电感耦合等离子发射光谱法与原子吸收光谱法测定铜矿石中铜的不确定度评定

采用电感耦合等离子体发射光谱法(ICP-OES)和原子吸收光谱法(AAS)对测定铜矿石中铜元素进行系统的不确定度评定。建立两种方法测定铜矿石中铜元素的数学模型,分析不确定度的来源主要包括样品称量过程使用的天平、标准工作溶液配置过程所使用的量器、标准工作曲线拟合、测量重复性及试液定容体积等引入的不确定度分量,对引入的各不确定度分量进行量化,计算出各分量的不确定度,通过合成得到测量结果的合成不确定度、扩展不确定度及测试结果的报告形式。比较ICP-OES法和AAS法分别测定3个铜矿石样品中铜的不确定度,随着试样中铜元素浓度的增加,样品不确定度伴随增大趋势,两种方法所测定铜元素结果符合分析结果的相对偏差小于允许限为合格的要求。     

高效液相色谱法测定葡萄酒中合成色素不确定度分析

本文采用高效液相色谱法测定葡萄酒中合成色素含量,通过对测试方法流程进行分析,确定不确定度来源,建立结果数学模型,并计算测定过程中不确定分量、合成不确定度及扩展不确定度。通过分析发现,样品分析过程中回收率产生的不确定度对测量不确定度影响最大,标准溶液配制和稀释过程影响为其次,样品质量称量分量影响最小。     

石墨炉原子吸收光谱法测定乳珍胶囊中铅含量的不确定度分析

探讨石墨炉原子吸收光谱法测定乳珍胶囊样品中铅的测量不确定度评定的方法。用原子分光光度计测定乳珍胶囊样品中的铅含量,根据数学模型从样品称量、样品定容、标准储备液配制、标准曲线线性回归方程和重复测量5个方面进行测量不确定度的计算。对于铅的含量为1．25mg,kg乳珍胶囊样品,其测量不确定度为0．052mg／kg。     

原子吸收光谱法测定铝合金中锌含量测量结果的不确定度评定

通过对原子吸收光谱法测定铝合金中锌的不确定度的系统分析,阐述了测量结果不确定度主要来源于测量试液中锌的浓度、试液定容体积及样品质量产生的不确定度,并对这些分量进行了量化计算,最后计算出合成标准不确定度和扩展不确定度.同时通过评估,得出影响锌含量测定不确定度的主要因素是测量试液中锌浓度引起的不确定度.     

超声波萃取-气相色谱法测定鱼肉中硝基苯类化合物的不确定度评定

对超声波萃取-气相色谱法测定鱼肉中硝基苯类化合物的过程中可能引入的不确定度进行了分析和评定.结果表明不确定度主要来源为标准系列制备过程和样品制作过程引入的不确定度.     

原子吸收光谱法测定TG6钛合金中痕量铁不确定度的分析

通过对原子吸收光谱法测定TG6钛合金中痕量铁的不确定度的系统分析,阐述了测量结果不确定度主要来源于测量试液中铁的浓度、试液定容体积及样品质量产生的不确定度,并对这些分量进行了量化计算,最后计算出合成标准不确定度和扩展不确定度。同时通过评估,得出影响铁含量测定不确定度的主要因素是测量试液中铁浓度引起的不确定度。     

电感耦合等离子光谱法测定婴幼儿营养米粉中铁含量的不确定度评定

以婴幼儿营养米粉为例,根据食品安全国家标准GB5009.268-2016《食品中多元素的测定》中电感耦合等离子体光谱法(ICP-OES)测定营养米粉中的铁含量,分析测试过程中引起不确定度的因素,对涉及到的标准物质,设备仪器,玻璃器皿不确定度的来源进行详细分析和计算。通过实验研究发现,对实验结果影响最大的是标准物质溶液的配制,其引起的相对标准不确定度为0.0542;其次是标准曲线最小二乘法拟合计算浓度,其引起的相对标准不确定度为0.0215。样品称量、样品溶液定容、加标回收、样品重复测定对实验结果影响较小。该研究中ICP-OES法测定婴幼儿米粉铁含量不确定度报告为(58.3±6.9)mg/kg(k=2)。     

