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991.
选取衡阳市区和衡山背景站臭氧自动监测数据,分析两地的臭氧污染特征。对空气质量的优良率情况、臭氧作为首要污染物的变化情况、臭氧浓度的日变化特征、典型时段的浓度变化特征、臭氧浓度的月际变化特征和臭氧与PM_(2.5)的关联情况等进行了分析。结果表明,多云及阴雨天气时,衡阳市区的臭氧浓度日变化幅度大于衡山背景站。夏季,衡阳市区和衡山背景站的臭氧浓度的日变化特征规律差异较大,臭氧浓度分布比较分散,前者为典型的单峰形,后者则波动平缓。冬季,日变化幅度不大,但衡阳市区的臭氧浓度明显低于衡山背景站。衡山背景站和衡阳市区的臭氧基本同步变化,但日均值高于衡阳市区。  相似文献   
992.
ABSTRACT

Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature. This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China’s peripheral areas utilizing the panel data of 218 cities in China. Making use of indicators for measuring the impact on environmental pollution, it identifies that environmental pollution between cities of China has a significant two-way spillover effect. After standardization of variables, it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected. Nearly, a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas. If the indicator of environmental pollution in peripheral areas is missing, wrong conclusions will be drawn. Therefore, government should shift the emphasis of environmental regulation from local to global, and improve the overall environmental quality through coordinated management of regional environment.  相似文献   
993.
ABSTRACT

This paper assesses the evolution of generation technology-mix in Australia, with specific emphasis on understanding how such evolution has been shaped by wider political and socio-economic influences. This assessment is predicated on the argument that the contemporary, quintessentially techno-economic, policy discourse on renewable energy is deficient, as it ignores climacteric political and socio-economic influences on generation technology-mix. The methodological framework employed in this paper is informed by the core tenets of technological change theory. The assessment suggests that generation technology-mix in Australia has historically been overwhelmingly influenced by the underlying technological paradigm of the electricity industry; and that this technological paradigm essentially draws its imprimatur from the wider political and socio-economic contexts. By implication, it suggests that a rapid uptake of renewables will have widespread ramifications, extending into political, socio-economic and cultural realms of a society. Clearly, existing policy discourse – that tends to focus on technical potentials, cost competitiveness, externalities and risks of various renewable technologies – is deficient. A much broader discourse is needed. This paper also made an attempt to develop a basis for such a discourse by reviewing broader aspects of the Australian society that would be affected by a rapid uptake of renewables.  相似文献   
994.
以赤水河流域为研究对象,根据Landsat8 OLI卫星影像获取流域土地利用现状,利用ArcGIS的水文、空间分析模块提取22个子流域,分析子流域不同形态氮(TN、NO_3~--N、NH_4~+-N)的输出特征及其与土地利用结构之间的关系。结果表明:赤水河各子流域TN、NO_3~--N、NH_4~+-N浓度范围分别为1. 27~4. 13、1. 14~3. 97、0. 01~0. 35 mg/L。TN和NO_3~--N与流域内耕地、灌草的相关系数分别为0. 663 (p 0. 01)、0. 538 (p 0. 05)和0. 631(p0. 01)、0. 530(p0. 05),TN、NO_3~--N、NH_4~+-N与流域内耕地、灌草浓度表现为显著正相关,流域内耕地、灌草对TN、NO_3~--N输出均表现为显著的"氮源"作用。NH_4~+-N的相关系数为-0. 558(p 0. 01),耕地对NH_4~+-N输出起显著"氮汇"作用。TN、 NO_3~--N与林地的相关系数为-0. 673 (p 0. 01)、-0. 652(p0. 01),林地对TN、NO_3~--N输出起到了显著的"氮汇"作用。NH_4~+-N与林地的相关系数为0. 435(p0. 05),林地对NH_4~+-N的输出起"氮源"作用。各子流域的分析结果表明,流域受土地利用结构带来的面源污染影响显著。  相似文献   
995.
农户的亲环境行为可在一定程度上缓解农业环境污染,为改善农业环境,探寻农户实施亲环境行为的原因所在,将农户环境污染感知、环境关心和社会规范加入规范激活理论框架对其进行拓展,在此基础上,通过构建结构方程模型和层次回归模型,利用陕西、山西、甘肃、安徽和江苏5省的实地调查数据,对农户的亲环境行为进行分析。结果表明:农户的亲环境个人规范、环境污染感知和环境关心均可对其亲环境行为产生直接的正向影响,且个人规范对行为的影响程度最大;结果意识、责任归属、农户的环境污染感知和环境关心均可对其亲环境的个人规范产生直接的正向影响,且其影响程度从高到低依次为:结果意识、责任归属、环境污染感知和环境关心;农户的环境污染感知和环境关心可同时对其亲环境行为产生直接和间接影响作用,而结果意识和责任归属仅可对其亲环境行为产生间接影响作用;社会规范可正向调节个人规范对农户亲环境行为的影响。  相似文献   
996.
Russian Journal of Ecology - The present study was conducted to investigate the n-alkane composition of typical alpine meadows. Plant and soil samples were collected and analyzed to characterize...  相似文献   
997.
Wang  Jiaqing  Lu  Pei  Su  Wei  Xing  Yi  Li  Rui  Li  Yuran  Zhu  Tingyu  Yue  Huifang  Cui  Yongkang 《Environmental science and pollution research international》2019,26(20):20248-20263

Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts’ surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results.

  相似文献   
998.
Chen  Hui  Mao  Wei  Shen  Yiqiu  Feng  Weiwei  Mao  Guanghua  Zhao  Ting  Yang  Lanqin  Yang  Liuqing  Meng  Chunfeng  Li  Yong  Wu  Xiangyang 《Environmental science and pollution research international》2019,26(24):24609-24619

Phthalates (PAEs) in drinking water sources such as the Yangtze River in developing countries had aroused widespread concern. Here, the water, suspended particulate matter (SPM), and sediment samples were collected from 15 sites in wet and dry seasons in Zhenjiang, for the determination of six PAEs (DMP, DEP, DIBP, DBP, DEHP, and DOP) using the solid-phase extraction (SPE) or ultrasonic extraction coupled with gas chromatography-mass spectrometry (GC-MS). The total concentrations of six PAEs (Σ6PAEs) spanned a range of 2.65–39.31 μg L?1 in water, 1.97–34.10 μg g?1 in SPM, and 0.93–34.70 μg g?1 in sediment. The partition coefficients (Kd1) of PAEs in water and SPM phase ranged from 0.004 to 3.36 L g?1 in the wet season and from 0.12 to 2.84 L g?1 in the dry season. Kd2 of PAEs in water and sediment phase was 0.001–9.75 L g?1 in the wet season and 0.006–8.05 L g?1 in the dry season. The dominant PAEs were DIBP, DBP, and DEHP in water and SPM, DIBP, DEHP, and DOP in sediment. The concentration of DBP in water exceeded the China Surface Water Standard. The discharge of domestic sewage and industrial wastewater might be the main potential sources of PAEs. The risk quotient (RQ) method used for the risk assessment revealed that DBP (0.01 < RQ < 1) posed a medium risk, while DIBP and DEHP (RQ > 1) posed a high environmental risk in water, DIBP (RQ > 1) also showed a high risk in sediment.

  相似文献   
999.
Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
1000.
针对煤气脱硫废料(简称废料)的成分(硫、碳、萘及少量其他有机物),提出了一种处理废料的新工艺,先用乙酸乙酯提取废料中的萘和少量其他有机物,再用复合溶剂B加热溶解废料,热过滤得碳粉,最后将溶液冷却结晶分离出硫。实验结果表明:在乙酸乙酯与废料的质量比(R1)为3.75,提取温度为60℃,提取时间为4h的条件下,萘回收率为98%,纯度大于等于70%,在复合溶剂B与提取剩余物的质量比(R2)为2.69,过滤温度为100℃的条件下,硫回收率接近100%,纯度大于等于99%,碳回收率和纯度为100%。  相似文献   
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