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Theoretical Prerequisites

In the classical approximation mentioned in the previous section, the moment of transition, M , is formed as a vector sum from the amplitudes of deviation for the atoms involved in /-vibration [6,7]. In this way, it is determined to be, with respect to a coordinate system, associated with the molecule. For the oriented molecules of a given compound studied, however, the direction of M is defined toward the director n, originating from the macroscopic orientation of the molecular assembly. [Pg.3]

Bear in mind toat the plane of the linearly polarized irradiation is oriented along the z axis and Myp- and (M are proportional to the absorptions, corresponding to the t-band in the parallel (A ) and the perpendicular (Ap spectrum. [Pg.5]

According to Equation 1.16, the mutual orientation of M, and the director n concluding angle of 45° corresponds to the dichroic ratio D = 1, which means that the intensity of the band i should be the same in the parallel as well as in the perpendicular IR-LD spectrum. This, however, is not in fact the case, since A and A, actually become equal at the magic angle of 54.7°. [Pg.5]

Fignre 1.3 is associated with the moment of transition M oriented at an angle 0 with the axis z in a coordinate system, along which the long molecular axis is oriented. If the director n coincides with the z axis of laboratory coordinate system [Pg.5]

FIGURE 1.3 M,. involved in the conclusion of angle 9 with the z axis. [Pg.6]


The investigation of PCSs was based upon the theoretical prerequisites of the conjugation concept. This concept, developed on the basis of theoretical analysis and experimental studies of the properties of compounds with low molecular weights, has played an essential role in the progress of our understanding of the nature of the chemical bond, structure, and the reactivity of substances. [Pg.2]

ON THE THEORETICAL PREREQUISITES FOR APPLICATION OF NOVEL MATERIALS IN PROMISING ENERGY SYSTEMS... [Pg.311]

Some theoretical prerequisites for application of modified and expanded graphites, Si- and Sn-based composites and alloys, electroconducting polymers as active materials, catalysts and electro-conductive additives for lithium - ion batteries, metal-air batteries and electrochemical capacitors are considered. The models and the main concepts of battery-related use for such materials are proposed. [Pg.311]

Langacker, R. W. (1987). Foundations of cognitive grammar, vol. 1 Theoretical prerequisites. Stanford Stanford University Press. [Pg.321]

To determine the corresponding coefficients for heat and mass transfer we need some theoretical prerequisites which were introduced already in sect 1.3.4. However, it might be convenient to examine and partly repeat certain relationships before we proceed to the next section. [Pg.627]

Calculations performed by Schulze et al. (1989) are well known along with the theory described in Sections 11.1 - 11.7. General theoretical prerequisites of these investigations coincide in many respects. [Pg.566]

It is an experimental fact that the Arrhenius equation is applicable to bioprocesses. A theoretical prerequisite for the Arrhenius equation is well known—that the velocities of, for example, gas particles follow a Boltzmann distribution. The distribution becomes narrower with increasing molecular weight, so that in the case of enzymes and cells it barely exists. Without the theoretical background, application of the Arrhenius equation to a microbiological processes must be considered a formal kinetic procedure with appropriate fitting parameters. [Pg.201]

First, chain chemical reactions belong to the class of reactions for which the general kinetic laws are studied in detail and the theoretical fundamentals are formulated on the whole. It is thought that the possibilities of the theoretical prerequisites of the value method will be more clearly highlighted against this background. [Pg.93]

Theoretical Prerequisites of Fa/ue Analysis of Critical Phenomena in Branching Chain Reactions... [Pg.102]

In order for an experimental test of the kinetic behaviour to be as informative as possible, the system investigated should fulfil various specific requirements. From the experimental point of view, the reaction should cause a minimum of change in the reaction medium and be without side-reactions as far as possible, in order for accurate and well-defined rate measurements to be feasible. For the same reason an accOTate physical method which can be applied without distiubing the reacting system is to be preferred. From the theoretical point of view, it is desirable that the steric effects play as important a role in the reaction as possible, because only then is a sizeable effect to be expected. Finally, a transition state of well-known conformation is a necessary prerequisite for the quantitative application of the theory. [Pg.4]

Not until the 1940 s did suitable methods, both experimental and theoretical, become available for reducing the constitution of polymers, including the nonlinear, network-forming types, to tractable quantitative terms. Since such means are a prerequisite to the quantitative treatment of polymer properties in relation to constitution, advances in this direction necessarily were delayed. [Pg.25]

Equations (1-3) are widely used for protein dynamics analysis from relaxation measurements. The primary goals here are (A) to measure the spectral densities J(co) and, most important, (B) to translate them into an adequate picture of protein dynamics. The latter goal requires adequate theoretical models of motion that could be obtained from comparison with molecular dynamics simulations (see for example Ref. [23]). However, accurate analysis of experimental data is an essential prerequisite for such a comparison. [Pg.288]

Since the characterization of the overall rotational diffusion is a prerequisite for a proper analysis of protein dynamics from spin-relaxation data, we first focus on the theoretical basis of the method being used. [Pg.293]

In fact after more than 60 years, hydroformylation is at the beginning of a new epoch leaving bulk chemistry and entering speciality and fine chemistry. Further networking of different professionals such as organometallic chemists, theoretical chemists, and engineers will be a prerequisite for success. [Pg.41]

If the economist s question is asked, it is often assumed that it is unlikely that organic farming as a fixed system coincides in respect to environmental performance with the aspiration level of society for each indicator (Alvensleben 1998). This point of view follows the Tinbergen rule of economic theory that tells us that the number of policy instruments chosen should at least equal to the number of targets set (Ahrens and Lippert 1994, Henrichsmeyer and Witzke 1994). This is theoretically sound if the following prerequisites are given ... [Pg.94]

ILs can also serve as tools for the MS itself. The introduchon of the ILMs for MALDI MS has opened the way to a number of new applicahons for this method. A number of theoretical studies are necessary in order to fully understand the properties of the ILMs [36]. The basic processes of IL-MALDI are still only partially understood. Therefore, basic work remains to be done to explain theoretical aspects. The wide field of already indicated and other shll unknown applications of the ILM seems to legitimate these efforts. Up to now, no consistent relationships have been found between the composition of an ILM and its ability to serve as a good matrix—a situahon which is comparable to all other substances used as matrices. A deeper understanding of the theoretical background of the ILM is the prerequisite for a possible tailor-made creation of new matrices in the future. [Pg.392]


See other pages where Theoretical Prerequisites is mentioned: [Pg.31]    [Pg.649]    [Pg.114]    [Pg.3]    [Pg.31]    [Pg.649]    [Pg.114]    [Pg.3]    [Pg.438]    [Pg.440]    [Pg.844]    [Pg.4]    [Pg.106]    [Pg.119]    [Pg.118]    [Pg.63]    [Pg.212]    [Pg.418]    [Pg.50]    [Pg.39]    [Pg.95]    [Pg.53]    [Pg.613]    [Pg.3]    [Pg.602]    [Pg.83]    [Pg.355]    [Pg.126]    [Pg.771]    [Pg.194]   


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