Viscoelastic studies compared with

The dynamic viscoelastic properties of acetylated wood have been determined and compared with other wood treatments in a number of studies. Both the specific dynamic Young s modulus (E /j) and tan S are lower in acetylated wood compared with unmodified wood (Akitsu etal., 1991, 1992, 1993a,b Korai and Suzuki, 1995 Chang etal., 2000). Acetylation also reduces mechanosorptive creep deformation of the modified wood (Norimoto etal., 1992 Yano etal, 1993). In a study of the dynamic mechanical properties of acetylated wood under conditions of varying humidity, it was concluded that the rate of diffusion of moisture into the wood samples was not affected by acetylation (Ebrahimzadeh, 1998). 

Many surfactant solutions are normal Newtonian liquids even up to rather high concentrations. Their viscosities are very small as compared with the viscosity of the solvent water. This is particulary the case for micellar solutions with concentrations up to 20% W/W in which spherical micelles are present. Even in the presence of rodlike micelles the viscosities can be rather low. Systems with rodlike micelles have recently been studied extensively. Missel et al. (1-2) studied alkylsulfate solutions and showed how the lengths of the rods can be varied by the addition of salt or by the detergent concentration. Under all these conditions the solutions are of rather low viscosity. On the other hand, we have studied a number of cationic detergent solutions in which rodlike micelles were formed and which all became quite viscous at rather low concentrations. In addition some of these solutions had elastic properties. The phenomenon of viscoelasticity in detergent solutions is not new. Exten-... 

In a follow up report from Schafer s group [52a] in 2012, largely focused on studying the viscoelastic behavior of the polymer, a modified tris(amidate) yttrium complex was used to initiate ROP of e-caprolactone. This slightly bulkier complex with a diisopro-pylphenyl on the nitrogen instead of dimethylphenyl, gave lower molecular weight polymers of just under 1 x lO g/mol, but of a narrower polydispersity index (PDI) of around 1.5 compared with the values of between 2 and 2.5 achieved in previous studies. 

Abstract. Propagation of capillary waves along the surface of water covered by a homogeneous insoluble film has been a subject of numerous experimental and theoretical studies. However, it has been shown only recently that real surface films contain two-dimensional aggregates, which influence the characteristics of surface waves. The problem of multiple scattering of surface waves by two dimensional viscoelastic particles is considered briefly below. The results can be compared with the experimental data for condensed films with two-dimensional bubbles of gaseous phase. 

Studies of the heat transfer behavior of viscoelastic aqueous polymer solutions have been carried out for turbulent flow in a rectangular channel having an aspect ratio of 0.5. These experimental results obtained with aqueous polyacrylamide solutions are shown in Fig. 10.37, where the minimum asymptotic values of the dimensionless heat transfer coefficient, jH, are compared with the values reported by Cho and Hartnett for turbulent pipe flow. The turbulent pipe flow results are correlated by... 

In this chapter, the simulation scheme will be introduced and illustrated by applying it to the Rouse chain. The computer simulation results of the Rouse-chain model can be directly compared with the analytical solutions to demonstrate the validity of the simulations. This will serve to validate simulations by the same scheme on systems of which analytical solutions are not available. In Chapters 17 and 18, simulations on entanglement-free Fraenkel chains " are studied giving new understandings at the molecular level of polymer viscoelasticity. 

The electrical instability in the electrospinning process was compared to aerodynamic instabilities where partial differential equations of the aerodynamics of the fluid jet with electric field equations are used to describe the process. Many theoretical models have been used to describe the combination of a viscoelastic fluid driven by an electrical field. On the basis of Taylor studies and with the use of high-velocity cameras, it was proposed that the electrospinning... 

The in-plane mechanical, viscoelastic and thermal properties of a satin weave carbon fabric impregnated with an amine cured epoxy resin were studied by Abot and co-workers [74]. The in-plane quasi-static behaviour including the failure modes under tension, compression and shear and all the mechanical properties including elastic moduli and strengths were determined. The viscoelastic properties including the glass transition temperature were also measured as well as the coefficients of thermal expansion. These measured properties for the fabric composites were also compared with their corresponding ones for a unidirectional composite with the same fibre and matrix. 

Nanometer-scale contacts to compliant linear viscoelastic materials can be studied experimentally with the scanning force microscope (SFM). Creep significantly modifies the formation and rupture of these contacts compared to contacts to elastic materials. Not only does the maximum contact area depend on the loading history but, unlike elastic materials, it reaches its maximum value well after the maximum load is applied. Effects due to creep are distinct firom those induced at the periphery of the contact by adhesion. Creep effects dominate adhesion effects in SFM-scale contacts for a wide range of compliant viscoelastic materials. Strategies are presented to optimize experimental parameters for creep studies in SFM-scale contacts to linear viscoelastic materials. 

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