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251.
This article examines local recovery plans that were created in response to the Wenchuan earthquake and then suggests ways that planners can better apply the concept of sustainability to the recovery process. We utilize a plan evaluation protocol to analyze 16 recovery plans in counties and towns that were severely affected by the earthquake. We also conducted semi-structured interviews with public officials and planners, with the qualitative data gleaned from these interviews being used to supplement the plan quality assessment. The results reveal that local recovery plans do not appear to have incorporated sufficiently the concepts of sustainability. We conclude the paper with the following recommendations: emphasizing sustainability as a policy priority during vision and goal development; developing solid databases and planning techniques; designing a diversified set of regulatory- and incentive-based policy tools suitable for local governments; enhancing social and institutional learning; and further integrating multi-level and interagency governmental units.  相似文献   
252.
A biofilm membrane bioreactor (BF-MBR) and a conventional membrane bioreactor (MBR) were parallelly operated for treating digested piggery wastewater. The removal performance of COD, TN, NH4 +-N, TP as well as antibiotics were simultaneously studied when the hydraulic retention time (HRT) was gradually shortened from 9 d to 1 d and when the ratio of influent COD to TN was changed. The results showed that the effluent quality in both reactors was poor and unstable at an influent COD/TN ratio of 1.0±0.2. The effluent quality was significantly improved as the influent COD/TN ratio was increased to 2.3±0.5. The averaged removal rates of COD, NH4 +-N, TN and TP were 92.1%, 97.1%, 35.6% and 54.2%, respectively, in the BF-MBR, significantly higher than the corresponding values of 91.7%, 90.9%, 17.4% and 31.9% in the MBR. Analysis of 11 typical veterinary antibiotics (from the tetracycline, sulfonamide, quinolone, and macrolide families) revealed that the BF-MBR removed more antibiotics than the MBR. Although the antibiotics removal decreased with a shortened HRT, high antibiotics removals of 86.8%, 80.2% and 45.3% were observed in the BF-MBR at HRTof 5–4 d, 3–2 d and 1 d, respectively, while the corresponding values were only 83.8%, 57.0% and 25.5% in the MBR. Moreover, the BF-MBR showed a 15% higher retention rate of antibiotics and consumed 40% less alkalinity than the MBR. Results above suggest that the BF-MBR was more suitable for digested piggery wastewater treatment.
  相似文献   
253.
Airborne carbonyls were characterized from emitted indoor coal combustion. Samples were collected in Xuanwei (Yunnan Province), a region in China with a high rate of lung cancer. Eleven of 19 types of samples (58%) demonstrated formaldehyde concentrations higher than the World Health Organization exposure limit (a 30-min average of 100 μg m?3). Different positive significant correlations between glyoxal/methylglyoxal and formaldehyde/acetaldehyde concentrations were observed, suggesting possible different characteristics in emissions between two pairs of carbonyl compounds. A sample in the highest inhalation risk shows 29.2 times higher risk than the lowest sample, suggesting different coal sampling locations could contribute to the variation of inhalation risk. Inhabitants in Xuanwei also tend to spend more time cooking and more days per year indoors than the national average. The calculated cancer risk ranged from 2.2–63 × 10?5, which shows 13 types of samples at high-risk level. Cumulative effect in combination with different carbonyls could have contributed to the additive actual inhalation cancer risk. There is a need to explicitly address the health effects of environmentally relevant doses, considering life-long exposure in indoor dwellings.  相似文献   
254.
Environmental Science and Pollution Research - The bamboo flowering leads to the habitat fragmentation and food quality decline of a giant panda. Few empirical research has been conducted about the...  相似文献   
255.
Environmental Science and Pollution Research - Microcystis aeruginosa (M. aeruginosa) is one of the most common genera of cyanobacteria in algal blooms. In the present work, the impact of the...  相似文献   
256.
