PREVAIL

The virial equation is appropriate for describing deviations from ideality in those systems where moderate attractive forces yield fugacity coefficients not far removed from unity. The systems shown in Figures 2, 3, and 4 are of this type. However, in systems containing carboxylic acids, there prevails an entirely different physical situation since two acid molecules tend to form a pair of stable hydrogen bonds, large negative... 

Of course, some processes do not require a reactor, e.g., some oil refinery processes. Here, the design starts with the sepauration system and moves outward to the heat exchanger network and utilities. However, the basic hierarchy prevails. 

Chlorides of sodium, magnesium and calcium are almost always the prevailing compounds, along with gypsum and calcium carbonate. 

The chemistry of cement slurries is complex. Additives will be used to ensure the slurry remains pumpable long enough at the prevailing downhole pressures and temperatures but sets (hardens) quickly enough to avoid unnecessary delays in the drilling of the next hole section. The cement also has to attain sufficient compressive strength to withstand the forces exerted by the formation over time. A spacer fluid is often pumped ahead of the slurry to clean the borehole of mudcake and thereby achieve a better cement bond between formation and cement. 

Although a single project manager may direct activities throughout a project life, he or she will normally be supported by a project team whose oomposition should reflect the type of project and the experience levels of both company and contractor personnel. The make up and size of the team may change over the life of a project to match the prevailing activity levels in each particular section of the project. 

Royalty is normally charged as a percentage of the gross revenues from the sale of hydrocarbons, and may be paid in cash or in kind (e.g. oil). The prevailing oil price is used. 

It is possible to expect that the endurance at the fixed loading allows to exclude the component AEl, because the development of prevailing defect is continuing, and numerous initiation of stable micro-cracks outside the zone are excepted. 

The test with the step loading shows that acoustic activity of the solid adhesive joints in the tested carbon plastic is quite low. The maximum on the endurance area was fixed at the predestructive moment. The last is evidence to the fact that the prevailing defect of the adhesive joints is starting its development at the loading level, which is close to the destruction point. 

Each graphic printout is examined by the analyst according to rules defined in the applicable procedures. The human diagnostic always prevails over the computer. 

The gaseous tracer method yields the equivalent piston flow linear velocity of the gas flow in the pipe without any constraints regarding flow regime under the conditions prevailing for flare gas flow. 

Here, the distances x and a are relative to planes A and B located far enough from the surface region so that bulk phase properties prevail. The actual amount of component i present in the region between A and B will be... 

This chapter on adsorption from solution is intended to develop the more straightforward and important aspects of adsorption phenomena that prevail when a solvent is present. The general subject has a vast literature, and it is necessary to limit e presentation to the essential features and theory. 

At low solvent density, where isolated binary collisions prevail, the radial distribution fiinction g(r) is simply related to the pair potential u(r) via g ir) = exp[-n(r)//r7]. Correspondingly, at higher density one defines a fiinction w r) = -kT a[g r). It can be shown that the gradient of this fiinction is equivalent to the mean force between two particles obtamed by holding them at fixed distance r and averaging over the remaining N -2 particles of the system. Hence w r) is called the potential of mean force. Choosing the low-density system as a reference state one has the relation... 

The nonlinear response of an individual molecule depends on die orientation of the molecule with respect to the polarization of the applied and detected electric fields. The same situation prevails for an ensemble of molecules at an interface. It follows that we may gamer infonnation about molecular orientation at surfaces and interfaces by appropriate measurements of the polarization dependence of the nonlinear response, taken together with a model for the nonlinear response of the relevant molecule in a standard orientation. 

Small molecules in low viscosity solutions have, typically, rotational correlation times of a few tens of picoseconds, which means that the extreme narrowing conditions usually prevail. As a consequence, the interpretation of certain relaxation parameters, such as carbon-13 and NOE for proton-bearing carbons, is very simple. Basically, tlie DCC for a directly bonded CH pair can be assumed to be known and the experiments yield a value of the correlation time, t. One interesting application of the measurement of is to follow its variation with the site in the molecule (motional anisotropy), with temperature (the correlation... 

We make one important note here regarding nomenclature. Early explanations of CIDNP invoked an Overhauser-type mechanism, implying a dynamic process similar to spin relaxation hence the word dynamic m the CIDNP acronym. This is now known to be incorrect, but the acronym has prevailed in its infant fomi. 

Figure C2.18.3. Relationship between ion-assisted etching and directionality in plasma etching, (a) Demonstration of the synergy between ion bombardment and reactive species during ion-assisted etching, (b) Ions incident on an etched feature. This situation prevails in glow discharges when the feature dimensions are much less than the plasma sheath thickness. Reproduced from [35]...

With my European background, I was when I came to America and still am impressed by the rather loosely organized, more decentralized way of research support. Of course, even in a great country like ours resources are not limitless and inevitably prevailing trends of research set priorities. In my field of interest the 1970s and 1980s were a period when, after two oil crises, research on hydrocarbon fuels and their synthetic preparation had significant public interest and support. Catalytic research in its many aspects was heavily pursued and considered a national priority. 

The introduction of additional alkyl groups mostly involves the formation of a bond between a carbanion and a carbon attached to a suitable leaving group. S,.,2-reactions prevail, although radical mechanisms are also possible, especially if organometallic compounds are involved. Since many carbanions and radicals are easily oxidized by oxygen, working under inert gas is advised, until it has been shown for each specific reaction that air has no harmful effect on yields. 

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