连续流动注射法测定水中阴离子表面活性剂的不确定度评定

对流动注射法测定水中阴离子表面活性剂的不确定度进行分析,找出影响不确定度的主要因素,对不确定度进行研究,给出合成标准不确定度和扩展不确定度。     

陶瓷材料及制品化学分析中氧化钾含量的不确定度评定

本文结合实际工作,利用原子吸收分光光度法对陶瓷材料及制品化学分析中的氧化钾含量进行了测定,对测量结果进行不确定度分析与评价。通过不确定度分析,找出不确定度的主要来源,对每一个不确定度分量进行评定和量化,计算出合成不确定度及扩展不确定度。     

日用陶瓷器铅溶出量测量的不确定度评定

本文结合实际工作,利用原子吸收分光光度法对日用陶瓷器铅溶出量进行了检测,对测量结果进行不确定度分析与评价。通过不确定度分析,找出不确定度的主要来源,对每一个不确定度分量进行评定和量化,计算出合成不确定度及扩展不确定度。     

煤焦检验设备热电偶检定不确定度评定

简述热电偶的热电偶检定过程,依据JJG351对K型偶进行检定,并依据JJF1059对检定结果的不确定度进行评定。分析检定过程中不确定度的来源及其种类,对不确定度分量、合成不确定度和扩展不确定度进行了评定。     

食用植物油中酸价测量结果的不确定度评估

应用不确定度评定方法对酸价测量结果进行不确定度分析与评估,得出样品中酸价的合成标准不确定度和扩展不确定度。根据油脂中酸价测定的原理和步骤建立数学模型,对不确定度进行评估。该方法测定油脂中酸价的合成不确定度u（X）=0.03,扩展不确定度U=0.06,滴定终点判断引入的标准不确定度影响较大。     

铜精矿中铜含量测定的不确定度评定

通过滴定法测定铜精矿中铜含量,对其测量不确定度进行评定,详尽地分析了整个实验过程中的不确定度来源,并对各部分不确定度分量进行量化计算,得出合成标准不确定度和扩展不确定度,并以不确定度的形式给出测定结果。     

紫外分光光度法测定陶瓷材料及制品中氧化钛含量的不确定度评价

本文利用紫外分光光度法对陶瓷材料及制品化学分析中的氧化钛含量进行了测定,对测量结果进行不确定度分析与评价。通过不确定度分析,找出不确定度的主要来源,计算出合成不确定度及扩展不确定度。     

元素分析仪测定煤中碳、氢、氮含量的不确定度评定

采用元素分析仪对煤中碳、氢、氮元素含量进行检测,通过建立数学模型分析检测过程中不确定度的来源,对各个不确定度分量进行了系统全面评定和计算,各个不确定度分量计算得到合成不确定度和扩展不确定度。结果表明,影响煤中碳、氢、氮含量测量不确定度的主要来源是样品质量引入的不确定度和标准物质产生的不确定度。     

离子色谱法测定水中溴化物的不确定度研究

对离子色谱法测定水中溴化物的不确定度进行分析,找出影响不确定度的因素,对不确定度进行研究,给出不确定度,如实反映测量的置信度和准确性。     

陶瓷砖断裂模数测量结果的不确定度评定

对陶瓷砖断裂模数测量不确定度的来源进行了分析,并对各不确定度分量进行了分析和量化,求得合成标准不确定度和扩展不确定度分别为10.04%和20.08%。     

衣料用液体洗涤剂中总活性物含量的不确定度评定

对衣料用液体洗涤剂中总活性物的不确定度来源进行了详细的分析和测定过程中的主要不确定度分量进行了合理评定,包括样品质量称量引入的不确定度;称量乙醇溶解物质量引入的不确定度;硝酸银标准溶液的标准浓度引入的不确定度;数字滴定器引入的不确定度以及测量的重复性所引入的不确定度,最后合成标准不确定度乘以95%置信概率下的扩展因子k=2获得测量结果的不确定度。     

Improving uncertainty evaluation of process models by using pedigree analysis. A case study on CO2 capture with monoethanolamine

This article aims to improve uncertainty evaluation of process models by combining a quantitative uncertainty evaluation method (data validation) with a qualitative uncertainty evaluation method (pedigree analysis). The approach is tested on a case study of monoethanolamine based postcombustion CO₂ capture from a coal power plant. Data validation was used to quantitatively assess the uncertainty of the inputs and outputs of the MEA model. Pedigree analysis was used to qualitatively assess the uncertainty in the current knowledge base on MEA carbon capture systems, the uncertainty in the MEA process model, and the uncertainty of the MEA model results. The pedigree review was done by 13 international experts in the field of postcombustion carbon capture with chemical solvents.The data validation showed that our MEA model is accurate in predicting specific reboiler duty, and CO₂ stream purity (4% and 1% difference respectively between model and pilot plant results), but in first instance it was less accurate in predicting liquid over gas ratio, and cooling water requirement (54% and 23% difference respectively between model and pilot plant results). The pedigree analysis complemented these results by showing that there was fairly high uncertainty in the thermodynamic, and chemistry submodels, as reflected in the low pedigree scores on most indicators. Therefore, the model was improved to better resemble pilot plant results.The results indicate that using a pedigree approach improved uncertainty evaluation in three ways. First, by highlighting sources of uncertainty that quantitative uncertainty analysis does not take into account, such as uncertainty in the knowledge base regarding a specific phenomenon. Second, by providing a systematic approach to uncertainty evaluation, thereby increasing the awareness of modeller and model user. And finally, by presenting the outcomes in easy to understand numerical scores and colours, improving the communication of model uncertainty. In combination with quantitative validation efforts, the pedigree approach can provide a strong method to gain deep insight into the strengths and weaknesses of a process model, and to communicate this to policy and decision-makers.     

