Principle of locality

Posokhin, V. N., and A. M. Zhivov. 1997. Principles of local exhaust design. In Proceedings of the 5th International Symposium on Ventilation for Contaminant Control, vol. 1. C.anadian Environment Industry Association, Ottawa. 

The advantages of low-level hoods are listed in Table 13.17. The first step is to verify that the general principle of local capture of emissions is acceptable and feasible for the process. The next step is to establish the most efficient hood geometry. In most cases, this involves a balancing of the degree of process interference tolerable against the degree of emission source enclosure required. 

There are three different approaches to a thermodynamic theory of continuum that can be distinguished. These approaches differ from each other by the fundamental postulates on which the theory is based. All of them are characterized by the same fundamental requirement that the results should be obtained without having recourse to statistical or kinetic theories. None of these approaches is concerned with the atomic structure of the material. Therefore, they represent a pure phenomenological approach. The principal postulates of the first approach, usually called the classical thermodynamics of irreversible processes, are documented. The principle of local state is assumed to be valid. The equation of entropy balance is assumed to involve a term expressing the entropy production which can be represented as a sum of products of fluxes and forces. This term is zero for a state of equilibrium and positive for an irreversible process. The fluxes are function of forces, not necessarily linear. However, the reciprocity relations concern only coefficients of the linear terms of the series expansions. Using methods of this approach, a thermodynamic description of elastic, rheologic and plastic materials was obtained. 

The third approach is called the thermodynamic theory of passive systems. It is based on the following postulates (1) The introduction of the notion of entropy is avoided for nonequilibrium states and the principle of local state is not assumed, (2) The inequality is replaced by an inequality expressing the fundamental property of passivity. This inequality follows from the second law of thermodynamics and the condition of thermodynamic stability. Further the inequality is known to have sense only for states of equilibrium, (3) The temperature is assumed to exist for non-equilibrium states, (4) As a consequence of the fundamental inequality the class of processes under consideration is limited to processes in which deviations from the equilibrium conditions are small. This enables full linearization of the constitutive equations. An important feature of this approach is the clear physical interpretation of all the quantities introduced. 

When a two- or higher-phase system is used with two or more phases permeable to the solute of interest and when interactions between the phases is possible, it would be necessary to apply the principle of local mass equilibrium [427] in order to derive a single effective diffusion coefficient that will be used in a one-equation model for the transport. Extensive justification of the principle of local thermdl equilibrium has been presented by Whitaker [425,432]. If the transport is in series rather than in parallel, assuming local equilibrium with equilibrium partition coefficients equal to unity, the effective diffusion coefficient is... 

Whitaker, S, Improved Constraints for the Principle of Local Thermal Equilibrium, Industrial and Engineering Chemistry Research 29, 983, 1991. 

Pauling s principle of local electrical neutrality Charges are neutralized locally in crystals. Lewis s principle of zero formal charges Charges are neutralized locally in molecules. 

Equations (A.23) and (A.25) pertain to equilibrium conditions of homogeneous systems. Such systems have constant properties over space and time and there is no entropy production. We shall now be interested in systems, away from equilibrium where properties vary as functions of location as well as time. Tb apply the results of thermodynamics to nonequilibrium systems., the principle of local (microscopic) equilibrium is invoked. For that reason it is useful to work with the thermodynamic variables on a unit volume basis. Equation (A.25) then becomes... 

In summary, the principle of local invariance in a curved Riemannian manifold leads to the appearance of compensating fields. The electromagnetic field is the compensating field of local phase transformation and the gravitational field is the compensating field of local Lorentz transformations. 

Figure 6-1 Generalized molecular structure of a local anesthetic, consisting of a hydrophobic aromatic residue, the linkage site, an intermediate alkyl chain, and a hydrophilic amino group. (Adapted from Lesher GA. General principles of local anesthetics. In Onofrey BE, ed. Clinical optometric pharmacology and therapeutics. Philadelphia JB Lippincott, 1991 Chapter 53.)...

For the simpler case of molecule pair interactions, such as the interactions between two reactants, local shape complementarity is of importance. The basic principle of local shape similarity measures is also applicable for the construction of local shape complementarity measures. 

Principle of local symmetry. In the interaction between a symmetric or a quasisymmetric monomer and its own active center being in the free-radical or free-ionic state, a cyclic adduct of the donor-acceptor type exhibiting the local pseudosymmetry of the third order is formed as one of the intermediates. 

Among all five postulates formulated in this work, the principle of local symmetry is of the most polymerization character. The validity of its introduction is based on intuition, the complex of experimental data on the investigation... 

Let us assume that the polymerization of quasisymmetric dienes proceeds in accordance with the principle of local symmetry, Le., via the stage of formation of a locally symmetric intermediate. The structure of the locally symmetric diene intermediate (Scheme 11) is tentative. However, this is not very important since the train of thoughts is based only on the hypothesis of the existence of the Jahn-Teller effect in this case. 

Let us assume that we are dealing with an alternating copolymerization of butadiene (or isoprene) with a monomer drastically differing from butadiene. In this case the symmetric diene will be attached all the time to an alien radical active center and, vice versa, an alien monomer will be bonded to a diene radical center. The principle of local symmetry is no longer valid, and in the absence of the Jahn-Teller effect the formation of only the 1,4 (4,l)-structuie of diene units in the copolymer should be expected. 

In this case, since the principle of local symmetry is weakened, it should be expected that the content of vinyl structure in polydiene is lower than in polybutadiene. In fact, e.g., in polychloroprene, the fraction of vinyl units in the temperature range from — 40 to + 40 °C varies from 1 to 3% [49]. 

Central to the EPR paradox is a thought experiment in which two spins are initially coupled to a state with S = 0 and are then separated to a large distance, at which they can be separately observed. Quantum mechanics appMently predicts that the two spins remain forever coupled, but this conflicts with Einstein s principle of locality or separability , according to which spatially well separated systems must be independent, no matter how strongly they have interacted in the past. It is now widely held that Einstein was wrong and that non-locality follows inevitably from quantum mechanics i.e. that even distant systems are never truly separable. 

It is the non-zero value of the integral in (31), irrespective of the separation of A and B, that violates any principle of locality it appears as a direct result of applying standard quantum mechanics and seems to imply some kind of action at a distance that keeps the two spins coupled. It should be noted, however, that the postulate of Bohm and Bell - that the sytem is disintegrated by some kind of process that... 

A new qualitative quantum-chemical concept of the etementary act ct addition pdymerizatioa has been proposed as the development ct the polymerization theory. An extensive set of various data on the kinetics and the mechanism of polymer structure controlling has been found to have a new explanation from an uniform viewpoint. This concept is devdoped in the framework of the aximnatic approach to the general polymerization theory and is based on five postulates, namely the principle of the intermediate, the principle ct intermediate cyclicity, the principle of correspondence, the principle of local symmetry and the spin exclusion principle. 

In the case of ISE of electrolytes, one has to take into consideration that in aqueous solutions strong electrolytes dissociate into constituent ions. If only one electrolyte is present in the sample, the cations and anions are forced to move together, even in the case that there is no tendency to form ionic pairs. In this marmer the principle of local electroneutrality is abided by. Obviously, the larger ion that happens to be excluded from the porous space will govern to a greater extent the velocity of the salt zone migration in the column and the final elution volume. The smaller counter ion will probably not retard the zone to a noticeable extent. 

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