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Showing 1 to 16 of 16 for “"TTSP"”.
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Time, temperature and frequency viscoelastic behavior of commercial polymers
… protocol. Time-temperature superposition (TTSP) of short-term data, at different temperatures, was done. Effective Time Theory (ETT) is used to find the effective time, lambda, as a function of real time, t, from the master curve obtained by TTSP. Dynamic Mechanical Analysis (DMA) tests …
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Displacement rate and temperature effect on asphalt concrete cracking potential
… of time-temperature superposition principle (TTSP) for SCB fracture experiments. In order to accomplish this objective, displacement rates were shifted for each temperature using the shift factors obtained from the complex modulus test conducted for the same AC mixture. According to the …
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Characterization and Response of Thermoplastic Composites and Constituents
… dependent. Using time-temperature superposition (tTSP), the constituent properties are studied as a function of strain rate. Properties that are believed to be significant are fiber tensile properties as a function of strain rate, as well as the through-thickness shear behavior of composite …
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Étude du clivage de l'hémagglutinine de l'influenza par la matriptase
… protéases à sérine transmembranaires de type II (TTSP), particulièrement de la matriptase, a été explorée. Les résultats obtenus démontrent que la matriptase et plusieurs autres enzymes du groupe des TTSP sont exprimées dans l'épithélium bronchique humain. La matriptase et d'autres TTSP peuvent …
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Modeling the High Strain Rate Tensile Response and Shear Failure of Thermoplastic Composites
… the time-Temperature Superposition Principle (tTSP) to strain rates of 10^-4/s to 10^6/s. Other fiber properties are obtained from the same tests, but are assumed to be deterministic. Matrix properties are also assumed to be deterministic and are obtained from mechanical testing of neat matrix …
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Thermoviscoelastic characterization and predictions of Kevlar/epoxy composite laminates
… The Time-Temperature-Superposition-Principle (TTSP) was used successfully to accelerate the characterization process. A nonlinear constitutive model was developed to describe the stress dependent viscoelastic response for each of the material properties. A new numerical procedure to predict …
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Characterization of the Interfacial Fracture of Solvated Semi-Interpenetrating Polymer Network (S-IPN) Silicone Hydrogels with a Cyclo-Olefin Polymer (COP)
… The time-temperature superposition principle (TTSP) was applied to the crack propagation rate versus SERR curves by shifting the crack propagation rates with the Williams-Landel-Ferry (WLF) equation-based shift factors developed for the bulk behavior of each hydrogel. The application of TTSP …
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Aging model for commercial polymers
… theory and time-temperature superposition (TTSP) methods proposed by Struik, as well as variations of these methods, as proposed by Chai and McCrum, Guerdoux et al. and others. The creep data generated by this study show that the time-dependent creep properties of these materials can be …
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Development of tension and compression creep models for wood using the time-temperature superposition principle
… the Time-Temperature Superposition Principle (TTSP). The principle states that the long-term response of a polymer at lower temperature is equivalent to the short-term response at a higher temperature. Accelerated creep tests were conducted in tension and compression using small clear specimens …
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Wetlaid Cellulose Fiber-Thermoplastic Hybrid Composites - Effects of Lyocell and Steam Exploded Wood Fiber Blends
… of the time-temperature superposition principle (TTSP) made it possible to predict storage moduli over extended frequencies for PP and its composites. Comparison of shift factor versus temperature plots revealed decreasing relaxation times of PP with increasing lyocell concentration, which …
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Long-term creep modeling of wood using time temperature superposition principle
… the time temperature superposition principle (TTSP) for kiln-dried southern pine loaded in compression parallel-to-grain and exposed to constant environmental conditions (~70°F, ~9%EMC). Short-term accelerated creep (17 hour) and recovery (35 hour) data were collected for each specimen at a …
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Understanding the effect of nanofillers on the properties of polypropylene and glass fiber/polypropylene multiscale composites
… the time temperature superposition principle (TTSP), at long loading times. The equivalence between the time strain- and time temperature- superposition principle was substantiated by comparing the correspondent superimposed master curves. The nanofilled PP matrices have also been used for the …
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Studying the Effects of Thermo-oxidative Aging on the Mechanical, Tribological and Chemical Properties of Styrene-butadiene Rubber
… the time-temperature superposition principle (TTSP). The friction coefficient was estimated from the storage and loss modulus using a simplified form of the Persson equation [1]. CLD was also estimated from DMA data. Wear experiments were conducted on the Dynamic Friction Tester (DFT) for …
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Effects of Long-Term Creep on the Integrity of Modern Wood Structures
Short-term creep tests in tension and in compression were conducted on southern pine, Douglas-fir, yellow-poplar, and Parallam™ samples at temperatures ranging between 20 and 80° C and at 6, 9 and 12% moisture content. The principle of time-temperature superposition was applied to form a master …
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The effect of environmental aging/exposure on the durability of high performance polymeric composites
… were made using Time-Temperature Superposition (TTSP) and Effective Time Theory (ETT) techniques. The IM8/954-2 composites behaved in an anomalous fashion at times. This may be attributable to the blended nature of the 954-2 resin system, possible post-curing and phase separation of the resin, …
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Long-term Durability Characterization and Prediction of a Urethane-based Adhesive
Polymeric adhesives play an increasingly critical role in today's engineering designs. When used, adhesively bonded components reduce or eliminate the need for bolted or welded connections. In many cases, this can reduce stress concentrations and weight. With energy dissipating adhesives, noise and …