介绍氦中甲烷气体标准物质的制备方法.以超纯氦气和高纯甲烷为原料,采用称量法制备特性值为10μmol/mol的氦中甲烷气体标准物质.采用气相色谱法(DID检测器)对制备的标准物质进行均匀性、稳定性检验,并对定值结果的不确定度进行评定.研制的气体标准物质均匀性和稳定性良好,有效期为12个月,相对扩展不确定度为2％(k=2).该气体标准物质可用于氦离子化气相色谱仪的方法评价和校准.

介绍异辛烷中六氯苯溶液标准物质研制方法.以色谱纯异辛烷和已准确定值的六氯苯为原料,采用重量–容量法准确制备特性量值为10.0 ng/μL的异辛烷中六氯苯溶液标准物质.分别采用F检验和t检验对标准物质进行均匀性、稳定性检验,并对定值结果的不确定度进行评定.结果表明该标准物质均匀性和稳定性良好,有效期为12个月,定值结果的相对扩展不确定度为3％(k=2),已被批准为国家二级标准物质,编号为GBW(E)082880.该标准物质可用于环境污染物六氯苯的定性及定量分析和气相色谱–质谱联用仪的校准.

研制氢中氦气体标准物质,以高纯氦和高纯氢为原料,采用称量法制备氢中氦气体标准物质.气相色谱(TCD)分析法对制备的标准气体进行性能评价.研制浓度为300μmol·mol-1的氢中氦气体标准物质,相对扩展不确定度为2％(k=2).该气体标准物质具有良好的均匀性和稳定性,可用于氢燃料电池汽车用氢气分析方法的确认和评价.

以色谱纯甲醇和高纯物质萘为原料,采用重量-容量法准确制备特性量值为1.00×10-4 g/mL的甲醇中萘溶液标准物质.研制的标准物质通过了均匀性检验和稳定性考察,并对定值结果进行了不确定度评定.该溶液标准物质已被批准为国家二级标准物质(编号GBW(E)130395),相对扩展不确定度为3％(k=2),可用于液相色谱仪的检定.

建立丙体六六六纯度标准物质的定值及不确定度评定方法,成功研制了丙体六六六纯度标准物质.原料成分采用气相色谱·质谱法(GC-MS)、红外光谱法(IR)和核磁共振法(1H和13 CNMR)进行准确定性.通过均匀性及稳定性考察并检验合格后,采用两种不同原理和精度的方法,即质量平衡法和差示扫描量热法(DSC)进行有机纯度定值.原料中的水分和灰分杂质分别用卡尔费休法、马弗炉灰化燃烧法进行测定.研制的丙体六六六纯度标准物质纯度为99.5％.对定值结果进行不确定度评估,得到扩展相对不确定度为0.4％(k=2).通过比对分析和第三方实验室量值核验,进一步确保定值结果的准确、可靠.该纯度标准物质已被国家质量监督检验检疫总局批准为国家二级有证标准物质[编号GBW(E)061724],可作为测量和量值溯源标准,为相关部门提供服务.

制备了邻苯二甲酸二丁酯-正己烷溶液标准物质,采用气相色谱质谱联用法和红外光谱法对邻苯二甲酸二丁酯原料定性鉴定,并采用气相色谱法和液相色谱法对邻苯二甲酸二丁酯的纯度进行定值,测得邻苯二甲酸二丁酯原料纯度为99.55％.在20℃下,以重量-重量法配制邻苯二甲酸二丁酯溶液标准物质,对溶液进行了均匀性与稳定性检验,并对其量值结果进行了不确定度评定.

Four certified reference materials( CRMs) of mixed metal ions have been developed through preparation,quantitative analysis of certified value,homogeneity,stability and uncertainty evaluation. Its qualification of GBW has been approved. These CRMs has been proved to be useful and convenient in the determination of metals on food contact materials.

In this paper,first,certified reference material (CRM)for the purity determination of dienestrol was prepared by means of semi-preparative high-performance liquid chromatography.Next,a qualitative analysis of the raw materials was performed by using liquid chromatography-mass spectrometry,1H NMR,13C NMR and infrared spectroscopy.Then,the content of organic main ingredients in the prepared CRM was determined via the multi-lab certification with HPLC,and the homogeneity and stability of the CRM were measured.Moreover,the contents of water,ash,volatile materials and inorganic elements were analyzed,with an uncertainty evaluation of the CRMbe-ing finally carried out.The results indicate that (1 )the prepared CRM possesses good homogeneity and is of a sta-ble storage period of 12 months;(2)the contents of water,ash,volatile materials and inorganic elements in the prepared CRM of dienestrol are all less than 0.1%;and (3)the prepared CRM is of a certified purity of 99.4%and a relative expanded uncertainty of 0.6% (k=2).

制备了十氯酮-二氯甲烷溶液标准物质,采用气相色谱-质谱联用法(GC-MS)和红外光谱法(IR)对十氯酮原料定性鉴定,并采用气相色谱法(GC/FID)及多家实验室联合定值法对十氯酮的纯度进行定值,测得十氯酮原料纯度为99.9％.在(20±4)℃下,以重量-容量法配制十氯酮-二氯甲烷溶液标准物质,对溶液进行均匀性与稳定性分析、量值核验,并对其量值结果进行了不确定度评定.

This paper describes the establishment and validation of gas chromatography-flame ionization detector (GC-FID) method for the determination of ethanol amount fraction in bioethanol samples. A general view of the development and optimization of the method is presented. The main aim of this study is the calculation of validation parameters. Selectivity of the method was determined. Linearity (R 2 > 0.999) was obtained in the range from 9.0 to 3040 μg of ethanol per sample (because the mass of the test sample used was around 200 mg, this corresponds to 45–2200 μg g−1). The method showed good recoveries (average 99.0 %), and the relative standard deviation for repeatability and intermediate precision was 4.5 and 5.5 %, respectively. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 10 and 30 μg g−1, respectively. The uncertainty budget was finally done according to the “Guide to the Expression of Uncertainty in Measurement” (GUM), and the relative expanded uncertainty was 4.8 % at coverage of k = 2.

A high performance liquid chromatography tandem mass spectrometric method was established for the determination of glucose concentration in serum with the aid of D-glucose internal standard.D-glucose was added to the serum sample in balance at room temperature.Then the protein was precipitated and extracted in anhydrous ethanol with centrifugation at low temperature.The supernatant was filtered through a 0.22 μm syringe filter into HPLC vials.Identification was achieved by electro-spray ionization(ESI) in positive mode using SIM mode.The calibration curve of glucose showed good linearity with correlation coefficient of R2=0.999 5,recoveries of spiked samples were in the range 100.1% to 102.8%,the detection limit of the method was 8 μg/kg(S/N=3),and the relative standard derivations were 0.49%.The established method is simple,accurate and precise,is appropriate for the determination of serum glucose with great accuracy.