实验室检测质量控制有效性评价方法探讨

控制检测结果质量,持续保持检测活动的有效性和检测结果的准确性,是检测实验室质量管理工作的根本目的。检测实验室质量控制方法主要有:1定期使用有证标准物质(参考物质)进行监控;2参加实验室间的比对或能力验证计划;3使用相同或不同方法进行重复检测;4对存留物品进行再检测或再校准;5分析一个物品不同特性结果的相关性。就上述几种质量控制方法而言,如何确定其评价方法是实验室面对的首要问题。目前我国相关国     

检测实验室日常检测中的质量控制探讨

质量控制是检测实验室十分重要的技术工作和管理工作.本文探讨了影响检测结果质量的因素,提出了分析常用的检测质量控制方法.     

2012年金属材料分析检测人员培训通知

为提高我国金属材料分析检测人员的技术能力,以确保金属材料检测实验室向社会提供分析检测结果的准确性和可靠性,应金属材料检测实验室以及广大的分析技术工作者的需求,北京有色金属研究总院分析测试技术研究所(国家有色金属质量监督检验中心)(NTC认可授权的权威培训机构)将于2012举办四期共12班次金属材料分析检测人员培训。     

地下水有机污染物质量监控样品检测数据质量评价EI北大核心CSCD

选取我国5家地下水污染调查检测实验室前后两年质量监控样品检测数据,按检测组分、检测样品类型和实验室检测技术能力3方面进行质量监控评价。两年内5家实验室的288件检测样品,累计5454个检测组分中各检测组分合格率为90.4%~100%,挥发性有机污染物(VOC)和半挥发性有机污染物(SVOC)样品的合格率为97.4%~99.4%,均满足地下水污染调查评价样品分析与质量控制技术要求;5家实验室VOC和SVOC样品检测的整体合格率为88.4%~100%。总体上我国地下水污染调查检测实验室的有机污染物测试能力有很大提高,检测数据准确可靠。     

天然气检测实验室质量控制方式探讨

结合天然气检测工作实际情况,对天然气检测实验室质量控制方式进行了探讨。检测实验室质量控制分为内部质量控制和外部质量控制。检测实验室内部质量控制方式有重复检测、内部比对、使用有证标准物质、检测方法中规定的内部质量控制、不确定度评定及校准曲线等;外部质量控制方式有实验室间比对和测量审核两种方式。当评价精密度控制时,可使用重复检测、内部比对、检测方法中规定的内部质量控制等方式;当评价准确度时,可使用有证标准物质;当需对检测全过程进行评价时,可采用不确定度评定、校准曲线、实验室间比对、测量审核等方式。     

地下水有机污染物质量监控样品检测数据质量评价

选取我国5家地下水污染调查检测实验室前后两年质量监控样品检测数据,按检测组分、检测样品类型和实验室检测技术能力3方面进行质量监控评价。两年内5家实验室的288件检测样品,累计5454个检测组分中各检测组分合格率为90.4%~100%,挥发性有机污染物(VOC)和半挥发性有机污染物(SVOC)样品的合格率为97.4%~99.4%,均满足地下水污染调查评价样品分析与质量控制技术要求;5家实验室VOC和SVOC样品检测的整体合格率为88.4%~100%。总体上我国地下水污染调查检测实验室的有机污染物测试能力有很大提高,检测数据准确可靠。     

计算机技术在水质检测实验室信息管理系统中的应用

介绍计算机技术在水质检测实验室信息管理系统中的应用,基于信息管理系统的总体设计思路,探讨计算机数据库技术和网络技术在排水监测站实验室信息管理系统中的应用。水质检测实验室信息管理系统是集分析检测、质量控制及实验室综合管理于一体的模块化、开放式信息平台,主要应用于水质检测流程控制、质量监测和实验室管理。对计算机技术在水质检测实验室信息管理系统建设中的应用进行分析,为水质检测实验室信息管理系统的建设应用提供解决方案。通过实验室信息管理系统建设,可以规范实验室的管理,调动实验室各种资源,提高工作效率,加大对污废水排放的监管力度。     

浅析化学检测实验室的质量控制

<正>近年来,随着人们对生命健康、产品质量的重视,化学检测实验室已成为消费品安全检测的主力军。检测质量是实验室生存和发展的保证,是衡量实验室管理能力的标尺,是为客户提供优质服务的前提。因此,如何保证检测结果的科学、公正、准确、可靠,加强和规范检测结果的质量控制,是每一个化学检测实验室必须解决的课题。质量控制是实验室为达到质量目标和质量要求所采取的技术活动,是实验室质量管理体系[1-2]的核心。国内一些学者[3-5]     

