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131.
结合普光气田地面集输工程防雷工作的开展,就如何解决山区土壤电阻率高和电力系统防雷,如何提高电力、通讯、SCADA和RTU等自控系统的可靠性、稳定性等方面进行了分析、总结,并根据工作实际提出了建议。  相似文献   
132.
多尺度环境空气质量预报业务产品测试研究   总被引:1,自引:1,他引:0  
为了探讨NAQPMS数值模式预报产品及其他预报业务所需产品在国家-区域-城市不同尺度单位的有效使用率、重污染过程中的作用,以及不同地区(城市)预报业务需求及作业产品需求偏差,选取17家单位进行测试研究。分析数据显示:15类参与研究产品均为各省市监测中心空气质量日常预报业务的开展作出了重要贡献,NAQPMS数值预报产品准确率最高可达到84.72%,省会城市准确率略低,总体平均可达50.21%,重污染过程的平均捕捉准确率为52.33%;研究测试产品在各尺度的获取时间均可控制在2.5 h左右。研究结果表明,指导产品能基本反映污染物形成、发展及变化趋势,明确不同地区城市预报业务需求及产品偏差,在PM_(2.5)和O_3预报准确率和重污染过程捕捉预报结果偏低等方面有待加强。  相似文献   
133.
多元回归-紫外分光光度法同时测定硝基苯类化合物   总被引:2,自引:0,他引:2  
对多元线性回归、多元逐步回归和岭回归三种方法应用于硝基苯类五元体系进行定量分析的结果进行了比较研究,结果表明,对于所涉及的组分光谱重叠严重的病态的混合体系,多元逐步回归和岭回归间接校正都是合适的算法,总平均相对误差分别为3.84%和3.00%.  相似文献   
134.
基于GIS的珠三角区域空气质量时空演化分析模型研究   总被引:1,自引:1,他引:0  
利用广东省环境信息GIS综合发布平台发布的2005—2010年间珠三角区域范围内空气质量日报中空气质量等级数据,采用网格化分析、空间统计分析、专题图分级渲染模型,对珠三角区域的空气质量时空演化特征和影响因素进行研究,结果表明各周期年度珠三角区域网格空气质量频数统计上近似呈正态分布,近5来空气质量空间分布形态由以东莞、佛山为污染中心的哑铃形向以佛山中部为中心并且长轴为西北-东南向的椭圆形演化。  相似文献   
135.
A major question in global environmental policy is whether schemes to reduce carbon pollution through forest management, such as Reducing Emissions from Deforestation and Degradation (REDD+), can also benefit biodiversity conservation in tropical countries. We identified municipalities in Brazil that are priorities for reducing rates of deforestation and thus preserving carbon stocks that are also conservation targets for the endangered jaguar (Panthera onca) and biodiversity in general. Preliminary statistical analysis showed that municipalities with high biodiversity were positively associated with high forest carbon stocks. We used a multicriteria decision analysis to identify municipalities that offered the best opportunities for the conservation of forest carbon stocks and biodiversity conservation under a range of scenarios with different rates of deforestation and carbon values. We further categorized these areas by their representativeness of the entire country (through measures such as percent forest cover) and an indirect measure of cost (number of municipalities). The municipalities that offered optimal co‐benefits for forest carbon stocks and conservation were termed REDDspots (n = 159), and their spatial distribution was compared with the distribution of current and proposed REDD projects (n = 135). We defined REDDspots as the municipalities that offer the best opportunities for co‐benefits between the conservation of forest carbon stocks, jaguars, and other wildlife. These areas coincided in 25% (n = 40) of municipalities. We identified a further 95 municipalities that may have the greatest potential to develop additional REDD+ projects while also targeting biodiversity conservation. We concluded that REDD+ strategies could be an efficient tool for biodiversity conservation in key locations, especially in Amazonian and Atlantic Forest biomes. Identificación de Áreas en Brasil que Optimizan la Conservación del Carbono del Bosque, Jaguares y la Biodiversidad.  相似文献   
136.
