湘江底泥多成分标准样品研制

采集湘江流域重金属污染典型地区底泥作原料,经样品预处理、风化干燥、碾磨、过筛和混匀等流程,制备出湘江底泥多成分标准样品（BW8002）,分装于30mL医用塑料瓶中。采用等离子体发射光谱法和原子吸收分光光度法对标准样品中铁、锌、锰、铜、铅和镉含量进行联合定值,均匀性检验及短期稳定性检验均采用等离子体发射光谱法。针对影响测量不确定度的可能因素进行了分析,全面评定了标准样品的不确定度。     

水体污染检测用锡质量控制标准物质研究

研制国家级水质锡质量控制用标准物质,作为锡分析检测的质量控制标准。依据国家标准样品工作导则要求,制备锡标准物质;采用原子荧光光谱法对样品进行均匀性和稳定性研究;以多个实验室协作分析定值的统计结果确定标准值,并进行不确定度评估。经检测锡标准物质均匀性良好,稳定性可达24个月以上;样品量值准确,与美国同种标准物质进行比对具有可比性。研制的锡标准物质符合国家标准物质的技术要求,可用于水质锡元素检测的质量控制、分析方法研究以及分析实验室能力验证等方面。     

水中氨氮成分分析标准物质的研制

采用氯化铵纯度标准物质和三次纯化水为原料,制备了水中氨氮成分分析标准物质。对氯化铵的称量质量进行了校正,运用离子色谱法测定了三次纯化水中氨氮的空白含量,并对研制的标准物质进行了均匀性和稳定性检验。结果表明,研制的水中氨氮成分分析标准物质具备很好的均匀性和稳定性,标准值为100mg/L(Urel=1%,k=2),不确定度较小。     

3-硝基-1,2,4-三唑-5-酮标准物质的制备

介绍了3-硝基-1,2,4-三唑-5-酮(NTO)标准物质的制备方法。以工业品NTO为基体,经热过滤除去机械杂质、重结晶、低沸点溶剂煮洗、真空干燥等步骤,制备出均匀、稳定的NTO标准物质。使用液相色谱测试主体成分含量,对制备的标准物质进行了均匀性初检,并进行均匀性、稳定性评价研究。研究结果表明,NTO标准物质纯度达到99.91%,均匀性良好,稳定性在一年以上,达到了标准物质的技术指标要求。     

大黄蒽醌类标准物质的制备与鉴定

论述了大黄酚、芦荟大黄素、大黄素甲醚、大黄素和大黄酸5种大黄蒽醌(AQs)标准物质的研究工作,详细介绍了标准物质的制备过程、鉴定方法、均匀性检验、稳定性考察以及定值测量方法.制备采用pH梯度萃取法、硅胶柱色谱法和重结晶法,鉴定采用现代波谱分析和高效薄层色谱法.定值采用高效液相色谱法,5种蒽醌的纯度均大于99.0%.采用LC-UV法对4种标准物质的均匀性和稳定性进行了考察,结果表明分装样品间无显著性差异,并且在考察的12个月内稳定.     

2,3,4-三氯苯甲醚标准物质研制与定值

研制了2,3,4-三氯苯甲醚标准物质,介绍了其制备与定值方法。将制备的2,3,4-三氯苯甲醚标准物质分装成500瓶样品,随机抽取其中11瓶做均匀性检验,经F检验和t检验,结果表明在95%置信范围内样品均匀性良好。按短期与长期稳定性分别进行稳定性检验,结果表明在常温20℃下,2,3,4-三氯苯甲醚的稳定期不少于12月。采用液相色谱法和差示扫描量热法2种不同原理的方法对2,3,4-三氯苯甲醚标准物质纯度定值及不确定度评定,并采用液相色谱标准添加的方法确认了2,3,4-三氯苯甲醚标准物质中的主要杂质2,3,6-三氯苯甲醚。定值结果为99.56%± 0.40%（k=2）。     

纯度标准物质RDX的研制

以工业特级品RDX为原料,经热过滤除去机械杂质、重结晶、低沸点溶剂煮洗、真空干燥等步骤,制备出均匀、稳定的RDX纯度标准物质。使用高效液相色谱测试了主体成分含量、水分、无机杂质量等,并采用方差分析法对制备的标准物质进行了均匀性、稳定性评价研究。研究结果表明,RDX纯度标准物质纯度达到99.78%,均匀性和稳定性良好,已达到军用纯度标准物质的技术指标要求。     

水中氯根成分分析标准物质的研制

采用氯化钠纯度标准物质和三次纯化水,制备了水中氯根成分分析标准物质。对氯化钠的称量质量进行了校正,应用离子色谱法测定了三次纯化水中氯根的空白含量,并应用离子色谱法对研制的标准物质进行了均匀性和稳定性检验。结果表明,研制的水中氯根成分分析标准物质具备很好的均匀性和稳定性,标准值为100μg/m L(Urel=1%,k=2),可用于测量仪器校准、测量过程质量控制及分析方法确认和评价。     

