总氮自动分析仪在地表水监测中的优势与局限研究

文章分析了总氮自动分析仪在地表水监测中的优势与局限。通过对检出限、精密度、准确度等一系列实验室质量要求进行测定发现,该法的空白较低,准确度和精密度均能达到国标要求,分析效率高,但检出限偏高,适合总氮含量较高的地表水监测,对于含量较低的地表水,还应使用传统的国标方法检测。     

Dynamic-risk-informed safety barrier management: An application to cost-effective barrier optimization based on data from multiple sources

An integrated approach for performance assessment and management of safety barriers in a systemic manner is needed concerning the prevention and mitigation of major accidents in chemical process industries. Particularly, the effects of safety barriers on system risk reduction should be assessed in a dynamic manner to support the decision-making on safety barrier establishments and improvements. A simulation approach, named Simulink-based Safety Barrier Modeling (SSBM), is proposed in this paper to conduct dynamic risk assessment of chemical facilities with the consideration of the degradation of safety barriers. The main functional features of the SSBM include i) the basic model structures of SSBM can be determined based on bow-tie diagrams, ii) multiple data (periodic proof test data, continuous condition-monitoring data, and accident precursor data) may be combined to update barrier failure probabilities and initiating event probabilities, iii) SSBM is able to handle uncertainty propagation in probabilistic risk assessment by using Monte Carlo simulations, and iv) cost-effectiveness analysis (CEA) and optimization algorithms are integrated to support the decision-making on safety barrier establishments and improvements. An illustrative case study is demonstrated to show the procedures of applying the SSBM on dynamic risk-informed safety barrier management and validate the feasibility of implementing the SSBM for cost-effective safety barrier optimization.     

大气VOCs在线监测系统测量准确性分析

基于在线气相色谱-氢火焰离子检测/质谱(GC-FID/MS)方法,在线测量116种大气挥发性有机物的性能指标(线性关系、检出限、精密度、正确度、期间正确度和期间精密度).基于在线监测系统连续7d的实际运行情况,定量评估116种有机物在实际长期运行中测量的准确性和可靠性.结果 表明,116种组分中,109种组分的线性相关...     

Conceptual Models as Hypotheses in Monitoring Urban Landscapes

Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.     

基于光纤分布式测温的污水管道入流识别方法研究

针对排水管网物探检测需断水操作和无法对管道内部实时探查的问题,建立了一种基于光纤分布式测温的污水管道入流诊断方法,实现了无干扰条件下污水管道污水和雨水入流实时监控.采用感温光缆对选择的试验管段开展了时空高精度观测(空间精度1m、时间精度1min),获得了超过118万个管道水温数据.基于解析出的管道水温时空图像,提出了基于水温温差背景噪声值的入流定位方法;确定出无外部入流影响时管道水温空间和时间温差的背景噪声值分别约为±0.2℃和±0.5℃.采用水温图像降噪处理方法,自动识别出污水管道的旱天污水接入和雨天雨水接入事件,与现场调查结果一致.因此,该方法对污水管道入流的动态识别定位具有可靠性.     

河豚毒素检测技术研究进展

对检测河豚毒素的主要方法包括生物检测方法、理化检测方法、免疫学方法、传感器方法进行了介绍,并对目前检测方法的优缺点进行比较分析。小鼠测定法是河豚毒素检测的标准方法;理化检测法方法准确,但是对设备要求高,前处理严格;免疫学方法费用较高;传感器方法是新方法,还有待进一步规范。各种检测方法都有其优缺点,河豚毒素检测时应根据要求选择方法。     

固定污染源烟气比对监测的几点思考

固定源烟气对比监测是保证自动监测数据质量的重要手段。但是,有效性审核比对监测过程中存在烟气排放连续监测系统安装不规范、手工监测抗干扰能力较差、烟气预处理效果不稳定及监测点位差异影响监测结果比对等问题。在此基础上,提出了严格规范环境监测点位的布置,针对不同的污染源确定适合的监测技术方法,研发完善的烟气预处理设施以及建立健全的自动监测质量保证体系等解决问题的对策。     

胶州湾综合监测与评价工作研究

为全面掌握环胶州湾区域生态环境状况,更好地服务于环胶州湾区域经济发展和生态环境保护,根据《近岸海域环境监测规范》(HJ 442-2008),青岛市环境监测中心站对环胶州湾区域进行了综合监测与评价,建立了环胶州湾区域陆海统筹监测评价体系,完善了胶州湾水质监测网络,摸清了环胶州湾区域直排海污染源状况及环胶州湾区域土地利用状况。针对综合监测与评价过程中存在的胶州湾污染源的排放状况掌握不全面、河流入海通量的测算不准确、环境质量的变化趋势预测不能实现的问题,提出了加强入海河流监测、实行陆源污染物总量控制管理、建立自动监测站等对策建议。     

我国饮用水卫生标准的变化与发展探讨

通过对我国新旧《生活饮用水卫生标准》和国外饮用水卫生标准的差别比较,结合对国际上发达国家的饮用水卫生标准发展趋势的探讨;表明新的《生活饮用水卫生标准》(GB5749-2006)更具先进性,与国际标准接轨;同时其可操作性更强,又与我国国情贴近。     

长沙市灰霾天气与气象因子相关性研究

根据长沙市2013年PM2.5的逐日质量平均浓度、气象地面和高空观测数据,采用SPSS方法,分析了长沙市灰霾天气发生与气象因子的关系。结果表明:长沙市区的灰霾日以西北风向为主,PM2.5浓度与风速、降水呈显著负相关,与相对湿度、大气压、平均气温相关不明显。风速越小越不利于大气污染物的扩散,在没有降水的情况下,风速达到3.5m/s以上,空气质量才有好转;弱降水对污染物的浓度不会有明显的影响,降水量在5mm以下时,污染物的浓度不会有明显的下降,但强降水对空气有净化作用明显,在不同季节,不同时段,不同天气形势下降水的稀释作用不同;长沙秋冬季边界层稳定性几率高达80%以上,这种稳定层结构是长沙市区各种大气污染源不易扩散的重要因素之一。