The contamination characteristics of arsenic and other trace elements in groundwater and the potential risks of arsenic from the groundwater were investigated. Elevated contamination of arsenic, barium and manganese was observed in tube-well water of two villages (Chuyen Ngoai and Chau Giang) in Ha Nam province in the Northern Vietnam. Concentrations of As in the groundwater ranged from 12.8 to 884 µg/L with mean values in Chuyen Ngoai and Chau Giang were 614.7 and 160.1 µg/L, respectively. About 83 % of these samples contained As concentrations exceeding WHO drinking water guideline of 10 μg/L. The mean values of Mn and Ba in groundwater from Chuyen Ngoai and Chau Giang were 300 and 657 μg/L and 650 and 468 μg/L, respectively. The mean value of Ba concentration in groundwater in both Chuyen Ngoai and Chau Giang was about 22 % of the samples exceeded the WHO guideline (700 µg/L). Arsenic concentrations in human urine of residents from Chuyen Ngoai and Chau Giang were the range from 8.6 to 458 µg/L. The mean values of Mn and Ba in human urine of local people from Chuyen Ngoai were 46.9 and 62.8 μg/L, respectively, while those in people from Chau Giang were 25.9 and 45.9 μg/L, respectively. The average daily dose from ingesting arsenic for consuming both untreated and treated groundwater is from 0.02 to 11.5 and 0.003 to 1.6 μg/kg day, respectively. Approximately, 57 % of the families using treated groundwater and 64 % of the families using untreated groundwater could be affected by elevated arsenic exposure.  相似文献   
257.
Western China has lagged a lot in terms of industrial structure and economic development,compared with the national average.And China announced its target of CO_2 emission reduction,i.e.by 2020,CO_2 emission per GDP will drop by40-45%compared with 2005.The target will be incorporated into China's long-term industrial planning.Against this background,this paper will make a comprehensive examination of the industrial development of Western China,aiming to discover a green and compatible way.First,we analyze the spatiotemporal evolution of regional industrial structure for the period 2000-2010.Second,we try to discover the industrial structure optimization path for Western China by employing the Vector Auto Regression model.Lastly,we try to provide some advice and suggestions for further industrial development in Western China.Our examination shows that further industrial development in Western China should pay full attention to resource conservation and recycling,and develop on a green and compatible path.  相似文献   
258.
能源消费总量控制是保障能源安全,积极应对气候变暖的重要手段;省域内能源消费量的合理分配,是落实国家能源消费总量控制的有效措施。提出能源消费总量分配应以公平为主、考虑区域发展权益的同时兼顾效率的原则,秉承“定基数,分增量”的思想,构建了基于信息熵的多因子混合加权分配模型,对目标年能源消费增量进行分配;选择了10个指标从经济水平、能耗水平、发展现状、产业结构及城市发展定位5个方面描述各地区的节能潜力及控制能耗量的责任,拟对能源消费总量在省内各市区的分配进行探索性研究。并以安徽省为例,对安徽省2015年能源消费总量分配到各市区进行了实证分析。结果显示,2015年安徽省17个市区能耗分配量增长率范围为1193%~5045%,能耗增幅的分配结果整体上受各市区人均GDP和人均能源消费量水平所支配,受单位工业增加值能耗和城市化率所调控  相似文献   
259.
易然  徐静  宋玉栋  周岳溪  张胜  王红 《化工环保》2013,33(4):289-293
采用氨基膦酸螯合树脂C-900去除丙烯酸丁酯废水中的二价阳离子,考察了吸附温度和废水流量对树脂动态吸附性能的影响,并用Thomas模型进行动态吸附数据的拟合分析。实验结果表明,在吸附温度为35℃、废水流量为15SV的条件下,处理后出水中3种二价阳离子总质量浓度为1.0mg/L时的穿透体积为240BV,达到穿透体积时树脂对Ca2+,Mg2+,Cu2+的去除率分别为100%,99.2%,99.8%。  相似文献   
260.
The life cycle assessment of an e-waste treatment enterprise in China   总被引:1,自引:0,他引:1  
Electrical and electronic waste (e-waste) has become one of the fastest growing waste streams in the world, and many countries have established e-waste treatment enterprises to solve their e-waste problems. In this study, a life cycle assessment (LCA) was undertaken to quantitatively investigate the environmental impacts of an e-waste treatment enterprise in China. The LCA is constructed by SimaPro software version 7.2 and expressed with the Eco-indicator 99 life cycle impact assessment method. For a sensitivity analysis of the overall LCA results, the so-called CML method is used in order to estimate the influence of the choice of the assessment method on the result. According to the survey data, discarded TV sets accounted for the highest proportion of e-waste treated in the enterprise in 2010. The e-waste treatment had little environmental impact, and at the same time large environmental benefits can be achieved mainly due to the recycled resources and reuse of some components. Based on the research results, it can be seen that recycled metal, especially copper, would be of more importance for environmental benefits. Relevant results and data from this study could provide decision support to enterprise managers and government sectors.  相似文献   
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