建立天然气检测实验室的技术方案

提出建立天然气检测实验室的技术方案,提供天然气质量评判基础数据。分析商品天然气、页岩气、液化天然气、压缩天然气及煤层气等5类天然气产品的主要技术指标,确定天然气检测的14种技术。综合考虑"人、机、料、法、环"几个方面,建立技术全面、管理科学、过程可控、质量可靠的天然气检测实验室,保证天然气质量检测结果准确、公正、可信。     

有证标准物质的正确使用

对于从事化学检测工作的检测实验室而言,有证标准物质(包括标准溶液,下同)是一个不可或缺的、非常重要的物质,几乎所有的检测过程均需使用标准物质。尽管许多化学检测实验室及化学检测人员非常明确地知道有证标准物质对于检测过程的重要性;但是,在实际使用有证标准物质的过程中,鲜有实验室和检测人员采用统计方法对有证标准物质的检测结果进行分析、处理。本文阐述了检测实验室应如何正确使用有证标准物质。     

铁矿石、锰矿石和铬矿石取样和样品制备技术概况

我国钢铁工业的主要原料铁矿石、锰矿石和铬矿石进口量大,对外依存度分别在80%,55%,95%以上,贸易中经常发生质量纠纷,有些质量纠纷的焦点为取样和样品制备技术。从影响样品代表性的角度概述了铁矿石(包括直接还原铁和热压块)、锰矿石和铬矿石取样和样品制备所涉及的方法标准、品质波动、样品部位、最小份样数、最小份样量、缩分方法、最小留样量和设备的技术要求,分析了取样和样品制备中存在的问题,提出了确保取样和样品制备人员能正确执行方法标准、采取有代表性样品应采取的措施。     

气相色谱法测定仓储双基发射药二号中定剂含量

 利用气相色谱法迅速分离并准确测定仓储发射药中具有安定作用的二号中定剂(二甲基二苯脲)的含量。该法与传统的溴化法比较,具有快捷、准确、直观、重复性好等特点,可以为正确评估发射药的质量等级提供可靠数据。     

使用C18固相萃取膜-色质联用定量分析饮用水中痕量多环芳烃的初步研究

参照美国EPA525.1方法,C18-固相萃取膜萃取饮用水中的有机物,利用GC/MS法鉴定多环芳烃(PAHs),使用16种多环芳烃混合标准样绘制标准曲线,以内标法对PAHs进行定量分析.采用本方法研究某水厂经过深度处理后的出厂水中的7种多环芳烃的含量,PAHs的平均回收率为94.0%～97.7%.检测限为0.001μg/L.     

Headspace solid‐phase microextraction and gas chromatographic analysis of low‐molecular‐weight sulfur volatiles with pulsed flame photometric detection and quantification by a stable isotope dilution assay

Low‐molecular‐weight volatile sulfur compounds such as thiols, sulfides, disulfides as well as thioacetates cause a sulfidic off‐flavor in wines even at low concentration levels. The proposed analytical method for quantification of these compounds in wine is based on headspace solid‐phase microextraction, followed by gas chromatographic analysis with sulfur‐specific detection using a pulsed flame photometric detector. Robust quantification was achieved via a stable isotope dilution assay using commercial and synthesized deuterated isotopic standards. The necessary chromatographic separation of analytes and isotopic standards benefits from the inverse isotope effect realized on an apolar polydimethylsiloxane stationary phase of increased film thickness. Interferences with sulfur‐specific detection in wine caused by sulfur dioxide were minimized by addition of propanal. The method provides adequate validation data, with good repeatability and limits of detection and quantification. It suits the requirements of wine quality management, allowing the control of oenological treatments to counteract an eventual formation of excessively high concentration of such malodorous compounds.     

Development and qualification of a size exclusion chromatography coupled with multiangle light scattering method for molecular weight determination of unfractionated heparin

The molecular weight of unfractionated heparin was determined by size exclusion chromatography (SEC) coupled with multiangle light scattering (MALS) detection. The SEC/MALS method determines absolute molecular weight directly from the angular dependence of scattered light intensity as a function of concentration and does not rely on molecular weight standards for column calibration. The SEC/MALS method developed at Scientific Protein Laboratories was qualified in terms of specificity, precision, robustness, and accuracy. By eliminating the requirement of well-characterized molecular weight standards derived from heparin, the present procedure represents a clear improvement over the column calibration methods used in molecular weight determination. The SEC/MALS method is suitable for routine quality control of unfractionated heparin.     

