Optimum molecular structure

The molecular energy at the fixed geometry represents a point of the adiabatic potential (AP), E. An optimum molecular structure is received after geometry optimisation (a systematic search for the AP minimum). In the minimum the gradient of the AP vanishes, and the... 

Very useful information is provided by the calculated kinetic trajectories of the value contributions of individual steps, for the cases when a stimulator or inhibitor with optimum molecular structure participates in a reaction. Ranking the steps by the contribution of reactions with participation of stimulators, inhibitors and their intermediates, enables to answer the question what reaction or reactions namely play the dominant role, and finally to determine the structure of the most efficient stimulator or inhibitor. 

We are left with the question as to what, in relation to mixing in an internal mixer, is the optimum molecular structure of the pure rubber. As with most questions in rubber technology, there is no straightforward answer. The level of carbon black dispersion is important for the further processing of the mixtures (e.g., extrusion) and for the appearance and the mechanical properties of the vulcanized products. The level of carbon black dispersion in the plateaus observed is 95%, which is amply sufficient for many applications. 

Although LOX from soybean seed is the best characterized of plant LOXs, this enzyme is present in a wide variety of plant and animal tissues (Liavonchanka and Feussner, 2006). The enzyme occurs in a variety of isoenzymes, which often vary in their optimum pH and in product and substrate specificity. Given the occurrence of multiple LOX isoenzymes in soybean leaves and the proposed roles of these enzymes in the plant metabolism, it is possible that individual isoenzymes play specific functions (Feussner and Wasternack 2002). The molecular structure of soybean LOX is the most reported, and four isoenzymes have been isolated (Baysal and Demirdoven 2007). Soy isoenzyme 1 produces 9- and 13-hydroperoxides (1 9) when the enzyme acts on free PUFA at pH 9.0, its optimum pH (Lopez-Nicolas and others 1999). Soy isoenzyme 2 acts on triglycerides as well as free PUFA leading to 9- and 13-hydroperoxide... 

Owing to differences in their molecular structure, the various antioxidants exhibit substantial differences in effectiveness when used with different types of foodstuffs and when used under different processing and handling conditions.2 The problem of selecting the optimum antioxidant or combination of antioxidants is further complicated by the difficulty of predicting how the... 

Effect of 6- Caprolactone and Adipic Acid Molar Ratio for Copolyester III on the Hydrolysis by R. delemar Lipase. The hydrolysis of various copolymers by R. delemar lipase was exam ed to see whether there was an optimum chemical structure or not. Mn of those copolyesters was selected from 17 0 to 2220, to diminish the effect of molecular weight. Optimum molar ratio of e- caprolactone and adipic acid was about from 90 10 to 70 30 (Figure 5). The Tm at the optimum molar ratio was the lowest of all. So it seemed that the existence of optimum molar ratio came from the lowest Tm, which would show the most amorphous material, rather than the optimum chemical structure. 

The polyesterification reaction is reversible because it is influenced by the presence of condensate water in equilibrium with the reactants and the polymer. The removal of water in the latter part of the reaction process is essential for the development of optimum molecular weight, on which the ultimate structural performance depends. 

In a review of the thermodynamics of water, Franks and Reid (1973) showed that the optimum molecular size range for maximum solubility was similar to hydrate stability. Franks and Reid noted, this is not intended to imply that long-lived clathrate structures exist in solution—only that the stabilization of the water structure by the apolar solutes resembles the stabilization of water in a clathrate lattice. Glew (1962) noted that, within experimental error, the heat of solution for ten hydrate formers (including methane, ethane, propane, and hydrogen sulfide) was the same as the heat of hydrate formation from gas and ice, thereby suggesting the coordination of the aqueous solute with surrounding water molecules. 

The most conceptually attractive model for these solutions is to consider that the organization of water resembles that in the clathrate hydrates (p. 225), the structure being based on pentagonal dodecahedra of hydrogen bonded water molecules (Glew and Moelwyn-Hughes, 1953). This model receives some support from the observation that there is an optimum molecular radius of 4-5 x 10 8 cm for solubility of apolar solutes in water (Franks and Reid, 1973). 

Structures and substitution patterns of bridge elements in ID tt systems conjugation efficiency. The electronic requirements for optimum molecular second-order polarizabilities devised on the basis of the two-state model (see pp. 143 and 168) and the technical requirements to translate molecular properties into stable bulk materials partially coincide with the requirements for dyes in classical domains of application, e.g. in textile dyeing and colour... 

Information concerning all aspects of the molecular structure and intermolecular interactions is encoded in the vibrational spectra. The art of vibrational spectroscopy can be defined as finding the optimum approach to extracting information from the spectra of molecules and to transform it into relevant answers to analytical questions, the most simple of which are what and how much There are three steps which should be optimized ... 

This is the maximum possible separation for two electron pairs. Once we have determined the optimum arrangement of the electron pairs around the central atom, we can specify the molecular structure of BeCl2—that is, the positions of the atoms. Since each electron pair on beryllium is shared with a chlorine atom, the molecule has a linear structure with a bond angle of 180 degrees ... 

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