Estimating the volatilization of ammonia from synthetic nitrogenous fertilizers used in China

Although it has long been recognized that significant amounts of nitrogen, typically in the form of ammonia (NH(3)) applied as fertilizer, are lost to the atmosphere, accurate estimates are lacking for many locations. In this study, a detailed, bottom-up method for estimating NH(3) emissions from synthetic fertilizers in China was used. The total amount emitted in 2005 in China was estimated to be 3.55 Tg NH(3)-N, with an uncertainty of ± 50%. This estimate was considerably lower than previously published values. Emissions from urea and ammonium bicarbonate accounted for 64.3% and 26.5%, respectively, of the 2005 total. The NH(3) emission inventory incorporated 2448 county-level data points, categorized on a monthly basis, and was developed with more accurate activity levels and emission factors than had been used in previous assessments. There was considerable variability in the emissions within a province. The NH(3) emissions generally peaked in the spring and summer, accounting for 30.1% and 48.8%, respectively, of total emissions in 2005. The peaks correlated with crop planting and fertilization schedules. The NH(3) regional distribution pattern showed strong correspondence with planting techniques and local arable land areas. The regions with the highest atmospheric losses are located in eastern China, especially the North China Plain and the Taihu region.     

基于半参数面板数据模型的江苏省经济增长与水污染排放关系实证研究

本文以江苏省为研究区域,采用1990—2013年江苏省市级面板数据,基于单位根检验和面板协整检验,运用可拓展的随机性环境影响评估模型(STIRPAT)和参数、半参数固定效应回归方法,对经济增长与工业COD排放之间的关系展开研究。研究发现,江苏省经济增长与工业COD排放之间存在倒U形曲线关系,即全省工业COD排放随经济的发展呈现先增长后降低的趋势,同时人口增长对水污染物排放影响很大,二者之间的环境库兹涅茨曲线表明了经济持续发展能够协调并能解决其与水污染排放之间的困境。本研究丰富了社会经济发展与水污染关系在市级尺度层面的实证研究,为\"十三五\"期间江苏省水污染治理提供了政策依据。     

SDG-based HAZOP analysis of operating mistakes for PVC process

As modern chemical plants are becoming more complex and bigger in scale, the associated chance of things going wrong is also increasing rapidly. Due to the flammable, explosive, toxic and corrosive nature of chemical process, any single accident may trigger a major catastrophe that brings tremendous environmental, social and economical loss. In order to prevent any accident from happening, hazard and operability (HAZOP) analysis has been brought in to monitor chemical process and provide early warning for signs of accident. However, most existing HAZOP is carried out manually, and there are always obstacles in terms of cost overrun and incompleteness of the analysis. To address the difficulties in current HAZOP method, this paper proposes a signed digraph (SDG)-based HAZOP analysis method. It is used to identify the most likely operating mistakes that may cause certain process variable deviating from its normal value, which is the main source of safety concern. A case study on polyvinyl chloride (PVC) plant is presented to demonstrate the effectiveness of SDG-based HAZOP analysis method in providing complete analysis result.     

事故致因的突变模型

在众多论述伤亡事故致因的理论中，都没有解释为何系统元素的连续变化引起系统状态的突变（事故），以及人、物因素在这种突变过程中的作用。本文引入突变理论这一数学工具，指出系统内某些元素的连续变化导致系统状态的突然改变，较好地解决了这个问题，通过建立事故致因突变模型，提出了提高系统安全性的原则。     

烧结烟气应用电子束脱硫脱硝技术之利弊

介绍了电子束辐照烟气脱硫技术的原理、工艺流程、主要设备及其作用;中国工程物理研究院1.2万m^3/h电子束脱硫脱硝试验装置及试验结论;成都热电厂30万m^3/h脱硫示范装置的设计参数、运行情况;综合分析了烧结烟气脱硫应用电子束辐照烟气脱硫脱硝技术之利弊,认为烧结烟气脱硫应用电子束辐照烟气脱硫技术不失为一个可供选择且可行的技术.     

基于金相分析技术的煤矿火灾事故调查试验研究

通过对矿井火灾现场特性的分析,根据金属材料的特点,提出利用金相鉴定技术进行矿井火灾事故调查的新方法,试验测定得出高温作用下40号钢和铸铁的金相组织和硬度的动态变化规律.试验结果表明,不同加热温度条件下,40号钢冷却后具有不同的金相组织,其硬度随受热温度的升高迅速下降;在相同加热温度不同受热时间条件下,40号钢的金相组织与硬度变化不明显.铸铁的硬度随加热时间的增加呈下降趋势,其金相组织也有较明显的区别.根据矿井火灾后降温较为缓慢的特点,提出灰口铸铁与白口铸铁相互转变的方向性.因此,矿井火灾事故调查可以对受到火灾破坏的金属构件的金相组织的观察和硬度测定,来\"反推\"出该部位在火灾时曾受过的最高温度以及持续时间,从而可推断火灾的蔓延情况,为认定起火原因和起火位置提供技术支持.     

钢铁联合企业氮氧化物排放研究

以某钢铁联合企业氮氧化物(NOx)主要固定排放点源为研究对象,对其2010年NOx排放情况进行调研,核算NOx排放量及各生产环节各生产设备的NOx排污系数.同时,结合目前国内外NOx减排控制技术与各厂减排潜力,提出适用的NOx减排控制管理措施及建议,为“十二五”期间钢铁企业进一步开展NOx减排控制工作提供思路和途径.     

移动式颗粒床除尘器最佳入口风速下的阻力计算

分析论述了ＹＸＫＣ型除尘器在最佳入口风速下的阻力计算方法及其影响，指出了进一步研究和改进设计的方向与途径。     

基于RS和GIS的长江安庆段岸线资源评价

应用遥感影像结合GIS相关技术对长江安庆段岸线进行解译、分类，查清长江安庆段岸线资源分类长度，并采用岸前水深和岸线稳定性两个评价指标对岸线资源进行分等评价，兼顾岸前航道水域宽度和后方陆域场地条件两个限制性因素，综合确定岸线条件的优劣。评价结果：长江安庆段岸线总长度为249．6km，一级、二级优良岸线62．4km，三级岸线187．2km；开发条件较好的岸线有周家湾一套口、沟口-老湖塔和谭家沟-马船沟三段。最后结合安庆市经济发展背景、区位条件对安庆沿江岸线资源开发分段提出若干建议。     

复杂电磁环境仿真软件中的大地形文件传输技术研究

为了提高仿真速度,仿真软件一般采用多台计算机进行协同工作,首先搭建一套电波传播仿真并行系统,该系统能够导入地理信息,并在导入的地图上进行电磁辐射源建模及电磁环境仿真工作。但是,对于一些很大的地形,其海量的三维地形数据的传输时间过长,这加大了总的仿真等待时间。所以为了综合利用多台计算机的资源优势,提出使用BitTorrent方式,使得服务端与客户端的计算机均可以为地形文件的传输做贡献,极大减少了地形文件传输时间,可以从侧面提高仿真工作的效率。