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301.
近年来,随着我国机动车保有量的持续增长,机动车排放已成为我国重要的大气污染物来源之一.现有的机动车排放研究多关注城市内的机动车大气污染物排放,针对城市间的大气污染物排放研究较少.我国城市间交通道路主要包括国道和省道,截止至2015年我国国道里程18.53万km、省道里程32.97万km,约占全国等级公路总里程的13%,因此开展我国国道和省道机动车大气污染物排放研究十分重要.本研究基于全国国道和省道交通监测站的年均监测数据,采用环境保护部发布的《道路机动车大气污染物排放清单编制技术指南(试行)》中的指导方法,计算了2015年我国国道和省道机动车的大气污染物排放清单,分析了污染物排放的时空分布特征.结果表明,我国国道和省道公路机动车排放的一氧化碳(CO)、氮氧化物(NO_x)、颗粒物(PM)和碳氢化合物(HC)排放量分别占全国机动车污染物总排放量的4.5%、27.9%、14.4%和7.7%;不同车型对国道和省道机动车大气污染物排放的分担率不同,其中大货车是NO_x、PM_(10)、PM_(2.5)的主要来源,摩托车是CO和HC的主要来源;不同道路类型中各车型的大气污染物排放分担率也不同,如高速路上大货车是NO_x、PM_(10)和PM_(2.5)的主要来源,普通道路上大客车和大货车是NO_x、PM_(10)和PM_(2.5)的主要来源. 相似文献
302.
Zhike Li Jie Chi Zhenyu Wu Yiyan Zhang Yiran Liu Lanlan Huang Yiren Lu Minhaz Uddin Wei Zhang Xuejun Wang Yan Lin Yindong Tong 《Frontiers of Environmental Science & Engineering》2022,16(3):37
303.
304.
系统梳理了污染源监督性监测数据元的研究现状,提出了污染源监督性监测数据元的构建过程和体系指标,为制定污染源监督性监测数据元技术标准提供技术支持。通过污染源监督性监测数据元的构建,建立监测数据共享和应用的长效机制,实现污染源监督性监测信息的规范管理、交换与共享,为各级环保部门加强对污染源的监管和政府决策提供强有力的技术支持。 相似文献
305.
海河下游水体中DO与NH_3-N、COD_(Mn)相关关系探讨 总被引:2,自引:0,他引:2
本文应用近年来海河下游监测数据对DO与NH3N和CODMn进行一元线性回归,得到两回归方程:NH3N=-128DO+1054;CODMn=-113DO+1692。并经相关系数和回归系数显著性检验,表明在999%的置信水平下DO与NH3N和CODMn线性相关均极其显著 相似文献
306.
结合环境监测实验实质量控制数据处理的实际要求,用计算机高级语言,设计开发成功了《精密度-偏性分析质控试验数据处理系统》,该系统具有数据输入,查询,修改,统计分析和打印报告等功能,在实际应用中,取得良好效果。 相似文献
307.
在机制上将一个地市(淮南市)的地震预报与防震决策融为一个动态整体,从而建立起一个实用性强的防震减灾决策系统,使城市各种防震对策的生成有了更科学的基础。成为市政府在防震减灾决策中不可缺少的工具。 相似文献
308.
Megan Rothenberger Andrea Armstrong Trent Gaugler Sarah Massaro William Pfadenhauer Juliana Ventresca 《Conservation biology》2020,34(6):1560-1570
We devised a practical method for integrating information on 2 marine invasive species using 3 different approaches: standardized ecological monitoring, online-reporting databases, and surveys of anglers and crabbers. Focusing on 2 recently introduced species with different characteristics, the Asian shore crab (Hemigrapsus sanguineus) and Chinese mitten crab (Eriocheir sinensis), in the Hudson-Raritan watershed of New York and New Jersey, we used sensitivity analyses to explore the relative contribution of each information source to knowledge of species abundance and distribution. All 3 information sources contributed something unique to understanding abundance and distribution of the introduced crabs. Online and survey data on Asian shore crabs significantly affected predictions of abundance, whereas monitoring data did not. When survey data were omitted, abundance estimates were unchanged over time, but when they were included, the model predicted an increased abundance in 2012. All 3 data sets for the Asian shore crab significantly affected estimates of species coverage; surveys had the biggest influence, increasing range size by 4097.25 km2. For the catadromous Chinese mitten crab, ecological monitoring data collected in freshwater shortly after the original sighting significantly shaped model estimates for abundance and documented the establishment phase of the mitten crab in an area outside the spatial scope of the surveyed resource users. However, the survey data significantly enlarged mitten crab range-size estimates by 6498.01 km2. By demonstrating that data integration produced an image of the invasion process that would not have emerged had we used any 1 method individually, model results provide evidence for the advantages of an interdisciplinary approach. 相似文献
309.
Introduction: With the significant number of motor-vehicle fatalities occurring on the nation’s roadways in recent years, there exists a need to integrate a more complete range of data sources, available at a regional or statewide level, to effectively evaluate existing safety concerns and quantify their impacts. Crash data alone does not provide ample crash-associated citation, injury, and roadway characteristics; therefore, a more cohesive dataset is required to accurately and completely analyze the true impacts of motor-vehicle crashes. Previously developed strategies linked crash data with citation and roadway inventory data to enhance the identification and optimization of highway safety strategies. Method: The main objective of this research focused on developing a new deterministic linkage between crash and Emergency Medical Services (EMS) data, by utilizing the Massachusetts Crash Data System (CDS) and the Massachusetts Ambulance Trip Record Information System (MATRIS). Results: After several iterations of match criterion, the validated linkage successfully matched 58.3% of MATRIS records (containing an Injury Cause of Motor Vehicle Crash) to a CDS person record (55011 linked pairs, between 2014 and 2016). The data linkage provided significant insight into injury trends in several highway safety emphasis areas such as roadway departure, speeding-related, and distraction-affected crashes. The findings from this research are twofold: (1) an established process for linking previously separate data sets, and (2) a mechanism for analysis that provides decision-makers and safety professionals with a better measure of crash outcomes. 相似文献
310.
The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method. 相似文献