01762nas a2200169   4500008004100000022001400041245007700055210006900132260007900201300001100280490000700291520111900298100002101417700002101438700002201459856011101481       2010                        eng d  a1539-375500aStrain-rate frequency superposition in large-amplitude oscillatory shear0 aStrainrate frequency superposition in largeamplitude oscillatory  aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMER PHYSICAL SOCcMAR  a0314010 v813 a<p>In a recent work, Wyss et al. [Phys. Rev. Lett. 98, 238303 (2007)] have noted a property of ``soft solids'' under oscillatory shear, the so-called strain-rate frequency superposition. We extend this study to the case of soft solids under large-amplitude oscillatory shear (LAOS). We show results from LAOS studies in a mono-disperse hydrogel suspension, an aqueous gel, and a biopolymer suspension and show that constant strain-rate frequency sweep measurements with soft solids can be superimposed onto master curves for higher harmonic moduli with the same shift factors as for the linear viscoelastic moduli. We show that the behavior of higher harmonic moduli at low frequencies in constant strain- rate frequency sweep measurements is similar to that at large strain amplitude in strain- amplitude sweep tests. We show surface plots of the harmonic moduli and the energy dissipation rate per unit volume in LAOS for soft solids and show experimentally that the energy dissipated per unit volume depends on the first harmonic loss modulus alone, in both the linear and the nonlinear viscoelastic regime.</p>1 aKalelkar, Chirag1 aLele, Ashish, K.1 aKamble, Samruddhi  uhttps://library.ncl.res.in/content/strain-rate-frequency-superposition-large-amplitude-oscillatory-shear-001568nas a2200229   4500008004100000022001400041245007900055210006900134260005700203300001200260490000700272520079800279653002501077653001801102653001301120653000901133100001701142700002101159700002401180700002101204856011301225       2013                        eng d  a0035-451100aRheology and microstructural studies of regenerated silk fibroin solutions0 aRheology and microstructural studies of regenerated silk fibroin  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcNOV  a833-8400 v523 a<p>Regenerated silk fibroin solutions (RSF) are produced by dissolving degummed silk fibers in water. We have observed that RSF solutions at a concentration less than 15 % by weight exhibit an unusual gel-like response in conventional shear rheology measurements. At higher concentrations, the response is predominantly viscous (or liquid-like). We have probed this counterintuitive behavior of silk fibroin solutions by using microrheology, and interfacial rheometry. Scattering techniques were also used to understand the microstructure of RSF solutions as a function of the concentration. Our studies suggest that the gel-like response of the RSF solution may result from the formation of an interfacial film at the air-solution interface, which dominates the bulk rheological response.</p>10aInterfacial rheology10aMicrorheology10aRheology10aSilk1 aNisal, Anuya1 aKalelkar, Chirag1 aBellare, Jayesh, R.1 aLele, Ashish, K.  uhttps://library.ncl.res.in/content/rheology-and-microstructural-studies-regenerated-silk-fibroin-solutions-0