电感耦合等离子体发射光谱法测定钢中铈含量的不确定度评定

通过对电感耦合等离子体发射光谱法(ICP-AES)测定钢中铈含量的不确定度的系统分析,阐述了测量结果不确定度主要来源于测量重复性、样品质量、试液定容体积及测量试液中铈的浓度产生的不确定度,并对这些分量进行了量化计算,最后计算出合成标准不确定度和扩展不确定度,得出钢中铈的含量及置信区间为(0.020±0.002)%。同时通过评估,得出影响铈含量测定不确定度的主要因素是测量重复性和测量试液中铈浓度引起的不确定度。     

高效液相色谱法测定苏打水中安赛蜜含量的不确定度评价

用高效液相色谱法测定苏打水中安赛蜜的含量,从样品质量、样品溶液体积和样品溶液浓度3个方面分别分析了影响测量结果不确定度的来源,主要有样品称量、样品溶液定容、标准溶液配制、标准校准曲线拟合、样品重复测量以及回收率校正因子,并分别对其进行量化和合成,最终计算出安赛蜜测量结果的相对标准不确定度为2.00%。发现影响检测结果不确定度的主要因素是标准物质、玻璃量具、标准校准曲线拟合、重复测量和回收率校正因子。     

原子吸收光谱法测定ZL205A铝合金中铜含量测量结果的不确定度评定

通过对原子吸收光谱法测定ZL205A铝合金中铜含量的不确定度的系统分析，阐述了测量结果不确定度主要来源于测量试液中铜的浓度、试液定容体积及样品质量产生的不确定度，并对这些分量进行了量化计算，最后计算出合成标准不确定度和扩展不确定度。同时通过评估，得出影响铜含量测定不确定度的主要因素是测量试液中铜浓度引起的不确定度。     

Experimental mathematical model as a generalization of sensitivity analysis of high temperature spectral emissivity measurement method

The development of an experimental mathematical model describing temperature state of the sample during high temperature spectral emissivity measurement is introduced. Dimensional analysis of the measurement process gives the physical dimensionless quantities and sensitivity analysis of the measurement process provides the large set of performed model experiments. Evaluated experimental mathematical models are presented including their accordance with model experiments. Established equations are generalization of sensitivity analysis of high temperature spectral emissivity measurement method and can be used for computation of spectral emissivity total uncertainty.     

On the many advantages of local-electrode atom probes

Local extraction electrodes offer several crucial advantages for operation of atom probes. Because of the proximity of the local extraction electrode to the specimen, the electric field produced at the specimen apex by a given voltage is enhanced and the voltage required for field evaporation is reduced. In a voltage-pulsed atom probe, the absolute magnitude of the energy uncertainty is correspondingly reduced. High mass resolution (m/deltam > 1000) may therefore be obtained by accelerating the evaporated ions to a greater total potential after the local extraction electrode. The low extraction voltage may also be pulsed rapidly (100 ps rise time) and at high repetition rates (up to 10(5) pulses per second) using currently available solid-state pulsers. Furthermore, a local electrode and intermediate electrodes may be used as optical elements to control the image magnification. All of these benefits may be applied to any type of atom probe. Local-electrode atom probes (LEAP) should be especially advantageous for developing three-dimensional atom probes with high mass resolution and a large field of view. A sample has been developed that consists of many microtips formed on a planar sample using ion beam mask etching. Microtip samples are especially suited to LEAP. Analysis of electrically insulating samples may also be possible with microtip samples in a LEAP. This combination of features suggests flexible, high speed, high mass resolution atom probes that can work with either conventional needle-shaped specimens or the new style of planar microtip specimens.     

三坐标机测量齿轮齿廓的不确定度评价

介绍了坐标测量中几种常用的不确定度评价方法.指出传统的三坐标测量机的测量不确定度评价方法大都不适用于评价坐标测量中面向对象的测量不确定度,并对使用蒙特卡洛方法评价测量不确定度进行了研究.首先,根据三坐标测量机详细标定文件及补偿策略说明建立测量模型.然后,将测量中的采样点通过测量模型生成大量测量结果,并以此评价测量不确定度.在齿廓评价实验中,评定齿廓误差的测量不确定度为0.96 μm时,多次评价结果之间的最大差值不超过0.03 μm,具有可靠的理论依据和较稳定的评定结果.文章指出,目前商用三坐标测量机大都不能为特定的测量对象提供测量不确定度报告,使用蒙特卡洛方法有希望改变此现状.     

