A Chemometric Approach

The application of Equation 1.126 to the thermodynamic functions of a variety of Lewis acid/base reactions shows [184] that their responses to the electrostatic/covalent character increase in the order —AS —AH —AG. A rather covalent character is found for the spectroscopic scale of hydrogen-bond basicity Ai (OH), and the sequence —AS A v(OH) —AH —AG is observed for the formation of hydrogen bonds. 

PO bases (O), CO (9) and SO bases (m), nitrile (D), ethers (a), pyridines (m) and amine (U). The f parameters of PhN02 (ts) and PhNMe2 (O) are unknown, but the positions of PhN02 near oxygen bases and of PhNMe2 near the amine appear satisfactory. 

The correlation coefficient r = 0.952 can be compared with the value r = 0.767 found in the correlation of diphenylamine basicity with the single 4-fiuorophenol basicity. 

A comparison of the slopes and intercepts of Equations 1.130-1.132 shows thathydrogen-bond complexation increases with the medium in the order CCI3CH3 CCI4 gas. 

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Note These equations are from Doming, S. N. Morgan, S. L. Experimental Design A Chemometric Approach. Elsevier Amsterdam, 1987, and pseudo-three-dimensional plots of the response surfaces can be found in their figures 11.4, 11.5, and 11.14. The response surface for problem (a) also is shown in Color Plate 13. 

Deming, S. N. Morgan, S. L. Experimental Design A Chemometric Approach. Elsevier Amsterdam, 1987. 

S. N. Denting and S. L. Morgan, Experimental Design A Chemometric Approach Elsevier Science Publishing Co., Inc., Amsterdam, The Netherlands, 1987. D. D. Wolff and M. L. Parsons, Pattern Recognition Approach to Data Interpretation Plenum Press, New York, 1983. 

Because of peak overlappings in the first- and second-derivative spectra, conventional spectrophotometry cannot be applied satisfactorily for quantitative analysis, and the interpretation cannot be resolved by the zero-crossing technique. A chemometric approach improves precision and predictability, e.g., by the application of classical least sqnares (CLS), principal component regression (PCR), partial least squares (PLS), and iterative target transformation factor analysis (ITTFA), appropriate interpretations were found from the direct and first- and second-derivative absorption spectra. When five colorant combinations of sixteen mixtures of colorants from commercial food products were evaluated, the results were compared by the application of different chemometric approaches. The ITTFA analysis offered better precision than CLS, PCR, and PLS, and calibrations based on first-derivative data provided some advantages for all four methods. ... 

Betti et al. [85] present a chemometric approach for the analysis of flavonoids and related compounds by planar chromatography. 

Volume 3 Experimental Design A Chemometric Approach, by S.N. Deming and S.L. Morgan... 

Meglen RR (1990J Analytical problem solving, reference materials, and multivariate quality control A chemometrics approach. Fresenius J Anal Chem 338 363-367. 

R. Kaliszan, Structure and Retention in Chromatography. A Chemometric Approach, Harwood Academic Publishers, Amsterdam (1997). 

Deming SN, Morgan SL (1993) Experimental design a chemometric approach, 2nd edn. Elsevier, Amsterdam... 

Experimental Design A Chemometric Approach, by S.N. Deming and S.L. Morgan Advanced Scientific Computing in BASIC with Applications in Chemistry, Biology and Pharmacology, by P. Valko and S. Vajda PCs for Chemists, edited by J. Zupan... 

Experimental design a chemometric approach / Stanley N. Deming and Stephen L. Morgan. — 2nd rev. and expanded ed. 

Churchley, J.H. Greaves, A.J. Hutchings, M.G. Phillips, D.A.S. Taylor, J.A. A chemometric approach to understanding the bioelimination of anionic, water-soluble dyes by a biomass - Part 3 Direct dyes. J. Soc. Dyers Colour. 2000, 116, 279-284. 

Take a chemometric approach ignore the question as to what causes the peak, and select the absorbing wavelength on an empirical basis to give the best correlation with traditional chemical analyses. 

Francois, Y, Varenne, A., Juillerat, E., Servais, A.-C., Chiap, R, and Gareil, R., Nonaqueous capillary electrophoretic behavior of 2-aryl propionic acids in the presence of an achiral ionic liquid A chemometric approach, /. Chromatogr. A,... 

S. N. Deming and S. L. Morgan, Experimental Designs a Chemometric Approach, Elsevier, Amsterdam, 1987. 

S. Aguerre, C. Pecheyran and G. Lespes, Validation, using a chemometric approach, of gas chromatography-inductively coupled plasma-atomic emission spectrometry (GC-ICP-AES) for organotin determination, Anal. Bioanal. Chem., 376(2), 2003, 226-235. 

Careri M, Furlattini L, Mangia A, Musci M, Anklam E, Theobald A and von Holst C, Supercritical fluid extraction for liquid chromatographic determination of carotenoids in Spirulinapacifica algae A chemometric approach. J ChromatogrA 912 61-71 (2001). 

Box, G.E.P., Hunter, W.G., Hunter, J.S. Statistics for Experimenters, Wiley, New York, 1978 Davies, L. Efficiency in Research, Development and Production The Statistical Design and Analysis of Chemical Experiments, Royal Society of Chemistry, Cambridge, 1993 Davies, O. L. (Ed.) The Design and Analysis of Industrial Experiments, Oliver and Boyd, London, 1984 Deming, S.N., Morgan, S.L. Experimental Design A Chemometric Approach, 2nd Ed., Elsevier, Amsterdam, 1993... 

Deming, S.N., Morgan, S.L. Experimental design A Chemometric Approach, 2nd Ed., Elsevier, Amsterdam, 1993... 

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