We propose a simple model comprising three particles to study the nonlinear mechanical response of jammed frictional granular materials under oscillatory shear. Owing to the introduction of the simple model, we obtain an exact analytical expression of the complex shear modulus for a system including many monodispersed disks, which satisfies a scaling law in the vicinity of the jamming point. These expressions perfectly reproduce the shear modulus of the many-body system with low strain amplitudes and friction coefficients. Even for disordered many-body systems, the model reproduces the results by introducing a single fitting parameter.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/d2sm01565j | DOI Listing |
Nat Commun
January 2025
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
The development of mechanically robust super-lubrication hydrogel materials with sustained lubricity at high contact pressures is challenging. In this work, inspired by the durable lubricity feature of the earthworm epidermis, a multilevel structural super-lubrication hydrogel (MS-SLH) system, the so-called lubricant self-pumping hydrogel, is developed. The MS-SLH system is manufactured by chemically dissociating a double network hydrogel to generate robust and wrinkled lubrication layer, and then laser etching was used to generate cylindrical texture pores as gland-like pockets for storing lubricants.
View Article and Find Full Text PDFUltrasound Med Biol
January 2025
Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA. Electronic address:
Objective: Measurement of thenar muscle elasticity by ultrasound shear wave elastography (SWE) may be useful for the diagnosis and evaluation of carpal tunnel syndrome (CTS), but there is a paucity of information on SWE of the thenar muscles in patients with CTS. The purpose of this study was to investigate the elasticity of the thenar muscles in patients with CTS.
Methods: Twenty-two adult patients with a referral diagnosis of CTS (27 hands) and 20 healthy volunteers as a control (20 dominant hands) participated in this study.
PLoS One
January 2025
Hebei Provincial Communications Planning, Design and Research Institute Co., Ltd, Shijiazhuang, Hebei, China.
The relationship between the micro technical indexes and the macro road performance of high modulus asphalt (HMA) is helpful for understanding its mechanism and performance, and promoting its application. To explore the relationship, two kinds of high modulus asphalt (HMA), LLDPE/SBS composite modified asphalt and rubber/PPA composite modified asphalt were prepared according to the HMA requirements. Secondly, Molecular models of two kinds of HMA were established through molecular dynamics (MD) simulations, and the high temperature parameters of LLDPE/SBS composite modified asphalt were obtained with the two methods, namely the micro molecular dynamics simulation and high temperature rheological test, respectively.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Engineering, RMIT University, Bundoora, VIC 3083, Australia.
Graphene and its derivatives have been widely used as reinforcing nanofillers for high-performance polymer nanocomposites. The effectiveness of the reinforcement largely depends on the properties of the nanofiller-matrix interface, which can be represented by the interfacial shear strength (IFSS). This work systematically investigates IFSS enhancements for polyethylene (PE) nanocomposites reinforced by graphene origami (GOri) through molecular dynamics pull-out simulations.
View Article and Find Full Text PDF3D Print Addit Manuf
October 2024
Industry Engineering Department, School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an, P.R. China.
The varied material and the inherent complex microstructure make predicting the effective stiffness of fused deposition modeling (FDM) printed polylactic acid (PLA)/carbon fiber (CF) composite a troublesome problem. This article proposes a microstructure scanning electron microscope (SEM) mapping modeling and numerical mean procedure to calculate the effective stiffness of FDM printing PLA/CF laminates. The printed PLA/CF parts were modeled as a continuum of 3D uniform linear elasticity with orthotropic anisotropy, and their elastic behavior was characterized by orthotropic constitutive relations.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!