生态资源破坏经济损失计量中概念和方法的规范化   总被引:15,自引:0,他引:15  
本文研究了在生态资源破坏的经济损失计量中与概念和方法的规范化有关的问题。它们依次是:生态资源的多价值性及价值概念系统;用于生态资源破坏经济损失计量的两种计算结构;在资源价值型计算结构中生态资源破坏量和资源的单位功能价值的确定;在核算型计算结构中生态资源破坏对灾变的影响权的确定,以及生态破坏诱发的灾害对整个经济社会系统的冲击性影响。  相似文献   
137.
The European Union EU project PROBASE hasexplored a range of possible multi projectstandardised benchmarks as a way ofencouraging projects under Joint Implementation (JI) and the Clean Development Mechanism (CDM)by minimising transaction costs. The aim ofthis paper is to examine the environmentalintegrity of the use of standardisedbaselines and to explore the role ofadditionality. The environmental integritydepends on the uncertainty in emissionreductions, which was estimated bygenerating scenario baselines and comparingthese with the standardised baselines. Thishas allowed a comparison of selected multiproject baselines with the envelope ofuncertainty on the reductions. The projectsincluded a range of electricity supply,heat sector, cogeneration and methane(CH$_{4}$) projects in different countries. Theanalysis showed that the key uncertaintieswere in the technology fuel selection inthe baseline, the continued additionalityof the project emission reductions,uncertainties in some project emissions(e.g. spinning reserve emissions for wind)and data uncertainties. The effect on theestimation of reductions was in the range±12% to ±46% for the electricityprojects and from ±19% to ±57%for the heat and Combined Heat and Power CHP sector projects.Comparison with the envelope of uncertaintyfor the range of projects showed that multiproject electricity sector baselines whichhave been weighted or use high technologyperformance benchmarks (e.g. Organization for Economic Cooperation and Development OECD)can provide conservative estimates buttheir general nature can lead to variationsbetween countries. We would recommend thatthe country-specific context must be takeninto account so that standardised baselinesfor the electricity sector are generated onthe basis of country specificcharacteristics, the project type, andwhether it provides new or existing demand.The conservative scenario produced shouldthen be weighted. Whereas weightings havebeen applied to account for uncertaintiesor to bias towards renewables, we havesuggested a weighting factor of 25% on theelectricity baseline for large projectsbased on an analysis of the effect ofnon-additionality on emission reductionuncertainty. For heat projects, theappropriate benchmark is a technology/fuelbenchmark which is deemed relevant for theheat sector in that (part of the) country.Again we suggest that a weighted sectorbaseline is required to take account of theuncertainties. These recommendations applyto large projects only for a 10-yearcrediting lifetime.  相似文献   
138.
介绍了由普通环境质量报告快速制作成声像报告的主要过程,并介绍了如何利用Powerpoint软件与其他常用软件的配合来综合多媒体技术快速制作环境质量声像的报告,对相关软件使用的关键步骤给予了详细说明,并根据经验提出了编制的注意事项。  相似文献   
139.
Ambient observations have indicated that high concentrations of ozone observed in the Houston/Galveston area are associated with plumes of highly reactive hydrocarbons, mixed with NOx, from industrial facilities. Ambient observations and industrial process data, such as mass flow rates for industrial flares, indicate that the VOCs associated with these industrial emissions can have significant temporal variability. To characterize the effect of this variability in emissions on ozone formation in Houston, data were collected on the temporal variability of industrial emissions or emission surrogates (e.g., mass flow rates to flares). The observed emissions variability was then used to construct regionwide emission inventories with variable industrial emissions, and the impacts of the variability on ozone formation were examined for two types of meteorological conditions, both of which lead to high ozone concentrations in Houston. The air quality simulations indicate that variability in industrial emissions has the potential to cause increases and decreases of 10–52 ppb (13–316%), or more, in ozone concentration. The largest of these differences are restricted to regions of 10–20 km2, but the variability also has the potential to increase regionwide maxima in ozone concentrations by up to 12 ppb.  相似文献   
140.
循环流化床锅炉(CFB)脱硫除尘系统复杂,操作不当容易导致大气污染事故的发生。通过对CFB锅炉多点排放明大气污染因子及其在大气中的扩散分析,建立了多点排放时SO2和总悬浮物颗粒(TSP)的大气环境污染的风险预测模型。模型结果较好地反映了CFB锅炉风险排污的影响因素及其环境容量的限值要求,这对于合理控制风险排污条件,加强现有CFB的运行管理是必要的。  相似文献   
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