Degree disorder

All data are for the pseudocells and compositions staled. The true cells have doubled values of b and can be in varying degrees disordered a and c must often be differently defined. The structure of C-S-H(I) has little more than two-dimensional order, and that of C-S H(II) has less than full three-dimensional order. 

The treatment of such order-disorder phenomena was initiated by Gorsky (1928) and generalized by Bragg and Williams (1934) [5], For simplicity we restrict the discussion to the synnnetrical situation where there are equal amounts of each component (x = 1/2). The lattice is divided into two superlattices a and p, like those in the figure, and a degree of order s is defined such that the mole fraction of component B on superlattice p is (1 +. s)/4 while that on superlattice a is (1 -. s)/4. Conservation conditions then yield the mole fraction of A on the two superlattices... 

The label liquid crystal seems to be a contradiction in tenns since a crystal cannot be liquid. However, tire tenn refers to a phase fonned between a crystal and a liquid, witli a degree of order intennediate between tire molecular disorder of a liquid and tire regular stmcture of a crystal. Wlrat we mean by order here needs to be defined carefully. The most important property of liquid crystal phases is tliat tire molecules have long-range orientational order. For tliis to be possible tire molecules must be anisotropic, whetlier tliis results from a rodlike or disclike shape. 

Materials that contain defects and impurities can exhibit some of the most scientifically interesting and economically important phenomena known. The nature of disorder in solids is a vast subject and so our discussion will necessarily be limited. The smallest degree of disorder that can be introduced into a perfect crystal is a point defect. Three common types of point defect are vacancies, interstitials and substitutionals. Vacancies form when an atom is missing from its expected lattice site. A common example is the Schottky defect, which is typically formed when one cation and one anion are removed from fhe bulk and placed on the surface. Schottky defects are common in the alkali halides. Interstitials are due to the presence of an atom in a location that is usually unoccupied. A... 

A quantitative way of dealing with the degree of disorder in a system is to define something called the thermodynamic probability Q. which counts the number of ways in which a particular state can come about. Thus situations we characterize as relatively disordered can come about in more ways than a relatively ordered state, just as an unordered deck of cards compared to a deck arranged by suits. 

Figure 6 shows the field dependence of hole mobiUty for TAPC-doped bisphenol A polycarbonate at various temperatures (37). The mobilities decrease with increasing field at low fields. At high fields, a log oc relationship is observed. The experimental results can be reproduced by Monte Carlo simulation, shown by soHd lines in Figure 6. The model predicts that the high field mobiUty follows the following equation (37) where d = a/kT (p is the width of the Gaussian distribution density of states), Z is a parameter that characterizes the degree of positional disorder, E is the electric field, is a prefactor mobihty, and Cis an empirical constant given as 2.9 X lO " (cm/V). ...

The primary uses of pyridoxine hydrochloride are in multivitamin supplement tablets and for fortification of human food and animal feed, especially for poultry and pigs. Most breakfast cereals and infant formulas in the United States are supplemented. Lesser amounts are used therapeutically to correct deficiencies or to treat specific disorders. Pyridoxine hydrochloride has been used experimentally to treat a variety of conditions with varying degrees of effectiveness (4,23). Pyridoxine hydrochloride is readily incorporated into premixes and foods. 

Deficiency of the VIIFC portion of the Factor VIII complex results in classic hemophilia or hemophilia A and is inherited as a sex-linked recessive disorder. Based on the degree of deficiency of the VIIFC molecule three different forms of hemophilia A are recognized. Less than 1% VIIFC activity equals severe hemophilia A. Two to 10% of normal VIIFC activity equals moderately severe hemophilia A. Ten to 25% of normal VIIFC activity equals minimal symptomatic disease. Deficiency of the VIIFvWFAg portion of the Factor VIII complex results in von WiUebrand disease. There are at present five principal types of von WiUebrand disease and numerous subtypes or variants. For the most part, von WiUebrand disease is inherited as an autosomal dominant, and a few subtypes may be inherited as an autosomal recessive trait. 

Linear N2 molecules adsorbed on graphite show a transition from a high-temperature phase with orientational disorder to a low-temperature phase with herringbone ordering of the orientational degrees of freedom (see Sec. lie and Fig. 11). 

Hydrophobic interactions <40 Force is a complex phenomenon determined by the degree to which the structure of water is disordered as discrete hydrophobic molecules or molecular regions coalesce. 

Draw ratio Degree of crystallinity Lattice disorder coefficient (k) Average crystallite size perpendicular to the crystallographic plane (hkl) Dhki (nm) ... 

Fig. 6. Same as in Fig. 5 but with random fluctuations introduced after the second quench (see text) near the straight APB. at following t (a) too, (b) 500, (c) 1000, and (d) 2000. The grey level varies linearly with the degree of order. from the completely dark for the most disordered region, to the coinplet.ely white for the most Ordered one. 

Several Intermetallics, for example Ni3Al, are ordered right up to the melting temperature showing only minor variation of order parameter with temperature. In the present paper LRO-kinetics is studied in CusAu, where a Ti of about 390°C allows a considerable variation of the degree of LRO until its complete dissolution. We report on results of recrystallized material as well as samples deformed in the disordered and the ordered state. Part of this work was already presented at an earlier conference. ... 

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