靛蓝二磺酸钠分光光度法测定空气中臭氧问题探讨

本文就靛蓝二磺酸钠（ＩＤＳ）分光光度法测定空气中臭氧（标准方法）的有关ＩＤＳ溶液的稳定性及样品测定等问题做了进一步研究,以期使标法更趋完善。     

硫脲分光光度法测定土壤和沉积物中铋（Bi）量

建立了对土壤和沉积物中铋含量进行测定的新方法——硫脲分光光度法,实验结果表明此分析方法操作简便、选择性好、灵敏度高,测试结果令人满意。     

紫外分光光度法测定水中石油类物质的有关问题探讨

对紫外分光光度法测定水中石油类物质中，有关萃取剂、萃取技术、标准曲线斜率的稳定性等进行了初步探讨。     

分光光度法测定水中游离氯和总氯曲线及加标回收问题探讨

为了解决分光光度法(HJ586-2010)在曲线绘制时存在低浓度点不显色现象,用于加标的次氯酸钠标准液不稳定且操作繁琐的现实缺陷。采用不同显色时间及取消曲线制作过程中在加入硫酸溶液前先加入约50 mL水的实验环节,并采用碘酸钾代替氯制剂进行加标回收。实验结果表明,随着显色时间的延长,曲线斜率逐渐降低,曲线的第一点吸光值始终偏低,无法取得理想的标准曲线,在取消加入约50 mL水的环节后,无论是高浓度曲线还是低浓度曲线的截距、斜率和相关系数均符合污水监测技术规范要求;碘酸钾标准溶液按照绘制标准曲线的方法加入硫酸和氢氧化钠溶液处理好以后再进行水样加标,获得的加标回收率,符合《环境水质监测质量保证手册》的要求。分析实验结果可知,显色时间不是标准曲线绘制成败的决定因素;碘酸钾和碘化钾反应时溶液的酸度高低决定了碘分子或[I_(3)]^(-)在规定时间内生成是否完全,从而决定了标准曲线绘制的成功与否;用碘酸钾溶液代替次氯酸钠溶液进行加标回收,可以解决次氯酸钠标准溶液操作繁琐且不稳定的难题。     

《水质石油类的测定紫外分光光度法(试行)》(HJ970-2018)中的问题探讨

基于新实施的《水质石油类的测定紫外分光光度法(试行)》(HJ970-2018),结合实际操作中遇到的问题,通过试验,在正己烷透光率、样品采集、萃取、脱水、吸附等方面探讨了(HJ970-2018)中发现的问题。结果表明,不同品牌不同级别的正己烷透光率有显著差异,这对石油类的测定起关键作用;样品采集、萃取、脱水、吸附可进一步改进,并给出了相应对策建议。     

GB/T 20626.3-2006标准要求和发展解析

由于我国特有的高原环境气候,电工电子产品和设备受雷电、污秽与凝露的影响,性能有较大的变化,本标准的要求目的在于增强电工电子产品和设备在高原雷电、污秽与凝露条件下的适应性能,提高电工电子产品和设备在高原特殊环境条件下的可靠性水平,规范生产、配套和使用行为准则。     

基于GB/T 29309标准的HALT测试技术分析

本文以标准GB/T 29309-2012为基础,以某款开关电源为例,对HALT试验设备、工作极限与破坏极限、试验步骤及设备运行中注意点等方面展开介绍,为电子产品可靠性测试提供相关探讨。     

GB/T5750-2006标准比色列缓冲法测定pH值的改进

本文依据GB/T 5750-2006标准比色列缓冲溶液比色法测定生活饮用水中的pH值,结合我实验室的检测经验对国标中指示剂的配制等重要环节进行了补充,并采用标准缓冲溶液比色法和玻璃电极法同时对自来水、河水、井水及矿泉水的pH值进行了测定,相对偏差在0.2%~1.3%之间,结果满意。     

新版GB/T19056电磁环境适应性要求分析

介绍了GB/T 19056新版本对汽车行驶记录仪电磁环境适应性要求,比较和分析了新旧版本在电磁环境适应性方面的的异同,重点介绍了新版标准中瞬态抗扰性脉冲的波形和参数要求,研究和探讨了标准中对产品电磁环境适应性要求的内涵.     

