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Method linearity

We now discuss the most important theoretical methods developed thus far the augmented plane wave (APW) and the Korringa-Kolm-Rostoker (KKR) methods, as well as the linear methods (linear APW (LAPW), the linear miiflfm-tin orbital [LMTO] and the projector-augmented wave [PAW]) methods. [Pg.2210]

FIG. 3-53 Trial functions for Galerldn finite element method linear polynomial on triangle. [Pg.481]

External standard method (linear calibration curve of peak areas)... [Pg.173]

Approximate construction of the manifolds in the neighborhood of these objects through local methods -linear and perhaps higher order (20). [Pg.291]

The chapters have been organized in such a way that, after basic principles have been introduced (Mass Balance), modeling methods (Linear Algebra, Numerical Analysis, Probability and Statistics) are presented before more specifically geochemical... [Pg.562]

A typical chromatogram representing the separation of Hypericum perforatum extract with the HPLC-MS attributions of the components detected is shown in Fig. 2.49. The validation parameters of the method (linearity, stability, reproducibility of the injection integration and repeatability, and robustness) were acceptable, therefore, it was found suitable for routine analysis of the composaition of the extracts of Hypericum perforatum [149],... [Pg.163]

The procedure is repeated until the procedure converges, that is until the correction vector b approaches zero. Methods of modifying the size of the correction vector have been developed to improve convergence (B5) and this method, in theory, should always converge (HI). In practice, nonlinearities in the model and poor parameter estimates can prevent convergence. A modification of this method linearizes the normal equations higher derivatives have also been used. [Pg.116]

Method Linear Parameters to Optimize Direct Use in High Dimensions Data Need to Be Autoscaled... [Pg.260]

Diynes have already been used for building polycylic compounds in the presence of CO2 and a stoichiometric amount of Ni(0) bicyclic pyrones were obtained [117]. With the electrocarboxylation method, linear or cyclic mono-carboxylic acids were obtained as main products from non-conjugated diynes depending on the ligand associated to Ni [118, 119]. Thus ring-fomation occurred with the Ni-bipyridine complex at normal pressure of CO2 on the other hand, in the presence of PMDTA as ligand and with a 5 atmosphere pressure of CO2, linear adducts were mainly formed as illustrated in Eq. (16) ... [Pg.165]

Report Method Name Method Linearity Report... [Pg.298]

X.-P. Li, R. W. Nunes, and D. Vanderbilt, Density-matrix electronic-structure method linear system-size scaling. Phys. Rev. B 47, 10891 (1993). [Pg.202]

Execution of the method validation protocol should be carefully planned to optimize the resources and time required to complete the full validation study. For example, in the validation of an assay method, linearity and accuracy may be validated at the same time as both experiments can use the same standard solutions. A normal validation protocol should contain the following contents at a minimum ... [Pg.737]

Figures 9.1-9.3 illustrate these interconnected relationships.13 Figure 9.1 defines some of the terms used in this chapter. Small molecules are species with molecular weights below about 1,000. They are volatile at temperatures below say 200 100 °C. Clusters are oligomers derived from covalently linked small molecules. They have a lower volatility than small molecules and, if large enough, can be shaped by melting or by solvent evaporation methods. Linear polymers can be simple chain structures or may consist of rings linked together. In either case they are usually non-volatile and easily fabricated. Cross-linked systems can be produced from polymers or from clusters. The final ceramic may be amorphous or crystalline. Figures 9.1-9.3 illustrate these interconnected relationships.13 Figure 9.1 defines some of the terms used in this chapter. Small molecules are species with molecular weights below about 1,000. They are volatile at temperatures below say 200 100 °C. Clusters are oligomers derived from covalently linked small molecules. They have a lower volatility than small molecules and, if large enough, can be shaped by melting or by solvent evaporation methods. Linear polymers can be simple chain structures or may consist of rings linked together. In either case they are usually non-volatile and easily fabricated. Cross-linked systems can be produced from polymers or from clusters. The final ceramic may be amorphous or crystalline.
More recently, Brennan et al. (1997) compared five methods for estimating KAW, namely the vapor pressure/solubility ratio, the group or bond contribution method, linear solvation energy methods, and molecular connectivity. The authors compared the methods by application to a common set of 150 chemicals and concluded that the Meylan and Howard (1991) bond contribution method and the molecular connectivity index method of Nirma-lakhandan and Speece (1988) are comparably accurate, having standard deviations of, 0.29 and 0.34 log units, respectively. [Pg.96]

