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Definition families

Definition Family of syn. polymers contg. a repeating silicon-oxygen backbone with org. side groups attached via carbon-silicon bonds classified as fluids, resins, and elastomers Formula [—OSiR2—]n, R not equal to H Properties Liq., semisolid, or solid cis 1 to >1,000,000 cs water repellent sol. in most organic solvents... [Pg.3925]

This study has permitted the definition of the minimum requirements to be introduced in RCCM code in order to select properly the dye penetrant product family. [Pg.621]

Within the scope of the original definition, a very wide variety of ionomers can be obtained by the introduction of acidic groups at molar concentrations below 10% into the important addition polymer families, followed by partial neutralization with metal cations or amines. Extensive studies have been reported, and useful reviews of the polymers have appeared (3—8). Despite the broad scope of the field and the unusual property combinations obtainable, commercial exploitation has been confined mainly to the original family based on ethylene copolymers. The reasons for this situation have been discussed (9). Within certain industries, such as flexible packaging, the word ionomer is understood to mean a copolymer of ethylene with methacrylic or acryhc acid, partly neutralized with sodium or zinc. [Pg.404]

In the course of the study, we found that a family of monosaccharides exhibited a definite adsoi ption selectivity (Langmuir s isotherm adsoi ption constant), reflecting their molecular stmctures. [Pg.352]

Family of the scientist has presented documentar y materials to Academy of sciences in June 1974. Among them, the most important ar e manuscripts, typewritten copies about 100 scientific works of the scientist and working materials to them. Its includes articles, reports, monographs, the textbooks written by A.K. Babko during last 25 year s working writing-books with extracts, marks on various questions, abstracts of chemical literature responses and reviews on thesis of Ph.D. and doctor s degrees, on ar ticles, books, textbooks. For example, early works Product of solubility , To a technique of definition of strontium in minerals (1940-s), many unpublished works in 1940-1960, etc. [Pg.406]

Instead of the definition in Eq. (7-82), the selectivity is often written as log k,). Another way to consider a selectivity-reactivity relationship is to compare the relative effects of a series of substituents on a pair of reactions. This is what is done when Hammett plots are made for a pair of reactions and their p values are compared. The slope of an LEER is a function of the sensitivity of the process being correlated to structural or solvent changes. Thus, in a family of closely related LFERs, the one with the steepest slope is the most selective, and the one with the smallest slope is the least selective.Moreover, the intercept (or some arbitrarily selected abscissa value, usually log fco for fhe reference substituent) should be a measure of reactivity in each reaction series. Thus, a correlation should exist between the slopes (selectivity) and intercepts (reactivity) of a family of related LFERs. It has been suggested that the slopes and intercepts should be linearly related, but the conditions required for linearity are seldom met, and it is instead common to find only a rough correlation, indicative of normal selectivity-reactivity behavior. The Br nsted slopes, p, for the halogenation of a series of carbonyl compounds catalyzed by carboxylate ions show a smooth but nonlinear correlation with log... [Pg.372]

Y(t + )] thus, F+(x) = Fz(z). This definition is a straightforward generalization of our earlier definition of the distribution function of a one-dimensional random variable. More generally, given a family of... [Pg.143]

A stochastic process is a family of random variables X( depending on a parameter t (e.g., time). This definition may be extended to include... [Pg.269]

Psychosocial and environmental factors play a major role in the development and recovery from opioid dependence however, a detailed discussion is beyond the scope of this chapter. In general, the use of such drugs as marijuana and alcohol precedes the use of opioids (Clayton and Voss 1981 Kandel and Faust 1975). Although one cannot predict definitively which users will proceed to opioid use, those who do generally have low self-esteem, disrupted families, and/or difficult relationships with their parents. The increased availability of opioids in inner cities of major urban centers contributes to initiation of use and relapse. It is particularly difficult to avoid use and relapse in areas with high unemployment, poor school systems, and high crime rates, because living in such an area may contribute to the very affects opioid use temporarily reheves. [Pg.67]

The aldehyde oxidoreductase from Desulfovibrio gigas shows 52% sequence identity with xanthine oxidase (199, 212) and is, so far, the single representative of the xanthine oxidase family. The 3D structure of MOP was analyzed at 1.8 A resolution in several states oxidized, reduced, desulfo and sulfo forms, and alcohol-bound (200), which has allowed more precise definition of the metal coordination site and contributed to the understanding of its role in catalysis. The overall structure, composed of a single polypeptide of 907 amino acid residues, is organized into four domains two N-terminus smaller domains, which bind the two types of [2Fe-2S] centers and two much larger domains, which harbor the molybdopterin cofactor, deeply buried in the molecule (Fig. 10). The pterin cofactor is present as a cytosine dinucleotide (MCD) and is 15 A away from the molecular surface,... [Pg.398]

This pardaxin model is not unique. We have developed several similar models that are equally good energetically and equally consistent with present experimental results. It is difficult to select among these models because the helices can be packed a number of ways and the C-terminus appears very flexible. Our energy calculations are far from definitive because they do not include lipid, water, ions, membrane voltage, or entropy and because every conformational possibility has not been explored. The model presented here is intended to illustrate the general folding pattern of a family of pardaxin models in which the monomers are antiparallel and to demonstrate that these models are feasible. [Pg.362]

Methodology. Several radioimmunoassays of human calcitonin (hCT) have been developed In the past 5 years (18-20). Their greatest utility has been In the definitive diagnosis of patients with medullary carcinoma of the thyroid gland (MTC) and, recently. In Identifying family members of these patients who have occult MTC. [Pg.51]


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See also in sourсe #XX -- [ Pg.278 , Pg.283 ]




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