Trace level perchlorate analysis by ion chromatography-mass spectrometry

Perchlorate is commonly used as an oxidant in solid fuel propellant for rockets and missiles. Recently perchlorate contamination was found in many aquifers associated with Colorado River and other sites. Perchlorate was also found at elevated level in crops that use contaminated water for irrigation. Ion chromatography with conductivity detection could be used to measure perchlorate levels in drinking and wastewaters as per United States Environmental Protection Agency method 314, but at lower levels and with complexity of the matrix there could be false positive and/or false negative. This study was done to demonstrate the detection of perchlorate with lower detection limit with high ionic matrix by ion chromatography-mass spectrometry.     

Speciation of Pt(II) and Pt(IV) in spiked extracts from road dust using on-line liquid chromatography-inductively coupled plasma mass spectrometry

The emission of platinum from automobile catalytic exhaust converters is well known and the accumulation of Pt in road dust has been studied by the analysis of total Pt contents. However, there are few studies on the speciation of the emitted Pt-compounds in the environment. A separation method with HPLC-UV has been developed by Nachtigall et al. [Chromatogr. A 775 (1997) 197] with aqueous standards of Pt(II)- and Pt(IV)-chloro complexes. Due to the limited selectivity and sensitivity of the UV-detection this method is not suitable for Pt-speciation in road dust extracts. Therefore, in this study the method of Nachtigall et al. was modified to realize an on-line coupling to ICP-MS with the advantage of Pt-specific detection. Calibration was performed with aqueous standards and spiked road dust extracts. Calibration curves were linear with low residual standard deviation (1.3-3.1% for the aqueous standards) and approximately 10-times lower detection limits compared to the HPLC-UV-method. Moreover, the stability of the model species was investigated using isocratic as well as gradient separation. Isotopic ratios of 194Pt, 195Pt, 196Pt and 198Pt were determined for quality control. A new mathematical correction method for the HfO-interference on the 195Pt-signal was developed. Additionally, the elution pattern of further elements in the road dust extracts was monitored and total element contents were determined in unspiked road dust extracts.     

Enhancement of detection sensitivity and cleanup selectivity for tobramycin through pre-column derivatization.

Reversed-phase high-performance liquid chromatography, UV detection and reversed-phase solid-phase extraction (SPE) as analytical methods for pharmaceutical compounds face a challenge when the compound is rather polar and lack UV absorptivity. A good example is tobramycin. To overcome these problems, a method has been developed using pre-column derivatization of tobramycin with o-phthalaldehyde and automated with an autosampler with microrobotic routines. The detection enhancement of the derivatives was achieved by using fluorescence detection which was forty times more sensitive than using UV detection. Recovery studies of standards and spiked serum samples show that pre-SPE derivatization significantly enhances the recoveries (by at least a factor of 3) and the quality of cleanup over post-SPE derivatization.     

The evaluation of solid phase micro-extraction fibre types for the analysis of organic components in unburned propellant powders

This work describes the evaluation of various solid phase micro-extraction (SPME) fibre types for the detection of compounds originating from particles of unburned propellant powders. These compounds may also be found in association with organic gunshot residues (OGSR). Seven SPME fibres were assessed based on their ability to extract the compounds of interest (diphenylamine (DPA), 4-nitrodiphenylamine (4-NDPA), ethyl centralite (EC), nitroglycerin (NG) and dibutyl phthalate (DBP)) from four ammunition types across three calibres (9 mm, 5.56 mm and 7.62 mm). Extracts were analysed by gas chromatography/mass spectrometry (GC/MS). Results indicated that the 65 μm polydimethylsiloxane/divinylbenzene (PDMS/DVB) was the most suitable fibre type for the extraction of these compounds across the ammunition types tested. Optimal extraction time parameters were also assessed with a 35-min period determined to be suitable. A number of previously unreported considerations for extracting propellant powders and potentially OGSR related materials are discussed.     

搅拌萃取–分光光度法检测水环境中阴离子表面活性剂

建立搅拌萃取–分光光度法快速检测水环境中阴离子表面活性剂的含量。用三氯甲烷以800~1 200 r/min搅拌萃取水样与亚甲蓝溶液合成的活性物质,搅拌时间为2 min,静置分层后经脱脂棉过滤,待测。阴离子表面活性剂质量浓度在0.050~0.500 mg/L范围内与吸光度线性良好,相关系数大于0.999 0,方法检出限为0.010 mg/L。选择饮用水源水、农村地下水、湖泊水、城市河道水作为研究对象,平行检测结果的相对标准偏差(RSD)为1.9%~6.5%(n=6),加标回收率为91.3%~110%;对标准物质检测结果的相对误差为–2.3%~3.5%,满足实验室分析质量控制要求和现行地表水、地下水质量标准的评价要求。该方法与国标检测方法相比,在准确度、精密度、灵敏度、分析效率及试剂用量方面均有明显优势,具有推广应用价值。