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Substitution defined

The normalized plane strain procedure therefore requires the same modest computational resources as the ordinary plane strain model. Furthermore, the same algorithms used for the ordinary plane strain model can he employed, since the revised model simply requires the substitutions defined by Equations 7 and 8. [Pg.18]

The enumeration process takes a generic structure and performs the substitutions defined by one or more of the R-groups to generate a number of more specific structures. [Pg.268]

Enzymatic phosphorylation by phosphorylases and phosphatases produces phosphoesters such as phosphoserine and phosphothreonine. Chemical phosphorylation of proteins changes their functional properties, improving them sometimes (Yoshikawa et al., 1981 Hirotsuka et al., 1984 Huang and Kinsella, 1986 Chobert etal, 1989 Matheis, 1991). However, the properties of the phosphorylated proteins depend entirely on the degree of denaturation and substitution defined by the reaction conditions and the protein (Medina etal, 1992 Sitohy etal, 1994). Casein was phosphorylated by the commonly used methods, characterized by use of excessive amounts of phosphorus oxychloride and with important additions of concentrated inorganic bases (Matheis et al, 1983 Medina et al, 1992). Thus, obtained phosphorylated caseins were highly cross-linked and partially insoluble and difficult to characterize. Hence, there arose a need to produce monomeric over-phosphorylated caseins more suitable for use and for study of their... [Pg.4]

This discussion provides an overview of the methods for selecting a serum lot and balanced nutrient medium as starting points for adapting a cultured cell line to serum-free conditions. The ultimate stringency of serum-free medium attained (containing serum substitutes, defined additives or protein-free) depends on the needs of the researcher and the characteristics of the cell line. Serum provides many different functions for the cell and there are many different types of cells, each of which requires a medium derived to meet its particular needs. The information provided here should enable the development of a serum-free medium appropriate for each particular case. [Pg.97]

Let us now take the product Xi(R)Yi(p aoi) to represent the molecular wave function j(p,R). This substitution defines the rigged BO scheme. [Pg.111]

After making the appropriate substitutions defined pre- derivation just described is predicated on r and being viously independent. However, consider the model... [Pg.229]

Case 1. All the diagonal (pivot) entries are nonzero the triangular system has exactly r equations, r = rank (A) < n. In that case, x +i,..., are free variables for an arbitrary set of their values, back substitution defines unique set of values of Xi,..., satisfying the original system of Eq. (1), (compare Theorem 1). If r = n, the system ofEq. (1) is nonsingular and has a unique solution. [Pg.184]

The pseudo-bond graph model of the system, in the preferred derivative causality, is given in Fig. 7.17. The pressures and the mass flow rates have been considered as the generalized effort and flow variables, respectively. Performing the substitutions defined before, we obtain a model shown in Fig. 7.18, which is called a diagnostic bond graph (DBG) model [3,4],... [Pg.248]

Now, substitute defining expressions for fl and //, using the subscripts /and i to indicate final and initial, respectively. Note, however, that the pressure is constant. [Pg.768]

By differentiating the defining equations for H, A and G and combining the results with equation (A2.T25) and equation (A2.T27) for dU and U (which are repeated here) one obtains general expressions for the differentials dH, dA, dG and others. One differentiates the defined quantities on the left-hand side of equation (A2.1.34), equation (A2.1.35), equation (A2.1.36), equation (A2.1.37), equation (A2.1.38) and equation (A2.1.39) and then substitutes die right-hand side of equation (A2.1.33) to obtain the appropriate differential. These are examples of Legendre transformations. ... [Pg.347]

The use of isotopic substitution to detennine stmctures relies on the assumption that different isotopomers have the same stmcture. This is not nearly as reliable for Van der Waals complexes as for chemically bound molecules. In particular, substituting D for H in a hydride complex can often change the amplitudes of bending vibrations substantially under such circumstances, the idea that the complex has a single stmcture is no longer appropriate and it is necessary to think instead of motion on the complete potential energy surface a well defined equilibrium stmcture may still exist, but knowledge of it does not constitute an adequate description of the complex. [Pg.2441]

This wave equation is tire basis of all wave optics and defines tire fimdamental stmcture of electromagnetic tlieory witli tire scalar function U representing any of tire components of tire vector functions E and H. (Note tliat equation (C2.15.5) can be easily derived by taking tire curl of equation (C2.15.1) and equation (C2.15.2) and substituting relations (C2.15.3) and (C2.15.4) into tire results.)... [Pg.2854]

It is expected that for a certain choice of paiameters (that define the x matrix) the adiabatic-to-diabatic transformation matrix becomes identical to the corresponding Wigner rotation matrix. To see the connection, we substitute Eq. (51) in Eq. (28) and assume A( o) to be the unity matrix. [Pg.686]

