This index was applied to correlations with gas chromatographic retention index, boiling points, standard enthalpies of formation in gas phase, heats of solution, refractive indices, theoretically calculated total surface area of alkanes. [Pg.25]

From downhole pressure drawdown and build-up surveys the reservoir permeability, the well productivity index and completion skin can be measured. Any deviation from previous measurements or from the theoretically calculated values should be investigated to determine whether the cause should be treated. [Pg.340]

Reference intervals are numerically close to the normal intervals for total T4 or T3. Most automated immunoassay analyzers are capable of performing the THBR and total T4 tests with online calculation of the FT4 index. Theoretically, because the calculated indices are products of T4 or T3 concentrations and a ratio, they have concentration units. However, to avoid confusion with serum T4 or T3, the free hormone index units are usually omitted or termed index units. Typical values are as follows [Pg.2079]

Lee et al. separated 18 L-amino acids by RP-HPLC. Binding energy ( b), hydrophobicity (log P), molecular refractivity (MR), polarizability (a), total energy (E ), water solubility (log S), connectivity index (%) of different orders and Wiener index (W) were also theoretically calculated. The retention factors with various physicochemical and structural properties of L-amino acids were represented. After investigating the effect of descriptors on the retention factors, the live major ones were found to be E y, MR, Et, V, and W. The correlation coefficient was more than 0.95. [Pg.2359]

In practice, the elaborate measurements of dielectric constants of gases at different temperatures are usually circumvented, on the one hand by the use of dilute solutions and the application of additive relations for solvent and solute, and, on the other hand, by the theoretical calculation of a from the refractive index, so that /x can be found from measurements at one temperature only. [Pg.205]

With respect to the metal-adsorbate interaction it is of interest, for comparison with the experimental results, to develop theoretical calculations based on molecular models that involve the adsorbate molecules and a metal cluster. The INDO/1 semiempirical method has been proved to be very useful in the stmc-ture optimization and in the evaluation of the bond characteristics throughout the Wiberg index - ° The interaction of azamacrocycle complexes with simulated copper surfaces studied by the same method was performed - [Pg.782]

Several aromaticity indices (bond lengths, bond orders, Jug and Francois s aromaticity index) indicate that, despite the nonplanarity of the five-membered ring in 2,5-diphenylthiophene-l-oxide (108), this compound is intermediate in aromaticity between the corresponding thiophene 107 and the nonplanar 1,1-dioxide 109 (Scheme 48).149 The theoretical calculations were supported by experimental electrochemical data.150 [Pg.21]

This chapter is organized as follows. In Section 2, the basic definitions of the DFT descriptors are reminded, and the master equations that allow defining the new index are presented. The formal relation between the new index and the PMH is also discussed in Section 2. Section 3 deals with the computational details of the theoretical calculations presented and discussed in Section 4 where some classical organic reactions are studied in the light of the new reactivity-selectivity descriptor. Section 5 contains some concluding remarks. [Pg.103]

Values for the virial coefficients are derived from experimental measurements which can be conveniently classified as follows low pressnre p-V-T measnrements high pressnre p-V-T measnrements speed of sonnd measurements vaponr pressnre and enthalpy of vaporization measnrements refractive index/dielectric constant measurements and Jonle-Thomson experiments. These will be discussed in Chapter 1.2, and methods of data evalnation described in Chapter 1.5. Much attention has been paid to the correlation of virial coefficient data and the more satisfactory methods are considered in Chapter 1.3, together with a brief discussion of the theoretical calculation of the second virial coefficient from pair potential energy functions which have been derived a priori or by consideration of other dilute gas properties. So far, this calculation is only applicable to molecules with a spherically symmetric intermolecular potential energy function, for which [Pg.3]

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