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21.
<正>1.Editor's note On 30 November 2016,the Brookings-Tsinghua Center for Public Policy(BTC),Caixin Video,and Columbia Global Centers(Beijing)jointly hosted a Seminar on the Future of Global Governance and Climate Change Action in a Changing Political Landscape.Leading experts on China's environmental policy and climate  相似文献   
22.
Sun J  Hu J  Peng H  Shi J  Dong Z 《Chemosphere》2012,87(1):37-42
Increasing antibacterial resistance and pathogenicity in the environment is of growing concern due to its potential human risk. In the present study, 236 Escherichia coli isolates were collected from Wenyu River in China on drugless (48 isolates) and quinolone-containing plates (189 isolates). Their minimum inhibitory concentrations (MICs) were determined ranging from 0.125 μg mL−1 to 128 μg mL−1. Mutation points related to fluoroquinolone resistance were observed at S83 to L and D87 to N or Y in the GyrA subunit and S80 to R or I and E84 to G in the ParC subunit. Generally, MICs of LEV and GAT are dependent on the patterns of these mutation points. The profile with three mutation points was related to LEV-resistant E. coli isolates, and the (S83L, D87N + S80I) mutation profile was most prevalent (65.7%) in LEV-resistant isolates, while a large proportion of isolates, even those with three mutation points, were susceptive to GAT. The incidence of virulence factors in LEV-resistant isolates (44.7%, 59/132) was much higher than in nonresistant isolates (23.1%, 24/104) (χ2 = 11.925, 1° of freedom, p < 0.001) indicating that fluoroquinolone-resistant E. coli would pose a potential risk. A similar distribution was also found in isolates resistant to GAT (χ2 = 7.843, 1° of freedom, = 0.0079).  相似文献   
23.
随着电子信息产业的高速发展和人民生活水平的不断提高,电子废弃物的数量也不断增长,成为21世纪增长最快的固体废弃物。从我国电子废弃物的回收利用现状入手进行分析,提出建设一套专业回收利用体系,形成以城市社区回收点为基础,中转交投中心为纽带,资源循环利用为目的,点面结合、三位一体的电子废弃物回收利用体系,逐步提高回收、集散、循环利用能力,促进行业健康、有序发展。  相似文献   
24.
Anthropogenic biomass burning in insular Southeast Asia facilitates conversion and degradation of ecosystems and emits high amounts of carbon into the atmosphere. We analyzed the influence of peat soil and land cover distribution on the occurrence and characteristics of vegetation fires. Two years of satellite-based active fire detections over Peninsular Malaysia, Sumatra, Borneo and Java were examined together with land cover and peatland maps. Our results showed that fire occurrence nearly tripled (23,000 → 68,000) from a wet La Niña year (2008) to a drier El Niño year (2009). In both years, fires were concentrated in peatlands (in 2009 41% of fires vs. 10% of land area), and the majority of large-scale burning took place in peatlands. Variation in peatland land cover within the study area was noticed to create remarkable different fire regimes. Biomass burning in the intensely managed Sumatran peatlands was characterized by large-scale land clearance fires that took place annually to varying extent. The largely unmanaged degraded peatland ecosystems of Borneo, on the other hand, experienced very little fire activity in a wet year but were ravaged by large-scale wildfires when El Niño conditions arose. We conclude that fire regime characteristics in insular Southeast Asia are strongly connected to occurrence of peat soil and land management status. This leads to high variation of fire activity within this region both annually (depending on weather patters) and over longer time range (depending on land cover/management issues) and greatly complicates estimation of the effects of fires.  相似文献   
25.
1972年联合国在瑞典的斯德哥尔摩召开了有113个国家参加的联合国人类环境会议。会议讨论了保护全球环境的行动计划,通过了《人类环境宣言》。会议建议联合国大会将这次会议开幕的6月5日定为“世界环境保护日”。同年10月联合国大会第27届会议接受并通过了这一建议。每年的6月5日,世界各国都开展群众性的环境保护宣传纪念活动,以唤起全世界人民都来注意保护人类赖以生存的环境,自觉采取行动参与环境保护的共同努力,同时要求各国政府和联合国系统为推进环境保护进程做出贡献。  相似文献   
26.
鲁实  郭冰  晓萍 《防灾博览》2007,(5):40-43
2007年是历史上的灾难年。由于受全球气候变暖影响,我国多个省市发生了各种自然灾害,如干旱、洪水、泥石流、滑坡、飓风等,尤其是洪涝灾害,经济损失惨重。另有朝鲜、缅甸以及南亚的印度、孟加拉国、尼泊尔也成了一片泽国;就连美国也未幸免于洪灾。现简述如下。  相似文献   
27.
Environmental Science and Pollution Research - The aim of this work was to explore the potential application of biochar from distillers’ grains anaerobic digestion residue pyrolyzed at...  相似文献   
28.
Based on hourly measurements of NOx NO2 and O3 and meteorological data, an ordinary least squares (OLS) model and a first-order autocorrelation (AR) model were developed to analyse the regression and prediction of NOx and NO2 concentrations in London. Primary emissions and wind speed are the most important factors influencing NOx concentrations; in addition to these two, reaction of NO with O3 is also a major factor influencing NO2 concentrations. The AR model resulted in high correlation coefficients (R > 0.95) for the NOx and NO2 regression based on a whole year's data, and is capable of predicting NO2 (R = 0.83) and NOx (R = 0.65) concentrations when the explanatory variables were available. The analysis of the structure of regression models by Principal Component Analysis (PCA) indicates that the regression models are stable. The results of the OLS model indicate that there was an exceptional NO2 source, other than primary emission and reaction of NO with O3, in the air pollution episode in London in December 1991.  相似文献   
29.
根据蜂窝断面内循环三相生物流化床内混合液的连续性方程、动量方程和能量方程,利用Fluent软件对反应器内的流动状况进行了数值模拟.采用Fluent的前处理软件Gambit完成流化床的三维模型,利用Fluent主程序解析计算,并利用后处理软件实现计算结果的显示.模拟计算结果获得了反应器内静压力、静压差的变化规律,得到了液体循环速度、气含率沿纵向及横断面的分布.  相似文献   
30.
Status of trace elements in paddy soil and sediment in Taihu Lake region   总被引:14,自引:0,他引:14  
Wang XC  Yan WD  An Z  Lu Q  Shi WM  Cao ZH  Wong MH 《Chemosphere》2003,50(6):707-710
Thirteen paddy soil profiles and river sediments which are sources of irrigation water were collected around the Taihu Lake, and the trace elements were estimated. The content of La and Ce in paddy soil and sediment were 39.3 and 68.6 mg/kg soil and 36.9 and 65.1 mg/kg soil, being within the range of background values. The values for Pb, Cu, Ni, Cr, Co, Mn, Zn, Se in paddy soil were 23.3, 27.8, 25.5, 63.5, 10.2, 386, 68.7 and 0.25 mg/kg soil respectively, all below the national permission level. There was a decline of Zn in paddy soil. Some of the river sediments were seriously polluted. The river in Yangjin site was most contaminated with 5.47 g Cu/kg and 7.4 g Zn/kg. The high concentration of Pb and Ni also was observed in this sediment. River in Weitang, Huashi, Xinzhuang and Meiyan were contaminated with Pb, Cu and Ni to some extent. Zn, Cu and Pb were the main pollutants in present experiment sites. The fast development of village/township industries have caused severe environmental pollution in the Taihu Lake region, especially irrigation river sediments. Se content in plant and seed was 0.04 and 0.03 mg/kg respectively, showed Se-deficiency in paddy soil in the Taihu Lake region.  相似文献   
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