Results 241 to 250 of about 67,617 (297)

Vanishing Relaxation Limit of Viscoelasticity

Mathematics and Mechanics of Solids, 1996
A rate-type viscoelastic material with very small relaxation time parameter should be almost an elastic material intuitively. In this paper, we shall prove that smooth solutions of initial-boundary value problems, with periodic boundary conditions of a one-dimensional elastic body, can be obtained as the vanishing relaxation limits of the ...
Wu, Yumei, Liu, I-Shih
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Viscoelastic relaxation in fluids

Bulletin of the Russian Academy of Sciences: Physics, 2015
The shear elasticity of different fluids are studied experimentally at relatively low frequencies of 40 and 74 kHz. The real and imaginary shear moduli of several liquids are measured using the acoustic resonance method. A low-frequency viscoelastic relaxation process is assumed to occur in a fluid with a period of relaxation much longer than the ...
B. B. Badmaev, B. B. Damdinov, T. S. Dembelova   +2 more
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Viscoelastic Relaxation in Hydrated Melts

The Journal of Chemical Physics, 1971
Measurements of longitudinal absorption for the system Ca(NO3)2·3.2H2O reveal the presence of a relaxation process. This relaxation is viscoelastic, i.e., the liquid is transformed into a pseudoglass. Shear velocity measurements conform the appearance of a viscoelastic relaxation with the condition τv≈τs in this system.
G. S. Darbari, M. R. Richelson, S. Petrucci   +2 more
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Stress Relaxation of Viscoelastic Material

Transactions of the Society of Rheology, 1974
The stress relaxation of viscoelastic material after cessation of steady-state flow has been investigated. A method is proposed that allows fairly accurate prediction of the shear stress component, P12(t), as well as the first normal stress component, P11–P22(t), for a relatively wide range of time and shear rates.
B. Hlaváček, J. F. Stanislav, F. A. Seyer   +2 more
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Viscoelastic relaxations in thermotropic polybibenzoates

Journal of Non-Crystalline Solids, 1991
Abstract The dynamic mechanical relaxations of two thermotropic polybibenzoates containing the biphenyl group in the main chain have been determined in the temperature range from −150 to 130°C, at several frequencies. The two polyesters are poly(heptamethylene p , p ′-bibenzoate) (P7MB) and poly(oxyditrimethylene p , p ′-bibenzoate) (PDTMB).
J.M Pereña, M.M Marugán, A Bello, E Pérez   +3 more
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Viscoelastic Relaxation in B2O3

1978
The relative ease with which its viscosity can be measured over a wide range of temperature (260–1600°C) has made B2O3 one of the materials most often used to test viscosity theories. It exhibits two Arrhenius regions: a high temperature region between 800–1400°C and a low temperature one, 260–350°C.
P. B. Macedo, C. J. Montrose, C. T. Moynihan, C. C. Lai   +3 more
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Viscoelastic relaxation in supercooled liquids

Discussions of the Faraday Society, 1967
A study has been made of the viscoelastic behaviour of a range of supercooled liquids each of which has a steady-flow viscosity η fitting the equation, ln η=A′+ B′/(T–T0), where T0 is the reference temperature at which no free-volume is available for molecular translational motion. For all the liquids investigated, the limiting shear rigidity modulus G∞
A. J. Barlow, J. Lamb
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Viscoelastic relaxation in supercooled eugenol

Journal of the Chemical Society, Faraday Transactions 2, 1975
Measurements have been made of the viscosity, density, and shear mechanical resistance of eugenol. The relaxational behaviour is described in terms of the complex shear compliance J*(jω)=J∞+ 1/jωη+Jr/(1 + jωτr)β with the parameters Jr/J∞= 1.0, ηJ∞/τr= 2.0 and β= 0.5.
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Viscoelastic Relaxation in Glassy Polymers

MRS Proceedings, 1986
AbstractThe nonequilibrium mechanism controlling the viscoelastic response in the glassy state is analyzed in accordance with our multiple hole energy model. The change in the nonequilibrium glassy state defines the Struik physical aging exponent and determines the motion of the relaxation time spectrum, the transition of the global shift factor and ...
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Viscoelastic relaxations in poly(dimethylphenyl methacrylates)

Polymer Bulletin, 1994
Dynamic mechanical properties of poly(dimethylphenyl methacrylates) were studied considering the different positions of the methyl groups on the phenyl ring. In all cases a clear α relaxation can be observed which is associated to the polymer glass transition temperature (Tg). Nevertheless, at lower temperatures, viscoelastic activity is negligible.
CALLEJA, RD, GARGALLO, L, RADIC, D
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