氢化物原子荧光光谱法测定海产品中砷含量的不确定度评定

目的:建立氢化物原子荧光光谱法测定海产品中砷含量的不确定度评定程序和方法。方法:建立数学模型,应用测量不确定度评定理论,结合实验方法,确定和计算测定过程中各不确定度分量,计算合成不确定度和扩展不确定度。结果:本试验方法用氢化物原子荧光光谱法测定海产品中砷含量的不确定度为:5.3%。结论:测量结果与测量不确定度的同时给出,更能显示出结果的可靠。     

X-射线荧光光谱法测量聚乙烯中汞含量不确定度评定

采用国际通用的方法对X-射线荧光光谱法测定聚乙烯中的汞含量的不确定度进行了评定。建立了该方法的定量数学模型并推导出不确定度计算公式,分析了不确定度的主要来源;评定了不确定度分量及扩展不确定度;汞量的不确定度评定报告为:XHg=(198±5.92)mg/kg(k=2,v=10)。     

ICP-AES法测定铝合金中铅含量不确定度评定

采用国际通用的方法对电感耦合等离子体原子发射光谱法测定铝合金中的铅含量的不确定度进行了评定。建立了该方法的定量数学模型并推导出不确定度计算公式,分析了不确定度的主要来源;评定了不确定度分量及扩展不确定度;铅量的不确定度评定报告为:XPb=(3.77±0.17)mg/g。     

容量法测定生活饮用水总硬度的不确定度评定

根据生活饮用水总硬度测定的方法步骤,对采用EDTA容量法测定总硬度的测量不确定度进行了评定。从锌标准溶液配制、Na2EDTA标准溶液标定、样品溶液测定3个环节归纳了不确定度的来源。通过建立数学模型,给出了测定实验室自来水总硬度的各不确定度分量的详细评定过程,由各不确定度分量求得了总硬度的合成标准不确定度及扩展不确定度,当置信水平95%时,得出实验室自来水总硬度的测量不确定度为246.9±1.02mg·L-1。     

Assessing the sensitivity of modelled estimates of N2O emissions and yield to input uncertainty at a UK cropland experimental site using the DailyDayCent model

Biogeochemical models such as DailyDayCent (DDC) are increasingly used to help quantify the emissions of green-house gasses across different ecosystems and climates. For this use they require parameterisation to represent a heterogeneous region or are site specific and scaled upwards. This requires information on inputs such as climate, soil, land-use and land management. However, each input has an associated uncertainty, which propagates through the model to create an uncertainty in the modelled outputs. To have confidence in model projections, an assessment of how the uncertainty in inputs propagated through the model and its impact on modelled outputs is required. To achieve this, we used a pre-defined uncertainty range of key inputs; temperature, precipitation, clay content, bulk density and soil pH, and performed a sensitivity and uncertainty analysis, using Monte Carlo simulations. This allowed the effect of measurement uncertainty on the modelled annual N₂O emissions and crop yields at the Grange field experimental site to be quantified. Overall the range of model estimates simulated was relatively high and while the model was sensitive to each input parameter, uncertainty was driven by the sensitivity to soil pH. This decreased as the N fertiliser application rate increased, as at lower N application rates the model becomes more sensitive to other drivers of N mineralisation such as soil and climate inputs. Therefore, while our results indicate that DDC can provide a good estimate of annual N₂O emissions and crop yields under UK conditions, reducing the uncertainty in the input parameters will lead to more accurate simulations.     

Distributional uncertainty analysis and robust optimization in spatially heterogeneous multiscale process systems

Multiscale models have been developed to simulate the behavior of spatially‐heterogeneous porous catalytic flow reactors, i.e., multiscale reactors whose concentrations are spatially‐dependent. While such a model provides an adequate representation of the catalytic reactor, model‐plant mismatch can significantly affect the reactor's performance in control and optimization applications. In this work, power series expansion (PSE) is applied to efficiently propagate parametric uncertainty throughout the spatial domain of a heterogeneous multiscale catalytic reactor model. The PSE‐based uncertainty analysis is used to evaluate and compare the effects of uncertainty in kinetic parameters on the chemical species concentrations throughout the length of the reactor. These analyses reveal that uncertainty in the kinetic parameters and in the catalyst pore radius have a substantial effect on the reactor performance. The application of the uncertainty quantification methodology is illustrated through a robust optimization formulation that aims to maximize productivity in the presence of uncertainty in the parameters. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2374–2390, 2016     

马尾松松节油标准样品的定值研究

研究了马尾松松节油标准样品的均匀性、稳定性及其定值方法。马尾松松节油标准样品中4种指标成分的含量测定采用气相色谱面积归一化法。制备得到的马尾松松节油标准样品通过了均匀性检验,且在36个月内是稳定的。马尾松松节油标准样品的多实验室联合定值结果为:α-蒎烯含量的标准值84.63%,标准不确定度0.12%,扩展不确定度(95%置信率)0.24%;β-蒎烯含量的标准值9.56%,标准不确定度0.07%,扩展不确定度(95%置信率)0.14%;苧烯含量的标准值1.66%,标准不确定度0.03%,扩展不确定度(95%置信率)0.06%;长叶烯含量的标准值0.43%,标准不确定度0.04%,扩展不确定度(95%置信率)0.08%。     

Uncertainty in contact angle measurements from the tangent method

The uncertainty in contact angles from sessile drops measured by the tangent method was estimated using a standard error propagation technique involving partial derivatives. If contact angles are <60°, then uncertainty of the tangent method appears to be quite small,≤ ± 2°. However, as θ values approach 90°, uncertainty increases asymptotically and can exceed ±5°.