Dominance concept

Also precociously anticipating attitudes common later to the Dada artists, Pawlowski calls attention (in uppercase) to his dominating concept of LA RECHERCHE DE L ABSURDE. As he observes, THE QUEST... 

It is apparent from the above discussion that Le ChStelier s principle is the dominant concept behind most chemical reactions in the real world. It is particularly important in biochemical reactions, and external factors such as temperature can have a significant effect on biological equilibria. Catalysts (enzymes) are also key players in many biological and physiological reactions, as we shall see in Chapter 22. 

The authors added other empirical factors to the Guglielmi equation such as a mechanical factor that depended on convection forces, among other things. The cation adsorption model was the dominating concept for the description of co-deposition for several years thereafter. 

The minimization of chemical and physical interactions between polymer and blood plasma is presently the actual dominant concept to improve the blood compatibility of polymers for intra- and extracorporal short-term appUcations [104,105]. Most polymers for tube and catheter systems present a hydrophobic surface. Plasma technology is appUed to hydrophiUzation and graftcopolymeri-zation of hydrophihc monomers [106,107]. 

A number of different hypotheses have been proposed to account for the structure and consequent properties of nanocomposites, but the dominant concept relates to nanoparticle/matrix interactions. This topic is briefly reviewed below in connection with two issues nanoparticle dispersion the formation of stmcturally distinct interphase regions near nanoparticle surfaces. 

Subgroup Typical or dominant concept of the great group. Typic Kandihumult Coded as either the great group name with the typic prefix, or a combination of great group names. 

However, the finite rate of electrochemical processes itself is the dominating concept of electrochemical kinetics at present. This concept, developed and substantiated mainly by Academician A. N. Frumkin and his school, was found to be applicable to different kinds of electrode reactions, from simple recharging of ions to complex multistage processes[1]. 

This division is somewhat arbitrary siace it is really the pore size relative to the size of the sorbate molecule rather than the absolute pore size that governs the behavior. Nevertheless, the general concept is useful. In micropores (pores which are only slightly larger than the sorbate molecule) the molecule never escapes from the force field of the pore wall, even when ia the center of the pore. Such pores generally make a dominant contribution to the adsorptive capacity for molecules small enough to penetrate. Transport within these pores can be severely limited by steric effects, leading to molecular sieve behavior. 

An entirely new concept was iatroduced iato mbber technology with the idea of "castable" elastomers, ie, the use of Hquid, low molecular-weight polymers that could be linked together (chain-extended) and cross-linked iato mbbery networks. This was an appealing idea because it avoided the use of heavy machinery to masticate and mix a high viscosity mbber prior to mol ding and vulcanization. In this development three types of polymers have played a dominant role, ie, polyurethanes, polysulftdes, and thermoplastic elastomers. 

The dominant mechanism of purification for column ciystallization of sohd-solution systems is reciystallization. The rate of mass transfer resulting from reciystallization is related to the concentrations of the solid phase and free hquid which are in intimate contac t. A model based on height-of-transfer-unit (HTU) concepts representing the composition profQe in the purification sec tion for the high-melting component of a binaiy solid-solution system has been reported by Powers et al. (in Zief and Wilcox, op. cit., p. 363) for total-reflux operation. Typical data for the purification of a solid-solution system, azobenzene-stilbene, are shown in Fig. 22-10. The column ciystallizer was operated... 

The importance of these concepts can be illustrated by the extent to which the pyrolysis reactions contribute to gas produdion. In a moving-bed gasifier (e.g., producer-gas gasifier), the particle is heated through several distinct thermal zones. At the initial heat-up zone, coal carbonization or devolatilization dominates. In the successively hotter zones, char devolatihzation, char gasification, and fixed carbon... 

At high velocities where turbulence dominates, the main body of flowing fluid is well mixed in the direction normal to the flow, minor differences in temperature and concentration can be neglected, and the film concept can be applied. This describes the flow as if all gradients for temperature and concentration are in a narrow film along the interface with the solid (Nernst 1904), and inside the film conduction and diffusion are the transfer mechanisms. This film concept greatly simplifies the engineering calculation of heat and mass transfer. 

The concepts of electronegativity, hardness, and polarizability are all interrelated. For the kind of qualitative applications we will make in discussing reactivity, the concept that initial interactions between reacting molecules can be dominated by either partial electron transfer by bond formation (soft reactants) or by electrostatic interaction (hard reactants) is a useftxl generalization. 

From the 1960s onward, there was a greater interest in psychological issues, dominated by the concept of the human as a single-channel processor of information. This stimulated research into a number of areas. Studies of mental workload were concerned with the ability of humans to cope with extremely high levels of information in situations such as air traffic control. Vigilance studies, which focused on the human s role in situations with very low levels of stimulation such as radar monitoring, represented the other extreme of human performance that was considered. 

The atom and bond concepts dominate chemistry. Dalton postulated that atoms retained their identities even when in chemical combinations with other atoms. We know that their properties are sometimes transferable from one molecule to another for example, the incremental increase in the standard enthalpy of formation of a normal hydrocarbon per CHj group is —20.6 1.3 kJmol . We also know that more often there are subtle modifications to the electron density. 

On plant there is significant transport of corrosion product oxide ( crud ) from the feed and return lines. This can be the dominant factor, and overall the accumulation rate is effectively linear. It should be emphasised that corrosion of the type found in operating plant can only be reproduced in the laboratory by employing far higher concentrations (1 000 to 100000 times) than those existing in bulk solution in practice. Interpretations therefore invoke the concept of concentration mechanisms. 

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