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361.
乌鲁木齐市大气硫酸盐化速率与二氧化硫浓度的相关性 总被引:1,自引:0,他引:1
对全市1989年至1991年中大气硫酸盐化速率与二氧化硫的监测数据进行了相关性研究,结果表明:除七道湾化工厂外,两项目间存在着非常显著的正相关关系.对建成区7个测点三年中83对监测数据进行了一无线性回归分析,建立了合理可行的回归方程式 相似文献
362.
针对1990年和1991年绵阳市SO_2浓度升高,尤其是1990年和1991年元月监测的SO_2浓度值更高。经研究发现监测采样时的气象条件对污染物测定值产生重要影响。 相似文献
363.
将每天TSP、SO_2两种污染物各采四次样并分别进行测定,简化为每天各采一个“日混合样”进行测定,对测定结果进行数理统计检验结果表明:测定值之间不存在显著性差异、两种方法的测值波动是由偶然因素造成的,因此,简化方法即采日混合样进行分析是一种可靠的监测方法,它适用于煤质中含硫份较低的地区。 相似文献
364.
大气污染对城市绿化植物叶片叶绿素含量的影响 总被引:8,自引:0,他引:8
研究了南阳市城市大气对该市5种常见城市绿化植物叶片叶绿素(a、b)含量比例(Ca/Cb)以及叶片叶绿素总含量(Ct)的影响。通过研究发现,污染严重的南阳卷烟厂区域植物叶片叶绿素Ca/Cb值相对较高,叶绿素总含量(Ct)相对较低;无污染的对照区域(南阳师范学院院内绿化区)植物叶片叶绿素Ca/Cb值相对较低,叶片叶绿素总含量(Ct)相对较高。通过数据分析,进一步得出了5种常见城市绿化植物抗大气污染能力的大小:女贞>大叶黄杨>月季>金叶女贞>三叶草。 相似文献
365.
Jordan faces stringent energy challenges mainly in the form of import dependence and escalating demand. The building sector accounts for 58% of total national electricity consumption and therefore plays an important role in addressing these challenges. This article investigates how energy efficiency in green buildings certified by the Leadership in Energy and Environmental Design (LEED) rating system contribute towards achieving United Nations (UN) Sustainable Development Goals (SDGs) in Jordan. Furthermore, this paper proposes a new Comprehensive Contribution to Sustainable Development Index (CCSDI) to assess the contributions of implementation of the LEED 2009 prerequisites and credits in the Energy and Atmosphere (EA) category to achieve UN SDGs in Jordan. Questionnaire surveys were conducted to obtain data. Relative Importance Index (RII) method was used to evaluate the contributions of LEED 2009 prerequisites and credits in the EA category. Results indicate a positive relationship between the LEED 2009 prerequisites and credits in category and UN SDGs 7?9 and 12?13. We conclude that our proposed CCSDI is a robust tool for assessing the contribution of energy efficiency in LEED 2009 certified green buildings towards achieving UN SDGs in Jordan. 相似文献
366.
为了探究公路施工安全事故诱因及其影响关系,基于"4M"理论和事故致因"2-4"模型,识别公路工程施工安全事故致因因素并确定模型框架,运用SPSS Modeler软件对2007~2017年426起事故进行关联规则挖掘,采取路径分析与重要度分析,构建出公路工程施工安全事故致因模型。结果表明:施工单位内外部原因共同引发公路工程施工安全事故,外部原因来源于建设单位、监理单位和勘察设计单位的安全管理缺失,而施工单位内部影响因素中,人的不安全动作、物的不安全因素、不良的生产环境和自然环境是事故发生的直接原因,无效的安全监管和作业层安全素质及能力不强是间接原因,根本原因是施工程序和技术方案存在缺陷,根源原因是决策层和管理层的安全素质及能力有待提高。该模型系统展现了工程施工项目安全事故致因因素的影响关系和重要程度,为公路工程施工安全事故预防提供指导。 相似文献
367.
The Steady State Water Chemistry Model (SSWCM) is a common method for determinations of critical loadof acid and subsequently of critical loadexceedance for lakes. One way to verify the modeloutput, is to compare with chemical indicatorssuch as pH-value, alkalinity or ANC. When themedian chemical status (as ANC) is used 65% ofthe lakes responded according to the exceedancevalue. For these the calculated exceedanceresulted in violation of the critical chemicalvalue while non-exceedance gave no violation.Since biota react on extreme conditions a morecorrect evaluation should be based on minimumvalues for the chemical indicator. This raises thefraction of lakes responding to 78%. Non-exceedance is seldom found inlakes with acid conditions. The evaluationindicates that the calculation of critical load ofacidity by means of SSWCM is very reliable. 相似文献
368.
气候变化对我国水文水资源系统的影响研究 总被引:2,自引:0,他引:2
旨在介绍气候变化对我国水文水资源系统影响研究的进展、方法、技术及其优缺点,并分析气候变暖对我国水文水资源系统的影响结果,同时提出自己的一些建议。 相似文献
369.
Gary W. Shenk Lewis C. Linker 《Journal of the American Water Resources Association》2013,49(5):1042-1056
The Phase 5.3 Watershed Model simulates the Chesapeake watershed land use, river flows, and the associated transport and fate of nutrient and sediment loads to the Chesapeake Bay. The Phase 5.3 Model is the most recent of a series of increasingly refined versions of a model that have been operational for more than two decades. The Phase 5.3 Model, in conjunction with models of the Chesapeake airshed and estuary, provides estimates of management actions needed to protect water quality, achieve Chesapeake water quality standards, and restore living resources. The Phase 5.3 Watershed Model tracks nutrient and sediment load estimates of the entire 166,000 km2 watershed, including loads from all six watershed states. The creation of software systems, input datasets, and calibration methods were important aspects of the model development process. A community model approach was taken with model development and application, and the model was developed by a broad coalition of model practitioners including environmental engineers, scientists, and environmental managers. Among the users of the Phase 5.3 Model are the Chesapeake watershed states and local governments, consultants, river basin commissions, and universities. Development and application of the model are described, as well as key scenarios ranging from high nutrient and sediment load conditions if no management actions were taken in the watershed, to low load estimates of an all‐forested condition. 相似文献
370.
Abstract Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a cost-effective basis. This paper identifies and assesses a range of options for addressing this problem. We apply the Ambient Least Cost Model and compare the economic costs of control options, then recommend the most effective sequence to realize pollution control at the lowest cost. The study finds that installing of Stage II gasoline vapor recovery system at Beijing’s 1446 gasoline stations would be the most cost-effective option. Overall, options to reduce ozone pollution by cutting vehicular emissions are much more cost-effective than options to “clean up” coal-fired power plants. 相似文献