环境监测中氯化氢测定的分析方法试验

针对国家标准《HJ/T27-1999》与《空气和废气监测分析方法》的2种氯化氢测定方法中氢化钾用不同介质进行稀释，和显色时间及试剂加入量的区别进行正交试验，得出结果。     

水中CO_2现场快速测定方法研究

通过研制一种测试管 ,能简便、快速的测定水中的CO2 。该测试管尤其适宜于现场即时监测。具有快速、简便、抗干扰能力强等特点。     

碳酸盐岩Sr同位素比值的选择性溶解及测定技术

传统的碳酸盐岩的Sr同位素比值测定由于采用盐酸溶样 ,虽然具有溶解迅速的优点 ,但同时也使非碳酸盐组分被溶解而往往导致测定值偏高 ,同时也增加了Sr分离与纯化的难度。因此 ,我们考虑用弱酸来溶解碳酸盐岩矿样 ,以改进传统方法的不足。实验中采用醋酸作为溶解介质 ,对比了不同浓度的醋酸的溶解效果 ,对较难溶解的白云岩样品作了弱酸溶解实验 ,同时比较了 2 .5mol/L盐酸和 4mol/L醋酸溶样后的测定结果和测定精度。实验结果表明碳酸盐岩Sr同位素的选择性测定技术可以使溶解对象局限于样品中的目标组分———碳酸盐岩 ,防止样品中的非碳酸盐岩组分的溶解 ,避免过多的杂质进入溶解液 ,使碳酸盐岩中的微量元素———Sr(通常含量在 10 4 — 10 5范围内 )的同位素比值测定趋于准确和可靠 ,同时也减少了杂质元素的干扰 ,便于Sr的分离与纯化。     

测定生产力中"叶绿泰a"的方法探讨

对测定生产力中"叶绿素a"的方法进行了探讨与改进,并进行了方法的验证.本方法的精密度范围为6.1%～8,4%,实验证明,本方法具有简单、快速、准确等特点.     

Impact significance determination—Back to basics

Impact significance determination is widely recognized as a vital and critical EIA activity. But impact significance related concepts are poorly understood. And the quality of approaches for impact significance determination in EIA practice remains highly variable. This article seeks to help establish a sound and practical conceptual foundation for formulating and evaluating impact significance determination approaches.It addresses the nature (what is impact significance?), the core characteristics (what are the major properties of significance determination?), the rationale (why are impact significance determinations necessary?), the procedural and substantive objectives (what do impact significance determinations seek to achieve?), and the process for making impact significance judgments (how is impact significance determination conducted?). By identifying fundamental attributes and key distinctions associated with impact significance determinations, a basis is provided for designing and evaluating impact significance determination procedures at both the regulatory and applied levels.     

超声粉碎-TOC/TN仪法直接测定污水处理厂废水中的总氮

污水处理厂废水经超声粉碎后,使用TOC/TN仪直接测定总氮。进样方式为带搅拌功能的自动进样,样品超声粉碎时间为30 min。处理前相对标准偏差小于2.35%,处理后相对标准偏差小于1.68%。处理前加标回收率为96.0%～98.5%,处理后加标回收率为94.5%～96.0%。检测限为0.050 mg/L。测定结果与国标法一致,两种方法的相对误差小于士1.3%。经t检验,两种方法的测定结果差异无统计学意义。方法简便、快速、无需复杂前处理。     

自由基测定方法进展

本文对自由基的测定方法进行综述和评价，包括电子自旋共振、高效液相色谱、化学发光、分光光度等方法，引用近十年来的文献３８篇。     

Comparison of masking agents for antimony speciation analysis using hydride generation atomic fluorescence spectrometry

A sensitive atomic spectrometric method for the redox speciation analysis of Sb in water is described. The proposed method is based on the selective generation of stibine from Sb(III) in a continuous flow system using non-dispersive atomic fluorescence spectrometry for detection. The effects of the HCl concentration on the fluorescence intensities of Sb(III) and Sb(V) were investigated. The results indicated that atomic fluorescence emission due to Sb(V) can constructively interfere with the determination of Sb(III). For the determination of Sb(III), four compounds were tested as masking agents to inhibit the generation of stibine from Sb(V). The effects of the concentrations of the masking agents and of HCl on the fluorescence signals from Sb(III) and Sb(V) were studied. The results indicated that citric acid and NaF can successfully suppress hydride generation from Sb(V). To evaluate the developed methodology and the influence of the matrix, the recovery of Sb(III) from natural water that was spiked with different Sb(III) and Sb(V) concentrations was tested.