Inextensivity

Collagen is a rigid, inextensible fibrous protein that is a principal constituent of connective tissue in animals, including tendons, cartilage, bones, teeth, skin, and blood vessels. The high tensile strength of collagen fibers in these struc-... 

Undefiniertheit, /, indefiniteness, un-dehnbar, a. inextensible, nonductile. -denk-bar,a. unthinkable, inconceivable, -deutlich,... 

Unvulcanised natural rubber which has been cooled quickly while under tension. In this condition it behaves like a relatively inextensible fibrous material. 

Formerly termed braced tread, rigid breaker or belted tyre. A pneumatic tyre in which the cords of the casing plies run directly across the tyre section from bead to bead, and not at an angle as in a cross-ply tyre the breaker in a radial-ply tyre is an inextensible band which runs circumferentially round the tyre between tread and casing. It is made up of layers of bias cut fabric set at discrete angles to confer the required stability in the tread but maintain the flexibility in the sidewall. 

Various types of inextensible (solid) and resilient supports are illustrated in MSS SP-58. 

Fibres of protein, including the inextensible collagen and the extensible elastic fibres. 

Eshelby, J.D. (1982). The stress on and in a thin inextensible fiber in a stretched elastic medium. Eng. Frac. Mech. 16, 453-455. 

The polypeptide chains are virtually fully extended. There is a little puckering which allows for optimum hydrogen bonding, and hence the structure is inextensible in the direction of the polypeptide chains. On the other hand, there are less specific, hydrophobic (London, dispersion) forces between the sheets, and this permits flexibility. 

Figure 14.6 Illustration of the use of four rollers to form a component with arbitrary curvature distribution. The process takes advantage of the inextensible nature of the plies, which are only required to slide over each other in the roller region...

The particular case of a material reinforced by inextensible rods or fibres has led to the methods of fibre kinematics of Pipkin and Rogers221 and of Spencer23. ... 

The characteristic features of a cord—rubber composite have produced the netting theory (67—70), the cord—inextensible theory (71—80), the classical lamination theory, and the three-dimensional theory (67,81—83). From structural considerations, the fundamental element of cord—rubber composite is unidirectionally reinforced cord—mbber lamina as shown in Figure 5. From the principles of micromechanics and orthotropic elasticity laws, engineering constants of tire T cord composites in terms of constitutive material properties have been expressed (72—79,84). The most commonly used Halpin-Tsai equations (75,76) for cord—mbber single-ply lamina L are expressed in equation 5 ... 

Owing to the inextensible range of complex stabilities extant with various ArH/A combinations, it is important to develop an analytical methodology that is universally applicable and capable of identifying the intermolecular interactions accurately and reliably. As such, in... 

In connection with oxidation, Margolis discussed (218) the selection of catalysts for the extensive and inextensive oxidation of hydrocarbons. The catalysts considered are classified into three major groups (1) metals, (2) metal oxides, and (3) salts of metals and mixtures of oxides. The theory of selection of catalysts has received considerable attention in the literature. In 1909 Fokin related the activities of oxidation catalysts with their ability to form unstable higher oxides. These early ideas were further developed by the Russian chemists Kobozev, Anokhin, and Zimakov. 

Nearly all oxidation reactions involve an electronic mechanism, and on this basis Roginskii has proposed certain orienting rules for the selection of extensive oxidation catalysts. As indicated in Table VI, these rules are based largely upon color and other physical properties which reflect upon the electronic properties of the solid catalyst. Up to the present the application of these selection principles to inextensive oxidation catalysts has been unsuccessful. This is due, in part, to the great diversity in opinions concerning the oxidation mechanism on the catalytic surface and its connection with the inextensive oxidation reaction. Chariot (170) has advanced the idea that the reactions of inextensive and extensive oxidation occur independently and with different reaction velocities. This view, however, has been opposed by Marek (217) who finds it difficult to conceive of a catalyst which would accelerate the... 

Roginskil s concepts of catalyst modification may potentially be of considerable importance in clarifying the basic concepts of the inextensive oxidation process. The practical utilization and verification of this theory has been tested only in a limited number of cases (98,218). 

For the sake of simplicity, we shall discuss solid-liquid, l.e. Inextensible, Interfaces. The model assumptions are the following. 

Most of the early proposals for the structure of collagen were based primarily on an attempt to achieve two objectives (1) to provide a reasonable explanation of the strong 2.86 A meridional reflection and (2) to somehow fit the large number of imino acid residues into the structure. Furthermore, it was generally felt that proposed structures should account for the apparent inextensibility of collagen fibers. ... 

It should be pointed out that Schmitt, et al. (1942) have shown, under certain conditions in the electron microscope, that collagen fibrils can apparently extend manyfold. This led Bear (1952) to suggest that a successful model should allow for such extensibility. However, under all other conditions collagen fibers have proved essentially inextensible beyond about 10% over rest-length, and in recent years this requirement for the collagen structure seems to have been generally abandoned. 

The inextensibility of the worm-like chain implies that 9Rj/9 - Po " flexible beam,... 

In the model of Agarwal and Khakhar [57] the polymer molecules are taken to be bead-rod chains with the hydrodynamic forces concentrated at the beads. The chains may bend about a bead, and a spring force acts to restore the chain to is equilibrium conformation, which is a straight chain. The connecting rods are inextensible. The system is confined to a plane, and the chains diffuse due to Brownian forces resisted by hydrodynamic forces. Hydrodynamic forces resulting from an imposed shear flow deform and orient the molecules. Two chains may react and combine to form a longer chain if the chain ends approach to within the capture radius (a) and if the angle between the chains is less than the critical value (0 ). The reaction is assumed to be very fast (kfj k j ) so that every collision that satisfies the above criteria results in... 

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