共查询到20条相似文献,搜索用时 8 毫秒
1.
俞汝勤 《高等学校化学学报》1990,11(12):1357-1361
本文综合讨论了化学计量学的一些基础问题,包括分析信息理论、实验设计与优化、采样理论、分析检测理论、校正理论、分析信号处理、化学模式识别和计算机数字模拟等,并介绍了作者实验室的部分近期工作。 相似文献
2.
MATLAB在化学计量学中的应用 总被引:9,自引:0,他引:9
化学计量学是数学和统计学,化学及计算机科学相互交叉形成的一门新的化学分支学科,是解决化学问题的强有力工具,目前运用于化学计量学的商品软件有MATLAB、Maple,MathCAD,EXCEL,SPSS等。MATLAB是一种高性能的数值计算的科学计算语言,具有程序开发环境简洁直观,数值稳定性好,函数资源丰富的特点,本文以几种常用的化学计量学方法为例,讨论了MATLAB在化学中的应用。 相似文献
3.
化学计量学在电分析化学中的应用 总被引:8,自引:2,他引:8
本文对化学计量学各种方法,诸如多元校正,因子分析,信号处理,参数估计,模式识别等电分析化学中的应用作了回顾及评述,指出了化学计量学电分析化学中应用的良好前景。 相似文献
4.
5.
6.
7.
8.
化学计量学中的稳健估计方法 总被引:13,自引:5,他引:13
稳健统计学是八十年未才基本定型的统计学分支,它是针对实际情况中假设模型常常只是对实际数据的一种近似而导致传统统计学推断失误而发展起来的。稳健统计学构造一些新的具有稳健性的方法,使得在假设模型满足时,稳健方法具有接近最优的性能;在实际数据与假设模型有差别时,其性能仍为次优的;而在实际数据与假设模型差别大时,统计方法的性能也不会变得过差。本文介绍了稳健估计的一般概念。综述了化学计量学中的稳健估计方法, 相似文献
9.
评述了化学计量学方法在生产过程分析中各个方面 ,如过程优化、过程模拟、仪器及仪器校正、过程监测等方面的应用 ,并展望了化学计量学在过程分析中的应用前景 相似文献
10.
《Analytical letters》2012,45(2):291-300
The authenticity of Chinese liquor concerns consumer health and economic issues. The traditional characterization methods are time-consuming and require experienced analysts. The use of near-infrared (NIR) spectroscopy and chemometrics to classify Chinese liquor samples was investigated using 128 liquors. The spectral region between 5340 cm?1 and 7400 cm?1 was found to be most informative. Principal component analysis was employed to characterize liquor and principal components were extracted as inputs of training classifiers. Several supervised pattern recognition methods including K-nearest neighbor, perceptron, and multiclass support vector machine were used as algorithms of constructing classifiers. The initial principal components and all spectral variables were used as the input of training models. In terms of the misclassification ratio, the support vector machine approach was the most accurate. The results indicated that near-infrared spectroscopy and chemometrics are an alternative to conventional methods for the characterization of liquor. 相似文献
11.
12.
13.
《Electroanalysis》2005,17(13):1215-1221
The coupling of a capillary electrophoresis (CE) microchip with electrochemical detection with a chemometric approach was used for the classification of wines. Cabernet Sauvignon wine samples from 3 different geographical regions were used for verifying the discriminating power of the microchip electrophoretic technique using high separation voltage (3000 V) with analysis time of only 60 seconds. Electrophoretic data were transformed into initial 14 variables, concerning peak's area and peak's height. Principal component analysis was applied to optimize the information given by the electrophoretic data sets. Results of classification using LDA and CART were promising and the preliminary model was able to classify samples on the basis of their geographical origin. While the coupling of microchips with chemometrics approaches is illustrated for a former tentative of the classification of wines it could be readily extended to a wide range of other important applications. 相似文献
14.
化学计量学在有机物电分析化学中的应用 总被引:1,自引:0,他引:1
化学计量学在有机物电分析化学中的应用日益广泛,并发挥重要的作用。本文就化学计量学方法在色素、抗氧化剂、维生素、氨基酸、环境污染物、农药及药物等电分析化学方面的应用作一综述。引用参考文献58篇。 相似文献
15.
