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911.
912.
城市绿色发展竞争力评价研究 总被引:3,自引:0,他引:3
提出城市绿色发展竞争力概念,探讨环境质量与经济社会发展水平之间的关系,从城市空气环境质量、地表水环境质量、声环境质量、集中式饮用水源地水质和生态环境质量等"硬环境"着手,结合衡量城市经济发展程度的工业GDP指标,构建评价指标体系,用单位工业GDP的环境代价来表征城市绿色发展竞争力水平,并以安徽省省辖市为例进行了实例研究。 相似文献
913.
Yuanyuan Li Tian Lin Yanwen Qin Lei Zhang Zhigang Guo 《Environmental monitoring and assessment》2013,185(11):8861-8871
The Xiangjiang River (XR), the second largest tributary of the Yangtze River, is mainly located in Hunan province in south-central China. Nineteen surface sediment samples (the top 3-cm layer) collected from XR were analyzed to determine the concentrations, distribution, sources, and ecological risk of organochlorine pesticides (OCPs). The concentrations of OCPs were 3.0–29.8 ng/g (dry weight) with a mean of 12.6?±?7.7 ng/g. The widely detected compounds included HCHs, DDTs, HCB, and dieldrin. Overall, the dominant OCPs in the sediments were mainly composed of residual and degradation products, e.g., β-HCH with a mean of 42.2 % in HCHs and p,p′-DDE with a mean of 43.5 % in DDTs, implying that OCPs in the sediments had suffered from long-term aging without fresh inputs in XR. However, there was a high proportion of p,p′-DDT to DDTs in three sites, suggesting that there was use of technical DDT from their surrounding areas at present. The ratios of α-HCH/γ-HCH and p,p′-DDD?+?p,p′-DDE/DDTs increase from the upper reaches to the lower reaches of XR, suggesting sediments enriched with α-HCH and metabolites DDD and DDE during sediment transport process and could be attributed to the transformation of γ-HCH to α-HCH and DDT to DDE or DDD. The assessment of the ecological risk indicates that the OCPs in the sediments of XR have a moderate adverse biological effect on organisms. 相似文献
914.
北京市大气PM10源解析研究 总被引:10,自引:5,他引:10
于2004年在北京市定陵、车公庄、古城、亦庄、房山和奥体中心6个采样点采集大气PM10环境样品,针对北京市颗粒物主要排放源采集土壤尘、建筑水泥尘、燃煤等污染源PM10样品,分别对其中的无机元素、离子、有机碳(OC)和元素碳(EC)进行测定。采用代表北京市颗粒物主要排放源PM10组分特征的成分谱,利用CMB受体模型对PM10来源进行解析。结果表明,PM10的最大来源为土壤尘,其它贡献源类依次为燃煤排放、机动车/燃油排放、二次粒子(SO42-、NO3-和NH4 )、建筑水泥尘。污染源贡献具有明显的季节变化,并存在一定的地域变化。 相似文献
915.
合流制排水系统雨天溢流污染CMB法源解析 总被引:3,自引:1,他引:3
对上海市某合流制排水系统服务范围内的地表径流、旱流污水和管道沉积物的污染物特性进行检测分析,通过对比不同污染源的污染特征,确定Zn、NH+4-N、P的含量分别在地表径流、旱流污水和管道沉积物中具有特异性且相对稳定,提出以Zn/P、NH+4-N/Zn、P/K这3个无量纲比值作为上述3个排放源各自的特征参数,据此探讨了CMB法在合流制雨天溢流污染源解析中的应用,结果表明,地表径流、旱流污水和管道沉积物对溢流污染的平均贡献率分别为42.8%、12.2%、23.8%,解析结果可基本反映CSO污染的构成情况.研究方法与结果为合流制系统雨天溢流污染源解析提供了参考. 相似文献
916.
对 CFRP 箍筋和纵筋增强钢纤维混凝土梁的受剪承载力进行研究,通过 6 根梁的加载试验研究了剪跨比、配箍率和箍筋种类对受剪承载力的影响。考虑 CFRP 纵筋与混凝土的粘结性能,建立了 CFRP 筋增强钢纤维梁受剪承载力计算方法。结果表明:①CFRP 筋增强钢纤维混凝土梁受剪承载力高,破坏前斜裂缝宽度大,破坏有明显预兆;②钢纤维可有效减小斜截面开裂后前期的 CFRP 箍筋应力,有利于箍筋强度发挥,CFRP 箍筋的极限应变可取为 0.004;③CFRP 纵筋发挥强度高,需注意锚固长度和设计使用应力,防止滑移拔出和销栓破断;④给出的受剪承载力计算方法具有较高的计算精度高。 相似文献
917.
Xinhai Li Huidong Tian Yuan Wang Renqiang Li Zengming Song Fengchun Zhang Ming Xu Dianmo Li 《Regional Environmental Change》2013,13(4):843-852
We assessed the vulnerability of 208 endemic or endangered species in China to the effects of climate change, as a part of the project “Research on China’s National Biodiversity and Climate Change Strategy and Action Plans”. Based on the China Species Information System, we selected comprehensive species as analysis targets, covering taxa including mammals, birds, reptiles, amphibians and plants. We applied nine species distribution models in BIOMOD (a package of R software) to estimate the current (1991–2010) ranges and predicted future (2081–2100) ranges of these species, using six climate variables based on Regional Climate Model version 3 (RegCM3) and A1B emission scenario. The model results showed that different taxa might show diverse potential range shifts over time. The range sizes of half of the species (104 species) would decrease, and those of another half would increase. We predicted that the future remaining ranges (intersection of current and future ranges/current ranges) of 135 species would be less than 50 % of their current range sizes. Species that are both endemic and critically endangered would lose more of their range than others. In summary, the most vulnerable species are currently found on the Qinghai-Tibetan Plateau, in the Hengduan Mountain Range, and southern China. Future action plans dealing with climate change in China should be prepared with consideration for vulnerable species and their habitats. 相似文献
918.
本文介绍了主流的运维管理ITIL框架体系,通过对吉林省环保专网的梳理和优化流程,以信息化手段提升环境管理水平,实现以环保业务为中心,提高行政服务效率,同时降低运维风险。 相似文献
919.
Cao Xinqiang Gu Yan Fang Yanfen Johnson David Chen Chuncheng Chen Junsong Tian Hailin Huang Yingping 《Environmental Chemistry Letters》2022,20(3):1595-1601
Environmental Chemistry Letters - There is a lack of efficient methods for removing microcystins produced by cyanobacterial blooms. Here, microsphere-like bismuth vanadate (BiVO4-60) mesocrystals... 相似文献
920.
Zhang Tian Jiang Bo Xing Yi Ya Haobo Lv Mingjie Wang Xin 《Environmental science and pollution research international》2022,29(12):16830-16859
Environmental Science and Pollution Research - Microplastics, as emerging pollutants, have received great attention in the past few decades due to its adverse effects on the environment.... 相似文献