Resilience, elastic

Prall-heit, /. tightness, tenseness, tension plumpness, -kraft, /. resiliency elasticity, -wand, /. baffle, -winkel, m. angle of reflection. 

Fracture toughness Resilient, elastic Fragile Elastics... 

Resilient (elastic) with a high flex life (flexible lifetime)... 

Striated skeletal muscle fibers are bound together by collagenous connective tissue to form individual muscles. The connective tissue covering a muscle is known as the epimysium. This forms a resilient elastic sheath covering that separates the muscle from surrounding structures such as tendons and bone. 

Historically, these peptides were identified by isolating domains ofinterest from naturally evolved proteins. The tripeptide RGD sequence (arginine-glycine—aspartic acid), a commonly used cell-adhesion domain, is a prime example of this. RGD was isolated in 1983 from the extracellular and plasma protein fibronectin and was identified as the minimal sequence necessary to promote cell-attachment properties (Pierschbacher and Ruoslahti 1984). Other commonly used domains include elastin-hke sequences, which are derived from the protein elastin found in connective tissue (Meyer and Chilkoti 2002), and recombinant-silks (Prince et al. 1995). Both of these peptide domains are used to confer their unique mechanical properties (i.e., resilience, elasticity, and strength) to the resulting biomaterial. 

Promoters perform an important function in the heat treatment of mixtures of butyl rubbers with fillers. Compounds based on the heat treated mixtures have better extrusion and calendering properties than they would have otherwise and their vulcanisates have greater resilience, elasticity, flexibility, abrasion resistance, and electrical resistivity. Various promoters have been withdrawn from the market recently as potential health hazards, but a dispersion of poly-dinitrosobenzene in inert filler, now marketed by Hughson Chemical as PolyDNB, is still available. 

The foregoing is an equilibrium analysis, yet some transient effects are probably important to film resilience. Rayleigh [182] noted that surface freshly formed by some insult to the film would have a greater than equilibrium surface tension (note Fig. 11-15). A recent analysis [222] of the effect of surface elasticity on foam stability relates the nonequilibrium surfactant surface coverage to the foam retention time or time for a bubble to pass through a wet foam. The adsorption process is important in a new means of obtaining a foam by supplying vapor phase surfactants [223]. 

The allowable dimensional variation (the tolerance) of a polymer part can be larger than one made of metal - and specifying moulds with needlessly high tolerance raises costs greatly. This latitude is possible because of the low modulus the resilience of the components allows elastic deflections to accommodate misfitting parts. And the thermal expansion of polymers is almost ten times greater than metals there is no point in specifying dimensions to a tolerance which exceeds the thermal strains. 

The alternative option for counteracting cavitation damage is the use of a resilient material such as rubber. The mechanical forces attendant on collapse of the bubbles are absorbed by elastic deformation of the resilient material. 

Elastomeric polypeptides are a class of very interesting biopolymers and are characterized by mbber-like elasticity, large extensibility before rupture, reversible deformation without loss of energy, and high resilience upon stretching. Their useful properties have motivated their use in a wide variety of materials and biological applications. Here, we focus on two elastomeric proteins and the recombinant polypeptides derived thereof. 

Resilin and elastin, unlike other structural proteins, fulfill both definitions of an elastic material. Colloquially speaking, resilin and elastin are stretchy or flexible. They also fulfill the strict definition of an elastic material, i.e., the ability to deform in proportion to the magnitude of an applied stress without a loss of energy, and the recovery of the material to its original state when that stress is removed. Resilin and elastin are alone in the category of structural proteins (e.g., collagen, silk, etc.) in that they have the correct blend of physical properties that allow the proteins to fulfill both definitions of elasticity. Both proteins have high extensibility and combine that property with remarkable resilience [208]. 

Resilin and elastin have relatively high extensibility and resilience, but as compared to the collagen and the silks, the proteins sacrifice stiffness (elastic modulus) and strength (see Table 2). Collagen and dragUne sflk are much stiffer materials, but lack the extensibility that is characteristic of the rubber-like proteins. On the other hand, the mussel byssus fibers and the viscid silk have the extensibility of resilin and elastin, but lack the resilience [208]. 

The important elastic properties of a material undergoing deformation under static tension are stiffness, elastic strength and resilience. For a material obeying Hooke s law, the modulus of elasticity, E (= o/e), can be taken to be a measure of its stiffness. The elastic... 

It can be easily shown that equivalent expressions for the strain energy per unit volume are U=o e/2 and U = a2/2 E. The modulus of elastic resilience, Ur, of a material is defined as the strain energy absorbed per unit volume when it is stressed to its proportional limit. Thus,... 

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