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Estimation of contribution

The effect has been observed for a variety of combustible materials, but no variations in charge to combustible mass, charge type, structure volume, or degree of venting have been tested. The implications of the data accumulated so far are that quasi-static loading calculations should include estimates of contributions from the burning of combustible materials whenever such materials are expected to be in intimate contact with HI sources. [Pg.18]

Matveev, Y. I., Elankin, N. Y., Kalistrova, E. N., Danilenko, A. N., Niemann, C., and Yuryev, V. P. (1998). Estimation of contributions of hydration and glass transition to heat capacity changes during melting of native starches in excess water. Starch/Starke 50, 141-147. [Pg.265]

It is important to note that such globally and annually averaged estimates of contributions to radiative forcing are not expected to be the sole measures of effects on climate. The inference may be mistakenly drawn that negative radiative forcing, e.g., through... [Pg.813]

Kuulasmaa, K., Tynstall-Pedoe, H., Dobson, A., Fortmann, S., Sans, S., Tolonen, H., Evans, A., Ferrario, M., Tuomilehto, J. 2000. Estimation of contribution of changes in classic risk factors to trends in coronary-event rates across the WHO MONICA project populations. Lancet. 355, 675-687. [Pg.635]

Fordyce JS, Sheibley DW. 1975. Estimate of contribution of jet aircraft operations to trace element concentration at or near airports. J Air Pollut Control Assoc 25 721-724. [Pg.103]

The estimation of contribution of common cause failures (CCF, (1) for the subsystems is made by following the simplified approach in 1EC62061 Annex F. [Pg.254]

Estimation of contribution to background scattering from analysis of Porod region (schematic). [Pg.228]

Lydersen, A.L. (1955), Estimation of critical properties of organic compounds by the method of group contributions . Uniu. Wisconsin Coll., Eng. Exp. Stn. report No. 4, Madison, Wl. [Pg.457]

In determining an estimate of reserves for an accumulation, all of the above parameters will be used. When constructing an expectation curve for STOIIP, GIIP, or ultimate recovery, a range of values for each input parameter should be used, as discussed in Section 6.2. In determining an appraisal plan, it is necessary to determine which of the parameters contributes most to the uncertainty in STOIIP, GIIP, or UR. [Pg.175]

It is possible that more than one of these drive mechanisms occur simultaneously the most common combination being gas cap drive and natural aquifer drive. Material balance techniques are applied to historic production data to estimate the contribution from each drive mechanism. [Pg.192]

We can now proceed with various estimates of the entropy of adsorption Two extreme positions are sometimes taken (see Ref. 14). First, one assumes that for localized adsorption the only contribution is the configurational entropy. Thus... [Pg.612]

Thus the entropy of localized adsorption can range widely, depending on whether the site is viewed as equivalent to a strong adsorption bond of negligible entropy or as a potential box plus a weak bond (see Ref. 12). In addition, estimates of AS ds should include possible surface vibrational contributions in the case of mobile adsorption, and all calculations are faced with possible contributions from a loss in rotational entropy on adsorption as well as from change in the adsorbent structure following adsorption (see Section XVI-4B). These uncertainties make it virtually impossible to affirm what the state of an adsorbed film is from entropy measurements alone for this, additional independent information about surface mobility and vibrational surface states is needed. (However, see Ref. 15 for a somewhat more optimistic conclusion.)... [Pg.613]

For large Cl calculations, the frill matrix is not fonned and stored in the computer s memory or on disk rather, direct CF methods [ ] identify and compute non-zero and inunediately add up contributions to the sum jCj. Iterative methods [, in which approximate values for the Cj coefficients are refined tlirough sequential application of to the preceding estimate of the vector, are employed to solve... [Pg.2177]

Estimates of Component Term for Conformation Adjustment and Cratic Contribution for Binding Benzene... [Pg.139]

The next step towards increasing the accuracy in estimating molecular properties is to use different contributions for atoms in different hybridi2ation states. This simple extension is sufficient to reproduce mean molecular polarizabilities to within 1-3 % of the experimental value. The estimation of mean molecular polarizabilities from atomic refractions has a long history, dating back to around 1911 [7], Miller and Sav-chik were the first to propose a method that considered atom hybridization in which each atom is characterized by its state of atomic hybridization [8]. They derived a formula for calculating these contributions on the basis of a theoretical interpretation of variational perturbation results and on the basis of molecular orbital theory. [Pg.322]

All three schemes, the Benson, the Laidler, and the Allen scheme, use four structure contributions for the estimation of thermochemical data of alkanes. As might be guessed, they are numerically equivalent all three schemes provide the same accuracy. This is shown below by Eqs. (7)-(10) for the interconversion of the various contributions. [Pg.325]

The use of group contribution methods for the estimation of properties of pure gases and Uquids [20, 21] and of phase equilibria [22] also has a long history in chemical engineering. [Pg.325]

The hydrophobic constant r is a measure of the contribution of a substituent X to the lipophilidty of compound R-X compared with R-H. The constant representing the solvent/solvent system, analogously to Hammett s p constant for the reaction type, was arbitrarily set to 1 for octanol/water and thus does not appear in Eq. (7). The lipophilidty constant ti allows the estimation of log P values for congeneric series of compounds with various substituents (see Eq. (8)). [Pg.492]

An extensive series of studies for the prediction of aqueous solubility has been reported in the literature, as summarized by Lipinski et al. [15] and jorgensen and Duffy [16]. These methods can be categorized into three types 1 correlation of solubility with experimentally determined physicochemical properties such as melting point and molecular volume 2) estimation of solubility by group contribution methods and 3) correlation of solubility with descriptors derived from the molecular structure by computational methods. The third approach has been proven to be particularly successful for the prediction of solubility because it does not need experimental descriptors and can therefore be applied to collections of virtual compounds also. [Pg.495]

Let us make an estimate of the order of magnitude of these effects. Referring to equation (9,23), the coefficient of the term relating the micropore contribution to and grad p is larger by a factor... [Pg.84]

Tlic cavity and van der Waals contributions may also be modelled as separate terms. In som implementations an estimate of the cavity term may be obtained using scaled particle theor [Eierotti 1965 Claverie et al. 1978], which uses an equation of the form ... [Pg.625]


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