Cavity effect

We have already encountered the ir, a, and p quantities. The 8h term is inserted to account for the cavity effect. Equation (8-80) is a 12-parameter equation for which considerable generality is claimed, in that it is said to be applicable to chemical rates and equilibria, spectra, solubilities, partition coefficients, and even biological responses. Usually, of course, by judicious selection of solvents, it is possible to reduce the number of parameters by ensuring that some terms are negligible.An example requiring most of the parameters in Eq. (8-80) is the solvolysis/dehydrohalogenation of r-butyl chloride in 21 HBD and non-HBD solvents, for which this correlation was found ... 

CAVj p arising from the dielectric cavity effect, and... 

Here, however, it is possible to obtain stabilization of the low-dense lattice build-up of bulky molecules via intermolecular adhesion and orientation forces. Molecules with planar structural elements are advantageous in this respect since they are apt to support the lattice aggregate, and at the same time they are able to partition off cavities effectively. It is very convenient to use aromatic units. 

As noted previously, rate accelerations imposed by the cycloamyloses may be competitively inhibited by the addition of inert reagents to the reaction medium. The inhibitor, by competing with the substrate for the cycloamylose cavity, effectively removes a fraction of the catalyst from the reaction coordinate. This observation lends additional force to the mechanism illustrated in scheme I. 

Die Wirkung von Hohlladungen wird in den USA als Munroe-Effekt bezeichnet, da Munroe diese Erscheinung 1888 beschrieben hat. Gelegentlich findet man auch Bezeichnungen wie cavity effect 1, lined cavity effect" - Hohlladungen). 

In this respect, the solvatochromic approach developed by Kamlet, Taft and coworkers38 which defines four parameters n. a, ji and <5 (with the addition of others when the need arose), to evaluate the different solvent effects, was highly successful in describing the solvent effects on the rates of reactions, as well as in NMR chemical shifts, IR, UV and fluorescence spectra, sol vent-water partition coefficients etc.38. In addition to the polarity/polarizability of the solvent, measured by the solvatochromic parameter ir, the aptitude to donate a hydrogen atom to form a hydrogen bond, measured by a, or its tendency to provide a pair of electrons to such a bond, /, and the cavity effect (or Hildebrand solubility parameter), S, are integrated in a multi-parametric equation to rationalize the solvent effects. 

Detonation, Lined Cavity Effect. See under DETONATION, MUNROE-NEUMANN EFFECT... 

DETONATION, MUNROE-NEUMANN EFFECT (OR SHAPED CHARGE EFFECT) AND LINED-CAVITY EFFECT IN. (Called also Munroe Effect, Neumann Effect, Cavity Effect, ... 

Accdg to Cook (Ref 55, p 226) it is quite likely that the advantage of using lined cavity charges was recognized in Amer mining industry much earlier than 1936, the year in which Dr R.W. Wood is attributed by Eichelberger (Ref 4la) the discovery of the lined-cavity effect... 

In a similar historical description given by Cook, it is stated that Mohaupt was a "Swiss inventor who, in exploiting his patent, participated in early developments of the lined-cavity effect in America in the early part of WWIl"... 

Following WWII, important contributions to the cavity effect were made in addition to the work at CIT and BRL, which continued the flash radiographic studies among other important investigations, by the following laboratories NOL (Naval Ordnance... 

Studies were made of the detonation with hemispherical, ellipsoidal, and conical liners and a theory was developed which appeared to give a plausible explanation of the optimum shapes of liners. It was discovered during these studies, that highspeed rotation decreased very markedly the cavity effect, and that consequently, spin-stabilized projectiles were ill-adapted to cavity charges. Towards the end of 1943, the spreading of the jet, due to rotation, was confirmed photographically by the Kerr-cell camera... 

Cook (Ref 55, p 227) and Andreev Belyaev (Ref 58, p 482) showed figs comparing flat end effect of a charge (a), versus Munroe-Neumann effect or unlined cavity effect (b), versus lined cavity effect (c)... 

Birkhoff et al (Ref 28) gave a fairly complete mathematical theory of cavity-effect phenomenon together with experimental data that aided the formulation and testing of the theory. They based the theory upon the classical thermodynamics of perfect fluids. It is applicable because the strength of metals used for linings can be neglected at the high pressures encountered... 

The above description of Munroe-Neumann effect and of lined cavity effect must be considered as an introduction to the subject and some of the material may be obsolete. The description cannot be brought up-to-date because nearly all American and British military information of the last decade is classified... 

Shaped charge for perforating oil well casing) 55) Cook (1958), Chapter 10, "Principles of Shaped Charges , which includes History (pp 226-28) Explosive factors in cavity effect (228-29) Application to mass loading in different geometries (229-35) Detonation pressure in nonideal explosives (235-44) Mechanism of linear collapse and jet formation (244-47) Metal-... 

Charge Effect. See under MUNROE-NEUMANN EFFECT AND LINED-CAVITY EFFECT... 

Jet Formation in Shaped Charges. See Detonation BMT (Birkhoff-MacDougall-Pugh-Taylor) Theory of Jet Formation in Shaped Charges in Vol 4 of Encycl, p D226-R and Detonation, Munroe-Neumann Effect (or Shaped. Charge Effect) and Lined-Cavity Effect in on pp D442-Rff... 

Lined Cavities of Explosives (Lined Cavity Effect). See under Detonation, Munroe-Neumann Effect (or Shaped Charge Effect) And Lined-Cavity Effect In, Encycl 4 (1969), D444-R to D450-R... 

Finally the minimum observed for the AG°t function of n-Bu4NBr in both chemical systems may be interpreted as follows the variation of AG°t(+) and AG°t(-) with solvent composition are generally not linear, so the minimum can be looked upon as the consequence of the opposite behavior of anion and cation towards the solvent molecules. However this interpretation does not take into account the fact that at low organic solvent mole fraction one has AH°t < T AS°t. This observation means that a structural (nonspecific) effect predominates in the water-rich region. This effect might be related to the cavity effect as can be evaluated from Pierrotti s scaled particle theory because the large size of the... 

Detonation, Munroe-Neumann effect and lined cavity effect in 4 D442... 

Surface Pressure, Potential, and Fluidity Characteristics for Various Interactions in Mixed Monolayers. It is possible to distinguish various types of interactions which occur in mixed monolayers by measuring the surface pressure, surface potential, and surface fluidity of the monolayers. Deviation from the additivity rule of molecular areas indicates either an interaction between components or the intermolecular cavity effect in mixed monolayers. 

Intermolecular Cavity Effect. Figure 5a shows the general characteristics of mixed monolayers in which the "intermolecular cavity effect ... 

Hydrocarbon-Hydrocarbon Interaction. Figure 5c shows the general characteristics of mixed monolayers in which hydrocarbon-hydrocarbon interaction occurs—e.g., trimyristin-myristic acid monolayers (16). The average area per molecule shows a deviation, whereas the surface potential per molecule follows the additivity rule. Hydrocarbon-hydrocarbon interaction also increases the cohesive force in the lipid layer and therefore reduces the fluidity of the mixed monolayer. It is evident from Figures 3a and 3c that surface fluidity is the only parameter which distinguishes an intermolecular cavity effect from hydrocarbon-hydrocarbon interaction. 

Cavity Effect, Same as Munroe-Neumann Effect, Shaped Charge Effect or Hollow Charge Effect... 

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