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Showing 1 to 20 of 23 for “"linear viscoelasticity"”.
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Relaxations in molecularly thin simple liquid films: Linear viscoelasticity and non-linear response to shear
… relaxations of molecules under confinement, the linear and non-linear response of molecularly thin simple liquid films confined between two solid surfaces were studied. The method was to measure the resistance to applied oscillatory shear deformation as a function of frequency and amplitude of …
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Dynamic stability of shear deformable viscoelastic composite plates
Linear viscoelasticity theory is used to analyze the dynamic stability of composite, viscoelastic flat plates subjected to in-plane, biaxial edge loads. In deriving the associated governing equations, a hereditary constitutive law is assumed. In addition, having in view that composite-type …
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Time dependent mechanical behavior of mammalian collagen fibrils
… studied extensively and was shown to follow non-linear viscoelasticity, as similar quantitative understanding of the time-dependent deformation of individual collagen fibrils is missing, albeit essential for our understanding of the dissipative processes occurring in tissues and the development …
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Analysis of structural development during superdrawing of poly(ethylene terephthalate) fibers
… based on the rubber elasticity theory and non-linear viscoelasticity.
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Response of Flooded Asphalt Pavement using PANDA
… on Biot consolidation theory and Schapery's non-linear viscoelasticity model, was developed to accurately simulate and analyze the detrimental effects of saturated layers in asphalt pavements. In addition, a parametric study is conducted to analyze the response of pavements with varying surface …
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Material and Damping Characterization of Discretized Adhesive Tapes in Cantilever Beams undergoing Free and Forced Vibration
… determined and analytically verified using linear viscoelasticity and basic strength of materials and vibrations principles. These results showed a mean to improve the damping of a structure without increasing the weight of the added damping layer. Third, a nonlinear analysis was performed …
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Viscoelastic characterization of angle ply advanced composites
… and numerical integration methods based on linear viscoelasticity were used to predict constant strain rate and long time creep behavior of composites from nondestructive short time dynamic tests. It has been shown that a regression equation and its constants can be conveniently used to …
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A NUMERICAL STUDY OF NONLINEAR VISCOELASTIC FLOW AND NONISOTHERMAL POWER-LAW FLOW
… fluid flow extends the Maxwell equation of linear viscoelasticity to the non-linear region by letting both relaxation time and elastic modulus depend upon the existing structure. Based on the calculations for a 3:1/1:3 contraction/expansion geometry with fully developed simple shearing flows …
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Interplay of flow and microstructure in complex fluids: Semiflexible polymer solutions and emulsions
… Brownian motion. The dynamics and the non linear viscoelasticity of dilute solutions of semiflexible polymers in shear flow are studied. The effects of chain stiffness and flow strength on the configurational and material properties of semiflexible polymers are discussed. It is shown that …
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Modeling viscoelastic cellular materials for the pressing of wood composites
… models of cellular materials in conjunction with linear viscoelasticity of polymers to develop a nonlinear viscoelasticity model for wood in transverse compression. The approach couples the viscoelastic behavior of the amorphous polymers in wood with the structure imposed by anatomy. These …
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Study of the aging hereditariness of concrete through a novel viscoelastic formulation
… function from the fundamental relationship of linear viscoelasticity. In order to perform creep analyses with the suggested fractional-order law, a numerical integration scheme characterized by a fractional-order viscous kernel is also developed and verified on realistic concrete structures …
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Rheological Studies of Injectable Thermoresponsive Biodegradable Hydrogels and Porcine Ocular Tissues
… of the hydrogels. Both the hydrogels exhibited linear viscoelasticity, and the values of storage moludus (G´) at 1 Hz appeared in the range of 15-35 Pa for P(NIPAAm-co-DEX-Lactate HEMA) gels and 20-40 Pa for P(NIPAAm-co-HA-AEMA) gels at 15 mg·mL-1 concentration. No significant differences were …
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Constitutive modelling of branched polymer melts in non-linear response
… Pompom constitutive equations. Usually the non-linear terms in this model are fitted to uniaxial extensional data due its sensitivity to levels of branching, but in this thesis I will study a number of other non-linear flows using this model. For each flow the results are compared to experiments …
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The Biomechanics of the Perinatal, Neonatal and Pediatric Cervical Spine: Investigation of the Tensile, Bending and Viscoelastic Response
… cervical spine and are modeled with quasi-linear viscoelasticity. Peak load and loading energy increases with increased loading rate, while hysteresis energy is rate insensitive at lower loading rates, but increases at higher rates of loading. These data establish structural response …
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Fluid characterisation and drop impact in inkjet printing for organic semiconductor devices
… used in many of the applications involve non-linear viscoelasticity and their behaviours in the context of inkjet printing have not been fully understood. This thesis aims to characterise Newtonian and non-Newtonian properties of inkjet fluids and identify the key parameters affecting drop …
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Dielectric relaxation behavior of poly(3-hydroxybutyrate)
… developed which is grounded in the theory of linear viscoelasticity with the aim of quantitatively assessing the effect of attempts to improve the toughness of PHB. In the course of data reduction and model development, the majority of empirical dielectric relaxation functions has been …
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Finite element modeling of transient ultrasonic waves in linear viscoelastic media
<p>Linear viscoelasticity offers a minimal framework within which to construct a causal model for wave propagation in absorptive media. Viscoelastic media are often described as media with memory, that is, the present state of stress is dependent on the present strain and the complete time history …
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Nonlinear Viscoelastic Wave Propagation in Brain Tissue
… time has been developed. The assumption of quasi-linear viscoelasticity (QLV) was validated for strain levels of up to 35%. A generalized Rivlin model was used for the isochoric part of the deformation and it was shown that at least three terms (C_10, C_01 and C_11) are needed to accurately …
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Mathematical modelling of growth, reorganisation and active response in cells and tissues
… modelling literature, we employ tools from nonlinear elasticity, active remodelling, and linear viscoelasticity to capture some relevant experimental observations. We find that strain energies belonging to a very general class all give rise to the same preferential orientations of cells on …
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Relaxations in molecularly thin simple liquid films:linear viscoelasticity and non-linear response to shear
… relaxations of molecules under confinement, the linear and nonlinear response of molecularly thin simple liquid films confined between two solid surfaces were studied. The method was to measure the resistance to applied oscillatory shear deformation as a function of frequency and amplitude of …
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