采用比较法研制二级气体标准物质

以氮中二氧化碳二级气体标准物质的研制为例,探讨采用比较法研制二级气体标准物质及其不确定度的分析计算,其中标准物质的制备采用称量法配制,并对所研制的样品进行了均匀性、稳定性试验,结果表明,所研制的氮中二氧化碳气体的标准物质在一年的考察期内,其均匀性、稳定性、量值不确定度均达到国家二级标准物质要求,符合申报条件。     

水中硒成分分析标准物质研制

以高纯硒、高纯盐酸和三次纯化水为原料,在对高纯硒的纯度进行定值的基础上,采用重量—容量法制备了水中硒成分分析标准物质。分别采用F检验和直线拟合法对研制的标准物质进行均匀性检验和稳定性考察。结果表明,研制的水中硒成分分析标准物质具有很好的均匀性和短期、长期稳定性,标准值为1 000μg/m L,相对扩展不确定度U_(rel)=1%(k=2),采用电感耦合等离子体发射光谱法与国内同类标准物质比对,表明该标准物质量值准确且具有溯源性。     

罐装婴幼儿奶粉营养标签及营养素的调查分析

目的分析罐装信息,为消费者选购国内外婴幼儿奶粉提供细致参考。方法通过网络调查和实体店走访的形式,调查分析不同品牌、不同年龄阶段罐装奶粉的营养标签等信息。结果京东麦乐购母婴商城和实体店31种品牌罐装奶粉的营养标签标识率均为100%,其中标识率较高的营养成分包括能量、蛋白质、碳水化合物、脂肪、维生素(A,D,E,K,C)和矿物质(钙、铁、磷、锌)。美系罐装奶粉蛋白质含量标识数高于其他系别,但其他营养素标识数则没有显著差异。同一罐装奶粉品牌不同系列的营养标识中重要营养素含量大同小异,而不同品牌的罐装奶粉营养素含量标识数则差异较大。其中,美赞臣罐装奶粉注重提高婴幼儿脑部智力发育,其DHA和ARA含量标识数较高(P0.05);雅培罐装奶粉注重增强婴幼儿体质,其钙、铁、磷等矿物质含量的标识数较高(P0.05);惠氏罐装奶粉的叶黄素含量的标识数较高(P0.05),且含有天然胡萝卜素的标识。结论消费者按照婴幼儿的体质、生长阶段和生活喜好的不同,可根据营养标签来选择最合适的罐装奶粉。     

Certification of Three Reference Materials for α- and γ-Tocopherol in Edible Oils

Tocopherols are important vegetable oil constituents, and their reliable quantitative analysis depends largely on the existence and quality of certified reference materials (CRMs) which provides traceability of the measurement results to the SI units. Since there is a lack of suitable CRMs in case of tocopherols analysis, three matrix reference materials from corn, peanut and soybean oils were certified for the content of α and γ-tocopherols. Homogeneity and stability of the prepared reference materials were studied and certification was done by two independent chromatographic analytical methods. The measurement results were statistically treated and the certified values of α and γ-tocopherol in corn, peanut and soybean oils were assigned and their associated expanded uncertainties were estimated as: 322.04 ± 8.62, 771.48 ± 15.31, 106.23 ± 5.19, 108.94 ± 9.72, 140.66 ± 5.93, 418.00 ± 14.36 mg/kg, respectively. These values were found useful for many food testing laboratories in validation of analytical methods and analytical quality control.     

Certification of vitamins and carotenoids in SRM 3280 multivitamin/multielement tablets

A new multivitamin/multielement dietary supplement Standard Reference Material (SRM) has been issued by the National Institute of Standards and Technology (NIST), with certified and reference concentration values for 13 vitamins, 24 elements, and 2 carotenoids. The constituents have been measured by multiple analytical methods with data contributed by NIST and by collaborating laboratories. This effort included the first use of isotope dilution mass spectrometry for value assignment of both fat-soluble vitamins (FSVs) and water-soluble vitamins (WSVs). Excellent agreement was obtained among the methods, with relative expanded uncertainties for the certified concentration values typically ranging from <2% to 15% for vitamins.     

Estimation of Uncertainty in the Determination of Serum Electrolytes (Na,K, Ca,Mg) by Flame Atomic Absorption Spectroscopy

From a standardized and validated method to quantify serum electrolytes (Na, K, Ca and Mg) by flame atomic absorption spectroscopy, combined relative uncertainty (CRSU) and the percentage of combined relative standard uncertainty (% CRSU) were determined. For this, analytical grade standards were used and later from a certified reference material (NIST2670a). Previously, the sources of uncertainty used in the measurement using the Ishikawa diagram (cause-effect) were established, including mass concentration, calibration curves, volume, reactive targets, certified reference material, dilution and repeatability. Quantification of the metals was performed using the atomic absorption spectroscopy technique employing a Perkin Elmer model 3100 equipment. The values obtained for the CRSU on average are below 0.030 and for the % CRSU on average they are below 3.1%. These results indicate that the uncertainty values are acceptable since they are below the recommended values for these metals.     