Application of a long-path differential optical absorption spectrometer (LP-DOAS) on the measurements of NO(2), SO(2), O(3), and HNO(2) in Gwangju, Korea

A differential optical absorption spectrometer (DOAS) technique has been applied to monitor airborne trace pollutants including NO(2), SO(2), O(3), and HNO(2) in the ultraviolet (UV) region (290-350 nm) over a 1.5 km beam path (two ways) during an intensive measurement campaign held at Gwangju, Korea (March 2002). Their mean mixing ratios (and standard deviations) were computed as 11.3 (8.8), 1.9 (1.7), 17.1 (19.3), and 0.5 (0.4)ppbv, respectively. As a means to evaluate the performance of the long-path DOAS (LP-DOAS) system with conventional point monitoring systems (PMS), correlation analysis was conducted between the two data sets. These data sets were then inspected to account for the influence of the environmental conditions on the correlation strength between the two systems, especially with respect to light level and wind speed. To facilitate the comparison, correlation analyses were conducted after dividing the data sets for those parameters into several classes. The strength of the correlations between DOAS and meteorological parameters was also examined to evaluate their effects on the DOAS performance. It was found that, among the four pollutant species, O(3) is the most sensitive to changes in meteorological conditions in relation with atmospheric mixing conditions. The overall results of our study indicate that open-path monitoring techniques can be used to effectively diagnose air quality and be substituted for the conventional point monitoring methods with the proper consideration of those parameters affecting the DOAS sensitivity (e.g., light level and wind speed).     

HB6783、GB/T5170在温湿度试验箱性能指标验收中的应用

本文简要介绍了环境与可靠性试验领域试验设备系列检定标准HB 6783、GB/T 5170。以本单位某型温湿度试验箱验收为例,详细介绍了HB 6783、GB/T 5170系列温湿度试验设备检定/检验标准在温湿度试验箱性能指标验收中的应用,通过对比应用总结,指出综合比较不同检定标准中温湿度性能指标的检定项目、方法,结合本单位产品试验需求应用,是制定温湿度试验箱性能指标验收方法的最佳途径。     

消化/剩余污泥水分扩散通量的研究

在传递理论的基础上,研究了干燥温度、污泥厚度及其种类3个主要因素对污泥水分扩散的影响,干燥温度设为30℃、40℃和50℃,污泥厚度设为1.3 cm、2.6 cm和3.9 cm,分别考察了消化和剩余两种污泥的干燥性能。利用实验数据获得两种污泥的有效质扩散系数,采用因次分析法建立了它们的水分扩散通量的准则关系式,通过实验研究两种污泥的水分扩散通量随干基含湿量的变化规律,并获得了两种污泥的水分扩散通量的经验公式。实验结果显示3.9 cm厚的消化污泥在40℃条件下的干燥效果最好。     

关于“正弦振动试验”现行国家标准与正在修订中的新版标准的解读

正弦振动试验是试验室经常采用的振动方式,对应正弦振动试验国家标准GB／T2423．10应用非常广泛。本文介绍了该标准的用途、制修订背景等,在此基础上分析了现行正弦振动试验国家标准GB／T2423．10—2008与正在修订的6B／T2423．10—201×之间的异同之处,并指明了此标准应用中的几点注意的问题。     

Ground-level ozone in the Pearl River Delta and the roles of VOC and NO(x) in its production

In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) emission controls. Nonetheless, ambient NO(2) levels in the Pearl River Delta remained high. The regional average concentrations of volatile organic compounds (VOCs) were 290 ppbC in summer and 190 ppbC in autumn. Local emissions and long-distance transportation of pollutants play important roles in the regional distribution of VOCs. Ambient O(3) production is significant in urban areas and also downwind of cities. The relative incremental reactivities (RIRs), determined by an observation-based model, showed that ground-level ozone formation in the Guangzhou urban area is generally limited by the concentrations of VOCs, but there are also measurable impacts of NO(x).