适当增加掩蔽剂的投入量,选择更加适合的在线监测方法。  相似文献   
216.
A pipe rupture during unloading led to a spillage of 350-700 tonnes of Ca?o Limon, a light sweet crude oil, into San Vicente Bay in 2007. Initial clean-up methods removed the majority of the oil from the sandy beaches although some oil remained on the rocky shores. It was necessary for the responsible party to clean the spilled oil even though at this location there were already crude oil hydrocarbons from previous industrial activity. A biosolvent based on vegetable oil derivatives was used to solubilise the remaining oil and a statistical approach to source apportionment was used to determine the efficacy of the cleaning. Sediment and contaminated rock samples were taken prior to cleaning and again at the same locations two days after application of the biosolvent. The oil was extracted using a modified USEPA Method 3550B. The alkanes were quantified together with oil biomarkers on a GC-MS. The contribution that Ca?o Limon made to the total oil hydrocarbons was calculated from a Partial Least Squares (PLS) analysis using Ca?o Limon crude oil as the source. By the time the biosolvent was applied, there had already been some attenuation of the oil with all alkanes 相似文献   
217.
建立了车载顶空-气相色谱质谱法(GC/MS)测定水中22种挥发性有机物(VOCs)的方法,顶空平衡温度和平衡时间的最优设置分别为80℃和30 min。该方法各目标化合物分离良好,在目标化合物质量浓度5~100μg/L范围内,线性良好,相关系数均0.995,方法的检出限为1.16~2.88μg/L,RSD为7.71%~26.5%,加标回收率为52.3%~129%,能够满足应急监测工作的需要。  相似文献   
218.
以水解法制备的锐钛矿型TiO2为载体,制备了CuO/TiO2型光催化剂.以亚甲基蓝为对象,在可见光照射下研究了H2O3加入量、pH值和催化剂投加量对脱色效果的影响,同时与改性前的TiO2催化剂进行了脱色效果的对比.结果表明亚甲基蓝在碱性条件下能较好脱色,H2O2用量和CuO/TiO2催化剂投加量分别为每1 000 mL反应液各加入10 mL和0.1 g时脱色最好;另外,TiO2催化剂也在碱性条件下能较好脱色,H2O2用量和催化剂投加量分别为每1 000 mL反应液各加入12.5 mL和0.1 g时脱色最好.最优条件下对比实验表明,CuO/TiO2型催化剂在可见光照射下具有很高的催化活性,亚甲基蓝2 h脱色率达到88%,远好于改性前的TiO2和Degussa P25催化剂.  相似文献   
219.
着重介绍在球团竖炉电除尘器电气控制中的PLC应用,以及利用矩阵控制原理对PLC输出接口的扩展,详细介绍高、低压电气控制系统主要实现的功能和特点。  相似文献   
220.
Hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites were selected for elemental mercury(Hg~0) removal from non-ferrous metal smelting flue gas in this study. Results showed that the hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites had favorable Hg~0 removal ability at low temperature. Moreover, the adsorption capacity of hierarchical magnetic composite is much larger than that of pure Fe_3O_4 and SiO_2@Fe_3O_4. The Hg~0 removal efficiency reached the highest value as approximately 92% under the reaction temperature of 150°C, while the removal efficiency sharply reduced in the absence of O_2. The characterization results indicated that Ag nanoparticles grew on the surface of SiO_2@Fe_3O_4 support. The large surface area of SiO_2 supplied efficient reaction room for Hg and Ag atoms. Ag–Hg amalgam is generated on the surface of the composites. In addition, this magnetic material could be easily separated from fly ashes when adopted for treating real flue gas, and the spent materials could be regenerated using a simple thermal-desorption method.  相似文献   
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