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991.
阐述了武器装备环境分析时应考虑的运输环境危害因素,讨论了这些因素对武器装备的影响.认为增强武器装备本身的运输环境适应能力、通过科学的包装减缓环境影响、或两种方法同时使用,是提高武器装备运输环境适应性的有效途径. 相似文献
992.
Kai Qiao Zhijun Wu Xiangyu Pei Qianyun Liu Dongjie Shang Jing Zheng Zhuofei Du Wenfei Zhu Yusheng Wu Shengrong Lou Song Guo Chak K. Chan Ravi Kant Pathak Mattias Hallquist Min Hu 《环境科学学报(英文版)》2018,30(11):69-77
Particle density is an important physical property of atmospheric particles.The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles.In the present study,a centrifugal particle mass analyzer(CPMA) combined with a differential mobility analyzer(DMA) was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016.The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm~3,on average.The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm~3 for 50 to350 nm particles.Extra modes with peaks at 1.0,0.8,and 0.6 g/cm3 for 150,240,and 350 nm particles,which might be freshly emitted soot particles,were observed during intensive primary emissions episodes.The particle effective densities showed a diurnal variation pattern,with higher values during daytime.A case study showed that the effective density of Aitken mode particles during the new particle formation(NPF) event decreased considerably,indicating the significant contribution of organics to new particle growth. 相似文献
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Xianghui Cao Shouliang Huo Hanxiao Zhang Jiaqi Zheng Zhuoshi He Chunzi M Shuai Song 《环境科学学报(英文版)》2021,33(11):15-25
Emission intensity and climate change control the transport flux and fate of persistent organic pollutants (POPs) in multiple environmental compartments. This study applied a multimedia model (BETR model) to explore alternations in the spatio-temporal trends of concentrations and transport flux of benzopyrene (BaP), phenanthrene (Phe), perfluorooctane sulfonates (PFOS) and polychlorinated biphenyls (PCBs) in the Chaohu watershed, located in the lower reaches of the Yangtze River, China in response to changes in source emissions and climate. The potential historic and future risks of these pollutants also were assessed. The results suggest that current trends in concentrations and transport were similar to that of their emissions between 2005 and 2018. During the next 100 years, temporal trends and spatial patterns were not predicted to change significantly, which is consistent with climate change. Based on sensitivity and correlation analyses, climate change had significant effects on multi-media concentrations and transport fluxes of BaP, Phe, PFOS and PCBs, and rainfall intensity was the predominant controlling factor. Risk quotients (RQs) of BaP and Phe-in soil increased from 0.42 to 0.95 and 0.06 to 0.35, respectively, from 2005 to 2090, indicating potential risks. The RQs of the other examined contaminants exhibited little potential risk in soil, water, or sediment. Based on spatial patterns, it was inferred that the ecosystem around Lake Chaohu is the most at risk. The study provides insights needed for local pollution control of POPs in the Chaohu watershed. In addition, the developed approach can be applied to other watersheds world-wide. 相似文献
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基于2019年3月~2020年2月环境空气质量监测数据,分析了运城市PM2.5污染的时空分布特征,并利用HYSPLIT后向轨迹模型和聚类分析等方法探讨不同季节运城市PM2.5污染的输送路径和潜在源区.结果表明,运城市ρ(PM2.5)冬季最高(111.24μg·m-3),夏季最低(30.02μg·m-3),PM2.5/PM10秋冬季均大于0.6,表明运城市秋冬两季颗粒物污染以细颗粒物为主;空间上ρ(PM2.5)年均值呈现北部和中部高、东部和西部低的分布特征,高值区PM2.5与SO2、 NO2和CO呈显著强相关,表明本地排放对高值区ρ(PM2.5)影响较大,春季和冬季最高值分别位于河津市(58.50μg·m-3)和稷山县(142.33μg·m-3),夏季最高值位于南部的平陆县(36.92... 相似文献
998.
Graeme Sherriff 《Local Environment》2015,20(12):1507-1530
In December 2008, the Greater Manchester electorate voted to reject a £3 billion package of transport measures that would have included investment in the conurbation's bus, tram and rail networks and walking and cycling infrastructure, together with, and partially funded by, the introduction of a congestion charge. The proposals followed a successful bid to the UK Government Transport Innovation Fund (TIF). High levels of car use present challenges to cities, and the TIF bid can be seen as an attempt to address these by promoting and facilitating a modal shift. The paper reflects on the debates surrounding the proposals, which led to a referendum. In particular, it explores the challenges of communicating complex, controversial plans in a fragmented and contested political arena. 相似文献
999.
An intelligent disaster decision support system for increasing the sustainability of transport networks 下载免费PDF全文
The increase in extreme weather events arising from climate change is posing serious threats to the sustainability of transport systems, creating the need for improved tools for decision support for more effectively managing natural disasters. There are numerous transport‐related decisions that are required during the response, recovery and preparedness stages of the disaster management cycle. This paper describes the development and application of the Intelligent Disaster Decision Support System (IDDSS), which provides a platform for integrating a vast range of road network, traffic, geographic, economic and meteorological data, as well as dynamic disaster and transport models. Initial applications to the response and planning for floods and fires are presented to illustrate some of its capabilities. The IDDSS can be used to improve disaster management, which in turn will increase the sustainability of transport networks. 相似文献
1000.
E.S. Brooks S.M. Saia J. Boll L. Wetzel Z.M. Easton T.S. Steenhuis 《Journal of the American Water Resources Association》2015,51(2):343-358
There is an increasing need for improved process‐based planning tools to assist watershed managers in the selection and placement of effective best management practices (BMPs). In this article, we present an approach, based on the Water Erosion Prediction Project model and a pesticide transport model, to identify dominant hydrologic flow paths and critical source areas for a variety of pollutant types. We use this approach to compare the relative impacts of BMPs on hydrology, erosion, sediment, and pollutant delivery within different landscapes. Specifically, we focus on using this approach to understand what factors promoted and/or hindered BMP effectiveness at three Conservation Effects Assessment Project watersheds: Paradise Creek Watershed in Idaho, Walnut Creek Watershed in Iowa, and Goodwater Creek Experimental Watershed in Missouri. These watersheds were first broken down into unique land types based on soil and topographic characteristics. We used the model to assess BMP effectiveness in each of these land types. This simple process‐based modeling approach provided valuable insights that are not generally available to planners when selecting and locating BMPs and helped explain fundamental reasons why long‐term improvement in water quality of these three watersheds has yet to be completely realized. 相似文献