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421.
Jingyan Li Tingting Xu Xiaohui Lu Hong Chen Sergey A. Nizkorodov Jianmin Chen Xin Yang Zhaoyu Mo Zhiming Chen Huilin Liu Jingying Mao Guiyun Liang 《环境科学学报(英文版)》2017,29(3):184-195
Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO_2, coarse mode, and accumulation mode(100–500 nm) particles. Through single particle mass spectrometry analysis, five different types of particles(fireworks-metal, ash, dust, organic carbon-sulfate(OC-sulfate), biomass burning) with different size distributions were identified as primary emissions from firework displays. The fireworks-related particles accounted for more than70% of the total analyzed particles during severe firework detonations. The formation of secondary particulate sulfate and nitrate during firework events was investigated on single particle level. An increase of sulfite peak(80SO_3~-) followed by an increase of sulfate peaks(97HSO_4~-+ 96SO_4~-) in the mass spectra during firework displays indicated the aqueous uptake and oxidation of SO_2 on particles. High concentration of gaseous SO_2, high relative humidity and high particle loading likely promoted SO_2 oxidation. Secondary nitrate formed through gas-phase oxidation of NO_2 to nitric acid, followed by the condensation into particles as ammonium nitrate. This study shows that under worm, humid conditions, both primary and secondary aerosols contribute to the particulate air pollution during firework displays. 相似文献
422.
Yiding M Zongshuang Wang Yufei Tan Shu Xu Shaofei Kong Gang Wu Xuefang Wu Hong Li 《环境科学学报(英文版)》2017,29(5):339-353
To compare the inorganic chemical compositions of TSP(total suspended paniculate),PM_(10)(particulate matter with an aerodynamic diameter less than 10 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter less than 2.5 μm) in southern and northern cities in China,atmospheric particles were synchronously collected in Dalian(the northern city)and Xiamen(the southern city) in spring and autumn of 2004.The mass concentrations,twenty-three elements and nine soluble ions were assessed.The results show that in Dalian,the mass concentrations of Mg,Al,Ca,Mn and Fe in spring were 4.0-10.1,2.6-8.0,4.1-12,1.2-3.6 and 2.9-7.9 times higher,respectively,than those in Xiamen.The dust storm influence is more obvious in Dalian in spring.However,in Xiamen,heavy metals accounted for 13.9%-17.9%of TSP,while heavy metals contributed to 5.5%-9.3%of TSP in Dalian.These concentrations suggest that heavy metal pollution in Xiamen was more serious.In addition,the concentrations of Na~+,Cl~-,Ca~(2+) and Mg~(2+) were higher in Dalian due to the influence of marine aerosol,construction activities and soil dust.The NO~(3-)/SO_4~(2-) ratios in Dalian(0.25-0.49) were lower than those in Xiamen(0.51-0.62),indicating that the contributions of vehicle emission to particles in Xiamen were higher.Coefficient of divergence values was higher than 0.40,implying that the inorganic chemical composition profiles for the particles of Dalian and Xiamen were quite different from each other. 相似文献
423.
竹产业既是传统行业又是新兴产业,在国家提倡的节能减排和环境保护过程中扮演重要角色.通过分析竹产业的现状,十分有必要给竹产业企业建立MFCA账户.同时,通过对浙江S拉丝企业的MFCA分析,建议S竹拉丝企业在能量损耗和机械折旧率控制上减少不必要的消耗,如精准控制无聊投放的时间节点,并且减少系统资源成本,积极与当地政府沟通,达成在政策层面有效支持节能减排和环境保护的推广,如与环境紧密关联的负产品处置补贴等. 相似文献
424.
Jia He Cun-Kuan Bao Ting-Fei Shu Xiao-Xue Yun Dahe Jiang Lex BrwonAuthor vitae 《Environmental Impact Assessment Review》2011,31(6):549-560
Sustainable development or sustainability has been highlighted as an essential principle in urban master planning, with increasing recognition that uncontrollable urbanization may well give rise to various issues such as overexploitation of natural resources, ecosystem destruction, environmental pollution and large-scale climate change. Thus, it is deemed necessary to modify the existing urban and regional administrative system so as to cope with the challenges urban planning is being confronted with and realize the purpose of urban sustainability. This paper contributed to proposing a mechanism which helps to make urban planning with full consideration of issues with respect to sustainable development. We suggested that the integration of urban planning, SEA and ecological planning be a multi-win strategy to offset deficiency of each mentioned political tool being individually applied. We also proposed a framework where SEA and ecological planning are fully incorporated into urban planning, which forms a two-way constraint mechanism to ascertain environmental quality of urban planning, although in practice, planning and SEA processes may conditionally be unified. Moreover, as shown in the case study, the integration of the three political tools may be constrained due to slow changes in the contextual factors, in particular the political and cultural dimensions. Currently within the context of China, there may be three major elements which facilitate integration of the three political tools, which are (1) regulatory requirement of PEIA on urban planning, (2) the promotion or strong administrative support from government on eco-district building, and (3) the willingness of urban planners to collaborate with SEA experts or ecologists. 相似文献
425.
Xue Song Wang Guang Chao Zhu Shu Jun Wang Wen Ya Wan Ye Bin Tan 《Environmental monitoring and assessment》2011,177(1-4):263-272
The concentrations and chemical partitioning of heavy metals (Co, Cr, Ni, Zn, Cu, and Pb) in the marine near-shore sediment cores were investigated. Typically, the mean concentrations from Core B sediment samples were 98.6, 21.1, 47.0, 46.4, 107.6, and 31.9 mg kg???1 for Cr, Co, Ni, Cu, Zn, and Pb, respectively. The heavy metal concentrations were normalized to commonly used reference elements Al, Li, Sc, and total organic carbon. Based on Pearson coefficients, Li was found to be a good normalizer for Co (r?= 0.974), Cr (r?= 0.967), Ni (r?= 0.898), and Zn (r?= 0.929) in 80 sediment samples from three sampling sites. However, the correlation coefficients between Li and Cu, and Li and Pb were relatively low. Multivariate statistic approaches (Principal Component Analysis and Cluster Analysis) were adopted for data treatment, allowing the identification of two main factors controlling the heavy metal variability in the sediments. Heavy metals in the enrichment sections were evaluated by a sequential extraction method for possible chemical forms in sediments. The results showed that the residual, Fe/Mn oxides and Organic/sulfide fractions were dominant geochemical phases in the enriched sections, indicating low bioavailability of heavy metals in sediments. 相似文献
426.
427.
428.
GIS技术在土地资源估价中的应用分析 总被引:1,自引:0,他引:1
本文主要分析了GIS技术的功能、概念、发展及基于该技术的土地估价信息系统的组成、功能和优越性。为土地估价提供了强有力的技术支持和科学依据 相似文献
429.
在沙尘暴应急监测方法研究中,通过对总悬浮颗粒物采样仪器及各种采样参数的研究确定和降尘采样器的研制,制定出沙尘暴应急监测方法。 相似文献
430.