the uv-spectrophotometric method of analysis was proposed for simultaneous determination of fluoxetine (flx) and sertraline (srt). considering the strong spectral overlap between uv-vis spectra of these compounds, a previous separation should be carried out in order to determine them by conventional spectrophotometric techniques. here, full-spectrum multivariate calibrations adaptive neuro-fuzz...

Two robust approaches to principal component analysis and factor analysis are presented. The different methods are compared, and properties are discussed. As an application we use a large geochemical data set which was analyzed in detail by univariate (geo-)statistical methods. We explain the advantages of applying robust multivariate methods.

in recent years, alternative methods have been used for estimation of soil salinity. therefore, at present research, 600 soil samples collected from ardakan in central iran. then em38 and terrain parameters such as wetness index, land index and curvature as readily measured properties and soil salinity (0-30 and 0-100) as predicted variables were measured. after that, the data set was divided i...

This chapter presents an introduction to robust statistics with applications of a chemometric nature. Following a description of the basic ideas and concepts behind robust statistics, including how robust estimators can be conceived, the chapter builds up to the construction (and use) of robust alternatives for some methods for multivariate analysis frequently used in chemometrics, such as prin...

A 1H NMR method for the quantification of dermatan sulfate impurities in heparin industrial samples is proposed. The method is based on the analysis of 1H NMR spectral data by multivariate calibration. The 1H NMR spectra of heparin and dermatan sulfate standards showed characteristic profiles. Thus, differences in the methyl peaks of acetamido groups of heparin and dermatan sulfate were greatly...

The predictability of multivariate calibration models, calculated with offline near-infrared spectroscopy (NIRS), assessing impact of magnesium stearate (MgSt) fraction, blending time, and compression force on the tablet breaking force (TBF) of SPRESS® B820 was statistically compared. Tablets of lubricated SPRESS® B820 were prepared by varying lubrication and compression conditions using 24 ful...

Surveys, by their very nature, result in data structures that are multivariate. While recognizing the value of simple approaches to survey data analysis, the present chapter illustrates the benefits of a more in-depth analysis, for selected population subgroups through the application of multivariate techniques. Software packages are now available that make possible the application of these mor...

Simultaneous spectrophotometric analysis of a multi-component dosage form of olmesartan, amlodipine and hydrochlorothiazide used for the treatment of hypertension has been carried out using various chemometric methods. Multivariate calibration methods include classical least squares (CLS) executed by net analyte processing (NAP-CLS), orthogonal signal correction (OSC-CLS) and direct orthogonal ...