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气相色谱仪检测器的灵敏度和检测限测量结果不确定度的评定 总被引:3,自引:0,他引:3
依据JJF1059-1999《测量不确定度评定与表示》评定了气相色谱仪检测器的主要技术指标灵敏度和检测限测量结果的不确定度。分析了各不确定度分量,建立了评定灵敏度、检测限测量结果不确定度的数学模型,并计算了其测量结果的扩展不确定度。 相似文献
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对非均匀梯度尿液分析仪测量不确定度进行评定。分别采用对称区间不确定度评定方法、选择校准点左右两侧分辨力较大者进行不确定度评定的方法、不对称区间不确定度评定方法对非均匀梯度尿液分析仪测量不确定度进行评定。采用常规的对称区间不确定度评定方法所得出的置信区间左右对称,不符合这类仪器低浓度范围分辨能力高于高浓度范围分辨能力的特性。如果选择校准点左右两侧分辨力较大者进行不确定度评定,虽较为稳妥,但其置信区间宽,不确定度偏大,测量结果准确度偏低。而通过不对称区间不确定度评定方法所得出的置信区间,左侧比右侧窄,且与仪器梯度相符,适合用于非均匀梯度尿液分析仪测量不确定度的评定。 相似文献
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依据JJF1059-1999《测量不确定度评定与表示》,评定了液相色谱仪检测器最小检测浓度测量结果的不确定度。分析了各不确定度分量,建立了评定最小检测浓度不确定度的数学模型。检测器最小检测浓度测量结果的相对扩展不确定度为7.1%(k=2.53)。 相似文献
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评定燃烧氧化-非分散红外吸收法测定水中总有机碳的测量不确定度。根据JJF1059.1—2012《测量不确定度评定与表示》、CNAS-GL006—2019《化学分析中不确定度的评估指南》,该测量方法的不确定度来源主要有标准物质、溶液配制、校准曲线拟合、测量重复性。对各不确定度分量进行评定,最终合成得到测量结果的相对标准不确定度为1.34%,水样总有机碳质量浓度测定结果表示为(48.28±1.30)mg/L(k=2)。测量重复性是影响测量不确定度的主要因素,校准曲线拟合、标准物质的影响较小。 相似文献
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室内空气中挥发性有机化合物污染及检测方法 总被引:8,自引:0,他引:8
室内空气中挥发性有机污染物的释放严重影响了室内空气质量,本文较详细的叙述了这些有机污染物的来源、种类及处理方法等,并对空气中VOCs的采集和检测方法作以介绍,阐述了不同机制的热解吸仪与气相色谱联用时的优缺点及其应用. 相似文献
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Maria Trancoso Ana Sousa Filomena Mouro Maria C. Freitas Susana Almeida Nuno Canha 《Accreditation and quality assurance》2012,17(2):199-206
In recent years, the indoor air quality has been studied more frequently due to an increasing concern within the scientific
community on the effects of indoor air quality upon health. The indoor air quality studies of schools have a large impact
in both health and educational performance of children since they constitute a sensitive group with higher risk than adults,
particularly vulnerable to pollutants due to their undeveloped airways. A total of 14 basic schools located in Lisbon city,
Portugal, were selected for sampling the total particulate matter (TPM) by passive deposition into polycarbonate filters and
to assess the indoor air quality. Compared to automatic samplers, this passive sampling method represents an easier and cheaper
way to assess several indoor air quality environments with no interference in the classroom activities. The procedure was
performed on four different campaigns during 2009–2010. The filter loads were measured by gravimetry with a 0.1-μg sensitivity
balance and, afterwards, the TPM water-soluble ions content was assessed by ionic chromatography (Cl−, NO3
−, PO4
3− and SO4
2−); flame absorption (Na+, K+, Mg2+ and Ca2+). The performance characteristics of the methods, namely specificity, limit of detection, limit of quantification, working
range, precision and trueness were evaluated. Measurement uncertainty was expressed in terms of precision and trueness. Precision
under intralaboratory reproducibility conditions was estimated from triplicate analysis. The trueness component was estimated
in terms of overall recovery using the reference material SPS-NUTR WW2 Batch 107, from Spectrapure Standards, Oslo, Norway,
for anions and the certified reference material CRM 1643e, from NIST, Gaithersburg, MD for cations. Measurement uncertainty
of the results obtained with the methods described in this work fulfilled the relative differences (RD) defined by the anion−cation balance in the extraction solutions of the particulate matter. Target RD values were defined: RD < 0.05. 相似文献
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Björklund J Isetun S Nilsson U 《Rapid communications in mass spectrometry : RCM》2004,18(24):3079-3083
Gas chromatography/ion trap mass spectrometry with in-source ionization and dissociation was used in positive-ion chemical ionization (PICI) mode for the determination of organophosphate triesters in indoor air. These compounds are widely used as additive flame retardants and plasticizers in different types of materials and have become ubiquitous pollutants in indoor environments. When using collision-induced dissociation in PICI mode the fragmentation of the organophosphate triesters can be performed in a more controllable way than in electron ionization (EI) mode. The developed selected-reaction monitoring method provided high selectivity for the investigated compounds. For 8-h air measurements (corresponding to 1.5 m3 of sampled air) the limit of detection of the method was determined to be in the range 0.1-1.4 ng m(-3), which is comparable with nitrogen-phosphorus detection and about 50-fold lower than when using EI in selected-ion monitoring mode. The presented method was applied to samples from three common indoor environments, in which a number of organophosphate triesters were identified and quantified. The dominating compound was found to be tris(2-chloropropyl) phosphate, which occurred at levels up to 0.8 microg m(-3). 相似文献
