测定化学需氧量的新型分光光度法

研究了一种测定化学需氧量(COD Mn)的新型分光光度法。试验结果表明,该法简便快速、准确,精密度高,并且通过与国标法测定结果对比后确定该方法可用于自来水、饮用水等多种水体中COD Mn的测定。     

基于变精度相容粗糙集的作战装备消耗预测研究

目的提升预测精度,提高作战装备保障部队的保障能力和保障水平,从而获得更高的军事经济效益。方法通过将变精度粗糙集和相容粗糙集相结合,研究实际保证任务的特点,以飞机装备为例,深入分析航空兵部队在不同环境、不同地区、不同战损等条件下执行任务所消耗的作战装备数量,减少不同因素之间的相互影响所产生的数据噪声。结果当在高原、沙漠地区执行战时装备保障任务时,该项作战装备消耗量大;在沿海地区执行战时装备保障任务时,该项作战装备消耗量小;在平原地区执行战时装备保障任务时,该项装备消耗量小甚至无消耗;在平原地区执行战时装备保障任务时,该项装备为高消耗。结论此方法有利于加强对战时装备预测的精准度,大大节省了装备的物流成本。     

环境实验室分析数据质量控制技术

文章所论述的实验室分析数据的质量控制措施主要是通过对分析方法“适用性”的验证、质控考核以及± 2S单值连续控制图相结合的方法进行的。该方法可提高测试数据的精度和稳定性 ,也可提供全过程监测数据的误差范围。既适用于小批量单一水质指标的测试分析 ,也适用于大批量且水质浓度变化幅度较大的情况。避免了因环境因素变化而采用其它控制图带来的不便和困难。使用该质控技术可获得准确、稳定的分析数据     

On ranked set sampling for multiple characteristics

We consider the selection of samples in ranked set sampling when several attributes of each sample are of interest. We describe approaches that have appeared previously in the literature and present a novel method that seeks to achieve samples that are nearly balanced with respect to the ranks of all attributes. This method is shown to result in very little loss of precision compared to problems in which only a single sample attribute is of interest.     

原子吸收法测定水中镉的质量控制指标研究

通过全国多家实验室的大量监测数据,研究分析了镉测定的质量控制指标,并与《水质镉的测定双硫腙分光光度法》（GB/T 7471-1987）和《环境水质监测质量保证手册》（第二版）进行了比较,旨在为环境监测工作提供质量控制依据和质量控制指标。研究表明,标准样品的精密度质量控制指标范围：RSD≤5.0%和RSD’≤8.0%;准...     

Comparison of data from two vegetation monitoring methods in semi-natural grasslands

Two vegetation-monitoring methods were compared: subplot frequency analysis (SF) and visual estimation of percentage cover (VE). Two independent observers collected data from two semi-natural, species-rich grasslands on three different occasions during the growth-season. During the last data collection period, survey times were also recorded. The two different data sets from the two methods were compared using partial Redundancy Analyses. The purpose of the comparison was to identify the method that explains most of the relevant variation in biodiversity-monitoring (inter-and intra-site variation), and the variation irrelevant when evaluating data (systematic inter-observer variation and variation due to phenological changes). Compared with VE data, more variation in SF data could be explained by spatial variables, while less variation depended on the observer and time of year surveyed. SF also found more species per plot but took on average five times longer to complete than VE. In conclusion, the different methods are suitable for different purposes: SF is more suitable for purposes demanding high accuracy and high precision, such as long-term biodiversity-monitoring when the identification of small changes has high priority, while VE might be more suitable for a one-time mapping of a large area.     

CODcr 5分钟快速测定法与国家标准方法对比试验

国家标准方法中重铬酸钾法测定化学需氧量,准确度高,但操作时间长,试剂使用量大,耗电耗水.采用5分钟快速测定法后能大大缩短测定时间,同时能耗低.通过对比试验表明,5分钟快速测定法具有较好的抗氯性,精密度及准确度均能达到要求,且具有成本低特点,证明了方法的可行性,特别适于污水处理厂等需频繁监测点的快速测试.     

Effect Of Reagent (Dye) Addition In Wet Chemical Method Of Sulfur Dioxide Determination In Ambient Air

For measurement of sulfur dioxide (SO₂) in ambient air, the United States Environment Protection Agency (US EPA) had recommended the PRA dye-based colorimetric method as a reference technique. The method has been developed and applied in many countries for a longtime; however information regarding the sensitivity of the method with respect to sampling and analysis conditions is not available. Collaborative studies conducted in some of the South East Asian countries indicated substantial variations (of the order of 50%) in the measured concentrations against the true values. It was observed that dye used for color development plays an important role and even a slight variation in the way the dye solution is prepared can cause substantial variation in the measured SO₂ concentration. Because a major objective of air quality measurements is to relate air pollution concentration to the effects of air pollution, it is important that the method used should yield accurate levels of the pollutant, so that appropriate management plans can be devised and implemented effectively. In the present investigation, therefore, the role of dye used in SO₂ monitoring method has been highlighted. Different makes of dyes prepared in different modes were used to study the variation in the measured SO₂ concentration levels. Specifications of all the dyes were also tested. Need for use of certified reference material (CRM) for SO₂ has also been emphasized.     

影响水体中营养盐分析测定准确性因素探讨

对影响水体中营养盐分析测定准确性的各因素进行了详细深入地探讨和分析,并通过实验室验证实验对盐效应影响营养盐分析测定准确性方面进行了首次界定,明确地给出了盐度变化是否会对硝酸盐分析测定产生影响以及其影响程度,并首次最终界定盐度范围。将实验结果应用到实际监测工作中,取得了良好的预期效果,为国家海洋局节能减排专项的顺利实施作出了直接贡献。     

基于性能退化数据分析的训练装备精度保持性评估

目的对训练装备的精度保持性评估问题进行专门研究。方法跟踪监测训练装备使用过程中精度的退化情况,并计算出每个监测时刻训练装备的综合精度指数,预测训练装备失效的寿命值。结果通过精度指数与时间的回归模型,分别得到装备的失效水平和所预测的失效寿命T',以此为基础评估训练装备的精度保持性。结论训练装备的精度保持性是用户关心的重要质量指标,对在训练装备使用过程中获取的成效有直接影响,精度保持性评估结果还是用户确定合理精度调整及训练装备大修周期的重要参考依据。