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Demarcation

Demarcation is the marking off and separating of various areas used for different functions that helps to bring order into a work area by separating work activities, storage activities, passage, and roadways. [Pg.138]


A cyUndrical or, preferably, a pear-shaped separatory funnel (Fig. II, 1, 5, e and d) of 10-15 ml. capacity is usually employed for the separation of immiscible liquids. For separations on a smaller scale, a dropper pipette may be used the upper layer is best removed with a bent pipette as in Fig. XII, 1,3. For liquids which tend to emulsify, centrifugation (a hand centrifuge is satisfactory) will usually produce a clean line of demarcation between two immiscible liquids. [Pg.1102]

In discussions of the surface properties of solids having a large specific surface, it is convenient to distinguish between the external and the internal surface. The walls of pores such as those denoted by heavy lines in Fig. 1.8 and 1.11 clearly comprise an internal surface and equally obviously the surface indicated by lightly drawn lines is external in nature. In many cases, however, the distinction is not so clear, for the surfaces of the primary particles themselves suffer from imperfections in the forms of cracks and fissures those that penetrate deeply into the interior will contribute to the internal surface, whereas the superficial cracks and indentations will make up part of the external surface. The line of demarcation between the two kinds of surface necessarily has to be drawn in an arbitrary way, but the external surface may perhaps be taken to include all the prominences and all of those cracks which are wider than they are deep.,The internal surface will... [Pg.23]

The following sections contain a review of many of the varied synthetic systems that have been developed to date utilising noncovalent interactions to form assembhes of molecules. These sections are loosely demarcated according to the most important type of noncovalent interactions utilized in conferring supramolecular order (ie, van der Waal s interactions, electrostatic interactions, and hydrogen bonds). For extensive reviews, see References 1,2,4—6,22,46,49,110—112. Finally, the development of self-assembling, self-replicating synthetic systems is noted. [Pg.208]

Fig. 3. Vapor—liquid-phase diagram for the HCl—H2 O system (5) where (-) represents the demarcation between the two-phase region and the gas... Fig. 3. Vapor—liquid-phase diagram for the HCl—H2 O system (5) where (-) represents the demarcation between the two-phase region and the gas...
Fig. 2. Schematic stress—strain diagram, where UTS = ultimate tensile stress and (-------------) represents the demarcation between elastic and plastic behavior. Fig. 2. Schematic stress—strain diagram, where UTS = ultimate tensile stress and (-------------) represents the demarcation between elastic and plastic behavior.
These demarcations are arbitrary and the boundaries are usually not clear cut. [Pg.32]

Refractories are materials that resist the action of hot environments by containing heat energy and hot or molten materials (1). There is no weU-estabhshed line of demarcation between those materials that are and those that are not refractory. The abiUty to withstand temperatures above 1100°C without softening has, however, been cited as a practical requirement of industrial refractory materials (see Ceramics). The type of refractories used in any particular apphcation depends on the critical requirements of the process. For example, processes that demand resistance to gaseous orHquid corrosion require low permeabihty, high physical strength, and abrasion resistance. Conditions that demand low thermal conductivity may require entirely different refractories. Combinations of several refractories are generally employed. [Pg.22]

The result is a hard, abrasion-resistant surface, important in many appHcations of cast kon. The depth of the chill may be controlled by regulating the amount of tellurium added. The casting shows a sharp demarcation line between the chilled and unchilled regions there is no intermediate or motded zone. Yet, the chilled portion shows excellent resistance to spalling from thermal or mechanical shock. Tellurium-treated kon is more resistant to sulfuric and hydrochloric acids than is untreated, unchilled gray kon. The amount added ranges from 0.005 to 0.1% ca 60% is lost by volatilization. Excessive addition causes porosity in the castings. [Pg.391]

The demarcation between the compounds of Section 5.05.5.2 and those of Section... [Pg.119]

Labor productivity is very much dependent on the health and well-being of the workers and also on the availability of laborsaving tools and construction equipment. The frequency of strikes, hohdays, slowdowns, and pohtical unrest will also depress productivity. Closed-shop practices or demarcation disputes will also affect the productivity of labor. The use of standard equipment, parts, and methods tends to improve productivity. [Pg.876]

There is no definite demarcation line, but positive displacement pumps normally arc preferred (wer centrifugal pumps in applications of ... [Pg.53]

Hence if a laboratory measurement at 25°C yields a conductivity of 100 pS/m the same liquid at -10°C will have a conductivity of about 30 pS/m. The effects of low temperature combined with the elevated dielectric constants of many nonconductive chemicals support use of the 100 pS/m demarcation for nonconductive liquids (5-2.5) rather than the 50 pS/m demarcation used since the 1950s by the petroleum industry. For most hydrocarbons used as fuels, the dielectric constant is roughly 2 and a demarcation of 50 pS/m is adequate, provided the conductivity is determined at the lowest probable handling temperature. [Pg.64]