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Ruth Barro Jorge Regueiro María Llompart Carmen Garcia-Jares 《Journal of chromatography. A》2009,1216(3):540-566
This article reviews recent literature on the analysis of industrial contaminants in indoor air in the framework of the REACH project, which is mainly intended to improve protection of human health and the environment from the risks of more than 34 millions of chemical substances. Industrial pollutants that can be found in indoor air may be of very different types and origin, belonging to the volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) categories. Several compounds have been classified into the priority organic pollutants (POPs) class such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/PCDFs) and related polychlorinated compounds, and polycyclic aromatic hydrocarbons (PAHs). Many of these compounds are partially associated to the air gas phase, but also to the suspended particulate matter. Furthermore, settled dust can act as a concentrator for the less volatile pollutants and has become a matrix of great concern for indoors contamination. Main literature considered in this review are papers from the last 10 years reporting analytical developments and applications regarding VOCs, aldehydes and other carbonyls, PCBs, PCDDs, PCDFs, and PAHs in the indoor environment. Sample collection and pretreatment, analyte extraction, clean-up procedures, determination techniques, performance results, as well as compound concentrations in indoor samples, are summarized and discussed. Emergent contaminants and pesticides related to the industrial development that can be found in indoor air are reviewed in a second part in this volume. 相似文献
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Garcia-Jares C Regueiro J Barro R Dagnac T Llompart M 《Journal of chromatography. A》2009,1216(3):567-597
This article reviews recent literature on the analysis of several contaminants related to the industrial development in indoor air in the framework of the REACH project. In this second part, the attention is focused on emergent contaminants and biocides. Among these chemicals, phthalates, polybrominated and phosphate flame retardants, fragrances, pesticides, as well as other emerging pollutants, are increasing their environmental and health concern and are extensively found in indoor air. Some of them are suspected to behave as priority organic pollutants (POPs) and/or endocrine disrupting compounds (EDC), and can be found both in air and associated to the suspended particulate matter (PM) and settled dust. Main literature considered for this review is from the last ten years, reporting analytical developments and applications regarding the considered contaminants in the indoor environment. Sample collection and pretreatment, analyte extraction or desorption, clean-up procedures, determination techniques, and performance results are summarized and discussed. 相似文献
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Danuta Gorlo Bogdan Zygmunt Marta Dudek Anna Jaszek Michał Pilarczyk J. Namieśnik 《Analytical and bioanalytical chemistry》1999,363(7):696-699
Practical application of Solid-Phase Microextraction (SPME) for the assessment of the quality of indoor air is presented.
SPME was used to sample selected organic pollutants (carbon tetrachloride, benzene, toluene, chlorobenzene, p-xylene and n-decane). An SPME fiber was coated with a 100 μm film of polydimethylsiloxane. The analytes extracted were analysed with a
gas chromatograph directly coupled with a mass spectrometer (GC-MS). The method was used to assess the indoor air quality
in a few selected flats. The concentrations ranged from below detection limits to 6.9 mg/m3 for benzene depending on the flat; they were relatively high for newly built or freshly renovated flats.
Received: 14 July 1998 / Revised: 17 November 1998 / Accepted: 21 November 1998 相似文献
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对中学化学学生实验活动中产生的气体污染物进行测试,得到不同通风条件下化学实验室内部空气污染物的数据。结果表明,中学化学学生分组实验产生的主要气体污染物有苯、甲苯、甲醛、氨气等,实验过程中如不采取任何通风措施,实验室气体污染物的浓度短时间内会急剧升高,所以采取有效措施对实验室内部空气污染物进行消除是非常必要的。目前中学化学实验室配备的通风设备以桌面排风设备为主,相比于自然通风的环境,学生实验时开启桌面排风设备,能够有效降低实验产生的气体污染物浓度。 相似文献