API法在城市大气环境质量评价中的应用

采用空气污染指数API法对绵阳市2008年大气环境质量进行评价。结果表明,该市空气质量达到了国家二级标准,影响空气质量的主要污染物为可吸入颗粒物（PM10）,主要污染时间为1、2、3、5、12月,影响因素为气象和人为活动。建议采取优化产业结构、改造锅炉和燃烧设备、大力发展和推广使用清洁能源、加快城市绿化建设等污染防治对策。API法与其他评价方法相比,可以准确地揭示大气污染程度,是一种简便、直观且可靠的评价方法。     

天津市主要交通道口二氧化硫和氮氧化物的监测与分析研究

随着经济的增长与城市化的扩张,交通堵塞及机动车气体排放导致的城市道路交通性污染日益严重,成为国家主要的环境问题[1].以天津为例,我们选择了具有代表性的四个交通路口.采用连续监测的方法,对空气中的主要交通性污染物氮氧化物和二氧化硫的含量进行了监测分析.结果表明,海光寺氮氧化物污染最严重;其中二氧化硫浓度变化较为平稳通常,氮氧化物波动较大,车流量增加氮氧化物浓度增加,但是车流量与二氧化硫浓度影响较小.距离交通路口越远,氮氧化物的浓度越低.     

上海市浦东环境空气质量预报模式及环境状况探讨

将浦东新区空气自动监测系统监测数据与上海市空气质量日报数据进行比对 ,考察两者之间的定量关系 ,以简便的方法建立浦东环境空气质量预报模式 ,了解空气污染物在上海市区与浦东区域的分布状况差异 ,探讨造成差异的原因。     

SIMULATING SOIL WATER RECESSION COEFFICIENTS FOR AGRICULTURAL WATERSHEDS1

ABSTRACT: The antecedent precipitation index (API) has been a useful indicator of soil moisture conditions for watershed runoff calculations, and recent attempts to correlate this index with spaceborne microwave observations have been fairly successful. The prognostic equation for soil moisture used in some of the atmospheric general circulation models (GCM) together with Thomthwaite-Mather parameterization of actual evapotranspiration leads to API equations. The recession coefficient for API is found to depend on climatic factors as contained in potential evapotranspiration and to depend on soil texture as reflected by field capacity and permanent wilting point. A recently developed model for global insolation is used with climatological data for Wisconsin to simulate the annual trend of the recession coefficient. Good quantitative agreement is shown with the observed trends at Fennimore and Colby watersheds in Wisconsin. This study suggests that API could be a unifying concept for watershed and atmospheric general circulation modeling.     

MODIS气溶胶光学厚度对城市空气质量的指示

空气污染指数API(Air Pollution Index)是关系大众生产生活的一个重要指标,论证了一种由MODIS(中分辨率成像光谱仪)反演的气溶胶光学厚度产品AOT(Aerosol Optics Thickness)预报空气质量的方法,即依据API的分级标准,将API用特定的步长分组,再把各组的AOT和API均值建立相关模型,并用该模型来预测空气质量指数,经验证,预测值和实际值之间的精度为77.59%,基本达到业务运行的要求。     

基于天地图API的地质灾害管理信息系统研究与应用

在通过天地图API获取基础地理信息并辅以地质灾害专题数据的基础上,研究了移动GIS、Web API、LBS等技术的融合运用,结合地质灾害业务管理流程,设计开发出一套地灾管理系统。根据应用环境不同系统分为移动终端和指挥管理平台两套子系统,移动终端主要实现灾点现场调巡查记录、业务分析、速报及数据上传,指挥管理后台主要实现数据分析、任务指派和信息管理等功能。应用实例中针对移动GIS端与Web端的数据管理和交互反馈作出评述,并就未来应用方向作出展望。     

上海市空气质量季节变化及高污染案例分析

通过对上海市近4～5年环境空气质量监测数据的分析,探讨了上海市空气质量季节变化规律。对三次典型的高污染案例进行了分析,并从改善空气质量和加强人体保护方面提出了对策建议。     

铁岭市空气日报及预报的相关性研究

本文采用了空气污染指数进行评价空气质量,确定铁岭市空气质量日报、预报。根据空气污染指数值确定空气质量污染程度,最后采用数据统计方法对日报、预报的结果进行检验,检查两个样本均值之间是否有显著性差异。     

重庆市主城区气象要素与空气质量相关性研究

基于重庆主城区2010-2012年逐日的气象要素和大气环境质量监测数据,对气象条件与空气污染指数(API)进行相关性研究,分析气象条件影响空气质量的机制及协同作用,明确显著影响空气质量的气象要素。结果表明,当天的空气质量与前一天的空气质量相关性非常显著;各气象要素之间存在明显的协同作用,共同影响主城的空气质量;主城空气质量与大部分气象要素之间存在着相关性。其中空气污染指数与降雨、风速的相关性尤为密切。以期本研究成果能为重庆蓝天行动提供技术支持。     

Importance of accounting for the piping system and boundary conditions in determining the maximum surge pressure following heat-exchanger tube-rupture

Shell-tube type heat exchangers are often used to exchange heat between a high-pressure fluid and a low-pressure fluid, and the pressure difference between the two fluids could be significantly high. If the difference in the design pressure between the low-pressure (LP) and high-pressure sides is greater than that covered by American Petroleum Institute (API 520 and 521) 10/13^th rule, dynamic analysis is required to ascertain that the maximum surge pressure that could be reached does not compromise the integrity of the LP side of the exchanger. API guidelines also notes that attention should also be given not only to the shell-side of the heat exchanger under evaluation, but also to the “upstream and downstream systems” This paper offers further insight into the importance of including the surrounding piping systems around the subject heat-exchanger where a tube-rupture scenario is considered, and also directs attention to the importance of correctly specifying the appropriate boundary conditions (B.C.) at the far ends of both the upstream and downstream piping systems. It demonstrates the effects of specifying different B.C. on the maximum pressure surge via a case study of a hot separator vapour condenser in a bitumen hydrotreating unit, where the process fluid on the tube-side is a vapour–liquid mixture at 9660 kPa(g). The vapour mass fraction of the process fluid is approximately 0.5, and is mostly hydrogen. The fluid on the LP side is cooling water connected to the plant supply and return cooling systems as well as another adjacent low pressure condenser. The design pressure for the cooling water piping system and the adjacent condenser is 1380 kPa(g).