Abstract：
:For decades, scientists have debated whether supercooled liquids stop flowing below a glass transition temperature [Formula: see text] or whether motion continues to slow gradually down to zero temperature. Answering this question is challenging because human time scales set a limit on the largest measurable viscosity, and available data are equally well fit to models with opposite conclusions. Here, we use short simulations to determine the nonequilibrium shear response of a typical glass-former, squalane. Fits of the data to an Eyring model allow us to extrapolate predictions for the equilibrium Newtonian viscosity [Formula: see text] over a range of pressures and temperatures that change [Formula: see text] by 25 orders of magnitude. The results agree with the unusually large set of equilibrium and nonequilibrium experiments on squalane and extend them to higher [Formula: see text] Studies at different pressures and temperatures are inconsistent with a diverging viscosity at finite temperature. At all pressures, the predicted viscosity becomes Arrhenius with a single temperature-independent activation barrier at low temperatures and high viscosities ([Formula: see text] Pa[Formula: see text]s). Possible experimental tests of our results are outlined.
journal_name
Proc Natl Acad Sci U S Aauthors
Jadhao V,Robbins MOdoi
10.1073/pnas.1705978114subject
Has Abstractpub_date
2017-07-25 00:00:00pages
7952-7957issue
30eissn
0027-8424issn
1091-6490pii
1705978114journal_volume
114pub_type
杂志文章abstract：:Avian leukosis virus subgroup J (ALV-J) is an important concern for the poultry industry. Replication of ALV-J depends on a functional cellular receptor, the chicken Na+/H+ exchanger type 1 (chNHE1). Tryptophan residue number 38 of chNHE1 (W38) in the extracellular portion of this molecule is a critical amino acid for...
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