Since conductivity is highly sensitive to sample purity and temperature, group demarcations can be given only to within an order of magnitude. It should always be considered that conductivity under practical conditions... [Pg.101]

Owing to the change from exponential to hyperbolic relaxation, a nominal dissipation time of 100 s is assigned in Appendix B to all liquids whose conductivities are below 2 pS/m. The 2 pS/m demarcation is convenient... [Pg.212]

Ground should be impervious, and sloped and drained, with demarcation lines. [Pg.403]

Once it is recognized that particles adhere to a substrate so strongly that cohesive fracture often results upon application of a detachment force and that the contact region is better describable as an interphase [ 18J rather than a sharp demarcation or interface, the concept of treating a particle as an entity that is totally distinct from the substrate vanishes. Rather, one begins to see the substrate-particle structure somewhat as a composite material. To paraphrase this concept, one could, in many instances, treat surface roughness (a.k.a. asperities) as particles appended to the surface of a substrate. These asperities control the adhesion between two macroscopic bodies. [Pg.143]

It is somewhat disconcerting that the MYD analysis seems to present a sharp transition between the JKR and DMT regimes. Specifieally, in light of the vastly different response predicted by these two theories, one must ponder if there would be a sharp demarcation around /x = 1. This topic was recently explored by Maugis and Gauthier-Manuel [46-48]. Basing their analysis on the Dugdale fracture mechanics model [49], they concluded that the JKR-DMT transition is smooth and continuous. [Pg.153]

To examine sedimentation in greater detail, let us examine the events occurring in a small-scale experiment conducted batchwise, as illustrated in Figure 9. Particles in a narrow size range will settle with about the same velocity. When this occurs, a demarcation line is observed between the supernatant clear liquid (zone A) and... [Pg.282]

Many thermoplastics are now accepted as engineering materials and some are distinguished by the loose description engineering plastics. The term probably originated as a classiflcation distinguishing those that could be substituted satisfactorily for metals such as aluminium in small devices and structures from those with inadequate mechanical properties. This demarcation is clearly artificial because the properties on which it is based are very sensitive to the ambient temperature, so that a thermoplastic might be a satisfactory substitute for a metal at a particular temperature and an unsatisfactory substitute at a different one. [Pg.6]

Forty-hour training was required for personnel entering the exclusion zone, and additional supervisory training was required for site supervisors. Site control procedures described in the Site C contractor s SSAHP included maintenance of site control logs at each access point, use of red tape or chainlink fencing to demarcate hot zones, and use of the buddy system in all exclusion and contamination reduction zone areas. Site communications relied almost exclusively on visual sighting of employees the plan did not describe the use of two-way radios. This suggested that all employees in hot zones can be observed continuously from the support zones. [Pg.198]

The primary contractor at Site A had identified clean zones, buffer zones, and related site control procedures in its written plan however, onsite implementation differed from those specified in the plan. For example, the exclusion zones identified in the plan at the upper pad of the wastewater treatment plant, the dredge area, and the solid waste storage area were marked with signs requiring PPE, but were not labeled with red banners as called for in the plan. In addition, the exclusion zones did not have controlled access through one point of entry as described in the plan, nor were the buffer zones established and demarcated with yellow banners. [Pg.200]

Event trees and fault trees work together to model plant accidents, but the demarcation be tween them is the choice of the analysts. This has resulted in two styles 1) small event tree-large fault tree (SELF), and 2) large event tree-small fault tree (LESF). SELF is the style used in WASH-1400, in NRC sponsored PSAs, and in several utility PSAs. LESF was introduced by PL G in the Oyster Creek PSA and used subsequently by PL G and several utilities,... [Pg.113]

A characteristic feature of the action of the opium alkaloids is their simultaneous depressing and exciting action on the central nervous system. In this respect there is no clear line of demarcation between the morphine group—morphine, codeine and thebaine—and the papaverine-narcotine group, and as the series is ascended in the order, morphine, papaverine, codeine, narcotine, thebaine, narcotic action diminishes and power of rellex stimulation increases until in thebaine a strychnine-like effect is exhibited. [Pg.259]

Equipment boundary Demarcation of the equipment showing components included and interfaces with excluded piping, electrical and instrumentation systems. Numbers shown on electrical equipment are taken from American Standard Device Function Numbers. [Pg.136]


See other pages where Demarcation is mentioned: [Pg.106]    [Pg.60]    [Pg.83]    [Pg.436]    [Pg.373]    [Pg.440]    [Pg.403]    [Pg.436]    [Pg.33]    [Pg.441]    [Pg.412]    [Pg.3]    [Pg.446]    [Pg.450]    [Pg.532]    [Pg.1295]    [Pg.255]    [Pg.16]    [Pg.83]    [Pg.181]    [Pg.183]    [Pg.475]    [Pg.283]    [Pg.33]    [Pg.121]   
See also in sourсe #XX -- [ Pg.44 ]




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