Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Generalization concept

Of practical as well as theoretical interest, this book shows how general concepts can help solve specific organizational problems. [Pg.444]

In the preceding derivation, the repulsion between overlapping double layers has been described by an increase in the osmotic pressure between the two planes. A closely related but more general concept of the disjoining pressure was introduced by Deijaguin [30]. This is defined as the difference between the thermodynamic equilibrium state pressure applied to surfaces separated by a film and the pressure in the bulk phase with which the film is equilibrated (see section VI-5). [Pg.181]

The preceding sections were concerned with the description of molecular motion. An ambitious goal is to proceed further and influence molecular motion. This lofty goal has been at the centrepiece of quantum dynamics in the past decade and is still under intense investigation [182. 183. 184. 185. 186. 187. 188. 189. 190. 191. 192. 193 and 194]. Here we will only describe some general concepts and schemes. [Pg.2321]

Several studies have demonstrated the successful incoriDoration of [60]fullerene into polymeric stmctures by following two general concepts (i) in-chain addition, so called pearl necklace type polymers or (ii) on-chain addition pendant polymers. Pendant copolymers emerge predominantly from the controlled mono- and multiple functionalization of the fullerene core with different amine-, azide-, ethylene propylene terjDolymer, polystyrene, poly(oxyethylene) and poly(oxypropylene) precursors [63,64,65,66,62 and 66]. On the other hand, (-CggPd-) polymers of the pearl necklace type were fonned via the periodic linkage of [60]fullerene and Pd monomer units after their initial reaction with thep-xy y ene diradical [69,70 and 71]. [Pg.2416]

Representation of Molecular Structures by Electron Systems 2.6.2.1 General Concepts... [Pg.64]

This basic LFER approach has later been extended to the more general concept of fragmentation. Molecules are dissected into substructures and each substructure is seen to contribute a constant inaement to the free-energy based property. The promise of strict linearity does not hold true in most cases, so corrections have to be applied in the majority of methods based on a fragmentation approach. Correction terms are often related to long range interactions such as resonance or steric effects. [Pg.489]

For nearly half a century, Mendeleev s periodic table remained an empirical compilation of the relationship of the elements. Only after the first atomic model was developed by the physicists of the early twentieth century, which took form in Bohr s model, was it possible to reconcile the involved general concepts with the specificity of the chemical elements. Bohr indeed expanded Rutherford s model of the atom, which tried to connect the chemical specificity of the elements grouped in Mendeleev s table with the behavior of electrons spinning around the nucleus. Bohr hit upon the idea that Mendeleev s periodicity could... [Pg.31]

It is remarkable that chemists long resisted making the connection between boron and electron-deficient carbon, which, after all, are analogs. I was thus given the opportunity to be able to establish the general concept of five and six coordination of electron-deficient carbon and to open up the field of what I called hypercarbon chemistry. [Pg.156]

On the basis of my extensive study of stable, persistent carbocations, reported in more than 300 publications, I was able to develop the general concept of carbocations referred to in Chapter 9. Accordingly, in higher-coordinate (hypercoordinate) carbonium ions, of which pro-... [Pg.156]

This last identification makes the Q s strictly a matter of resonance, whereas the general concept of reactivity also includes steric effects. The effects... [Pg.445]

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. [Pg.254]

CLAIMS DIALOG, ORBIT Questel, STN IFI/Plenum Data Co. U.S. full bibliographic data abstract and full cl aim text chemical stmcture, general concept and patentee name coding... [Pg.48]

This article addresses the synthesis, properties, and appHcations of redox dopable electronically conducting polymers and presents an overview of the field, drawing on specific examples to illustrate general concepts. There have been a number of excellent review articles (1—13). Metal particle-filled polymers, where electrical conductivity is the result of percolation of conducting filler particles in an insulating matrix (14) and ionically conducting polymers, where charge-transport is the result of the motion of ions and is thus a problem of mass transport (15), are not discussed. [Pg.35]

The general concept of balances, as explained in detail in Appendix 1, can be applied to a recycle reactor. Figure 3.6.1 shows the possibilities for balance calculations in a recycle reactor. [Pg.71]

Occasionally a repair is needed that will maintain an aerodynamically smooth surface on exterior surfaces of sandwich structure. In this case an internal doubler is used to hold the filler detail (called a dime-dollar repair for obvious reasons Fig. 24). Damaged trailing edges can be the most difficult to repair because of the difficult geometry (Fig. 25). Repairs of larger areas follow the same general concepts but must be engineered individually to account for specific part shape and load requirements. [Pg.1170]

In the first environment, we are concerned with the potential health risks that chemicals pose to the public, as well as possible impacts on the ecology. In the latter case, we are concerned with indoor air quality and its possible adverse impacts on the health and safety of the workforce. In both cases the health dangers may be either acute, or long-term chronic health risks. We will first discuss general concepts of air pollution and table our discussions on... [Pg.9]

At this writing, the Interim Final guidance for the regulatory community with regard to interim measures is available (U.S. EPA, 1988). Based on this guidance, the general concepts for the application of interim measures can be identified. [Pg.114]

For the environmental consultant, an extensive overview of corrective action technologies is provided. Topics covered are the general concepts of corrective action programs, facility investigation principles, treatment technologies for wastes and waste streams, post treatment technologies and engineering considerations for corrective measures implementation. [Pg.320]

Conservation is a general concept widely used in chemical engineering systems analysis. Normally it relates to accounting for flows of heat, mass or momentum (mainly fluid flow) through control volumes within vessels and pipes. This leads to the formation of conservation equations, which, when coupled with the appropriate rate process (for heat, mass or momentum flux respectively), enables equipment (such as heat exchangers, absorbers and pipes etc.) to be sized and its performance in operation predicted. In analysing crystallization and other particulate systems, however, a further conservation equation is... [Pg.45]

PET fibers and filaments are characterized by a fibrillar superstructure that corresponds to the general concept of the fibrillar structure of synthetic fibers. The fibrillar... [Pg.839]

In a general concept of a symmetry-restricted anharmonic theory Krumhansl relates the phonon anomalies to the electron band topology. The latter is directly determined by the competition of nearest neighbour interactions which in turn can be a function of stress, composition and temperature Nagasawa, Yoshida Makita simulated the <110> ... [Pg.329]

Note in Figure 12-103A that the various operational sections of the functioning unit are indicated however, these sections may vary mechanically between the competing manufacturers, but the general concept is the same. [Pg.516]

Figure 23.9 illustrates the services required for a boiler. The individual items are covered separately in other sections and only the general concept is being considered here. [Pg.357]


See other pages where Generalization concept is mentioned: [Pg.137]    [Pg.784]    [Pg.2832]    [Pg.766]    [Pg.75]    [Pg.147]    [Pg.167]    [Pg.424]    [Pg.442]    [Pg.174]    [Pg.41]    [Pg.1494]    [Pg.1540]    [Pg.2347]    [Pg.488]    [Pg.215]    [Pg.263]    [Pg.468]    [Pg.4]    [Pg.4]    [Pg.171]    [Pg.324]    [Pg.249]    [Pg.150]    [Pg.657]   
See also in sourсe #XX -- [ Pg.6 ]




SEARCH



General Concepts

© 2024 chempedia.info