In this paper, two spectral data sets have been used to illustrate the importance of maintaining chemical information whilst generating predictive multivariate calibration models. The first data set is based on 26 duplicate UV/VIS spectra for four meal ions (Fe, Ni, Co, Cu) present at varying concentrations in aqueous solution. Spectra were collected across the range 180–800 nm at a resolution of 3.5 nm generating 211 data points for each sample. Calibration was carried out using multiple linear regression (MLR) and a K-matrix approach to demonstrate the advantages the latter method has in describing real spectral features. In addition, the limitation of MLR in accommodating noise and spectral overlap in the data is also illustrated. The second data set based on NIR spectroscopy, was generated using a four-level 2 factor Factorial design strategy and consisted of two additives present at a range of concentrations in an aqueous caustic system, with the spectra being collected over the range 10,000–3000 cm−1. Whilst a conventional partial least squares (PLS) model was applied to the data, it was through the use of variable selection (VS) prior to PLS and the application of weighted ridge regression (WRR) techniques that the need to develop chemometric methodology which intuitively reflected chemical information has been demonstrated. The results will also illustrate how a poorly designed experimental design protocol and missing data can limit the performance of the calibration models generated. The aims of this paper are not to prescribe ideal calibration methodology but rather to demonstrate the relevance of selecting multivariate calibration methodology that relates more to the chem rather than just the metrics in chemometrics. 相似文献
16.
化学计量学在动力学多组分分析中的应用是近年来非常活跃的领域。本文从多元校正、卡尔曼滤波、协同效应校正、人工神经网络及计算机应用等方面对化学计量学速差动力学分析领域出现的新方法及新动向作一评述,并对今后的工作进行了展望。引用文献99篇。 相似文献
17.
在pH=6.82的Britton-Robinson缓冲溶液中,采用循环伏安法和微分脉冲溶出伏安法对醚类除草剂甲羧除草醚(Bifenox)和三氟羧草醚(Acifluofen)的伏安行为进行了研究,发现吸附时间为50 s时此电化学体系达到平衡,而且微分脉冲溶出伏安法能给出较高的灵敏度,甲羧除草醚和三氟羧草醚分别在-685 mV和-700 mV处具有良好还原峰,但由于峰电位接近而谱峰重叠,很难分别测定.本文采用化学计量学方法来解析重叠峰并完成这两种除草剂的定量分析.甲羧除草醚和三氟羧草醚的测定线性范围分别为0.02~0.18 μg·5mL~(-1)和0.02~0.16 μg·5mL~(-1),检出限分别为0.0073 μg·5mL~(-1)和0.0068 μg·5mL~(-1).利用该方法对水样中的甲羧除草醚和三氟羧草醚进行直接测定,获得了较好的定量分析结果. 相似文献
18.
19.
Anna M. Hawrył Mirosław A. Hawrył Ryszard Świeboda Klaudia Stępak Małgorzata Niemiec Monika Waksmundzka-Hajnos 《Analytical letters》2017,50(13):2078-2089
The raw material from Mentha piperita L, M. arvensis L, M. longifolia L, M. spicata, and M. suaveolens from various locations were extracted using steam distillation to obtain the mint essential oils. High-performance liquid chromatography was used to obtain fingerprints of the mint samples. SpecAlign, Savitzky–Golay, recursive alignment by fast Fourier transform, Pearson’s correlation coefficient, and principal component analysis were used to characterize the chromatograms. The results were used to confirm the similarities of M. longifolia collected in Ostrowsko, Poland in 2013 and 2014. The considerable similarity of these M. longifolia samples demonstrates that the reported chemometric approach is suitable for the classification of plant materials. 相似文献
20.
化学计量学方法解析苯胺电解过程 总被引:3,自引:2,他引:1
在对混合物样品的紫外可见光谱测量数据阵矩进行主成分分析、潜变量投影等方法解析后,得到一种物质的光谱曲线和另一种物质的动力学曲线,这在化学计量学意义上是一类比较特殊的黑色体系.提出了一种解析这个难题的算法,并详细论证了方法中不可避免的唯一解问题.对于模拟数据,解析结果证明本算法的正确性.用本法解析了苯胺水溶液电解过程,得到苯胺和中间物的动力学曲线及其纯光谱. 相似文献