2 research outputs found
Additional file 1: of Patientsâ experience of recurrent/metastatic head and neck squamous cell carcinoma and their perspective on the EORTC QLQ-C30 and QLQ-H&N35 questionnaires: a qualitative study
1. Literature review and 2. Conceptual Saturation Analysis. Literature review search strategy and list of publications finally included in the development of the patient road map. Results of the conceptual saturation analysis from the 14 patient interviews. (DOCX 84 kb
Viscosity of Ring Polymer Melts
We
have measured the linear rheology of critically purified ring
polyisoprenes, polystyrenes, and polyethyleneoxides of different molar
masses. The ratio of the zero-shear viscosities of linear polymer
melts η<sub>0,linear</sub> to their ring counterparts η<sub>0,ring</sub> at isofrictional conditions is discussed
as a function of the number of entanglements <i>Z</i>. In
the unentangled regime η<sub>0,linear</sub>/η<sub>0,ring</sub> is virtually
constant, consistent with the earlier data, atomistic simulations,
and the theoretical expectation η<sub>0,linear</sub>/η<sub>0,ring</sub> = 2. In
the entanglement regime, the <i>Z</i>-dependence of ring
viscosity is much weaker than that of linear polymers, in qualitative
agreement with predictions from scaling theory and simulations. The
power-law extracted from the available experimental data in the rather
limited range 1 < <i>Z</i> < 20, η<sub>0,linear</sub>/η<sub>0,ring</sub> ∼ <i>Z</i><sup>1.2±0.3</sup>,
is weaker than the scaling prediction (η<sub>0,linear</sub>/η<sub>0,ring</sub> ∼<i> Z</i><sup>1.6±0.3</sup>)
and the simulations (η<sub>0,linear</sub>/η<sub>0,ring</sub> ∼ <i>Z</i><sup>2.0±0.3</sup>). Nevertheless,
the present collection
of state-of-the-art experimental data unambiguously demonstrates that
rings exhibit a universal trend clearly departing from that of their
linear counterparts, and hence it represents a major step toward resolving
a 30-year-old problem