Archetype

Sodium Chloride. Sodium chloride, a corrodent of many materials, is the archetype contaminant and has been studied more than other salts. The solubiUty of sodium chloride in superheated steam is shown at the conditions of a typical steam turbine expansion in Figure 14. The solubiUties were measured in the region of higher solubiUty (9). As the steam expands, sodium chloride becomes considerably less soluble. The solubiUty, S, in parts per biUion (ppb) can be represented by equation 3 ... 

Alloys and blends are of great commercial significance. The archetype of "alloys" is the poly(phenylene oxide)—polystyrene resin discussed eadier. Important examples of blends based on immiscible resins are afforded by the polycarbonate—poly(butylene terephthalate) resins and polycarbonate—ABS blends. 

The archetype of the ionic ceramic is sodium chloride ("rocksalt"), NaCl, shown in Fig. 16.1(a). Each sodium atom loses an electron to a chlorine atom it is the electrostatic attraction between the Na ions and the CF ions that holds the crystal together. To achieve the maximum electrostatic interaction, each Na has 6 CF neighbours and no Na neighbours (and vice versa) there is no way of arranging single-charged ions that does better than this. So most of the simple ionic ceramics with the formula AB have the rocksalt structure. 

DJ Wales, MA Miller, TR Walsh. Archetypal energy landscapes. Nature 394 758-760, 1998. 

Fullerenes are a range of stable closed-shell carbon molecules and their derivatives, of which Qo is the archetype. The next highest stable member of the series is C70 which is found in small quantities with in arc electrode soot. C,o may be regarded as a Qo molecule with an extra belt of hexagons inserted at the... 

The migration of one atomic species in another, in the solid state, is the archetype of a materials-science parepisteme. From small beginnings, just over a century ago, the topic has become central to many aspeets of solid-state science, with a huge dedicated literature of its own and specialised conferences attended by several hundred participants. 

Silicon is today the most studied of all materials, with probably a larger accumulated number of scientific papers devoted to its properties than for any other substance. It is the archetype of a semiconductor and everybody knows about its transcendent importance in modern technology. 

As materials chemistry has developed, it has come to pay more and more attention to that archetypal concern of materials scientists, microstructure. That concern came in early when the defects inherent in non-stoichiometric oxides were studied by the Australian. I.S. Anderson and others (an early treatment was in a book edited by Rabenau 1970), but has become more pronounced recently in the rapidly growing emphasis on self-assembly of molecules or colloidal particles. This has not yet featured much in books on materials chemistry, but an excellent recent popular account of the broad field has a great deal to say on self-assembly (Ball 1997). The phenomenon of graphoepitaxy outlined in Section 10.5.1.1 is a minor example of what is meant by self-assembly. 

Fig. 11. The sealed lip of a PCNT heat treated at 2800°C with a toroidal structure (T) and, (b) molecular graphics images of archetypal flattened toroidal model at different orientations and the corresponding simulated TEM images.

Fig. 3. Molecular graphics images of an archetypal flattened toroidal model of a nanotube with n = 5 and m = 4al three different orientations in a plane perpendicular to the paper. Note the points on the rim where...

During the course of the study on the simplest archetypal twin-walled structures in PCNT material described here, the observation of lijima et al.[5 on related multi-walled hemi-toroidal structures in ACNTs appeared. It will be most interesting to probe the differences in the formation process involved. 

The strong shock regime is the classic archetype and is characterized by a single narrow shock front that carries the material from its initial condition into a new high pressure, elevated temperature, high kinetic energy state. Following a quiescent period at peak pressure, whose duration depends upon... 

Perikinetic motion of small particles (known as colloids ) in a liquid is easily observed under the optical microscope or in a shaft of sunlight through a dusty room - the particles moving in a somewhat jerky and chaotic manner known as the random walk caused by particle bombardment by the fluid molecules reflecting their thermal energy. Einstein propounded the essential physics of perikinetic or Brownian motion (Furth, 1956). Brownian motion is stochastic in the sense that any earlier movements do not affect each successive displacement. This is thus a type of Markov process and the trajectory is an archetypal fractal object of dimension 2 (Mandlebroot, 1982). 

The ability of C to catenate (i.e. to form bonds to itself in compounds) is nowhere better illustrated than in the compounds it forms with H. Hydrocarbons occur in great variety in petroleum deposits and elsewhere, and form various homologous series in which the C atoms are linked into chains, branched chains and rings. The study of these compounds and their derivatives forms the subject of organic chemistry and is fully discussed in the many textbooks and treatises on that subject. The matter is further considered on p. 374 in relation to the much smaller ability of other Group 14 elements to form such catenated compounds. Methane, CH4, is the archetype of tetrahedral coordination in molecular compounds some of its properties are listed in Table 8.4 where they are compared with those of the... 

Thomas Alva Edison, is the archetype of American ingenuity and inventiveness. He played a critical role in the early commercialization of electric power. He designed the first commercial incandescent electric light and power system and his laboratory produced... 

Human labor dominated all subsistence foraging activities, as the food acquired by gathering and hunting sufficed merely to maintain the essential metabolic functions and to support veiy slow population growth. Societies not very different from this ancestral archetype survived in some parts of the world (South Africa, Australia) well into the twentieth century Because they commanded veiy little energy beyond their subsistence food needs, they had very few material possessions and no permanent abodes. 

This limitation was already painfully obvious to the organic chemists in the 1880s these are statie struetures, whereas of eourse any moleeule at any temperature is a jelly-like pulsating, librating and vibrating entity. Only a terribly simplistic eye would see a molecule frozen into this Platonic archetype of the structural formula. 

Peptoids are an archetypal and relatively conservative example of a peptidomimetic oligomer (Tab. 1.1). In fact, the sequence of atoms along the peptoid backbone is identical to that of peptides. However, peptoids differ from peptides in the marmer of side chain appendage. Specifically, the side chains of peptoid oligo-... 

Khunrath s engraving of Christ-Anthropos, the Archetype of the universe (fig. 3), initiated many of the elements later found in Fludd s prolific illustrations of the Macrocosmic Man. These included the use of the male nude, kabbalistic inscriptions, geographical compass-points, the diagrammatic structure of the Macrocosm and the motif of the dove of the Holy Spirit. The apocalyptic context of these images and their role in the Protestant Reformation of the late sixteenth and early seventeenth centuries will be considered in the following chapter. 

We propose that the tomato fruit B subunit is the archetypal member of a new class of plant cell wall proteins, which we have named AroGPs, for Aromatic Amino Acid Rich GlycoProteins. AroGPs have the following characteristics ... 

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