The refractive index (n) is one of the most important optical properties that is frequently employed to characterize organic compounds.1 The refractive index is defined as a ratio of the velocity of light in a vacuum to the velocity of light in the substance of interest. It has been used as an indicator of the purity of organic compounds, but the relationship of refractive index to other optica...

In this paper, we defined a novel delta value di in molecular connectivity, and then obtained a novel kind of valence molecular connectivity index. The potential usefulness of the novel kind of valence molecular connectivity index in QSAR/QSPR is evaluated by its correlation with a number of molecules and by a favorable comparison with models based on molecular connectivity index. q 2003 Elsevi...

To relate structure and chromatographic retention an approach is needed that lacks the rigour of thermodynamics but which provides otherwise inaccessible information. Such an approach is a combination of detailed models with certain thermodynamic concepts. Linear free-energy relationships (LFER) may be regarded as linear relationships between the logarithms of the rate or equilibria constants f...

the quantitative structure-retention relationship (qsrr) of nanoparticles in roadside atmosphere against the comprehensive two-dimensional gas chromatography which was coupled to high-resolution time-of-flight mass spectrometry was studied. the genetic algorithm (ga) was employed to select the variables that resulted in the best-fitted models. after the variables were selected, the linear multi...

The performance of several previously designed model series of test analytes has been tested to characterize in an objective, quantitative manner modern stationary phases for reversed-phase high-performance liquid chromatography (RP-HPLC) using quantitative structure-retention relationships (QSRRs). Three QSRR approaches and three respective series of test analytes recommended for studies of th...

In this paper, we present a combination of a key-solute test based on retention and separation factors of large probe solutes (carotenoid pigments) and a quantitative structure-retention relationship analysis based on the retention factors of small probe solutes (aromatic compounds) to investigate the different chromatographic behavior of octadecylsiloxane-bonded stationary phases of all sorts:...

The retention time of 23 barbituric acid derivatives was determined on an narrow-bore porous graphitized carbon (PGC) column employing water-dioxane mixtures as mobile phases. The retention factor (k), theoretical plate number (N), and asymmetry factor (AF) were computed for each analyte in each mobile phase. Quantitative structure-retention relationship (QSRR) calculations using stepwise regre...