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Order characterization

The difference compared to equation B 1.13.2 or equation B 1.13.3 is the occurrence of the expectation value of the operator (the two-spin order), characterized by its own decay rate pjg and coupled to the one-spin longitudinal operators by the tenus 8j aud 5. We shall come back to the physical origin of these tenus below. [Pg.1502]

Material flows that cross the balance area, i.e., they have either a source or a target outside of the organizational unit considered (sales orders, characterized by customer, quantity, material, requirements date purchase orders, characterized by vendor, quantity, material, availability date). [Pg.271]

According to Table 1, semi-invariants of higher order characterize the shape of the profile in terms of variance, skewness, and kurtosis. The outstanding merit of the Weibull distribution is that its shape parameter a provides a summarizing measure for this property. For other distributions, the characterization of the shape is less obvious. [Pg.258]

The fragments of macromolecules with ordered cholesterol group sequences, that are formed in bad solvents, may serve as nuclei of supermolecular order in films, obtained from these solvents. Structural and optical studies have shown that PChMA-11 films produced by solvent evaporation display different properties those obtained from chloroform and toluene solutions (small relaxation times, see Table 17) are optically isotropic, and those obtained from heptane solutions (large relaxation times, see Table 17) are optically anisotropic, what reflects the differences in conformational state of polymeric chains in these films. Contrary to the optically isotropic films, a high degree of side branch ordering characterizes optically anisotropic films, which is confirmed by X-ray studies. The observed difference of LC polymer structure in the bulk is thus the consequence of their different conformational state in solution this reveals some possibilities for the control of LC polymer structure at the initial steps of mesophase nucleation in solutions. [Pg.245]

Carbon-13 relaxation measurements have been covered in a number of texts (3, 23—25) and reviews. (26—30) For steroids it is clearly established that 13C relaxation is almost entirely due to interactions (dipole-dipole) with attached or nearby protons. (31-33) The relaxation process is kinetically first-order, characterized by a rate constant Tf1. For steroids, at useful concentrations, 13C T, values range from 0-02 to 5 s. Since Tt is markedly affected by molecular tumbling, it is necessary carefully to control and state solvents, concentrations, and temperatures in acquiring and reporting Tx values. Given all of these variables, Tx reproducibilities are usually found to be around 10%, while reports from different laboratories not infrequently differ by 20%. [Pg.203]

Let us define the distance of a system from global equilibrium by parameter ji (e.g., a temperature or a concentration gradient). After a value of /J, is reached, the system displays ordering characterized by a certain frequency or a wavelength. Figure 13.1 shows the bifurcation in the velocity in Bernard convection cells. If the parameter j8 is... [Pg.632]

We can observe that the equipment is characterized by the process parameters of first order whereas process parameters of second order characterize the processed materials. The first order and second order parameters are respectively called process parameters and non-process parameters . [Pg.4]

Interaction of CarbE with nerve agents follows a kinetic of first order characterized by inhibition of CarbE at the active site serine residue described by a bimolecular rate constant, ki (Maxwell and Brecht, 2001). For noncharged nerve agents (e.g. sarin and soman) the ki of rat serum CarbE was found to be >10 M min whereas cationic substrates (e.g. VX) are converted with poor reactivity (ki < 10" M min ). This specificity is explained by the electrostatic characteristics of the large active site containing only a few cation-II bonding and anionic residues (Maxwell and Brecht, 2001 Satoh and Hosokawa, 2006). [Pg.768]

Within a smectic layer, a state of order called hexatic can exist that is intermediate between the liquid order of the smectic A, and the crystalline order of crystalhne smectic B. This state of order characterizes the hexatic smectic-B phase. Flexatic order consists of long-range bond orientational order, but no long-range positional order. This is illustrated... [Pg.478]

Another well-established heterogeneous interface is that between the electrode surface and the electrolyte in electrochemistry, where there are regimes of various degrees of order, characterized by differing mass transport phenomena and involving different kinetic and thermodynamic requirements. Adsorption and surface phenomena are important and in general it has been recognized for some time that vibration of an electrochemical system can produce a variety of effects. [Pg.206]

The TT-donor and (3-hyperconjugation effects are present for both alkyl and vinyl carbocations. The vinyl carbocations exhibit somewhat larger stabilizations because they are inherently less stable. The vinyl cations also appear to be more sensitive to the a-polar effect. Note that the F, OH, and NH2 substituents are less stabilizing of vinyl cations than of alkyl cations. This is believed to be due to the greater sensitivity to the polar effect of the more electronegative sp carbon in the vinyl cations. The NPA and bond order characterizations of the carbocations are shown in Table 3.13. The values give the charge associated with the cationic carbon and the bond order between the cationic carbon and the substituent X. [Pg.305]

Table 3.13. NPA and Bond Order Characterizations of Substituted Carbocations... Table 3.13. NPA and Bond Order Characterizations of Substituted Carbocations...
Fig. 16 is casted into a simple but quantitative lattice algorithm. The basic idea is that individual chains successively increase their internal order (characterized by the degree of chain folding) during the crystallization process. The more the chain is ordered (the fewer folds it has) the lower is the surface area needed for this chain. The ultimate degree of order is represented by the completely stretched chain which only occupies a surface area proportional to the cross-section of one stem ao (area of a crystalUne unit cell), see Fig. 16. Let Ao be the area of the corresponding liquid chain, flatly adsorbed onto the surface. Then, M = Aq/ao N > 1 chains can occupy the same area Ao in the crystalUne state. By contrast, in a simple growth model [27] the area per particle remains constant and it is the original dilution of particles which is responsible for the various diffusion-controlled patterns [28,55]. Fig. 16 is casted into a simple but quantitative lattice algorithm. The basic idea is that individual chains successively increase their internal order (characterized by the degree of chain folding) during the crystallization process. The more the chain is ordered (the fewer folds it has) the lower is the surface area needed for this chain. The ultimate degree of order is represented by the completely stretched chain which only occupies a surface area proportional to the cross-section of one stem ao (area of a crystalUne unit cell), see Fig. 16. Let Ao be the area of the corresponding liquid chain, flatly adsorbed onto the surface. Then, M = Aq/ao N > 1 chains can occupy the same area Ao in the crystalUne state. By contrast, in a simple growth model [27] the area per particle remains constant and it is the original dilution of particles which is responsible for the various diffusion-controlled patterns [28,55].
Local order characterized by pair distribution functions (derived from electron scattering traces),... [Pg.204]


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See also in sourсe #XX -- [ Pg.294 ]




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