Fuzzy Evaluation of Process Capability for Bigger-the-Best Type Products

Many industrial products can be characterised as of the bigger-the-best type. Quality characteristics and process yields of a bigger-the-best type product can be evaluated by using a process capability index. The process capability index Cpl is used to evaluate quality characteristics and process yields of the bigger-the-best type products because the formulae for this index are easy to understand and straightforward to apply. However, since sample data must be collected in order to calculate this index, a great degree of uncertainty may be introduced into the capability assessments due to sampling errors. The other shortcoming of the evaluation is that there exists a fuzzy condition for making a decision for rejecting a null hypothesis. In this paper, a method to incorporate the fuzzy inference with the process capability index in the bigger-the-best type quality characteristics assessments is presented, and a concise score concept is used to represent the grade of the process capability. An example shows that the proposed method is effective in application and thus confirms its feasibility.     

高效液相色谱法测定胡椒中胡椒碱的不确定度评定

进行高效液相色谱法测定胡椒中胡椒碱的不确定度评定,详细介绍进行不确定度评定的方法和步骤,得出胡椒中胡椒碱含量的相对不确定度为0.41%,扩展不确定度为0.8%。根据不确定度评定结果可以得出标准品溶液对不确定度的贡献最大,其次是测量重复性误差,样品称量引起的不确定度最小。该评定方法在实际工作中可用于高效液色谱法检测类型不确定度评定的参考。     

动物源食品中β受体阻断剂残留量测定的不确定度评定

建立了液相色谱-串联质谱(LC-MS/MS)法测定动物源食品中β受体阻断剂残留量的数学模型,依据影响测量结果的不确定度来源,如标准溶液配制、样品称量、回归方程、方法重复性等,对各个不确定度分量进行评定和分析,给出了0.5μg/kg检测水平下,液相色谱-串联质谱法测定食品中β受体阻断剂残留量的相对合成标准不确定度以及扩展不确定度。通过比较各分量不确定度,发现实验过程中最小二乘法拟合带来的不确定度影响最大。     

IMS台站惰性气体传递样品的四极杆质谱分析

The international monitoring system (IMS) station transport noble gas sample is analyzed by quadrupole mass spectrometer. The sample is composed by absolute majority of xenon and nitrogen, therefore, it can be calculated by the method of equation of state of ideal gas (PTV). The relatively expanded uncertainty of the xenon quantity is 4.5% in 95% confidence level.     

SCS-100TU型电子汽车衡秤体结构优化

针对目前汽车衡秤体结构材料利用率低、质量大的问题,将结构优化设计的方法引入到秤体结构设计中。以U型梁和秤台的几何尺寸为设计变量,秤体的最大挠度为约束条件,秤体整体质量为目标函数,利用参数化APDL语言建立了秤体结构的有限元优化模型,对秤体结构进行了优化分析,从而确定了U型梁和秤台的几何尺寸。研究结果表明,在满足秤体刚度和强度设计要求的前提下,秤体结构优化后的质量比原来的降低了6.7%,实现了降低秤体结构质量的目的,提高了材料利用率。     

全蒸发-热电离质谱法的原理、技术和应用

全蒸发-热电离质谱法（total evaporation thermal ionization mass spectrometry, TE-TIMS）无需标准物质进行校正，即可获得高准确度同位素丰度比值测量结果，同时具有样品用量少、重复性高等优点，在核工业、环境、地质、计量学等领域逐渐获得了认可与应用。本文从全蒸发-热电离质谱法的原理、技术特点、研究进展和重要应用等方面对其进行了系统地评述，分析该方法在使用中的关键技术点，并对未来发展进行了展望。     

ID-TIMS 准确测定国际关键比对大米粉中痕量镉

The method of isotope dilution thermal ionization mass spectrometry able to trace to SI was developed to accurately measure trace amount of cadmium in the rice powder sample from CCQM-K24 international key comparison organized by CCQM(Comité Consultatif pour la Quantité de Matière, Paris). By comparison with our previous work, there was much improvement in aspects of digestion of the rice powder sample, separation of cadmium from the sample and dry-mass correction. As a result, the blank of this procedure was reduced and the measurement precisions of isotopic ratios of cadmium were increased. In addition, the uncertainty evaluation of the entire process of measurement was profoundly studied. The analytical result of this work (14.53±0.15) nmol/g was in agreement with the certified value.