As said before, linear models are used to reach (move towards) optimum, so that the significance of regression coefficients is an assumption for successful application of the steepest ascent method. Linear models, therefore, include as many factors as possible, and full factorial experiments are even replicated with increased factor variation intervals. [Pg.366]

Regression methods (linear or non-linear) are used to determine an EC value that produces a specific percent reduction (e.g. 10, 20 or 50%) in an assessment endpoint. [Pg.355]

Multiple regression method Linear regression using several variables. Volume 2(2). [Pg.398]

There are a variety of methods for the computation of the MOs that interact in the transition states of [4+2]-cycloadditions. The LCAO method (linear combination of atomic orbitals) is often employed, and the basic idea is as follows. The MOs of the -systems of alkenes, conjugated polyenes, or conjugated polyenyl cations, radicals, or anions all are built by so-called linear combinations of 2p AOs. In a somewhat casual formulation, one might say that the MOs of these -systems are constructed with the help of the 2pz AOs. These AOs are centered at the positions of the n C atoms that are part of the -system. LCAO computations describe a conjugated -electron system that extends over n s/ 2-hybridized C atoms by way of n Ji-type MOs. [Pg.646]

These efforts were guided by the study of quantitative structure-activity relationships (QSAR) following the Hansch approach. In this method linear free-energy related and other electronic, hydrophobic, and steric substituent constants are used for a quantitative analysis of the possible ways in which substituents may modulate bioactivity in a congeneric series. In the QSAR studies of benzoylphenyl ureas the electronic Hammett a-constants and the hydro-phobic Hansch n-constants were used. To measure the steric influences, steric substituent constants of a new type (B1,B2,B3,B4, and L) were applied which had recently been introduced by us and which give improved correlations in comparison with the steric Es constants used in the literature hitherto (21, 22). The constants B- toBj are measures of the widths of substituents in four rectangular directions. The L-constant accounts for the length of a substituent ... [Pg.236]

Electronic structure methods for studies of nanostructures can be divided broadly into supercell methods and real-space methods. Supercell methods use standard k-space electronic structure techniques separating periodically repeated nanostructures by distances large enough to neglect their interactions. Direct space methods do not need to use periodic boundary conditions. Various electronic structure methods are developed and applied using both approaches. In this section we will shortly discuss few popular but powerful electronic structure methods the pseudopotential method, linear muffin-tin orbital and related methods, and tight-binding methods. [Pg.15]

In this section, we present a novel linearization method for simplifying the nonlinear Poisson-Boltzmann equation to derive an accurate analytic expression for the interaction energy between two parallel similar plates in a symmetrical electrolyte solution [13, 14]. This method is different from the usual linearization method (i.e., the Debye-Hiickel linearization approximation) in that the Poisson-Boltzmann equation in this method is linearized with respect to the deviation of the electric potential from the surface potential so that this approximation is good for small particle separations, while in the usual method, linearization is made with respect to the potential itself so that this approximation is good for low potentials. [Pg.231]

S. Yiantsios and B.G. Higgins, Analysis of superposed fluids by the finite element method linear stability and flow developement, Int. J. Numer. Meth. Fluids, 7 (1987) 247-261. [Pg.235]

For comparison with the flame simulations, the relative CH and CN concentration profiles along the centerline of the burner were recorded followed by a calibration of the relative concentration profiles using a N2 Rayleigh calibration method. Linear LIF was used to determine the CH and CN signal intensities as a function of height above the burner. In this case the relationship between the detected LIF intensity /lip and, e.g. the CH number density Nqh is given by... [Pg.220]


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See also in sourсe #XX -- [ Pg.231 ]




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