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Linear, generally method

In the second general method, the amine (16), known as Grewe diamine, is the paradigm intermediate onto which the thia2o1ium ring is constmcted. Differences occur only in the raw materials and methods used for the manufacture of the diamine. The same end of the linear sequence is universally practiced by all large manufacturers. [Pg.89]

Partial least-squares path modeling with latent variables (PLS), a newer, general method of handling regression problems, is finding wide apphcation in chemometrics. This method allows the relations between many blocks of data ie, data matrices, to be characterized (32—36). Linear and multiple regression techniques can be considered special cases of the PLS method. [Pg.426]

X Chen, A Tropsha. A generalized linear response method Application to the hydration free energy calculations. J Comput Chem 20 749-759, 1999. [Pg.368]

Cropley made general recommendations to develop kinetic models for compUcated rate expressions. His approach includes first formulating a hyperbolic non-linear model in dimensionless form by linear statistical methods. This way, essential terms are identified and others are rejected, to reduce the number of unknown parameters. Only toward the end when model is reduced to the essential parts is non-linear estimation of parameters involved. His ten steps are summarized below. Their basis is a set of rate data measured in a recycle reactor using a sixteen experiment fractional factorial experimental design at two levels in five variables, with additional three repeated centerpoints. To these are added two outlier... [Pg.140]

Relaxation data may be analyzed by two general methods a two-parameter, linear regression and a three-parameter, nonlinear, fitting procedure. " " The first method requires an accurate experimental determination of Mo, which is both difficult and time-consuming. Furthermore, the... [Pg.142]

Linear Differential Equations Right-Hand Member t(x) 0 Again the specific remarks for y" + ay + by =flx) apply to differential equations of similar type but higher order. We shall discuss two general methods. [Pg.31]

The synthesis of other angularly fused triquinanes as well as linearly fused sesquiterpenes such as hirsutene and capnellene quickly followed. Many general methods for the synthesis of cyclopentanoid natural products emerged as a result of the target-oriented effort [6]. These accomplishments have been reviewed extensively on numerous occasions [7]. This chapter reviews the history of retigeranic acid from its isolation and structure determination to published approaches to its synthesis and the four total syntheses accomplished to date. [Pg.236]

Although Wender s synthesis was completed prior to Hudlicky s, it was published later [65]. It utilized the technique of mefa-photocycloaddition of arenes that Wender developed into a general method of synthesis for both angular and linear triquinanes. The overall strategy was centered around an intramolecular Diels-Alder cycloaddition for construction of the internal six-membered ring of the target. [Pg.252]

A more general method for preparing carbenes often involves the a elimination of halides from carbanions.1-57 PAC can be used to examine the rates and energetics of the reverse reactions, the complexation of halides with carbenes (Fig. 5).58 Plots of A//com versus the proton affinities (PA) of the halides are linear for the two carbenes studied. Although the slopes of the plots are similar, complexation of the halides with phenylchlorocarbene is more exothermic than phenylfluorocarbene. This indicates that fluoro substitution stabilizes the carbene relative to the carbanion more than chloro substitution. The rate of complexation of carbenes with salts has also been examined by nanosecond absorption spectroscopy.59... [Pg.264]

The interest in reformulating the conserved-variable scalars in terms of the mixture-fraction vector lies in the fact that relatively simple forms for the mixture-fraction PDF can be employed to describe the reacting scalars. However, if < /Vmf, then the incentive is greatly diminished since more mixture-fraction-component transport equations (Nmf) would have to be solved than conserved-variable-scalar transport equations (/V, << ). We will thus assume that N m = Nmf and seek to define the mixture-fraction vector only for this case. Nonetheless, in order for the mixture-fraction PDF method to be applicable to the reacting scalars, they must form a linear mixture defined in terms of the components of the mixture-fraction vector. In some cases, the existence of linear mixtures is evident from the initial/inlet conditions however, this need not always be the case. Thus, in this section, a general method for defining the mixture-fraction vector in terms of a linear-mixture basis for arbitrary initial/inlet conditions is developed. [Pg.180]

A graft copolymer consists of a linear Polymer chain of one type to which has been grafted side-chains of a different type of polymer. The formation of a graft copolymer can be brought about by either of two general methods ... [Pg.56]

MLR Multiple linear regression (used as general term for all linear regression methods like OLS, PLS, PCR)... [Pg.308]

Method validation is the process of proving that an analytical method is acceptable for its intended purpose. Many organizations provide a framework for performing such validations (ASTM, 2004). In general, methods for product specifications and regulatory submission must include studies on specificity, linearity, accuracy, precision, range, detection limit, and quantitation limit. [Pg.174]

SOPPA(CCSD) calculations with the CCSD or MCSCF PEC are also larger. In general the differences in the ZPVC are larger between the different PEC than between the different linear response methods. The SOPPA(CCSD) results for the equilibrium geometry as well as the vibrationally averaged polarizabilities are in both molecules in better agreement with the MCSCF results than the pure SOPPA values. [Pg.206]

In general, linear functions and correspondingly linear optimization methods can be distinguished from nonlinear optimization problems. The former, being in itself the wide field of linear programming with the predominant Simplex algorithm for routine solution [75] shall be excluded here. [Pg.69]

The optical rotation of the mixture approaches zero (a racemic mixture) over time, with apparent first-order kinetics. This observation was supported by the semi-log plot [ln(a°D/ aD) vs time], which is linear (Figure 1). It has been shown that this racemization process does in fact follow a true pseudo-first-order rate equation, the details of which have been described by Eliel.t30 Therefore, these processes can be described by the first-order rate constant associated with them, which reflects precisely the intrinsic rate of racemization. Comparison of the half-lives for racemization under conditions of varying amino acid side chain, base, and solvent is the basis for this new general method. [Pg.664]

The general method for the determination of the flat band potential is based on the Mott-Schottky linear plot based on ca-pacitance/voltage relation. Starting from Eq. (9) the space charge distribution was calculated, and its potential dependence lead to the derivation of a model equivalent to a capacitance, given by ... [Pg.311]

Three general methods have been employed for the synthesis of such molecules, all of them depending on cyclization of an appropriate linear precursor. [Pg.270]


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See also in sourсe #XX -- [ Pg.112 ]




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Linear General

Linear methods

Linearized methods

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