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991.
加油站气液比检测方法及其影响 总被引:2,自引:0,他引:2
气液比(A/L)是加油站油气回收系统的一项重要控制指标,利用A/L测试仪、光离子化VOCs检测仪和油气排放因子测试装置,研究了不同A/L检测连接方式对A/L检测结果、检测人员暴露浓度、油气排放和油气回收效率等的影响。结果表明,不同连接方式和是否预先向检测油桶注油会导致A/L检测结果不一致,如果油桶与流量计不连接,A/L检测值将是实际A/L的1.04倍,当按照A/L=1.00~1.20调整加油枪A/L时,实际A/L将在0.96~1.15之间;按照国标GB20952-2007连接方式检测A/L可以减少检测过程中约80%的加油油气排放,夏季检测人员暴露油气浓度将由451×10-6(体积浓度)下降至91×10-6(体积浓度),油气排放因子将由1 056 mg/L下降至242 mg/L,更可减少因油罐吸入空气造成额外的汽油挥发排放,但不能减少倒油油气排放。 相似文献
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为准确分析区域资源环境承载力的整体状况及区域内部差异,推进经济社会发展与资源环境承载力相协调,以山东省为研究对象,构建包含人口、经济、资源与环境因素的区域资源环境承载力评价指标体系,以2014年山东省统计数据为基础,对全省和17个地级市资源环境承载力进行评估。结果表明:粗放型经济增长方式和资源环境本底脆弱导致山东省资源环境承载力不高,综合发展指数为0.33;17个地级市资源环境承载力序参量可分为4种类型,呈现出北部南部的空间分布特征,产生区域差异的原因主要有区位和自然条件因素、产业结构、技术水平、人才资源、经济发展水平等。 相似文献
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Chong Lin Wanhui Zhang Mengyang Yuan Chunhua Feng Yuan Ren Chaohai Wei 《Environmental science and pollution research international》2014,21(17):10329-10338
Coking wastewater treatment plant (CWWTP) represents a typical point source of polycyclic aromatic hydrocarbons (PAHs) to the water environment and threatens the safety of drinking water in downstream regions. To enhance the removal of residual PAHs from bio-treated coking wastewater, a pilot-scale O3/ultraviolet (UV) fluidized bed reactor (O3/UV FBR) was designed and different operating factors including UV irradiation intensity, pH, initial concentration, contact time, and hydraulic retention time (HRT) were investigated at an ozone level of 240 g h?1 and 25?±?3 °C. A health risk evaluation and cost analysis were also carried out under the continuous-flow mode. As far as we know, this is the first time an O3/UV FBR has been explored for PAHs treatment. The results indicated that between 41 and 75 % of 18 target PAHs were removed in O3/UV FBR due to synergistic effects of UV irradiation. Both increased reaction time and increased pH were beneficial for the removal of PAHs. The degradation of the target PAHs within 8 h can be well fitted by the pseudo-first-order kinetics (R 2?>?0.920). The reaction rate was also positively correlated with the initial concentrations of PAHs. The health risk assessment showed that the total amount of carcinogenic substance exposure to surface water was reduced by 0.432 g day?1. The economic analysis showed that the O3/UV FBR was able to remove 18 target PAHs at a cost of US$0.34 m?3. These results suggest that O3/UV FBR is efficient in removing residuals from CWWTP, thus reducing the accumulation of persistent pollutant released to surface water. 相似文献
994.
Hong Liu Hai Ren Qiang Liu XiangYing Wen Michael Maunder JiangYun Gao 《Conservation biology》2015,29(6):1537-1551
We assessed the current status of plant conservation translocation efforts in China, a topic poorly reported in recent scientific literature. We identified 222 conservation translocation cases involving 154 species, of these 87 were Chinese endemic species and 101 (78%) were listed as threatened on the Chinese Species Red List. We categorized the life form of each species and, when possible, determined for each case the translocation type, propagule source, propagule type, and survival and reproductive parameters. A surprisingly large proportion (26%) of the conservation translocations in China were conservation introductions, largely implemented in response to large‐scale habitat destruction caused by the Three‐Gorge Dam and another hydropower project. Documentation and management of the translocations varied greatly. Less than half the cases had plant survival records. Statistical analyses showed that survival percentages were significantly correlated with plant life form and the type of planting materials. Thirty percent of the cases had records on whether or not individuals flowered or fruited. Results of information theoretic model selection indicated that plant life form, translocation type, propagule type, propagule source, and time since planting significantly influenced the likelihood of flowering and fruiting on the project level. We suggest that the scientific‐based application of species conservation translocations should be promoted as part of a commitment to species recovery management. In addition, we recommend that the common practice of within and out of range introductions in nature reserves to be regulated more carefully due to its potential ecological risks. We recommend the establishment of a national office and database to coordinate conservation translocations in China. Our review effort is timely considering the need for a comprehensive national guideline for the newly announced nation‐wide conservation program on species with extremely small populations, which is expected to stimulate conservation translocations for many species in the near future. 相似文献
995.
Dai Shixiang Zhao Ling Teng Ying Wang Xiaomi Ren Wenjie 《Environmental science and pollution research international》2018,25(15):14656-14665
Environmental Science and Pollution Research - The fate and transport of polychlorinated biphenyls (PCBs), a class of persistent organic compounds, in soils was markedly affected by their... 相似文献
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Urban parks in India are often discussed as positive environmental projects, and their creation appears as unproblematic in public discourse. This paper presents the creation of a municipal park in a small city in Gujarat, India. Using insights from history and architecture, we stress the importance of reading parks as political and to some extent ideological projects in the larger context of city-making. The political ecology and history of the particular park studied here allow us to problematise the socio-ecological project of urban “beautification” via park creation. The municipal park, established in the centre of a small urban agglomeration after displacing a slum settlement from the site, is – as we argue – an integral part of a local geography of power. As such it expresses several registers of values upheld by local elites and brings into focus highly conflictive social relations. The case study contributes to further developing a situated urban political ecological approach that starts theorising cities from the South. It moreover offers a critical perspective on the understudied urban nature of small towns. 相似文献
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