In order to allow any multiple chlorination of the biphenyl skeleton, the user may define an atom list (eonsisting of hydrogen and chlorine atoms) and substitute all H-atoms by this list. One may click on the drop-down selection box behind the element icons, select the options Generics. .set the user-defined atom to A1 and quit by the OK button. As a result this atom selection is active for the subsequent drawing steps. After this atom list is drawn ten times as the ten substituents, its composition has to be defined by clicking the A, icon on the left-hand side of the structure editor and by selecting H and Cl in the periodic table (Figure 5-16). [Pg.250]

Structural keys describe the chemical composition and structural motifs of molecules represented as a Boolean array. If a certain structural feature is present in a molecule or a substructure, a particular bit is set to 1 (true), otherwise to 0 (false). A bit in this array may encode a particular functional group (such as a carboxylic acid or an amidelinkage), a structural element (e.g., a substituted cyclohexane), or at least n occurrences of a particular element (e.g., a carbon atom). Alternatively, the structural key can be defined as an array of integers where the elements of this array contain the frequency of a specific feature in the molecule. [Pg.403]

Non-dimensionalization of the stress is achieved via the components of the rate of deformation tensor which depend on the defined non-dimensional velocity and length variables. The selected scaling for the pressure is such that the pressure gradient balances the viscous shear stre.ss. After substitution of the non-dimensional variables into the equation of continuity it can be divided through by ieLr U). Note that in the following for simplicity of writing the broken over bar on tire non-dimensional variables is dropped. [Pg.177]

This group comprises substances of the tjrpe RCONHR and RCONR R", i.e., substituted amides of the aromatic series. They are all well-defined crystalline sohds, sparingly soluble in cold but, often, appreciably soluble hi hot water and moderately soluble in ether they are generally neutral or feebly basic in reaction. [Pg.801]

To simplify the analysis of the above CSFs, the familiar homonuelear ease in whieh z = 1.0 will be examined first. The proeess of substituting the above expressions for a and a into the Slater determinants that define the singlet and triplet CSFs ean be illustrated as follows ... [Pg.301]

The more extensive problem of correlating substituent effects in electrophilic substitution by a two-parameter equation has been examined by Brown and his co-workers. In order to define a new set of substituent constants. Brown chose as a model reaction the solvolysis of substituted dimethylphenylcarbinyl chlorides in 90% aq. acetone. In the case ofp-substituted compounds, the transition state, represented by the following resonance structures, is stabilized by direct resonance interaction between the substituent and the site of reaction. [Pg.138]

A plot against Hammett s cr-constants of the logarithms of the rate constants for the solvolysis of a series of Mz-substituted dimethylphenylcarbinyl chlorides, in which compounds direct resonance interaction with the substituent is not possible, yielded a reasonably straight line and gave a value for the reaction constant (p) of — 4 54. Using this value of the reaction constant, and with the data for the rates of solvolysis, a new set of substituent parameters (cr+) was defined. The procedure described above for the definition of cr+, was adopted for... [Pg.138]

The selectivity relationship merely expresses the proportionality between intermolecular and intramolecular selectivities in electrophilic substitution, and it is not surprising that these quantities should be related. There are examples of related reactions in which connections between selectivity and reactivity have been demonstrated. For example, the ratio of the rates of reaction with the azide anion and water of the triphenylmethyl, diphenylmethyl and tert-butyl carbonium ions were 2-8x10 , 2-4x10 and 3-9 respectively the selectivities of the ions decrease as the reactivities increase. The existence, under very restricted and closely related conditions, of a relationship between reactivity and selectivity in the reactions mentioned above, does not permit the assumption that a similar relationship holds over the wide range of different electrophilic aromatic substitutions. In these substitution reactions a difficulty arises in defining the concept of reactivity it is not sufficient to assume that the reactivity of an electrophile is related... [Pg.141]

These and other studies of the relative substituent effects of X and CH X in nitration were considered in terms of the transmission factor a of the methylene group. To avoid complications from conjugative interactions, attention was focussed mainly on substitution at the meta-position, and ct was defined in terms of partial rate factors by the equation ... [Pg.227]


See other pages where Substitution defined is mentioned: [Pg.85]    [Pg.202]    [Pg.278]    [Pg.200]    [Pg.3]    [Pg.363]    [Pg.226]    [Pg.220]    [Pg.1817]    [Pg.107]    [Pg.86]    [Pg.85]    [Pg.202]    [Pg.278]    [Pg.200]    [Pg.3]    [Pg.363]    [Pg.226]    [Pg.220]    [Pg.1817]    [Pg.107]    [Pg.86]    [Pg.41]    [Pg.241]    [Pg.656]    [Pg.1076]    [Pg.1923]    [Pg.2441]    [Pg.7]    [Pg.659]    [Pg.350]    [Pg.254]    [Pg.569]    [Pg.41]    [Pg.49]    [Pg.29]    [Pg.324]    [Pg.11]    [Pg.96]   
See also in sourсe #XX -- [ Pg.27 ]




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Allylic substitution defined

Ligand substitutions defined

Nucleophilic acyl substitution defined

Nucleophilic substitution defined

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