X射线荧光光谱法测定不锈钢注射成型零部件中化学成分

提出了用X射线荧光光谱法测定不锈钢注射成型零部件中化学成分的方法。采用一套不锈钢标准样品建立校准曲线,对谱线的重叠干扰和基体效应进行校正。在优化的条件下,对YSBS20111-99-6不锈钢标准样品中Si、Mn、Cr、Ni、Cu、Mo、Co、V等元素进行了12次测定,各元素的测定值与该标样的标准值相一致,测定结果的相对标准偏差均小于1％。用本方法对不锈钢注射成型零部件样品进行了测定,其分析结果与用ICP-AES法的测定值相一致。本方法快速、简便、准确和可靠,可用于不锈钢注射成型或其他类似零部件中化学成分的分析。     

食品营养标签分析的标准物质研究

提高测量精确性可以保证食品营养标签提供食品营养可靠可知性和产品质量,是提高食品营养质量评价的重要手段。食品营养成分标准物质可保证测量有效性,是验证营养标签分析方法和实验室内分析的质量保证所必需的,对营养标签标准和标签法具有支持和推动作用。阐述了我国和美国食品营养分析标准物质,并介绍了美国AOAC作为发展一系列基于蛋白质、脂肪和碳水化合物的代表所有食品标签分析的标准物质的食品三角形模式图。     

Development of Four Parabens Reference Materials Certified for Purity Mass Fraction by Mass Balance Approach

The need for pure organic reference materials for establishing traceability to the international system of units, validation of analytical methods and assuring quality of the measurement results has been increased recently. Mass balance approach was used for development of four reference materials from methyl, ethyl, propyl and butylparaben certified for purity mass fraction. The analyte mass fraction in each reference material was assigned by measurements of detectable impurity components include determination of organic, inorganic, water and volatile impurities by HPLC–DAD and GC–FID, IC, Karl Fisher and headspace, respectively. Assignment of certified purity was based on results from independent liquid and gas chromatographic methods. The certified purity values of methyl, ethyl, propyl, and butylparaben and their corresponding expanded uncertainties (k = 2.0) were found (998.48 ± 0.71), (997.80 ± 1.36), (998.20 ± 0.51) and (998.35 ± 0.89) mg/g, respectively. The prepared reference materials can be used as a measurement standard for analytical instruments and as a control sample for assuring quality of cosmetics, pharmaceutical and food products.     

“Standard Samples in the Quality System for Measurements in Analytical Chemistry”

Problems of providing measurement quality in analytical chemistry using reference materials certified by primary methods are considered in this paper. We describe a scheme of establishing the traceability of measurement results in a chemical composition of substances to SI units, exemplifying it by reference materials, certified in FGUP “UNIIM” by a primary method—coulometric titration technique. 1 In the original article, there were many translation errors. Here the article is reproduced in full with corrections. The online version of the original article can be found at     

Development of a digital micromirror spectrometer for analytical atomic spectrometry

A digital micromirror device (DMD) has been incorporated into a novel spectrometer for use in analytical atomic spectrometry. The device can be taken from a commercial computer projector. A protective glass window covering the DMD chip limits the viewable wavelengths to the visible range. The DMD is used to project an image of the light source onto the exit plane of a flat-field spectrograph. A single photomultiplier tube is used for detection. The high switching rate of the micromirrors (15 μs) enables rapid full-spectrum capture, wavelength-modulation, source-modulation, fast narrow-wavelength window scans, and rapid-wavelength "jumping." Calcium, sodium, and potassium have been determined in several standard reference materials (tomato leaves, bovine liver, rice flour, total diet) by flame atomic absorption and emission spectrometry. Absorption sensitivities for each element are near the 0.02 μg/mL level, and detection limits for both absorption and emission are near the 0.01 μg/mL level. Elemental recoveries were within 10% of certified values for most reference materials.     

转基因水稻TT51-1标准物质的研制

将筛选后的转基因水稻TT51-1和非转基因水稻明恢63种子分别冷冻研磨成粉末,采用重量法配置了5个不同水平的标准物质。经检验该标准物质的均匀性良好,可在4℃保存条件下存储1年。标准物质采用重量法的质量分数作为标准值,数字PCR测定拷贝数分数作为参考值,通过转基因水稻与非转基因水稻种子粉末提取效率比值校准的数字PCR定值结果与重量法质量分数定值结果之间具有等效一致性,该标准物质可用于转基因水稻TT51-1的定量PCR检测及其特异性检测方法的评价。