We employ experiment and theory to explore the nonlinear elasticity and yielding of concentrated suspensions of nanoparticles which interact via purely repulsive forces. These glassy suspensions are found to exhibit high exponent power law or simple exponential dependences of the shear elastic modulus and perturbative yield stress on nanoparticle volume fraction, as well as a monotonic decrease of the perturbative yield strain with increasing concentration. Our experimental observations are in good agreement with the predictions of a recently developed microscopic statistical mechanical theory, which describes glassy dynamics based on a nonequilibrium free energy that incorporates local cage correlations and activated barrier hopping processes [(1) Schweizer, K. S.; Saltzman, E. J. J. Chem. Phys. 2003, 119, 1181. (2) Saltzman, E. J.; Schweizer, K. S. J. Chem. Phys. 2003, 119, 1197. (3) Kobelev, V.; Schweizer, K. S. Phy. Rev. E 2005, 71, 021401].
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/la052740x | DOI Listing |
PLoS One
January 2025
Facultad de Ciencias Naturales e Ingenieria, Universidad de Bogota Jorge Tadeo Lozano, Bogota, Colombia.
The Lie group method is a powerful technique for obtaining analytical solutions for various nonlinear differential equations. This study aimed to explore the behavior of nonlinear elastic wave equations and their underlying physical properties using Lie group invariants. We derived eight-dimensional symmetry algebra for the (3+1)-dimensional nonlinear elastic wave equation, which was used to obtain the optimal system.
View Article and Find Full Text PDFGeroscience
January 2025
Department of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA, USA.
Aging is a complex biological process influenced by various factors, including genetic and environmental influences. In this study, we present BayesAge 2.0, an upgraded version of our maximum likelihood algorithm designed for predicting transcriptomic age (tAge) from RNA-seq data.
View Article and Find Full Text PDFJ Neuroeng Rehabil
December 2024
Chair of Autonomous Systems and Mechatronics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
Wearable robots are often powered by elastic actuators, which can mimic the intrinsic compliance observed in human joints, contributing to safe and seamless interaction. However, due to their increased complexity, when compared to direct drives, elastic actuators are susceptible to faults, which pose significant challenges, potentially compromising user experience and safety during interaction. In this article, we developed a fault-tolerant control strategy for torque assistance in a knee exoskeleton and investigated user experience during a walking task while emulating faults.
View Article and Find Full Text PDFTo address the challenges of performing in-situ tests on riverbed overburden gravel, this study employs three scaling methods-equal mass substitution, similar gradation, and the mixed method-to investigate the original gradation of the gravel. Large-scale triaxial consolidated drained shear tests were conducted to evaluate the effects of the maximum particle size reduction ratio (M) and confining pressure on the stress-strain behavior, fractal dimension, particle breakage, and the parameters of the Duncan-Chang model (an elastic model describing nonlinear stress-strain relationships). The study explores how scaling, based on fractal dimension and particle breakage rate, impacts the strength and deformation characteristics of gravel materials.
View Article and Find Full Text PDFBiomech Model Mechanobiol
December 2024
Department of Biomedical Engineering, Virginia Commonwealth University, 401 W. Main St., Richmond, VA, 23284, USA.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!